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Initial Pythium species composition and Brassicaceae seed meal type influence extent of Pythium-induced plant growth suppression in soil  

Science.gov (United States)

The composition of Pythium spp. populations differs significantly among agronomic soils resulting in site to site variation in the relative importance of these pathogens to growth and development of agronomically important crop species. Brassicaceae seed meal (SM) amendments differentially influen...

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Two Widely Accessible Media for Growth and Reproduction of Phytophthora and Pythium Species †  

Science.gov (United States)

Tomato agar and soybean agar were found to be comparable to or in some cases better than the popular V8 vegetable juice agar in supporting linear growth of Phytophthora cactorum, Phytophthora capsici, Phytophthora parasitica, Pythium aphanidermatum, and Pythium splendens; sporangium production of P. capsici, P. palmivora, and Pythium splendens; and oospore formation of P. cactorum, P. parasitica, Pythium aphanidermatum and Pythium splendens. These two media with readily accessible ingredients can be used to substitute for V8 juice agar in pathological and physiological studies of these two important groups of fungi in countries where V8 vegetable juice is not available or difficult to obtain.

Guo, L. Y.; Ko, W. H.

1993-01-01

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Two widely accessible media for growth and reproduction of phytophthora and pythium species.  

UK PubMed Central (United Kingdom)

Tomato agar and soybean agar were found to be comparable to or in some cases better than the popular V8 vegetable juice agar in supporting linear growth of Phytophthora cactorum, Phytophthora capsici, Phytophthora parasitica, Pythium aphanidermatum, and Pythium splendens; sporangium production of P. capsici, P. palmivora, and Pythium splendens; and oospore formation of P. cactorum, P. parasitica, Pythium aphanidermatum and Pythium splendens. These two media with readily accessible ingredients can be used to substitute for V8 juice agar in pathological and physiological studies of these two important groups of fungi in countries where V8 vegetable juice is not available or difficult to obtain.

Guo LY; Ko WH

1993-07-01

4

Two widely accessible media for growth and reproduction of phytophthora and pythium species.  

Science.gov (United States)

Tomato agar and soybean agar were found to be comparable to or in some cases better than the popular V8 vegetable juice agar in supporting linear growth of Phytophthora cactorum, Phytophthora capsici, Phytophthora parasitica, Pythium aphanidermatum, and Pythium splendens; sporangium production of P. capsici, P. palmivora, and Pythium splendens; and oospore formation of P. cactorum, P. parasitica, Pythium aphanidermatum and Pythium splendens. These two media with readily accessible ingredients can be used to substitute for V8 juice agar in pathological and physiological studies of these two important groups of fungi in countries where V8 vegetable juice is not available or difficult to obtain. PMID:16349002

Guo, L Y; Ko, W H

1993-07-01

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Effect of Microbial Antagonists on in vitro Growth of Pythium aphanidermatum  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Forty-one isolates of 38 species of fungi and 24 isolates of 8 species of bacteria were tested in dual culture plates. Penicillium sp., 2 unidentified bacteria and a sterile fungus were found to inhibit the growth of Pythium aphanidermatum producing zones of inhibitions of 7, 11,4 ...

Imran Ali Siddiqui

6

Growth of cellulolytic bacteria on sugarcane bagasse  

Energy Technology Data Exchange (ETDEWEB)

The growth behavior of Cellulomonas has been examined in fermentation systems using alkali pretreated sugarcane bagasse. During the batch operation diauxic growth was found which would not seem to be explained by catabolic repression. The relative variation of cellulose and hemicellulose during the fermentation process suggests the initial utilization of easily degradable substrate, i.e., hemicellulose and amorphous cellulose, until their concentration becomes limiting, followed by utilization of the crystalline cellulose. The conversion of substrate was 70% with a yield of 0.355 g of biomass per gram of bagasse feed. (Refs. 13).

Enriquez, A.

1981-07-01

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Plant growth promotion and biological control of Pythium aphanidermatum, a pathogen of cucumber, by endophytic actinomycetes.  

UK PubMed Central (United Kingdom)

AIMS: To evaluate the potential of Actinoplanes campanulatus, Micromonospora chalcea and Streptomyces spiralis endophytic in cucumber roots, to promote plant growth and to protect seedlings and mature plants of cucumber from diseases caused by Pythium aphanidermatum, under greenhouse conditions. METHODS AND RESULTS: Three endophytic isolates, out of 29, were selected through tests aimed at understanding their mechanisms of action as biocontrol agents and plant growth promoters. When applied individually or in combination, they significantly promoted plant growth and reduced damping-off and crown and root rot of cucumber. The combination of the three isolates resulted in significantly better suppression of diseases and plant growth promotion, than where the plants were exposed to individual strains. CONCLUSIONS: The three selected actinomycete isolates colonized cucumber roots endophytically for 8 weeks, promoted plant growth and suppressed pathogenic activities of P. aphanidermatum on seedling and mature cucumber plants. SIGNIFICANCE AND IMPACT OF THE STUDY: The results clearly show that the endophytic, glucanase-producing actinomycetes used, especially as a combined treatment, could replace metalaxyl, which is the currently recommended fungicide for Pythium diseases in the United Arab Emirates. These endophytic isolates also have the potential to perform as plant growth promoters, which is a useful attribute for crop production in nutrient impoverished soils.

El-Tarabily KA; Nassar AH; Hardy GE; Sivasithamparam K

2009-01-01

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Controle biológico da podridão de raiz causada por Pythium aphanidermatum e promoção de crescimento de alface hidropônica com Clonostachys rosea Biological control of Pythium aphanidermatum root rot and growth promotion of hydroponic lettuce by Clonostachys rosea  

Directory of Open Access Journals (Sweden)

Full Text Available Clonostachys rosea foi avaliado como promotor de crescimento e no controle da podridão de raiz (Pythium aphanidermatum) em sistemas de fluxo laminar de nutrientes (NFT) e "floating". Na promoção de crescimento, Clonostachys (0, 10³, 10(4), 10(5), 10(6) e 10(7) conídios/mL) foi introduzido na solução nutritiva (SN) e avaliada a massa das plantas. O biocontrole, em sistema NFT, foi avaliado introduzindo Clonostachys na SN (10(6) conídios/mL) i. um dia após o transplantio na ausência do patógeno; ii. três dias antes e no momento da infestação com Pythium e, iii. três dias antes, no momento e três dias após infestação com Pythium. Em sistema "floating", Clonostachys foi introduzido na SN (10(6) conídios/mL) i. quatro dias antes e no momento da infestação com Pythium, e ii. quatro dias antes, no momento e quatro dias após a infestação com Pythium. Nesses experimentos foram determinadas as massas das plantas, e a recuperação do patógeno e antagonista. O antagonista não promoveu o crescimento das plantas, entretanto protegeu-as do subdesenvolvimento causado pelo patógeno no sistema NFT. Não foi observada proteção em sistema "floating". Clonostachys reduziu a incidência do patógeno nas raízes no sistema NFT em 28,6% e 42,8%, quando aplicado duas e três vezes, respectivamente.Clonostachys rosea was evaluated for growth promotion and control of root rot (Pythium aphanidermatum) in hydroponic lettuce in NFT and floating systems. For growth promotion, Clonostachys (0, 10³, 10(4), 10(5), 10(6) and 10(7) conidia/mL) was added in nutrient solution (NS) and the mass of the plants was measured. To evaluate the control of the disease in NFT, Clonostachys was applied to the NS (10(6) conidia/mL) i. one day after transplanting in the absence of Pythium; ii. three days before and simultaneously with Pythium infestation; and, iii. three days before, simultaneously and three days after Pythium infestation. To evaluate the control of root rot in floating system, Clonostachys was added in NS (10(6) conidia/mL) i. four days before, and at the moment of pathogen infestation, and, ii. four days before, simultaneously, and four days after pathogen infestation. Plant mass and the recovery of pathogen and antagonist from the roots were evaluated. Clonostachys did not improve plant growth in the absence of Pythium. In the NFT system Clonostachys protected the plants from yield losses caused by Pythium, but not in the floating system. Pythium recovery from the roots was reduced by 28,6% and 42,8% when Clonostachys was applied two or three times, respectively.

Élida B Corrêa; Wagner Bettiol; Marcelo A.B Morandi

2010-01-01

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EFEITO DE DIFERENTES CONCENTRAÇÕES DE BENOMYL E PCNB SOBRE O CRESCIMENTO RADIAL DE Fusarium solani E Pythium sp., IN VITRO EFFECT OF DIFFERENT CONCENTRATIONS OF BENOMYL AND PCNB ON THE RADIAL GROWTH OF Fusarium solani AND Pythium sp. IN VITRO  

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Full Text Available Os experimentos foram realizado nas dependências do Laboratório de Fitopatologia da Universidade Federal de Goiás, no ano de 1997. Os fungos Fusarium e Pythium sp. foram cultivados em meio de cultura artificial contendo benomyl e PCNB nas concentrações de 10, 25, 50 e 100ppm. Os crescimentos radiais dos fungos demonstraram que o benomyl foi eficiente contra o Fusarium, mas não surtiu efeito contra o Pythium, fato este também observado em relação ao PCNB. Este produto, embora menos eficiente, reduziu em mais de 50% o crescimento radial de Fusarium, obtendo uma redução progressiva com o aumento da concentração. PALAVRAS-CHAVE: Fusarium; Pythium; benomyl; quintozene. The experiments were carried out at Laboratory of Phytopathology of the Escola de Agronomia of the Universidade Federal de Goiás, in the year of 1997. The fungi Fusarium moniliforme and Pythium sp. were treated in cultural medium with benomyl and PCNB in the concentrations of 10, 25, 50 e 100ppm. The radial growth of the fungi demonstrated that benomyl was efficient against Fusarium, but not against Pythium sp. The same was also observed with PCNB. Although less efficient than benomyl, this product reduced radial growth of Fusarium in more than 50%. The increase of PCNB concentration reduced Fusarium growth progressively. KEY-WORDS: Fusarium; Pythium; benomyl; PCNB.

Wilson Ferreira de Oliveira; Luciana Peliz Machado; Antonio Cassio de Oliveira Filho

2007-01-01

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Exploitation of trichoderma species on the growth of Pythium Aphanidermatum in Chilli  

Scientific Electronic Library Online (English)

Full Text Available Abstract in english Damping-off of chilli caused by Pythium aphanidermatum is a major nursery disease in vegetables. In vitro experiments evaluated the effect of eight isolates of Trichoderma species (from chilli rhizosphere) were tested against P. aphanidermatum. All the Trichoderma species had varied antagonistic effects against the pathogen. Among them, TVC3 recorded maximum growth inhibition of P. aphanidermatum and produced more amounts of volatile and non-volatile metabolites. The cult (more) ure filtrate of the Trichoderma isolate TVC3 recorded complete inhibition on the mycelial growth of pathogen at 15% concentration. Moreover, chilli seeds treated with culture filtrate of the isolate TVC3 recorded maximum germination percentage, shoot length, root length and vigour index of chilli. The study identified the Trichoderma isolate (TVC3) performed well in inhibiting the mycelial growth of pathogen as well as increased the plant growth in chilli.

Muthukumar, A.; Eswaran, A.; Sanjeevkumas, K.

2011-12-01

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Exploitation of trichoderma species on the growth of Pythium Aphanidermatum in Chilli  

Directory of Open Access Journals (Sweden)

Full Text Available Damping-off of chilli caused by Pythium aphanidermatum is a major nursery disease in vegetables. In vitro experiments evaluated the effect of eight isolates of Trichoderma species (from chilli rhizosphere) were tested against P. aphanidermatum. All the Trichoderma species had varied antagonistic effects against the pathogen. Among them, TVC3 recorded maximum growth inhibition of P. aphanidermatum and produced more amounts of volatile and non-volatile metabolites. The culture filtrate of the Trichoderma isolate TVC3 recorded complete inhibition on the mycelial growth of pathogen at 15% concentration. Moreover, chilli seeds treated with culture filtrate of the isolate TVC3 recorded maximum germination percentage, shoot length, root length and vigour index of chilli. The study identified the Trichoderma isolate (TVC3) performed well in inhibiting the mycelial growth of pathogen as well as increased the plant growth in chilli.

A. Muthukumar; A. Eswaran; K. Sanjeevkumas

2011-01-01

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Effect of Microbial Antagonists on in vitro Growth of Pythium aphanidermatum  

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Full Text Available Forty-one isolates of 38 species of fungi and 24 isolates of 8 species of bacteria were tested in dual culture plates. Penicillium sp., 2 unidentified bacteria and a sterile fungus were found to inhibit the growth of Pythium aphanidermatum producing zones of inhibitions of 7, 11,4 and 6 mm respectively, around the colony of the pathogen. One strain each of Rhizobium meliloti, Bradyrhizobium sp., and Pseudomonas aeruginosa initially producing zones of inhibition of 15, 20 and 2 mm respectively, but later the pathogen grew and colonies met each other. Similarly, G. , virens initially produced a zone of inhibition of 20 mm but later on the pathogen over grew the zone of inhibition and colonies intermingled. A strain of P. aeruginosa also inhibited the growth of P. aphanidermatum without producing zone of inhibition.

Imran Ali Siddiqui

2001-01-01

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Controle biológico da podridão de raiz causada por Pythium aphanidermatum e promoção de crescimento de alface hidropônica com Clonostachys rosea/ Biological control of Pythium aphanidermatum root rot and growth promotion of hydroponic lettuce by Clonostachys rosea  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese Clonostachys rosea foi avaliado como promotor de crescimento e no controle da podridão de raiz (Pythium aphanidermatum) em sistemas de fluxo laminar de nutrientes (NFT) e "floating". Na promoção de crescimento, Clonostachys (0, 10³, 10(4), 10(5), 10(6) e 10(7) conídios/mL) foi introduzido na solução nutritiva (SN) e avaliada a massa das plantas. O biocontrole, em sistema NFT, foi avaliado introduzindo Clonostachys na SN (10(6) conídios/mL) i. um dia após o transp (more) lantio na ausência do patógeno; ii. três dias antes e no momento da infestação com Pythium e, iii. três dias antes, no momento e três dias após infestação com Pythium. Em sistema "floating", Clonostachys foi introduzido na SN (10(6) conídios/mL) i. quatro dias antes e no momento da infestação com Pythium, e ii. quatro dias antes, no momento e quatro dias após a infestação com Pythium. Nesses experimentos foram determinadas as massas das plantas, e a recuperação do patógeno e antagonista. O antagonista não promoveu o crescimento das plantas, entretanto protegeu-as do subdesenvolvimento causado pelo patógeno no sistema NFT. Não foi observada proteção em sistema "floating". Clonostachys reduziu a incidência do patógeno nas raízes no sistema NFT em 28,6% e 42,8%, quando aplicado duas e três vezes, respectivamente. Abstract in english Clonostachys rosea was evaluated for growth promotion and control of root rot (Pythium aphanidermatum) in hydroponic lettuce in NFT and floating systems. For growth promotion, Clonostachys (0, 10³, 10(4), 10(5), 10(6) and 10(7) conidia/mL) was added in nutrient solution (NS) and the mass of the plants was measured. To evaluate the control of the disease in NFT, Clonostachys was applied to the NS (10(6) conidia/mL) i. one day after transplanting in the absence of Pythium; (more) ii. three days before and simultaneously with Pythium infestation; and, iii. three days before, simultaneously and three days after Pythium infestation. To evaluate the control of root rot in floating system, Clonostachys was added in NS (10(6) conidia/mL) i. four days before, and at the moment of pathogen infestation, and, ii. four days before, simultaneously, and four days after pathogen infestation. Plant mass and the recovery of pathogen and antagonist from the roots were evaluated. Clonostachys did not improve plant growth in the absence of Pythium. In the NFT system Clonostachys protected the plants from yield losses caused by Pythium, but not in the floating system. Pythium recovery from the roots was reduced by 28,6% and 42,8% when Clonostachys was applied two or three times, respectively.

Corrêa, Élida B; Bettiol, Wagner; Morandi, Marcelo A.B

2010-08-01

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Evaluation of plant growth-promoting rhizobacteria for biological control of Pythium root rot of cucumbers grown in rockwool and effects on yield.  

UK PubMed Central (United Kingdom)

Three strains ofPseudomonas fluorescens (63-49, 63-28, and 15), one strain ofPseudomonas corrugata (13) and one strain ofSerratia plymuthica (R1GC4) were tested on rockwool-grown cucumbers for their ability to reduce Pythium root-rot caused byPythium aphanidermatum. These strains were previously selected for biocontrol ability from collections of >4000 bacteria. Strains 63-49 and 63-28 were tested on cucumber plants grown in rockwool in two replicatedPythium-inoculated trials conducted in British Columbia (B.C). Another inoculated, replicated trial was conducted in Quebec with all five strains. Cucumber yields (fruit number and weight) were measured over a ten-week harvest period. Strain 63-49 caused an early promotion of plant growth and increased cucumber yields at early harvests. No measurable effect ofPythium inoculation on disease development was observed in the Quebec trial, due to unfavourable cool weather. However, 63-49 significantly increased the total number of cucumbers (12%) and cucumber weight (18%), compared to the non-treated control. Strains 13, 15 and R1GC4 slightly increased the cumulative cucumber yields, but strain 63-28 had no effect. In the B.C. trial, inoculation withP. aphanidermatum reduced the number and weight of cucumbers by 27%. Treatments ofPythium-inoculated cucumbers with 63-49 significantly increased fruit number and weight by 18%, compared to thePythium-inoculated control. Strain 63-28 increased the cumulative number of cucumbers over time, compared to thePythium-inoculated control, but the increase was less than with 63-49. The use ofPseudomonas spp. in rockwool-grown cucumbers can increase yields, both in the presence and absence of Pythium root rot, and with variable seasonal conditions and disease pressures.

McCullagh M; Utkhede R; Menzies JG; Punja ZK; Paulitz TC

1996-10-01

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Pythium Genetics  

Science.gov (United States)

This is a book chapter on the genetics of Pythium to be published in a book titled "Oomycete Genetics and Genomics: Biology, Interactions with Plants and Animals, and Toolbox." It covers the basic taxonomic classification of species in the genus, the phylogenetic placements, and reviews the literatu...

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Biocontrol traits of plant growth suppressive arbuscular mycorrhizal fungi against root rot in tomato caused by Pythium aphanidermatum  

DEFF Research Database (Denmark)

Arbuscular mycorrhizal (AM) fungi known to cause plant growth depressions in tomato were examined for their biocontrol effects against root rot caused by Pythium aphanidermatum. The main hypothesis was that plant growth suppressive AM fungi would elicit a defence response in the host plant reducing Pythium root rot development. To test this hypothesis a fully factorial experiment was performed with AM fungi (Glomus intraradices, G. mosseae, G. claroideum or nonmycorrhizal), Pythium (± P. aphanidermatum) and harvest (7 and 14 days after pathogen inoculation (dapi)) as the main factors. Two weeks after AM fungi inoculation, roots were challenged with P. aphanidermatum. Variables evaluated at each harvest were root colonization levels of the interacting fungi, plant growth responses, and expression of a plant pathogenesis related protein gene (PR-1). All of the tested AM fungi caused marked growth suppressions, but did not affect PR-1 gene expression or the phosphorous concentration in the host plant. Plants singly inoculated with P. aphanidermatum had an increased PR-1 expression and phosphorous concentration. Among the AM fungi included in the study only G. intraradices reduced the pathogen root infection level, measured both in terms of Pythium ELISA and by recovery on selective media and only at the first harvest. Likewise, P. aphanidermatum root infection reduced colonization levels of G. intraradices, but not that of the two other AM fungi. In conclusion, plant growth suppressive AM fungi may offer plant beneficial traits in terms of biocontrol of root cortical pathogens.

Larsen, John; Graham, James H.

2012-01-01

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Effect of Benomyl Treated Garlic on Growth and Sporulation of Pythium aphanidermatum and Achlya americana  

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Full Text Available Thirteen species belonging to six genera of zoosporic fungi, yielding 356 fungal colonies were isolated from 30 soil samples collected from Sohag city. The effect of different levels (0.0, 50.0, 100.0, 150.0 and 300.0 ppm) of the fungicide benomyl on the morphological structures of mycelial, zoosporangia, sexual organs and gemmae of Pythium aphanidermatum and Achlya americana was studied on malt extract medium and callus cultures of garlic. Steroles was determined in garlic callus cultures treated with different levels of benomyl fungicide. GLC analysis showed differences in sterol contents between treated calli of garlic and control ones, which did not meet Achlya americana and Pythium aphanidermatum fungi requirements.

Gamalat A. Abd-Elaah; A.A. Galal

2006-01-01

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Sugarcane Leaf Photosynthesis and Growth Characters during Development of Water-Deficit Stress  

Science.gov (United States)

Yield and profitability of sugarcane grown on sand soils are much lower than on organic soils in Florida due to biotic and abiotic stresses. A greenhouse study was conducted using a sand soil to identify effects of water deficit stress (WS) during sugarcane early growth on leaf photosynthetic compon...

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Sugarcane yield response to deficit irrigation at two growth stages  

International Nuclear Information System (INIS)

In order to increase crop water use efficiency, a field study in northern Ivory Coast on sugarcane (Saccharum officinarum L.) yield response to deficit irrigation during both tillering and stem elongation stages was carried out at Institut des Savanes (IDESSA) experimental station of Ferkessedougou. The can crop tested was Co 449, an early-maturing genotype of Indian origin. This experiment was conducted for three consecutive years as virgin crop (from November, 1991 to December, 1992) first ratoon crop (from December, 1992 to January, 1994) and as second ratoon crop (from January, 1994 to January, 1995). The experimental design was a randomized complete block with 10 irrigation treatments in 4 replicates of plots 54 m2. Water was applied through an improved furrow irrigation system. Crop water consumption was estimated using the water balance approach based on neutron probe and tensiometer measurements. This field water balance method required the determination of soil hydraulic conductivity as a function of water content and the neutron calibration curve. Data presented are related to the two ratton crops for which field water balance measurements were investigated. It has been shown in the study that sugarcane growth and yield decline owing to water deficit is significantly high during stem elongation as compared to that during tillering. As a result, the sugarcane crop tested was much more sensitive to water stress at stem elongation than at tillering. Therefore, deficit irrigation practice to increase crop water use efficiency might be recommended at tillering rather than stem elongation. The water management strategy to be suggested here may consist of omitting irrigation during tillering (assuming that the crop is successfully established) for the benefit of stem elongation. As far as stem elongation is concerned, a moderate water deficit of about 25% with respect to the full irrigation regime appears to increase crop water use efficiency. (author). 15 refs, 6 figs, 4 tabs.

1996-01-01

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Influence of biochar use on sugarcane growth, soil parameters, and groundwater quality  

UK PubMed Central (United Kingdom)

This study deals with the influence of biochar use on sugarcane growth and nitrate-nitrogen percolation losses, as well as chemical and physical properties of Shimajiri maji soil. Two varieties of biochars, biosolids and bagasse (residues of sugarcane stalks after juice extraction), were mixed with Shimajiri maji soil. Changes in nitrate-nitrogen concentration in percolating water, specific gravity, and available soil moisture before sugarcane planting and after harvest were investigated. Indices of sugarcane growth (stem diameter and length), Brix, and yield of estimated available sugar in each plot were estimated. Results indicated that bagasse charcoal reduced soil dry density and increased available moisture of Shimajiri maji soil. Maintaining suitable soil water content increased yields and sugar content of sugarcane, while nitrate-nitrogen concentration in percolating water also decreased. Hence, bagasse charcoal use may reduce nitrogen loads in Shimajiri maji soil.

Chen Yan; Shinogi Yoshiyuki; Taira Masahiko

2010-01-01

 
 
 
 
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Correlation of Growth Traits and Yield of Sugarcane with Micronutrients  

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Full Text Available Experiments on the correlation coefficient of growth and cane yield traits of sugarcane with micro nutrients like: Zn (1.50, 3.00 and 4.50 kg ha-1), Cu (0.5, 1.0 and 1.5 kg ha-1), B (0.25, 0.50 and 0.75 kg ha-1) and Mn (1.0, 2.0 and 3.0 kg ha-1) and control where conducted. The results revealed that all micro nutrients showed positive correlation with tillers, tope weight, cane length, internode number and length, stem diameter, hieght, millable cane and cane yield, except copper for tillers, zinc for top weight, boron for top weight and manganese responded significant response for stem diameter and millable canes, respectively. It is suggested that micro nutrients are essential elements for obtaining satisfactory yields for sugarcane. Application of excess amount of these elements reduces the yield by reducing the crop parameter values, but, adequate quantities produced boosted yield. Thus, it is recommended that micro nutrients may be applied after various soil tests and proper levels should be chalked-out.

F.C. Oad; G.H. Jamro; A.A. Lakho; G.Q. Chandio

2002-01-01

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Effects of Machine-Induced Soil Compaction on Growth and Yield of Sugarcane  

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Full Text Available Problem statement: Sugarcane is one of the main economic crops in Thailand. After planting, it can be harvested annually for several successive ratoon crops. Recently, soil compaction due to mechanization has been recognized as a serious problem in sugarcane production. Therefore, this study aimed to clarify the effects of soil compaction on the growth and yield of sugarcane. Approach: The field experiments were conducted in loamy soil using a Randomized Complete Block Design (RCBD) with four treatments of soil compaction prepared by 0, 5, 15 and 20 numbers of wheel passages of a tractor. Results: The results showed that soil compaction had significant effects on both the growth and yield of sugarcane, with the exceptions of tillering and Brix. The greatest reduction in yield compared with the control field was 22.9%, which resulted from compacting with 15 tractor passages. The influence of block or furrow irrigation was indicated by the positive effect that higher watering had on minimizing the impact of soil compaction on the growth of sugarcane. Conclusion: Effects of soil compaction on growth and yield of sugarcane were clarified to some extent.

Prathuang Usaborisut; Tanya Niyamapa

2010-01-01

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Efeito da temperatura no crescimento micelial e patogenicidade de Pythium spp. que ocorrem em alface hidropônica Temperature effects on mycelial growth and pathogenicity of Pythium spp. occuring in hydroponic lettuce  

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Full Text Available Doze isolados de Pythium foram obtidos de raízes de alface cultivada em sistemas hidropônicos comerciais, apresentando ou não sintomas de apodrecimento. Três desses isolados foram identificados como Pythium helicoides Drechsler (H1, H2 e H3), cinco como pertencentes ao grupo F (F1 a F5) e quatro ao grupo T (T1 a T4) de Pythium. A identificação das espécies foi realizada baseando-se nas características morfológicas. O efeito da temperatura (10, 15, 18, 21, 24, 27, 30, 37 e 40ºC) sobre o crescimento micelial foi determinado para todos os isolados. As temperaturas mínima e máxima, estimadas pela função beta generalizada, variaram de 3,5 a 10ºC e de 40 a 40,7ºC, respectivamente. A temperatura ótima foi de 24 a 37ºC para P. helicoides, de 25 a 35ºC para o isolado F4 e de 21 a 30ºC para os demais isolados. A patogenicidade e a agressividade dos isolados foram avaliadas, inoculando-se sementes de alface cv. Verônica, semeadas em ágar-água, a 21 e 30ºC. A 30ºC, os isolados de P. helicoides foram notadamente os mais agressivos, ocasionando 100 % de mortalidade das sementes logo após sua germinação. A 21ºC, todos os isolados induziram subdesenvolvimento de plântulas, acompanhado ou não de necrose dos tecidos radiculares. Trata-se do primeiro relato de P. helicoides para o Brasil e a primeira referência mundial da espécie em hidroponia.Twelve Pythium isolates were obtained from lettuce roots grown hydroponically in commercial systems, showing or not symptoms of rotting. Three of them were identified as P. helicoides (H1, H2 and H3), whereas five were shown to belong to group F (F1-F5) and four to group T (T1-T4) of Pythium. The identification of the species was based on morphological characteristics. The effect of temperature (10, 15, 18, 21, 24, 27, 30, 37 and 40ºC) on the mycelial growth was determined for all isolates. Minimum and maximum temperatures, estimated by the generalized beta function, varied from 3.5 to 10ºC and 40 to 40.7ºC, respectively. The optimum temperature ranged from 24 to 37ºC for P. helicoides, from 25 to 35ºC for isolate F4 and 21 to 30ºC for the remaining isolates. Pathogenicity and aggressiveness of the isolates were evaluated by the inoculation of lettuce seeds plated in water-agar, at 21 and 30ºC. At 30ºC, P. helicoides isolates were clearly the most aggressives, determining 100 % seed mortality soon after germination. At 21ºC, all isolates reduced seedling growth, associated or not with root tissue necrosis. This is the first report of P. helicoides in Brazil and the first world reference of this species in hydroponic systems.

Liliane De Diana Teixeira; Carmen Lídia Amorim Pires Zottarelli; Hiroshi Kimati

2006-01-01

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Efeito da temperatura no crescimento micelial e patogenicidade de Pythium spp. que ocorrem em alface hidropônica/ Temperature effects on mycelial growth and pathogenicity of Pythium spp. occuring in hydroponic lettuce  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese Doze isolados de Pythium foram obtidos de raízes de alface cultivada em sistemas hidropônicos comerciais, apresentando ou não sintomas de apodrecimento. Três desses isolados foram identificados como Pythium helicoides Drechsler (H1, H2 e H3), cinco como pertencentes ao grupo F (F1 a F5) e quatro ao grupo T (T1 a T4) de Pythium. A identificação das espécies foi realizada baseando-se nas características morfológicas. O efeito da temperatura (10, 15, 18, 21, 24, 27, (more) 30, 37 e 40ºC) sobre o crescimento micelial foi determinado para todos os isolados. As temperaturas mínima e máxima, estimadas pela função beta generalizada, variaram de 3,5 a 10ºC e de 40 a 40,7ºC, respectivamente. A temperatura ótima foi de 24 a 37ºC para P. helicoides, de 25 a 35ºC para o isolado F4 e de 21 a 30ºC para os demais isolados. A patogenicidade e a agressividade dos isolados foram avaliadas, inoculando-se sementes de alface cv. Verônica, semeadas em ágar-água, a 21 e 30ºC. A 30ºC, os isolados de P. helicoides foram notadamente os mais agressivos, ocasionando 100 % de mortalidade das sementes logo após sua germinação. A 21ºC, todos os isolados induziram subdesenvolvimento de plântulas, acompanhado ou não de necrose dos tecidos radiculares. Trata-se do primeiro relato de P. helicoides para o Brasil e a primeira referência mundial da espécie em hidroponia. Abstract in english Twelve Pythium isolates were obtained from lettuce roots grown hydroponically in commercial systems, showing or not symptoms of rotting. Three of them were identified as P. helicoides (H1, H2 and H3), whereas five were shown to belong to group F (F1-F5) and four to group T (T1-T4) of Pythium. The identification of the species was based on morphological characteristics. The effect of temperature (10, 15, 18, 21, 24, 27, 30, 37 and 40ºC) on the mycelial growth was determin (more) ed for all isolates. Minimum and maximum temperatures, estimated by the generalized beta function, varied from 3.5 to 10ºC and 40 to 40.7ºC, respectively. The optimum temperature ranged from 24 to 37ºC for P. helicoides, from 25 to 35ºC for isolate F4 and 21 to 30ºC for the remaining isolates. Pathogenicity and aggressiveness of the isolates were evaluated by the inoculation of lettuce seeds plated in water-agar, at 21 and 30ºC. At 30ºC, P. helicoides isolates were clearly the most aggressives, determining 100 % seed mortality soon after germination. At 21ºC, all isolates reduced seedling growth, associated or not with root tissue necrosis. This is the first report of P. helicoides in Brazil and the first world reference of this species in hydroponic systems.

Teixeira, Liliane De Diana; Zottarelli, Carmen Lídia Amorim Pires; Kimati, Hiroshi

2006-09-01

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Pythium blight of turfgrass  

Science.gov (United States)

This plant disease lesson on Pythium blight of turfgrass (caused by Pythium aphanidermatum and Pythium ultimum) includes information on symptoms and signs, pathogen biology, disease cycle and epidemiology, disease management, and the significance of the disease. Selected references are listed and a glossary is also available for use with this resource.

Tom W. Allen (University of Georgia, Griffen Campus;); Alfredo Martinez (University of Georgia, Griffen Campus;); Lee L. Burpee (University of Georgia, Griffen Campus;)

2005-01-01

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Sugarcane Response to Water-Deficit Stress during Early Growth on Organic and Sand Soils  

Directory of Open Access Journals (Sweden)

Full Text Available Problem statement: Approximately 20% of sugarcane (Saccharum spp.) is grown on sand soils in south Florida, USA. Sugarcane yields in the region linearly increased in last 33 years on organic (muck) soils, but not on sand soils. Water deficit during the formative growth phase on sand soils probably limits sugarcane yields. Approach: A greenhouse study was conducted in 2009 and 2010 to evaluate the physiological and growth responses of sugarcane to water-deficit stress during formative growth. Treatments included organic (muck) and sand soils and two water regimes Well Watered (WW) and Water-Deficit Stress (WS). Sugarcane cultivar CP 80-1743 was planted in pots and fertilized with N, P and K based on soil analyses. All pots were well watered until 58 days after planting, when water was withheld from the WS pots. During the WS treatment, plant growth rate, leaf Relative Water Content (RWC), proline content and photosynthesis components were measured. Final tillers, Green Leaf Area (GLA) and shoot biomass were determined 27 (in 2009) or 22 (in 2010) days after initiating the WS treatment. Results: Stress symptoms of sugarcane plants appeared 7-10 days earlier on sand soil than on muck soil. Water stress reduced stomatal conductance (gs), Photosystem II Photochemical Efficiency (FPSII), leaf Photosynthesis rate (Pn), the number of tillers and GLA, resulting in reduced shoot biomass, especially on sand soil. Neither leaf RWC nor proline content was a sensitive WS indicator. Conclusion: Nondestructive measurements of physiological traits of gs, FPSII and Pn during the formative stage may be useful for early detection of water stress in sugarcane.

Duli Zhao; Barry Glaz; Jack C. Comstock

2010-01-01

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Sugarcane growth promotion by the endophytic bacterium Pantoea agglomerans 33.1.  

Science.gov (United States)

The promotion of sugarcane growth by the endophytic Pantoea agglomerans strain 33.1 was studied under gnotobiotic and greenhouse conditions. The green fluorescent protein (GFP)-tagged strain P. agglomerans 33.1::pNKGFP was monitored in vitro in sugarcane plants by microscopy, reisolation, and quantitative PCR (qPCR). Using qPCR and reisolation 4 and 15 days after inoculation, we observed that GFP-tagged strains reached similar density levels both in the rhizosphere and inside the roots and aerial plant tissues. Microscopic analysis was performed at 5, 10, and 18 days after inoculation. Under greenhouse conditions, P. agglomerans 33.1-inoculated sugarcane plants presented more dry mass 30 days after inoculation. Cross-colonization was confirmed by reisolation of the GFP-tagged strain. These data demonstrate that 33.1::pNKGFP is a superior colonizer of sugarcane due to its ability to colonize a number of different plant parts. The growth promotion observed in colonized plants may be related to the ability of P. agglomerans 33.1 to synthesize indoleacetic acid and solubilize phosphate. Additionally, this strain may trigger chitinase and cellulase production by plant roots, suggesting the induction of a plant defense system. However, levels of indigenous bacterial colonization did not vary between inoculated and noninoculated sugarcane plants under greenhouse conditions, suggesting that the presence of P. agglomerans 33.1 has no effect on these communities. In this study, different techniques were used to monitor 33.1::pNKGFP during sugarcane cross-colonization, and our results suggested that this plant growth promoter could be used with other crops. The interaction between sugarcane and P. agglomerans 33.1 has important benefits that promote the plant's growth and fitness. PMID:22865062

Quecine, M C; Araújo, W L; Rossetto, P B; Ferreira, A; Tsui, S; Lacava, P T; Mondin, M; Azevedo, J L; Pizzirani-Kleiner, A A

2012-08-03

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Pythium litorale sp. nov., a new species from the littoral of Lake Constance, Germany.  

UK PubMed Central (United Kingdom)

A description is given of Pythium litorale sp. nov., a new species from reed stands in Germany. Pythium litorale was among the most abundant species when the oomycete community of littoral soils of Lake Constance was studied. It was consistently isolated from flooded as well as from drier reed sites. The species is characterized by subglobose, papillate and internally proliferating sporangia, globose hyphal swellings, the absence of oogonia in single culture and a high optimum growth temperature. It proved to be nonpathogenic to Phragmites australis, the predominating plant in the investigated sites. Molecular analysis of ribosomal DNA internal transcribed spacer regions placed Pythium litorale in a clade together with its closest relatives Pythium megacarpum, Pythium boreale, Pythium montanum and Pythium carbonicum. The generic status of this basal clade in Pythium is currently under discussion, as it possibly represents a separate genus that is distinct from Pythium, and shares several characteristics with Phytophthora.

Nechwatal J; Mendgen K

2006-02-01

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Short-term effects of sugarcane waste products from ethanol production plant as soil amendments on sugarcane growth and metal stabilization.  

UK PubMed Central (United Kingdom)

Numerous waste products have been widely studied and used as soil amendments and metal immobilizing agents. Waste utilization from ethanol production processes as soil amendments is one of the most promising and sustainable options to help utilize materials effectively, reduce waste disposal, and add value to byproducts. As a consequence, this present work carried out a four-month pot experiment of sugarcane (Saccharum officinarum L.) cultivation in Cd and Zn contaminated soil to determine the effect of three sugarcane waste products (boiler ash, filter cake and vinasse) as soil amendment on sugarcane growth, metal translocation and accumulation in sugarcane, and fractionation of Cd and Zn in soil by the BCR sequential extraction. Four treatments were tested: (1) non-amended soil; (2) 3% w/w boiler ash; (3) 3% w/w filter cake; and (4) a combination of 1.5% boiler ash and 1.5% vinasse (w/w). Our findings showed the improved biomass production of sugarcanes; 6 and 3-fold higher for the above ground parts (from 8.5 to 57.6 g per plant) and root (from 2.1 to 6.59 g per plant), respectively, as compared to non-amended soil. Although there was no significant difference in Cd and Zn uptake in sugarcane (mg kg(-1)) between the non-amended soil and the treated soils (0.44 to 0.52 mg Cd kg(-1) and 39.9 to 48.1 mg Zn kg(-1), respectively), the reduction of the most bioavailable Cd concentration (BCR1 + 2) in the treated soils (35.4-54.5%) and the transformation of metal into an insoluble fraction (BCR3) highlighted the beneficial effects of sugarcane waste-products in promoting the sugarcane growth and Cd stabilization in soil.

Akkajit P; DeSutter T; Tongcumpou C

2013-05-01

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Plant growth-promoting nitrogen-fixing enterobacteria are in association with sugarcane plants growing in Guangxi, China.  

UK PubMed Central (United Kingdom)

The current nitrogen fertilization for sugarcane production in Guangxi, the major sugarcane-producing area in China, is very high. We aim to reduce nitrogen fertilization and improve sugarcane production in Guangxi with the help of indigenous sugarcane-associated nitrogen-fixing bacteria. We initially obtained 196 fast-growing bacterial isolates associated with the main sugarcane cultivar ROC22 plants in fields using a nitrogen-deficient minimal medium and screened out 43 nitrogen-fixing isolates. Analysis of 16S rRNA gene sequences revealed that 42 of the 43 nitrogen-fixing isolates were affiliated with the genera Enterobacter and Klebsiella. Most of the nitrogen-fixing enterobacteria possessed two other plant growth-promoting activities of IAA production, siderophore production and phosphate solubilization. Two Enterobacter spp. strains of NN145S and NN143E isolated from rhizosphere soil and surface-sterilized roots, respectively, of the same ROC22 plant were used to inoculate micropropagated sugarcane plantlets. Both strains increased the biomass and nitrogen content of the sugarcane seedlings grown with nitrogen fertilization equivalent to 180 kg urea ha(-1), the recommended nitrogen fertilization for ROC22 cane crops at the seedling stage. (15)N isotope dilution assays demonstrated that biological nitrogen fixation contributed to plant growth promotion. These results suggested that indigenous nitrogen-fixing enterobacteria have the potential to fix N(2) associated with sugarcane plants grown in fields in Guangxi and to improve sugarcane production.

Lin L; Li Z; Hu C; Zhang X; Chang S; Yang L; Li Y; An Q

2012-01-01

31

Effect of Maize Population (As Intercrop) on the Growth of Ratoon Sugarcane and Maize Yield  

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The study was conducted on the effect of maize population on the growth of ratoon sugarcane and maize yield Data was recorded on different yield and yield components of maize. Maximum (164.4 cm) and minimum (133.6 cm) plant height of maize was attained with 30,000 plants ha-1. Maximum num...

Imran Haider Shamsi; Wajid Ali Shah; Jehan Bakht; Mujtaba Masood

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Hormone Dependent Growth Promotion and Growth Retardation of Sugarcane Tissue Cultures for Germplasm Conservation  

Directory of Open Access Journals (Sweden)

Full Text Available Two sugarcane (Saccharum Officinarum L) varieties namely, Katha and BL4 were used in this study in order to compare their response for culture establishment, shoot proliferation, root induction and growth retardation. Shoot number, mass and length were the growth parameters measured. Genotype dependent response was found against different growth conditions such as growth media composition and growth regulators. Liquid Murashige-Skoog (MS) media was found to be more suitable for culture proliferation as compared to the solid media of the same composition, suggesting a positive and favorable effect of aeration and homogenization on culture performance. A better organogenesis response i.e. maximum shoot length, shoot mass and shoot number was observed when explants were cultured on the media containing 4.4 ?M BAP for both the varieties but BL4 appeared to be more responsive genotype to shoot proliferation as compared to katha at any given level of growth regulator. Growth retardation was best achieved on the media containing 4 g L -1 mannitol among the concentrations used and degree of growth retardation was also found to be genotype dependent. There was a linear relationship between degree of growth retardation and concentration of the osmotica used. Root induction response (root number and root length) was the highest in katha cultures grown on half strength MS media containing 1.9 ?M Indole butyric acid among the auxins, Indol butyric acid, indole acetic acid and naphthalene acetic acid, that were used in this study.

Saira Pervaiz; Ghulam Mustafa Sajid; Rashid Anwer; Hidayat-ur-Rahman

2005-01-01

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Quantitative relationships of Pseudomonas chlororaphis 63-28 to Pythium root rot and growth in hydroponic peppers Relações quantitativas de Pseudomonas chlororaphis 63-28 com a podridão radicular causada por Pythium e ao crescimento de pimentão hidropônico  

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Full Text Available The ability of Pseudomonas chlororaphis 63-28 to suppress Pythium root rot (Pythium aphanidermatum) and promote plant growth was investigated in hydroponic peppers that were predisposed or not predisposed to the disease. The biocontrol agent was introduced into the nutrient solution 10 days before the roots were inoculated with the pathogen. The root zone was maintained at 23ºC except when roots were exposed to 33ºC for three days before inoculation to induce predisposition to root rot. At constant 23ºC (no predisposition) application of P. chlororaphis at 10(7) CFU mL-1 nutrient solution delayed root browning more effectively than did higher or lower densities. In predisposed plants, densities of 10(6), 10(7) and 10(8) CFU mL-1 were equally superior. When applied at 10(7) CFU mL-1, the density of P. chlororaphis on roots of the two temperature regimes ranged from log10 5.88 to 6.45 CFU g-1 fresh roots at seven to 19 days after application. The agent delayed root browning, re-mediated predisposition to root rot, and increased growth of inoculated and non-inoculated plants. Leaf expansion was a sensitive marker of root rot and remediation by P. chlororaphis. We conclude that P. chlororaphis 63-28 has substantial potential for managing the disease regardless of predisposition.A supressão da podridão de raiz (Pythium aphanidermatum) e a promoção de crescimento de pimentão hidropônico por Pseudomonas chlororaphis 63-28 foram avaliadas em plantas predispostas ou não ao patógeno. O bioagente foi introduzido na solução nutritiva 10 dias antes das raízes serem inoculadas com o patógeno. A zona radicular foi mantida a 23ºC, exceto nos três dias antes da inoculação quando as plantas foram expostas a 33ºC. Na temperatura de 23ºC (sem predisposição), P. chlororaphis na concentração de 10(7) UFC mL-1, aplicada na solução nutritiva, atrasou o aparecimento dos sintomas da doença. As concentrações de 10(6), 10(7) e 10(8) UFC mL-1 do bioagente foram mais eficientes em controlar a doença nas plantas inoculadas com o patógeno. A densidade do bioagente nas raízes, nos dois regimes de temperatura, variou de 5,88 a 6,45 log da UFC g-1 de raiz fresca, do sétimo ao 19º dia após a aplicação de 10(7) UFC mL-1 Nas plantas inoculadas ou não, o bioagente atrasou o aparecimento do escurecimento radicular, remediou a predisposição a doença e incrementou o desenvolvimento das plantas. A expansão foliar foi um indicador adequado para a podridão de raiz e a remediação com P. chlororaphis. Conclui-se que P. chlororaphis 63-28 tem potencial para o manejo da podridão da raiz em sistemas hidropônicos, independentemente da predisposição.

Coralie R. Sopher; John C. Sutton

2011-01-01

34

Quantitative relationships of Pseudomonas chlororaphis 63-28 to Pythium root rot and growth in hydroponic peppers/ Relações quantitativas de Pseudomonas chlororaphis 63-28 com a podridão radicular causada por Pythium e ao crescimento de pimentão hidropônico  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese A supressão da podridão de raiz (Pythium aphanidermatum) e a promoção de crescimento de pimentão hidropônico por Pseudomonas chlororaphis 63-28 foram avaliadas em plantas predispostas ou não ao patógeno. O bioagente foi introduzido na solução nutritiva 10 dias antes das raízes serem inoculadas com o patógeno. A zona radicular foi mantida a 23ºC, exceto nos três dias antes da inoculação quando as plantas foram expostas a 33ºC. Na temperatura de 23ºC (sem (more) predisposição), P. chlororaphis na concentração de 10(7) UFC mL-1, aplicada na solução nutritiva, atrasou o aparecimento dos sintomas da doença. As concentrações de 10(6), 10(7) e 10(8) UFC mL-1 do bioagente foram mais eficientes em controlar a doença nas plantas inoculadas com o patógeno. A densidade do bioagente nas raízes, nos dois regimes de temperatura, variou de 5,88 a 6,45 log da UFC g-1 de raiz fresca, do sétimo ao 19º dia após a aplicação de 10(7) UFC mL-1 Nas plantas inoculadas ou não, o bioagente atrasou o aparecimento do escurecimento radicular, remediou a predisposição a doença e incrementou o desenvolvimento das plantas. A expansão foliar foi um indicador adequado para a podridão de raiz e a remediação com P. chlororaphis. Conclui-se que P. chlororaphis 63-28 tem potencial para o manejo da podridão da raiz em sistemas hidropônicos, independentemente da predisposição. Abstract in english The ability of Pseudomonas chlororaphis 63-28 to suppress Pythium root rot (Pythium aphanidermatum) and promote plant growth was investigated in hydroponic peppers that were predisposed or not predisposed to the disease. The biocontrol agent was introduced into the nutrient solution 10 days before the roots were inoculated with the pathogen. The root zone was maintained at 23ºC except when roots were exposed to 33ºC for three days before inoculation to induce predisposi (more) tion to root rot. At constant 23ºC (no predisposition) application of P. chlororaphis at 10(7) CFU mL-1 nutrient solution delayed root browning more effectively than did higher or lower densities. In predisposed plants, densities of 10(6), 10(7) and 10(8) CFU mL-1 were equally superior. When applied at 10(7) CFU mL-1, the density of P. chlororaphis on roots of the two temperature regimes ranged from log10 5.88 to 6.45 CFU g-1 fresh roots at seven to 19 days after application. The agent delayed root browning, re-mediated predisposition to root rot, and increased growth of inoculated and non-inoculated plants. Leaf expansion was a sensitive marker of root rot and remediation by P. chlororaphis. We conclude that P. chlororaphis 63-28 has substantial potential for managing the disease regardless of predisposition.

Sopher, Coralie R.; Sutton, John C.

2011-08-01

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Sterols and the Sensitivity of Pythium Species to Filipin1  

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Schlosser, Eckart (University of Illinois, Urbana), and David Gottlieb. Sterols and the sensitivity of Pythium species to filipin. J. Bacteriol. 91:1080–1084. 1966.—The growth of several Pythium species was not affected by filipin. No leakage of inorganic phosphate was observed after treatment with ...

Schlosser, Eckart; Gottlieb, David

36

White-rot fungal growth on sugarcane lignocellulosic residue  

Energy Technology Data Exchange (ETDEWEB)

Twelve white-rot fungi were grown in solid state culture on sugarcane chips previously fermented by yeast employing the EX-FERM process. The lignocellulosic sugarcane residue had 12.5% permanganate lignin and 81.3% holocellulose. After 5 to 6 weeks at 20/sup 0/C, all fungi produced a solid residue which had a lower in vitro dry matter enzymatic digestibility than the original bagasse, with the exception of Coriolus versicolor which showed a slight increase of 0.6 units. Four fungi produced a residue with higher soluble solids that the original sample. Lignin losses were rather similar for all fungi tested, an average value of 38.64% of the original value was obtained. About the same amount of hemicellulose was degreaded, 32.22%. Most fungi showed a preference for hemicellulose hydrolysis over cellulose degradation. The two fungi that showed greater cellulolytic activity were Sporotrichum pulverulentum and Dichomitus squalens. No appreciable dry matter losses were detected for Agrocybe aergerita and Flammulina velutipes.

Rolz, C.; Leon, R. de; Arriola, M.C. de; Cabrera, S. de

1987-03-01

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The Selection of Sugarcane Families That Display Better Associations with Plant Growth Promoting Rhizobacteria  

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Full Text Available The capacity of the sugarcane plant to respond to Plant Growth Promoting Rhizobacteria (PGPR) is associated with both the efficiency of the bacterial strain and the capacity of the plant to respond to inoculation. For this reason, the appropriate selection of both the bacterial strain and the sugarcane genotype is required for generating optimal results from PGPR inoculations. To address this issue, this study sought to evaluate the response of 54 sugarcane families to inoculation with Azospirillum brasilense strains. In particular, four months after germination, 54 families from crosses between clones of sugarcane were treated either with an inoculant named Triazo, which was composed of a mixture of the Abv5, Abv6 and Abv7 strains of A. brasilense, or with the IC26 strain of A. brasilense. The treated plants were then planted in fields. These plants were assessed 14 months after they had been planted on the basis of various productivity parameters. Significant differences among the inoculants were observed for stalk length, stalk diameter and Brix. Significant interactions between the families and bacteria occurred with respect to stalk diameter and Brix; the interaction coefficients could have either positive (0.7272 for Brix and 0.4061 for stalk diameter) or negative (-0.5514 for Brix and -0.1858 for stalk diameter) values, depending on the family and the inoculant that were considered. Therefore, the inoculation of the seedling in the first phase of selection is recommended for a sugarcane breeding program that seeks to select genotypes with better responses to PGPR inoculation.

Valeria Rosa Lopes; Joao C. Bespalhok-Filho; Luiza Maria de Araujo; Fabio Vieira Rodrigues; Edelclaiton Daros; Ricardo Augusto Oliveira

2012-01-01

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The effect of crop residue layers on evapotranspiration, growth and yield of irrigated sugarcane  

Scientific Electronic Library Online (English)

Full Text Available Abstract in english A layer of harvest residues from the previous crop can reduce wasteful evaporation from the soil surface and thereby increase the efficiency of use of limited water resources for agricultural production. The practice of harvesting sugarcane green and leaving crop residues in the field, as opposed to burning the residue, has been re-adopted in many sugarcane industries worldwide. However, a better understanding of the dynamic impacts of residue layers on various aspects of (more) the cropping system is required to (1) enable the formulation of sets of best management practices for specific production scenarios, and (2) promote the use of residue layers in areas where it is desirable and has not been adopted, such as irrigated sugarcane production in South Africa. The objective of this study, therefore, was to quantify the effect of 2 different types of residue layers on crop growth, cane yield and evapotranspiration of fully irrigated sugarcane. A layer of cane tops and dead leaves (Trash) and a layer of green tops (Tops) were applied to the soil surface of sugarcane crops (plant crop and first ratoon crop of variety N14) grown on lysimeters at Pongola, South Africa. Observations of crop growth (stalk population, stalk height, canopy cover), cane yield and evapotranspiration for these treatments were compared to that of a bare soil treatment. The data were also used to derive values of crop evaporation coefficients for different development phases and these were compared to FAO56 recommendations. Initial stalk population in the plant crop and radiation capture in the plant and ratoon crop were affected negatively by crop residue layers, but without significantly reducing final stalk population and cane yield. Peak stalk population occurred later in crops grown in residue layers, but peak and final stalk populations were unaffected. Evapotranspiration was reduced by both residue layers, mainly due to a slower developing canopy (reduced transpiration) and reduced evaporation from the soil, during the pre-canopy phases. Increased drainage was observed under residue layers, emphasising the importance of accurate irrigation scheduling to avoid water logging. The FAO56 methodology for calculating crop evaporation coefficient values for the initial, development and late season phases are supported by the results obtained here. Crop evaporation coefficient values were significantly reduced by residue layers. It is important that irrigation scheduling practices be adjusted to realise the potential water savings of sugarcane production systems that make use of residue layers. This study provides the information required to do that. The information could also be used to improve the ability of the crop models to accurately simulate crop growth and evapotranspiration in a residue layer cropping system.

Olivier, FC; Singels, A

2012-01-01

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Effect of Foliar Application of Micro Nutrients on the Growth Traits of Sugarcane Variety Cp-65/357 (Ratoon Crop)  

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Full Text Available Field experiments were conducted to asses the effect of different micro nutrients on the growth traits of sugarcane variety CP-65/357 (Ratoon crop) on silt loam soils at Sugarcane Crops Research Institute, Mardan, Pakistan. It was observed that application of micro nutrients significantly affected all the growth traits of sugarcane variety CP-65/357, whereas plant height, tops weight, cane length, internodes and length of internodes were significantly increased by the application of all the micro nutrients over the control. The average plant height, tops weight, cane length, number of internodes and length of internodes of ratoon crop were maximized by the lowest rates of Zn and Cu. Furthermore data revealed that the highest rates of B and Mn increased all the growth traits in comparison to their lowest rates.

G. H. Jamro; B. R. Kazi; F. C. Oad; N. M. Jamali; N. L. Oad

2002-01-01

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In vitro incorporation of 1-14C-acetate and 32P-orthophosphoric acid into phospholipids at various stages of growth of Pythium irregulare  

International Nuclear Information System (INIS)

Pythium irregulare showed an increase (11.6 to 38.9%) in total lipids and a simultaneous decrease (40.5 to 7.3%) in phospholipid content of total lipids during growth period of 15 days. Incubation of fungus of different ages viz. 2,3,4,5,7,9,11,13 and 15 days old with 32P-orthophosphoric acid for 4 hr showed that the specific activity of mycelium was maximum with the 5-days old fungus. Highest content of total and polar lipids was, however observed with the 3 days old sample. Incubation studies with sodium acetate 1-14C with fungus of various stages of growth showed maxima of specific activity in mycelium, total, polar and non-polar lipids on the 5th day. From specific activity estimation of 32P and 14C in each of the phosphatides, it was concluded that the labels were incorporated at a higher rate into phosphatidyl enthanolamine during early stages of growth. The reverse was true for the later period of growth, indicating that phosphatidyl ethanolamine was possibly converted to phosphatidyl choline. (auth.).

1979-01-01

 
 
 
 
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Controle biológico da podridão radicular (Pythium aphanidermatum) e promoção de crescimento por Pseudomonas chlororaphis 63-28 e Bacillus subtilis GB03 em alface hidropônica Biocontrol of root rot (Pythium aphanidermatum) and growth promotion with Pseudomonas chlororaphis 63-28 and Bacillus subtilis GB03 in hydroponic lettuce  

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Full Text Available Podridões radiculares causadas por espécies de Pythium são um importante problema em cultivos hidropônicos. Sintomas de subdesenvolvimento são observados nas plantas parasitadas pelo patógeno, sendo muitas vezes não diagnosticados pelo produtor. O objetivo do trabalho foi avaliar o controle biológico da podridão radicular causada por Pythium aphanidermatum e a promoção de crescimento por Pseudomonas chlororaphis 63-28 e Bacillus subtilis GB03, reconhecidos agentes de controle biológico de doenças de plantas. A inoculação das plantas com P. aphanidermatum ocasionou o subdesenvolvimento, sendo essa diminuição de 20%. A adição dos agentes de biocontrole na solução nutritiva teve um efeito positivo no aumento da massa (6% a 13%), no número de folhas (4% a 7%) e no teor de clorofila (3%) das plantas de alface. Entretanto, maiores estudos devem ser realizados para melhorar a capacidade de controle da doença e de promoção de crescimento pelos agentes de biocontrole estudados no cultivo de alface hidropônica.Root rot caused by Pythium species is a major problem in hydroponically-grown crops. Symptoms of canopy stunting are noticed in plants colonized by the pathogen and many times they are not diagnosed by the grower. The aim of this work was to evaluate biological control and plant growth promotion by Pseudomonas chlororaphis 63-28 and Bacillus subtilis GB03, known biocontrol agents of plant diseases. Inoculation of plants with P. aphanidermatum decreased lettuce mass by 20%. The introduction of the biocontrol agents to the nutrient solution was beneficial for plant growth increasing the plant mass (6% to 13%), the number of leaves (4% to 7%) and the chlorophyll content (3%) of the lettuce plants. Further studies are needed, however, to improve the effectiveness of disease control and growth promotion by the biological agents in hydroponic lettuce.

Élida Barbosa Corrêa; Wagner Bettiol; John Clifford Sutton

2010-01-01

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Controle biológico da podridão radicular (Pythium aphanidermatum) e promoção de crescimento por Pseudomonas chlororaphis 63-28 e Bacillus subtilis GB03 em alface hidropônica/ Biocontrol of root rot (Pythium aphanidermatum) and growth promotion with Pseudomonas chlororaphis 63-28 and Bacillus subtilis GB03 in hydroponic lettuce  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese Podridões radiculares causadas por espécies de Pythium são um importante problema em cultivos hidropônicos. Sintomas de subdesenvolvimento são observados nas plantas parasitadas pelo patógeno, sendo muitas vezes não diagnosticados pelo produtor. O objetivo do trabalho foi avaliar o controle biológico da podridão radicular causada por Pythium aphanidermatum e a promoção de crescimento por Pseudomonas chlororaphis 63-28 e Bacillus subtilis GB03, reconhecidos agen (more) tes de controle biológico de doenças de plantas. A inoculação das plantas com P. aphanidermatum ocasionou o subdesenvolvimento, sendo essa diminuição de 20%. A adição dos agentes de biocontrole na solução nutritiva teve um efeito positivo no aumento da massa (6% a 13%), no número de folhas (4% a 7%) e no teor de clorofila (3%) das plantas de alface. Entretanto, maiores estudos devem ser realizados para melhorar a capacidade de controle da doença e de promoção de crescimento pelos agentes de biocontrole estudados no cultivo de alface hidropônica. Abstract in english Root rot caused by Pythium species is a major problem in hydroponically-grown crops. Symptoms of canopy stunting are noticed in plants colonized by the pathogen and many times they are not diagnosed by the grower. The aim of this work was to evaluate biological control and plant growth promotion by Pseudomonas chlororaphis 63-28 and Bacillus subtilis GB03, known biocontrol agents of plant diseases. Inoculation of plants with P. aphanidermatum decreased lettuce mass by 20% (more) . The introduction of the biocontrol agents to the nutrient solution was beneficial for plant growth increasing the plant mass (6% to 13%), the number of leaves (4% to 7%) and the chlorophyll content (3%) of the lettuce plants. Further studies are needed, however, to improve the effectiveness of disease control and growth promotion by the biological agents in hydroponic lettuce.

Corrêa, Élida Barbosa; Bettiol, Wagner; Sutton, John Clifford

2010-12-01

43

Pythium insidiosum: An overview  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Pythium insidiosum is an oomycete pathogenic in mammals. The infection occurs mainly in tropical and subtropical areas, particularly in horses, dogs and humans. Infection is acquired through small wounds via contact with water that contains motile zoospores or other propagules (zoospores or hyphae)....

Gaastra, W.; Lipman, L.J.A.; De Cock, A.W.; Exel, T.K.; Pegge, R.B.; Scheurwater, J.; Vilela, R.; Mendoza, L.

44

Pythium insidiosum: An overview  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Pythium insidiosum is an oomycete pathogenic in mammals. The infection occurs mainly in tropical and subtropical areas, particularly in horses, dogs and humans. Infection is acquired through small wounds via contact with water that contains motile zoospores or other propagules (zoos...

45

Diversity and plant growth promoting evaluation abilities of bacteria isolated from sugarcane cultivated in the South of Brazil  

UK PubMed Central (United Kingdom)

Plant growth promoting (PGP) bacteria associated with sugarcane are a promising alternative for the expansion of this crop in Southern Brazil. In this study bacterial strains from different sugarcane fields were isolated to estimate their diversity, to evaluate some of their PGP activities and to use them as inoculant strains in field experiment. Samples of rhizospheric soil, roots, and stems of sugarcane were collected in six Rio Grande do Sul localities. The isolation of bacteria was made in three different N-free media. DNA from each isolate was subjected to nifH or 16S rDNA PCR-RFLP, and to the 16S rDNA partial sequencing. Five hundred and sixteen strains were isolated and several PGP characteristics were analyzed. Shannon index was used to evaluate the bacterial diversity. Indexes varying from 0.94 to 2.46 were obtained. Soil pH and clay were the characteristics most closely related to bacterial diversity. Achromobacter, Agrobacterium, Burkholderia, Gluconacetobacter, and Stenotrophomonas were the most abundant genera. Concerning the PGP activities, indolic compounds production was detected in 368 isolates; 138 isolates were able to solubilize phosphate; and 390 were siderophores producers. The inoculation of sugarcane with Gluconacetobacter diazotrophicus VI27 strain showed a significant increase in the number of sets germinated, in the amount of soluble solids, and in the yield of sugarcane juice compared with the control. As a conclusion, a diverse population of PGP bacteria was found in the sugarcane samples. These bacteria, especially G. diazotrophicus strain VI27, could be used as biofertilizers of sugarcane as well as other cereal crops under controlled conditions to avoid or reduce the use of standard N fertilizers.

Beneduzi A; Moreira F; Costa PB; Vargas LK; Lisboa BB; Favreto R; Baldani JI; Passaglia LMP

2013-01-01

46

Quantitative proteomic analysis of the interaction between the endophytic plant-growth-promoting bacterium Gluconacetobacter diazotrophicus and sugarcane.  

UK PubMed Central (United Kingdom)

Gluconacetobacter diazotrophicus is a plant-growth-promoting bacterium that colonizes sugarcane. In order to investigate molecular aspects of the G. diazotrophicus-sugarcane interaction, we performed a quantitative mass spectrometry-based proteomic analysis by (15)N metabolic labeling of bacteria, root samples, and co-cultures. Overall, more than 400 proteins were analyzed and 78 were differentially expressed between the plant-bacterium interaction model and control cultures. A comparative analysis of the G. diazotrophicus in interaction with two distinct genotypes of sugarcane, SP70-1143 and Chunee, revealed proteins with fundamental roles in cellular recognition. G. diazotrophicus presented proteins involved in adaptation to atypical conditions and signaling systems during the interaction with both genotypes. However, SP70-1143 and Chunee, sugarcane genotypes with high and low contribution of biological nitrogen fixation, showed divergent responses in contact with G. diazotrophicus. The SP70-1143 genotype overexpressed proteins from signaling cascades and one from a lipid metabolism pathway, whereas Chunee differentially synthesized proteins involved in chromatin remodeling and protein degradation pathways. In addition, we have identified 30 bacterial proteins in the roots of the plant samples; from those, nine were specifically induced by plant signals. This is the first quantitative proteomic analysis of a bacterium-plant interaction, which generated insights into early signaling of the G. diazotrophicus-sugarcane interaction.

Lery LM; Hemerly AS; Nogueira EM; von Krüger WM; Bisch PM

2011-05-01

47

Quantitative proteomic analysis of the interaction between the endophytic plant-growth-promoting bacterium Gluconacetobacter diazotrophicus and sugarcane.  

Science.gov (United States)

Gluconacetobacter diazotrophicus is a plant-growth-promoting bacterium that colonizes sugarcane. In order to investigate molecular aspects of the G. diazotrophicus-sugarcane interaction, we performed a quantitative mass spectrometry-based proteomic analysis by (15)N metabolic labeling of bacteria, root samples, and co-cultures. Overall, more than 400 proteins were analyzed and 78 were differentially expressed between the plant-bacterium interaction model and control cultures. A comparative analysis of the G. diazotrophicus in interaction with two distinct genotypes of sugarcane, SP70-1143 and Chunee, revealed proteins with fundamental roles in cellular recognition. G. diazotrophicus presented proteins involved in adaptation to atypical conditions and signaling systems during the interaction with both genotypes. However, SP70-1143 and Chunee, sugarcane genotypes with high and low contribution of biological nitrogen fixation, showed divergent responses in contact with G. diazotrophicus. The SP70-1143 genotype overexpressed proteins from signaling cascades and one from a lipid metabolism pathway, whereas Chunee differentially synthesized proteins involved in chromatin remodeling and protein degradation pathways. In addition, we have identified 30 bacterial proteins in the roots of the plant samples; from those, nine were specifically induced by plant signals. This is the first quantitative proteomic analysis of a bacterium-plant interaction, which generated insights into early signaling of the G. diazotrophicus-sugarcane interaction. PMID:21190439

Lery, Letícia M S; Hemerly, Adriana S; Nogueira, Eduardo M; von Krüger, Wanda M A; Bisch, Paulo M

2011-05-01

48

Effect of Maize Population (As Intercrop) on the Growth of Ratoon Sugarcane and Maize Yield  

Directory of Open Access Journals (Sweden)

Full Text Available The study was conducted on the effect of maize population on the growth of ratoon sugarcane and maize yield Data was recorded on different yield and yield components of maize. Maximum (164.4 cm) and minimum (133.6 cm) plant height of maize was attained with 30,000 plants ha-1. Maximum number of (10.73 leaves plant-1), cob length (19.2 cm) and grains cob-1 (205.2) were recorded with 30,000 maize population ha-1. While maximum barrenness of 18.90 was observed in plots containing maximum maize population of 60,000 plants ha-1. Maximum grain weight (240 g), grain yield (2400 kg ha-1) and harvest index (15.45) were recorded with lowest maize population of 30,000 plants ha-1, while maximum (7.2) and minimum (4.5 kg) biological yield unit area-1 were recorded in 30,000 and 60,000 plant population of maize ha-1 respectively, maximum number of shoots stump-1 were 8.91, 11.33 and 12.08 with 30,000 plant population of maize ha-1, while minimum 0.57 were observed in 30,000 maize population ha-1, respectively. Maximum of 68.88 and minimum of 59.02 cm sugarcane heights at maize harvest were recorded with 30,000 and 60,000 maize population ha-1, respectively.

Imran Haider Shamsi; Wajid Ali Shah; Jehan Bakht; Mujtaba Masood

2003-01-01

49

Some patterns of herbicide and growth regulator intake, persistence, and distribution in sugarcane.  

Science.gov (United States)

Absorption of 14C-labeled herbicides from nutrient culture solution through the roots of sugarcane plants (Saccharum spp. hybrids) resulted in three major types of distribution. Labeled residues from atrazine, ametryne, and metribuzine moved easily through the xylem to the green leaves and were deposited mainly at the leaf margins and tip. Senescence and leaf abscission removed most of the deposit from the plant. Picloram translocated rapidly into the leaves, but appeared to recycle from older to younger leaves with only small portions remaining in the senescent leaves. Asulam and pentachlorophenol (PCP) were absorbed by the roots; residues did not pass into the xylem and remained fixed in the roots. Foliar additions of labeled herbicides and growth regulators generally showed only minor absorption and translocation within the leaf. Weathering processes and volatility during a 6- to 12-week period left variable amounts of residue, characteristic of individual compounds, absorbed at the treated sites. PMID:999331

Hilton, H W; Nomura, N S; Kameda, S S; Yauger, W L

1976-01-01

50

Some patterns of herbicide and growth regulator intake, persistence, and distribution in sugarcane.  

UK PubMed Central (United Kingdom)

Absorption of 14C-labeled herbicides from nutrient culture solution through the roots of sugarcane plants (Saccharum spp. hybrids) resulted in three major types of distribution. Labeled residues from atrazine, ametryne, and metribuzine moved easily through the xylem to the green leaves and were deposited mainly at the leaf margins and tip. Senescence and leaf abscission removed most of the deposit from the plant. Picloram translocated rapidly into the leaves, but appeared to recycle from older to younger leaves with only small portions remaining in the senescent leaves. Asulam and pentachlorophenol (PCP) were absorbed by the roots; residues did not pass into the xylem and remained fixed in the roots. Foliar additions of labeled herbicides and growth regulators generally showed only minor absorption and translocation within the leaf. Weathering processes and volatility during a 6- to 12-week period left variable amounts of residue, characteristic of individual compounds, absorbed at the treated sites.

Hilton HW; Nomura NS; Kameda SS; Yauger WL

1976-01-01

51

Phytophthora and Pythium species associated with root rot of young apple trees and their control.  

UK PubMed Central (United Kingdom)

Six species of Phytophthora, two species of Pythium and five species of Fusarium were tested for pathogenicity to McIntosh apple seedlings under greenhouse conditions. Phytophthora cactorum, P. cambivora and Pythium ultimum were pathogenic, causing root rot of McIntosh apple seedlings grown in artificially-infested potting soil in greenhouse tests. Captafol inhibited the growth of most of the species of Phytophthora, Pythium and Fusarium examined in laboratory tests. Metalaxyl inhibited the growth of species of Phytophthora and Pythium but not of species of Fusarium, whereas fosetyl-Al was effective in inhibiting the growth of the three genera tested. Metalaxyl was fungicidal to Pythium ultimum and fungistatic to P. cactorum and P. cambivora, whereas fosetyl-Al was fungicidal to all Phytophthora species and fungistatic to Pythium ultimum. Enterobacter aerogenes was fungicidal to P. cactorum and fungistatic to P. cambivora and Pythium ultimum. Metalaxyl alone or in combination with thiabendazole, as well as E. aerogenes alone controlled root rot on McIntosh apple seedlings caused by P. cactorum, P. cambivora and Pythium ultimum under greenhouse conditions.

Utkhede RS; Smith EM

1991-01-01

52

Weed-crop competition effects on growth and yield of sugarcane planted using two methods  

International Nuclear Information System (INIS)

Effect of planting techniques and weed-crop competition periods on yield potential of spring planted sugarcane variety HSF-240 was studied at the Ayub Agricultural Research Institute, Faisalabad, Pakistan. The experiment was laid out in RCBD with a split-plot arrangement, with four replications and net plot size of 3.6m x 10m. In the experiment, two planting techniques viz., 60 cm apart rows in flat sowing technique and 120 cm apart rows in trench sowing technique were randomized in main plots. Seven weed-crop competition periods viz., Zero (weed free), weed-crop competition for 45, 60, 75, 90, 105 days after sowing (DAS) and weedy check (full season weed-crop competition) were randomized in sub-plots. Sugarcane sown by trench method exhibited more leaf area index (LAI), average crop growth rate (ACGR) and yield contributing attributes. Trench sowing by yielding 72.22 and 75.08 t ha/sup -1/ stripped cane yields, significantly showed superiority over the flat sowing, which gave 64.13 and 66.04 t ha/sup -1/ stripped cane yields in 2005-06 and 2006- 07, respectively. Generally, there was an increase in weed population and biomass but decrease in leaf area index, crop growth rate and yield components with an increase in weed-crop competition period. A decrease of 10.06, 17.90, 22.42, 28.65, 37.64 and 56.89% in stripped cane yield was observed for weed-crop competition periods of 45, 60, 75, 90, 105 DAS and weedy check as compared with zero competition in 2005-06, respectively. In 2006-07, the respective decrease in stripped cane yield was 9.84, 18.76, 22.92, 27.98, 38.75, and 54.98%. Trench sowing at 1.2 m row spacing proved better sowing technique and 45 DAS was the critical period of weed-crop competition. (author)

2010-01-01

53

Avaliação patogênica in vitro de Pythium middletonii Sparrow e Pythium dissotocum Drechsler em alface In vitro pathogenic evaluation of Pythium middletonii Sparrow and Pythium dissotocum Drechsler in lettuce  

Directory of Open Access Journals (Sweden)

Full Text Available Infecções radiculares nos cultivos hidropônicos de alface são frequentes e, na maior parte das vezes, causadas por espécies de Pythium, extremamente bem adaptadas ao ambiente aquático. Este estudo buscou avaliar o potencial patogênico in vitro de Pythium middletonii e P. dissotocum, em quatro cultivares de alface: Elisa (lisa), Vera (crespa), Mimosa (mimosa) e Tainá (americana). Sementes de alface, de cada cultivar, foram desinfetadas superficialmente, pré-germinadas por 24 horas, e colocadas na superfície do meio ágar-água. Em seguida, um disco de micélio dos isolados de Pythium, foi disposto no centro de cada placa. Placas contendo apenas as sementes de alface serviram como controle. O delineamento experimental utilizado foi inteiramente casualizado, com cinco repetições, sendo cada uma delas representada por uma placa de Petri. Avaliou-se o comprimento dos hipocótilos, das radículas e a porcentagem das plântulas sobreviventes após dez dias de incubação. O experimento foi conduzido na temperatura ideal de crescimento da alface (20ºC), e nas ideais para o crescimento dos isolados, 23ºC para P. middletonii e 27ºC para P. dissotocum. A 20ºC, P. dissotocum foi mais patogênico que P. middletonii, reduzindo significativamente o comprimento dos hipocótilos e, principalmente, das radículas, de praticamente todas as cultivares. Na temperatura de 27ºC, P. dissotocum foi responsável pela mais baixa porcentagem de plântulas sobreviventes entre as cultivares, sendo mais patogênico em Vera (54% de sobrevivência). Dentre as cultivares analisadas, a Mimosa mostrou tendência de menor suscetibilidade a este patógeno, apresentando a maior porcentagem de plântulas sobreviventes e o maior comprimento das radículas em relação ao controle. P. dissotocum apresentou maior crescimento micelial e foi mais patogênico que P. middletonii em todos os experimentos realizados.Root infections in hydroponic lettuce are frequent and mostly caused by Pythium species, which are extremely well adapted to aquatic environments. The present study aimed to evaluate in vitro the pathogenic potential of Pythium middletonii and Pythium dissotocum in four cultivars of lettuce, Elisa (smooth), Vera (curly), Mimosa (mimosa) and Tainá (American). Lettuce seeds from each cultivar were superficially disinfected, pre-germinated for 24 hours and placed on the water agar medium surface. Then, a dish containing mycelium from Pythium isolates was placed in the center of each plate. Control consisted of plates containing lettuce seeds only. Experimental design was completely randomized, with five replicates, each one represented by a Petri dish. Hypocotyl and radical length besides surviving seedlings percentage after ten days of incubation were evaluated. The experiment was carried out, at different temperatures, and the pathogenicity of the isolates was investigated at the ideal temperature for the lettuce (20ºC), and at the ideal temperatures for the growth of the isolates, 23ºC for P. middletonii and 27ºC for P. dissotocum. At 20ºC, P. dissotocum had higher pathogenicity on lettuce cultivars than P. middletonii, significantly decreasing the length of hypocotyls, especially radicles, of most cultivars. For P. dissotocum, 27ºC was the most suitable temperature for the specimen growth; however, it led to the lowest percentage of surviving seedlings among all cultivars, with the lowest percentage (54%) detected for Vera. Among the cultivars, Mimosa presented higher percentage of survivor seedlings and higher length of radicles in relation to the control, and thus was considered less susceptible to the pathogen. P. dissotocum presented higher mycelium growth and was more pathogenic than P. middletonii in all experiments.

F.R. Baptista; C.L.A Pires-Zottarelli; L.D. Teixeira; N.A. Santos Júnior

2011-01-01

54

Avaliação patogênica in vitro de Pythium middletonii Sparrow e Pythium dissotocum Drechsler em alface/ In vitro pathogenic evaluation of Pythium middletonii Sparrow and Pythium dissotocum Drechsler in lettuce  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese Infecções radiculares nos cultivos hidropônicos de alface são frequentes e, na maior parte das vezes, causadas por espécies de Pythium, extremamente bem adaptadas ao ambiente aquático. Este estudo buscou avaliar o potencial patogênico in vitro de Pythium middletonii e P. dissotocum, em quatro cultivares de alface: Elisa (lisa), Vera (crespa), Mimosa (mimosa) e Tainá (americana). Sementes de alface, de cada cultivar, foram desinfetadas superficialmente, pré-germin (more) adas por 24 horas, e colocadas na superfície do meio ágar-água. Em seguida, um disco de micélio dos isolados de Pythium, foi disposto no centro de cada placa. Placas contendo apenas as sementes de alface serviram como controle. O delineamento experimental utilizado foi inteiramente casualizado, com cinco repetições, sendo cada uma delas representada por uma placa de Petri. Avaliou-se o comprimento dos hipocótilos, das radículas e a porcentagem das plântulas sobreviventes após dez dias de incubação. O experimento foi conduzido na temperatura ideal de crescimento da alface (20ºC), e nas ideais para o crescimento dos isolados, 23ºC para P. middletonii e 27ºC para P. dissotocum. A 20ºC, P. dissotocum foi mais patogênico que P. middletonii, reduzindo significativamente o comprimento dos hipocótilos e, principalmente, das radículas, de praticamente todas as cultivares. Na temperatura de 27ºC, P. dissotocum foi responsável pela mais baixa porcentagem de plântulas sobreviventes entre as cultivares, sendo mais patogênico em Vera (54% de sobrevivência). Dentre as cultivares analisadas, a Mimosa mostrou tendência de menor suscetibilidade a este patógeno, apresentando a maior porcentagem de plântulas sobreviventes e o maior comprimento das radículas em relação ao controle. P. dissotocum apresentou maior crescimento micelial e foi mais patogênico que P. middletonii em todos os experimentos realizados. Abstract in english Root infections in hydroponic lettuce are frequent and mostly caused by Pythium species, which are extremely well adapted to aquatic environments. The present study aimed to evaluate in vitro the pathogenic potential of Pythium middletonii and Pythium dissotocum in four cultivars of lettuce, Elisa (smooth), Vera (curly), Mimosa (mimosa) and Tainá (American). Lettuce seeds from each cultivar were superficially disinfected, pre-germinated for 24 hours and placed on the wat (more) er agar medium surface. Then, a dish containing mycelium from Pythium isolates was placed in the center of each plate. Control consisted of plates containing lettuce seeds only. Experimental design was completely randomized, with five replicates, each one represented by a Petri dish. Hypocotyl and radical length besides surviving seedlings percentage after ten days of incubation were evaluated. The experiment was carried out, at different temperatures, and the pathogenicity of the isolates was investigated at the ideal temperature for the lettuce (20ºC), and at the ideal temperatures for the growth of the isolates, 23ºC for P. middletonii and 27ºC for P. dissotocum. At 20ºC, P. dissotocum had higher pathogenicity on lettuce cultivars than P. middletonii, significantly decreasing the length of hypocotyls, especially radicles, of most cultivars. For P. dissotocum, 27ºC was the most suitable temperature for the specimen growth; however, it led to the lowest percentage of surviving seedlings among all cultivars, with the lowest percentage (54%) detected for Vera. Among the cultivars, Mimosa presented higher percentage of survivor seedlings and higher length of radicles in relation to the control, and thus was considered less susceptible to the pathogen. P. dissotocum presented higher mycelium growth and was more pathogenic than P. middletonii in all experiments.

Baptista, F.R.; Pires-Zottarelli, C.L.A; Teixeira, L.D.; Santos Júnior, N.A.

2011-03-01

55

Efficacy of bio-K fertilizer on the growth and sugar content of sugarcane plants  

International Nuclear Information System (INIS)

Bio-K- fertilizer has been used as a source of potassium to enhance the concentration of sugar in sugarcane and prevent loss of resources and environmental damage. Potassium sul phate and murate of Potash are K fertilizers. The field experiments were done during 2009-2010 to see the increase of sugar contents in sugarcane by using K- fertilizer. The use of bio-K-fertilizer has been found effective which resulted better yield in terms of both quantity and quality of sugarcane and found an increase in concentration of sucrose in sugarcane up to 28% calculated as 3-7% sugar content increase as a whole. The increase in crop production as whole was recorded as 74% due to Bio-K-fertilizer as compared to control plots. No chemical fertilizer was used during this experiment. (author)

56

Pythium Root Rot (and Feeder Root Necrosis)  

Science.gov (United States)

Pythium species cause a number of diseases on corn. Among the Pythium diseases, root rot presents the least conspicuous aboveground symptoms. Broadly defined, root rot also includes feeder root necrosis. At least 16 species of Pythium are known to cause root rot of corn. These include P. acanthicu...

57

Growth and Xylose consumption of Candida guilliermondii in the submerse fermentation using sugarcane bagasse  

Directory of Open Access Journals (Sweden)

Full Text Available The xylitol has been seen as a product with a great commercial value for the food and pharmaceutical industries as well the odontological sector for its notable characteristics like its sweet taste and prevention of caries, while is recommended to the obese and is tolerated by the diabetics. The xylitol may be obtained through chemical and biotechnological reactions. According to the literature the chemical production of xylitol involves an expensive and unproductive process in response to its purification. On the other hand the biotechnological has become an excellent alternative for its production, using submerse fermentative processes made by microorganisms. In the present research was studied the use of the biotechnological reaction, using the yeast Candida guilliermondii and sugarcane bagasse, a low cost agroindustrial residue used for xilose fermentation, as the substrate. Tests were made in duplicate and it was verified the fermentative capacity of three lineages of the C. guilliermondii at the times of 0, 24, 48, 72 and 96 hours. For the conversion of the xylana into xylose it was made an acid hydrolysis. Then it was used activated coal for the purification of the hydrolysate and supplementation of the fermentation medium with ammonium sulphate and rice bran. The fermentative process occurred in the shaker at 150rpm at 30ºC. This study intends to estimate through the yeast growth and the xylose consumption the best fermentative parameters to xylitol production. Among the lineages used the best one results were obtained by the LBP018, where it was obtained the highest biomass and faster xylose consumption..

Mário César Jucoski Bier et al.; Leila Teresinha Maranho; Jayme Augusto Menegassi Azevedo; Luiz Severo Da Silva Junior

2007-01-01

58

Carbon Isotope Discrimination, Gas Exchange, and Growth of Sugarcane Cultivars under Salinity.  

UK PubMed Central (United Kingdom)

Physiological features associated with differential resistance to salinity were evaluated in two sugarcane (Saccharum spp. hybrid) cultivars over an 8-week period during which greenhouse-grown plants were drip-irrigated with water or with NaCI solutions of 2, 4, 8, or 12 decisiemens (dS) m-1 electrical conductivity (EC). The CO2 assimilation rate (A), stomatal conductance (g), and shoot growth rate (SGR) began to decline as EC of the irrigation solution increased above 2 dS m-1. A, g, and SGR of a salinity-resistant cultivar (H69-8235) were consistently higher than those of a salinity-susceptible cultivar (H65-7052) at all levels of salinity and declined less sharply with increasing salinity. Carbon isotope discrimination ([delta]) in tissue obtained from the uppermost fully expanded leaf increased with salinity and with time elapsed from the beginning of the experiment, but [delta] was consistently lower in the resistant than in the susceptible cultivar at all levels of salinity. Gas-exchange measurements suggested that variation in [delta] was attributable largely to variation in bundle sheath leakiness to CO2 ([phi]). Salinity-induced increases in [phi] appeared to be caused by a reduction in C3 pathway activity relative to C4 pathway activity rather than by physical changes in the permeability of the bundle sheath to CO2. A strong correlation between [delta] and A, g, and SGR permitted these to be predicted from [delta] regardless of the cultivar and salinity level. [delta] thus provided an integrated measure of several components of physiological performance and response.

Meinzer FC; Plaut Z; Saliendra NZ

1994-02-01

59

Carbon Isotope Discrimination, Gas Exchange, and Growth of Sugarcane Cultivars under Salinity.  

Science.gov (United States)

Physiological features associated with differential resistance to salinity were evaluated in two sugarcane (Saccharum spp. hybrid) cultivars over an 8-week period during which greenhouse-grown plants were drip-irrigated with water or with NaCI solutions of 2, 4, 8, or 12 decisiemens (dS) m-1 electrical conductivity (EC). The CO2 assimilation rate (A), stomatal conductance (g), and shoot growth rate (SGR) began to decline as EC of the irrigation solution increased above 2 dS m-1. A, g, and SGR of a salinity-resistant cultivar (H69-8235) were consistently higher than those of a salinity-susceptible cultivar (H65-7052) at all levels of salinity and declined less sharply with increasing salinity. Carbon isotope discrimination ([delta]) in tissue obtained from the uppermost fully expanded leaf increased with salinity and with time elapsed from the beginning of the experiment, but [delta] was consistently lower in the resistant than in the susceptible cultivar at all levels of salinity. Gas-exchange measurements suggested that variation in [delta] was attributable largely to variation in bundle sheath leakiness to CO2 ([phi]). Salinity-induced increases in [phi] appeared to be caused by a reduction in C3 pathway activity relative to C4 pathway activity rather than by physical changes in the permeability of the bundle sheath to CO2. A strong correlation between [delta] and A, g, and SGR permitted these to be predicted from [delta] regardless of the cultivar and salinity level. [delta] thus provided an integrated measure of several components of physiological performance and response. PMID:12232101

Meinzer, F. C.; Plaut, Z.; Saliendra, N. Z.

1994-02-01

60

Virulence of Pythium species isolated from wheat fields in eastern Washington  

UK PubMed Central (United Kingdom)

Although Pythium root rot in wheat (Triticum aestivum) is well documented, limited information is available concerning which species of Pythium are most responsible for disease damage. The objective of this study was to examine the variation in virulence on wheat among isolates of Pythium collected from cereal grain fields in eastern Washington. Isolates of nine Pythium species were tested for virulence on spring wheat cultivars Chinese Spring and Spillman. Cultivars were planted in pasteurized soil infested with Pythium isolates and placed in a growth chamber maintained at a constant 16 degrees C and ambient humidity. Plant height, length of the first true leaf, and number of seminal roots were recorded, and roots were digitally scanned to create computer files that were analyzed using WinRhizo software. Pythium isolates caused a significant reduction (P < 0.05) in the number of root tips, root length, and length of the first leaf. Differences in virulence were detected among species and among isolates within species. Isolate Pythium debaryanum 90136 and P. ultimum 90038 were the most virulent and may prove useful in future disease screening assays of Triticum germ plasm.

Higginbotham RW; Paulitz TC; Kidwell KK

2004-09-01

 
 
 
 
61

Effect of iron, manganese, zinc and their combinations on growth and yield of sugarcane at Kenana sugar scheme  

International Nuclear Information System (INIS)

Two field experiments were conducted at two different sites for one season (1992/93) in order to study the effects of iron, manganese, zinc and their combinations on growth and yield of sugarcane at kenana sugar scheme. The experimental design used was a randomized complete block with four replications. Sulfates of iron, manganese and zinc were used as foliar fertilizers at concentrations of 200 ppm for iron and zinc and 100 ppm for manganese. Half of the fertilizer dose was applied when the crop was four months old, and the other half was applied when the crop was six months old, and the control was sprayed with distilled water only. All the treatments received 415 kg/ha urea fertilizer (46% nitrogen) as nitrogen source and 108 kg/ha triple superphosphate(48% P2 O5) as a source of phosphorus. Data were recorded on the growth and yield of sugarcane crop. The results showed that the lowest stalk height was obtained with treatments receiving iron fertilizer. The highest stalk diameter value was obtained in plants sprayed with zinc. The application of manganese or zinc and their combinations resulted in higher values of cane yield than the control. (Author)

2003-01-01

62

Etiology and epidemiology of Pythium root rot in hydroponic crops: current knowledge and perspectives  

Directory of Open Access Journals (Sweden)

Full Text Available The etiology and epidemiology of Pythium root rot in hydroponically-grown crops are reviewed with emphasis on knowledge and concepts considered important for managing the disease in commercial greenhouses. Pythium root rot continually threatens the productivity of numerous kinds of crops in hydroponic systems around the world including cucumber, tomato, sweet pepper, spinach, lettuce, nasturtium, arugula, rose, and chrysanthemum. Principal causal agents include Pythium aphanidermatum, Pythium dissotocum, members of Pythium group F, and Pythium ultimum var. ultimum. Perspectives are given of sources of initial inoculum of Pythium spp. in hydroponic systems, of infection and colonization of roots by the pathogens, symptom development and inoculum production in host roots, and inoculum dispersal in nutrient solutions. Recent findings that a specific elicitor produced by P. aphanidermatum may trigger necrosis (browning) of the roots and the transition from biotrophic to necrotrophic infection are considered. Effects on root rot epidemics of host factors (disease susceptibility, phenological growth stage, root exudates and phenolic substances), the root environment (rooting media, concentrations of dissolved oxygen and phenolic substances in the nutrient solution, microbial communities and temperature) and human interferences (cropping practices and control measures) are reviewed. Recent findings on predisposition of roots to Pythium attack by environmental stress factors are highlighted. The commonly minor impact on epidemics of measures to disinfest nutrient solution as it recirculates outside the crop is contrasted with the impact of treatments that suppress Pythium in the roots and root zone of the crop. New discoveries that infection of roots by P. aphanidermatum markedly slows the increase in leaf area and whole-plant carbon gain without significant effect on the efficiency of photosynthesis per unit area of leaf are noted. The platform of knowledge and understanding of the etiology and epidemiology of root rot, and its effects on the physiology of the whole plant, are discussed in relation to new research directions and development of better practices to manage the disease in hydroponic crops. Focus is on methods and technologies for tracking Pythium and root rot, and on developing, integrating, and optimizing treatments to suppress the pathogen in the root zone and progress of root rot.A etiologia e a epidemiologia da podridão radicular causada por Pythium spp. em cultivo hidropônico são revisadas com ênfase em conhecimentos e conceitos considerados importantes para o manejo de doenças em estufas comerciais. A podridão radicular causada por Pythium continuamente ameaça a produtividade de diversas culturas em sistemas hidropônicos, incluindo pepino, tomate, pimentão, espinafre, alface, capuchinha, rúcula, rosa, e crisântemo. Os principais agentes causais incluem Pythium aphanidermatum, Pythium dissotocum, espécies de Pythium do grupo F e Pythium ultimum var. ultimum. São apresentadas e discutidas as principais fontes do inóculo primário de Pythium spp. em sistemas hidropônicos, os processos de infecção e colonização de raízes pelos patógenos, o desenvolvimento de sintomas, a produção de inóculo em raízes, e a dispersão do inóculo na solução nutritiva. Descobertas recentes da existência de um elicitor produzido especificamente por P. aphanidermatum que pode provocar a necrose (descoloração) das raízes infectadas e a transição da infecção da fase biotrofica para necrotrofica são consideradas. Efeitos de fatores ligados ao hospedeiro (susceptibilidade à doença, estádio fenológico, exsudatos radiculares, compostos fenólicos), ao ambiente radicular (meio de enraizamento, concentrações de oxigênio dissolvido e compostos fenólicos na solução nutritiva, comunidades microbianas e temperatura) e as interferências humanas (práticas de cultivo e medidas de controle) sobre as epidemias de podridão radicular causados por Pythium spp. são revistos. Resultados r

John Clifford Sutton; Coralie Rachelle Sopher; Tony Nathaniel Owen-Going; Weizhong Liu; Bernard Grodzinski; John Christopher Hall; Ruth Linda Benchimol

2006-01-01

63

Etiology and epidemiology of Pythium root rot in hydroponic crops: current knowledge and perspectives  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese A etiologia e a epidemiologia da podridão radicular causada por Pythium spp. em cultivo hidropônico são revisadas com ênfase em conhecimentos e conceitos considerados importantes para o manejo de doenças em estufas comerciais. A podridão radicular causada por Pythium continuamente ameaça a produtividade de diversas culturas em sistemas hidropônicos, incluindo pepino, tomate, pimentão, espinafre, alface, capuchinha, rúcula, rosa, e crisântemo. Os principais agen (more) tes causais incluem Pythium aphanidermatum, Pythium dissotocum, espécies de Pythium do grupo F e Pythium ultimum var. ultimum. São apresentadas e discutidas as principais fontes do inóculo primário de Pythium spp. em sistemas hidropônicos, os processos de infecção e colonização de raízes pelos patógenos, o desenvolvimento de sintomas, a produção de inóculo em raízes, e a dispersão do inóculo na solução nutritiva. Descobertas recentes da existência de um elicitor produzido especificamente por P. aphanidermatum que pode provocar a necrose (descoloração) das raízes infectadas e a transição da infecção da fase biotrofica para necrotrofica são consideradas. Efeitos de fatores ligados ao hospedeiro (susceptibilidade à doença, estádio fenológico, exsudatos radiculares, compostos fenólicos), ao ambiente radicular (meio de enraizamento, concentrações de oxigênio dissolvido e compostos fenólicos na solução nutritiva, comunidades microbianas e temperatura) e as interferências humanas (práticas de cultivo e medidas de controle) sobre as epidemias de podridão radicular causados por Pythium spp. são revistos. Resultados recentes que demostram um aumento da predisposição das raízes ao ataque de Pythium induzida por estresses ambientais são destacados. O impacto das medidas usadas para a desinfestação da solução nutritiva recirculando fora do cultivo sobre a epidemia da doença é comparada com o impacto de tratamentos que suprimem Pythium nas raízes e na zona radicular da cultura. Novas descobertas de que a infeção de raízes por P. aphanidermatum reduz o crescimento da área foliar e o acúmulo de carbono na planta inteira, sem alterar significativamente a eficiência da fotossíntese por unidade de área foliar, são destacadas. O conhecimento e entendimento da etiologia e epidemiologia da podridão radicular, e seus efeitos na fisiologia da planta, são dicutidos em relacão às novas perspectivas das pesquisas e ao desenvolvimento de melhores práticas para o manejo da doença em cultivo hidropônico. Ênfase é dada nos métodos e tecnologias para a detecção de Pythium tanto na solução nutritiva quanto nas raízes e no desenvolvimento, integração e otimização dos tratamentos para suprimir o patógeno na zona radicular e o progresso da podridão das raízes. Abstract in english The etiology and epidemiology of Pythium root rot in hydroponically-grown crops are reviewed with emphasis on knowledge and concepts considered important for managing the disease in commercial greenhouses. Pythium root rot continually threatens the productivity of numerous kinds of crops in hydroponic systems around the world including cucumber, tomato, sweet pepper, spinach, lettuce, nasturtium, arugula, rose, and chrysanthemum. Principal causal agents include Pythium ap (more) hanidermatum, Pythium dissotocum, members of Pythium group F, and Pythium ultimum var. ultimum. Perspectives are given of sources of initial inoculum of Pythium spp. in hydroponic systems, of infection and colonization of roots by the pathogens, symptom development and inoculum production in host roots, and inoculum dispersal in nutrient solutions. Recent findings that a specific elicitor produced by P. aphanidermatum may trigger necrosis (browning) of the roots and the transition from biotrophic to necrotrophic infection are considered. Effects on root rot epidemics of host factors (disease susceptibility, phenological growth stage, root exudates and phenolic substances), the root environment (rooting med

Sutton, John Clifford; Sopher, Coralie Rachelle; Owen-Going, Tony Nathaniel; Liu, Weizhong; Grodzinski, Bernard; Hall, John Christopher; Benchimol, Ruth Linda

2006-09-01

64

EFFECT OF DIFFERENT SOURCES AND RATES OF NITROGEN AND SUPRA OPTIMAL LEVEL OF POTASSIUM FERTILIZATION ON GROWTH, YIELD AND NUTRIENT UPTAKE BY SUGARCANE GROWN UNDER SALINE CONDITIONS  

Directory of Open Access Journals (Sweden)

Full Text Available The results of our pervious studies indicated that application of potassium @150 kg K2O ha-1 is effective in achieving economical sugarcane yield and optimum nutrient uptake under saline conditions. Keeping in view these findings, experiments were conducted on salt-affected soils at three sites of Punjab, Pakistan to select a suitable source and rate of N for obtaining optimum sugarcane yield and nutrient uptake from salt-affected soils. The experiments were conducted with two sugarcane varieties, salt tolerant (SPSG-26) and sensitive (CP-77400) using supra optimal level of K (150 kg K2O ha-1) as sulphate of potash SOP, P @ 100 kg P2O5 ha-1 as DAP (diammonium phosphate) and N @100 and 200 kg N ha-1 as urea or calcium ammonium nitrate (CAN). The results showed that cane length and diameter, number of tillers per plant, cane yield and sugar recovery increased with the application of N in both the sugarcane varieties under normal or saline conditions. Sugarcane growth and yield increased with increasing N rate from 100 to 200 kg N ha-1 in case of both urea and CAN. However, CAN as N source was more effective in enhancing sugarcane growth and yield than urea. The concentration of Na+ increased in both the sugarcane varieties due to salinity, however, application of K and N decreased its concentration. The combined application of NPK also significantly reduced Na+ uptake in leaves, however, the best combination observed was DAP+SOP+CAN. It was also observed that salt tolerant variety (SPSG-26) had lesser accumulation of Na+ than that of sensitive one (CP-77400). Application of N fertilizers significantly enhanced the nutrient (K, P, and N) uptake in both the varieties at both N rates (100 and 200 kg N ha-1) under normal as well as saline conditions. However, maximum uptake of nutrients was recorded at the highest dose (200 kg N ha-1) but CAN treated plants performed better than that of urea. On the basis of above results, the application of K as SOP and N as CAN was recommended for salt-affected soils to enhance the sugarcane yield. The salt tolerant variety for higher yield in salt-affected soil is also necessary for improving the cost benefit ratio. The results revealed that if salinity level of soil would exceed 10 dS m-1, considerable reduction in sugarcane yield could occur.

M. YASIN ASHRAF; FAQIR HUSSAIN; JAVED1 AKHTAR; ATTIYA GUL; MARCUSS ROSS; GEORG EBERT

2008-01-01

65

Pythium oligandrum: an example of opportunistic success.  

UK PubMed Central (United Kingdom)

Pythium oligandrum, a non-pathogenic soil-inhabiting oomycete, colonizes the root ecosystem of many crop species. Whereas most members in the genus Pythium are plant pathogens, P. oligandrum distinguishes itself from the pathogenic species by its ability to protect plants from biotic stresses in addition to promoting plant growth. The success of P. oligandrum at controlling soilborne pathogens is partly associated with direct antagonism mediated by mycoparasitism and antimicrobial compounds. Interestingly, P. oligandrum has evolved with specific mechanisms to attack its prey even when these belong to closely related species. Of particular relevance is the question of how P. oligandrum distinguishes between self- and non-self cell wall degradation during the mycoparasitic process of pathogenic oomycete species. The ability of P. oligandrum to enter and colonize the root system before rapidly degenerating is one of the most striking features that differentiate it from all other known biocontrol fungal agents. In spite of this atypical behaviour, P. oligandrum sensitizes the plant to defend itself through the production of at least two types of microbe-associated molecular patterns, including oligandrin and cell wall protein fractions, which appear to be closely involved in the early events preceding activation of the jasmonic acid- and ethylene-dependent signalling pathways and subsequent localized and systemic induced resistance. The aim of this review is to highlight the expanding knowledge of the mechanisms by which P. oligandrum provides beneficial effects to plants and to explore the potential use of this oomycete or its metabolites as new disease management strategies.

Benhamou N; le Floch G; Vallance J; Gerbore J; Grizard D; Rey P

2012-11-01

66

Evaluation of Salt Tolerance of Sugarcane (Saccharum officinarum L.) Genotypes Based on the Ability to Regulate Ion Uptake and Transport at Early Stage of Growth  

Directory of Open Access Journals (Sweden)

Full Text Available   Sugarcane is one of the most important sugar crops in the world. Because of semi-arid climate and salinity of its cultivation area in our country, increasing salt tolerance of sugarcane is signifying. To achieve this goal determining salt tolerant cultivars and understanding salinity mechanisms in sugarcane are very important. This study was conducted to evaluate 8 commercial and promising sugarcane cultivars at early stage of growth. A complete randomized design with three replicates and four salinity treatments (0, 0.25, 0.5, 0.75 % NaCl) was used in a hydroponics system. The effect of salinity on absorption, transport and accumulation of Na+, Cl- , K+ and Ca2+ ions in shoot and root was determined. At high level salt concentration, Cl- content in shoot and root increased. Result showed that sodium accumulation in sugarcane plants was more than potassium. By increasing salinity level, sodium uptake and its translocation to shoots increased reducing growth and dry matter yield of plants. With rising salt concentration from medium (0.5%) to high (0.75%), content of chloride in shoot and root of NCO-310 was constant showed that this cultivar had genetic ability to avoid Cl- uptake. CP82-1592 with lowest ratio of shoot / root chloride had minimum transport of Cl- to shoots. Also this cultivar had high content of Ca2+ in shoot and low Na+/Ca2+ ratio at all salinity levels. CP48-103 had low sodium in shoot and relatively low sodium in root. Thus it probably has genetic potential to avoid sodium uptake. At last, exclusion of Na+ and Cl- to older leaves and tillers was seen in CP82-1592 and CP72-2086 cultivars. According to results, to avoid once of absorption and transport, and exclusion of harmful Na+ and Cl- ions were mechanisms that could be used in salinity tolerance of sugarcane.

M. Soltani Huwyzeh; S.A.M. Mirmohammady Maibody; A. Arzani

2008-01-01

67

The distribution and growth of roots for four sugarcane cultivars irrigated by a subsurface drip irrigation system  

Science.gov (United States)

The use of subsurface drip irrigation (SDI) in sugarcane cultivation is an interesting cultural practice to improve production and allow cultivation in marginal lands due to water deficit conditions or to reach high yield and to increase longevity of plants. The SDI allows improving the water use efficiency, due to the application of water and nutrients in the root zone plants. It is necessary knowledge of soil and plant parameters, such as root system to improve irrigation system use efficiency. However, despite of the agronomic importance, few studies of sugarcane roots have been performed. The use of root scanner is an alternative to the evaluation of the root system. The mentioned equipment enables the continuous study of the roots throughout the cycle and for many years, but data about the use of this method for sugarcane are scarce. The aim of this study was to determine the distribution and growth of roots for four sugarcane cultivars root system. The field experiment was carried out in Campinas SP Brazil, with IACSP95-5000, IACSP94-2094, IACSP94-2101 and SP79-1011 cultivars. The irrigation was performed by subsurface drip system and the soil moisture was monitored by capacitance probes. Three access tubes with 1.05 m-length were used for each cultivar. The images were caught with Root Scanner CI-600™ in two dates, 38 and 58 days after harvest (DAH) of cane-plant, in the second cycle (1st cane ratoon) in five depths and were analyzed by the software RootSnap! ™. The results show that, except for cultivar IACSP94-2094, more than 80% of root length was found in the first 0.40 m of soil profile. Until 38 DAH the root growth of cultivar IACSP94-2101 were approximately fourfold higher than other three ones in the 0 to 0.20 m layer, sevenfold higher to 0.20 to 0.40 m layer and threefold to 0.40 to 0.60 m soil profile layer. However, between 38 and 58 DAH the cultivar SP79-1011 presented higher growth taxes, being almost twofold higher than IACSP94-2101 at 0 to 0.20 m soil profile layer, although its growth rate for the other soil profile layers were between 38 and 57% of IACSP94-2101 rate. Compared to IACSP94-2101 and SP79-1011, the other two cultivars presented fivefold and sixfold lower growth rates in root length between 38 and 58 DAH in the first two layers, respectively. The higher root length in minirhizotron surface was with 0.64 cm cm-2, found in the 20-40 cm layer of IACSP94-2101, while the overall average was 0.15 cm cm-2. The percentage of root length in deeper layers increased between the first and second analyses.

Yukitaka Pessinatti Ohashi, Augusto; Barros de Oliveira Silva, André Luiz; Célia de Matos Pires, Regina; Vasconcelos Ribeiro, Rafael

2013-04-01

68

Two new species of Pythium, P. schmitthenneri and P. selbyi pathogens of corn and soybean in Ohio.  

Science.gov (United States)

Two new species of Pythium, pathogens of corn and soybean in Ohio, are described. Pythium schmitthenneri sp. nov. and Pythium selbyi sp. nov. both have morphological and sequence characteristics that place them in clade E1 of the genus Pythium. Morphology and sequence analysis of the ITS1-5.8S-ITS2 regions of these species were different from previously described species. The ITS region of Pythium schmitthenneri was 99.9% similar to P. acrogynum and 99.8% similar to P. hypogynum. All three species are characterized by globose to limoniform sporangia and plerotic oospores. Pythium schmitthenneri has mostly diclinous antheridia, compared to the strictly hypogynous antheridia of P. acrogynum and P. hypogynum. The temperature for growth of P. schmitthenneri is below 4 C to 32 C, and optimum growth is 18-25 C compared to 31-34 C for P. hypogynum. The ITS region of P. selbyi was 97.1% similar to P. longandrum and 97.5% similar to P. longisporangium. All three species are characterized by globose sporangia, mostly plerotic oospores, with one to two oospores per oogonium, and hypogynous or monoclinous antheridia. The temperature for growth of P. selbyi is below 4 to 32 C, with an optimum 18-25 C. These new species were widely dispersed throughout the soybean- and corn-producing regions in Ohio, making their characterization critical for managing the Pythium complex that causes seedling and root-rot disease in Ohio soybean and corn fields. PMID:22123655

Ellis, Margaret L; Paul, Pierce A; Dorrance, Anne E; Broders, Kirk D

2011-11-28

69

Two new species of Pythium, P. schmitthenneri and P. selbyi pathogens of corn and soybean in Ohio.  

UK PubMed Central (United Kingdom)

Two new species of Pythium, pathogens of corn and soybean in Ohio, are described. Pythium schmitthenneri sp. nov. and Pythium selbyi sp. nov. both have morphological and sequence characteristics that place them in clade E1 of the genus Pythium. Morphology and sequence analysis of the ITS1-5.8S-ITS2 regions of these species were different from previously described species. The ITS region of Pythium schmitthenneri was 99.9% similar to P. acrogynum and 99.8% similar to P. hypogynum. All three species are characterized by globose to limoniform sporangia and plerotic oospores. Pythium schmitthenneri has mostly diclinous antheridia, compared to the strictly hypogynous antheridia of P. acrogynum and P. hypogynum. The temperature for growth of P. schmitthenneri is below 4 C to 32 C, and optimum growth is 18-25 C compared to 31-34 C for P. hypogynum. The ITS region of P. selbyi was 97.1% similar to P. longandrum and 97.5% similar to P. longisporangium. All three species are characterized by globose sporangia, mostly plerotic oospores, with one to two oospores per oogonium, and hypogynous or monoclinous antheridia. The temperature for growth of P. selbyi is below 4 to 32 C, with an optimum 18-25 C. These new species were widely dispersed throughout the soybean- and corn-producing regions in Ohio, making their characterization critical for managing the Pythium complex that causes seedling and root-rot disease in Ohio soybean and corn fields.

Ellis ML; Paul PA; Dorrance AE; Broders KD

2012-03-01

70

Growth of the whole root system for a plant crop of sugarcane under rainfed and irrigated environments in Brazil  

UK PubMed Central (United Kingdom)

Sugarcane crops are managed over 8million hectares in Brazil and future extensions might occur on less favorable lands where irrigation would be necessary to increase and stabilize yields. Root growth was studied by sequential soil coring under rainfed and irrigated conditions for one cultivar widely planted in Brazil. Root length densities (RLD) were measured 34, 49, 125, 179, 241 and 322 days after planting (DAP) down to a depth of 1m. At the harvest (332DAP), root intersects (a proxy for RLD) were counted on two vertical trench walls in each water supply regime, down to a depth of 6.0m. The highest RLD in deep layers (below a depth of 0.6m) were observed in the rainfed crop from 125DAP onwards. By contrast, the highest RLD in the upper layers during dry periods were found in the irrigated crop. The maximum depth reached by roots at the harvest was little affected by irrigation: 4.70m and 4.25m in the rainfed and irrigated crop, respectively. About 50% of root intersects were observed below the depth of 1m in the two water supply regimes. This pattern suggested a strong genetic control of root growth in deep soil layers. The total amount of root intersects 332DAP was 49% higher in the rainfed crop than in the irrigated crop, and root distribution was more homogeneous. Mean root front velocity was about 0.5cmday?¹ the first 4 months after planting and increased thereafter up to the end of the harvest (1.86cmday?¹ and 1.75cmday?¹ on average in the rainfed and the irrigated crops, respectively). Our study pointed out the necessity to take into account the development of sugarcane roots in deep soil layers to improve our understanding of net primary production control by water availability.

Battie Laclau Patricia; Laclau Jean-Paul

2009-12-01

71

Growth of Chlorella vulgaris on Sugarcane Vinasse: The Effect of Anaerobic Digestion Pretreatment.  

UK PubMed Central (United Kingdom)

Microalgae farming has been identified as the most eco-sustainable solution for producing biodiesel. However, the operation of full-scale plants is still limited by costs and the utilization of industrial and/or domestic wastes can significantly improve economic profits. Several waste effluents are valuable sources of nutrients for the cultivation of microalgae. Ethanol production from sugarcane, for instance, generates significant amounts of organically rich effluent, the vinasse. After anaerobic digestion treatment, nutrient remaining in such an effluent can be used to grow microalgae. This research aimed to testing the potential of the anaerobic treated vinasse as an alternative source of nutrients for culturing microalgae with the goal of supplying the biodiesel industrial chain with algal biomass and oil. The anaerobic process treating vinasse reached a steady state at about 17 batch cycles of 24 h producing about 0.116 m(3)CH4 kgCODvinasse (-1). The highest productivity of Chlorella vulgaris biomass (70 mg l(-1) day(-1)) was observed when using medium prepared with the anaerobic digester effluent. Lipid productivity varied from 0.5 to 17 mg l(-1) day(-1). Thus, the results show that it is possible to integrate the culturing of microalgae with the sugarcane industry by means of anaerobic digestion of the vinasse. There is also the advantageous possibility of using by-products of the anaerobic digestion such as methane and CO2 for sustaining the system with energy and carbon source, respectively.

Marques SS; Nascimento IA; de Almeida PF; Chinalia FA

2013-09-01

72

Effect of Gamma Irradiation on Vegetative and Root Growth of three Sugarcane Genotypes (Smoocher officinarum L.) In vitro  

International Nuclear Information System (INIS)

Sugarcane explants of three genotypes namely CO.J.64, CO.J.86 and Missan were exposed to 0,10, 20, 30,40,Gray of gamma rays,and cultured in MS medium supplemented with hormones for vegetative and root growth. The cultures were including in growth room at 25±2 degree centigrade and 16th photo period with light intensity of 1000 Lux. Results of vegetative explants of three genotypes namely Co. J.64, Co.J.86 and Missan growth revealed gradual reductions in the number of shoots, fresh, and dry weights as with the increased of gamma doses, The reduction percentage were 59.40, 59.70 and 54.40% at 40 Gray respectively, as compared with control treatment, while the dose 10 Gray increased the shoot length by 10.90%.Mean time, gamma rays were significantly affected the root formation,no roots were developed when plants treated with 40 Gray,while 10 Gray reduced the number of root formation, lengths, fresh and dry weights of roots by 28.80, 12.30, 78.30 and 58. 60% respectively as compared with the control. However the genotype Co.J.86 was significantly superior than others in numbers and lengths of the shoots with the root lengths while higher fresh and dry weights of vegetative growth were obtained in Missan genotypes. (author)

2005-01-01

73

Pythium oligandrum: an example of opportunistic success.  

Science.gov (United States)

Pythium oligandrum, a non-pathogenic soil-inhabiting oomycete, colonizes the root ecosystem of many crop species. Whereas most members in the genus Pythium are plant pathogens, P. oligandrum distinguishes itself from the pathogenic species by its ability to protect plants from biotic stresses in addition to promoting plant growth. The success of P. oligandrum at controlling soilborne pathogens is partly associated with direct antagonism mediated by mycoparasitism and antimicrobial compounds. Interestingly, P. oligandrum has evolved with specific mechanisms to attack its prey even when these belong to closely related species. Of particular relevance is the question of how P. oligandrum distinguishes between self- and non-self cell wall degradation during the mycoparasitic process of pathogenic oomycete species. The ability of P. oligandrum to enter and colonize the root system before rapidly degenerating is one of the most striking features that differentiate it from all other known biocontrol fungal agents. In spite of this atypical behaviour, P. oligandrum sensitizes the plant to defend itself through the production of at least two types of microbe-associated molecular patterns, including oligandrin and cell wall protein fractions, which appear to be closely involved in the early events preceding activation of the jasmonic acid- and ethylene-dependent signalling pathways and subsequent localized and systemic induced resistance. The aim of this review is to highlight the expanding knowledge of the mechanisms by which P. oligandrum provides beneficial effects to plants and to explore the potential use of this oomycete or its metabolites as new disease management strategies. PMID:22977087

Benhamou, Nicole; le Floch, Gaêtan; Vallance, Jessica; Gerbore, Jonathan; Grizard, Damien; Rey, Patrice

2012-09-13

74

Comparison of two media selective for Phytophthora and Pythium species.  

UK PubMed Central (United Kingdom)

The standard selective medium for isolating pythiaceous fungi, P10VP (cornmeal agar amended with 10 mg/ L pimaricin, 200 mg/L vancomycin, and 100 mg/L PCNB), was compared with a modified version of this medium, P5ARP (pimaricin reduced to 5 mg/L and vancomycin replaced by 250 mg/L ampicillin + 10 mg/L rifampicin). Hymexazol (50 mg/L) was added (i.e., P10VPH and P5ARPH) to suppress unwanted Pythium colonies for direct enumeration of Phytophthora from soil. P5ARP(H), when compared with P10VP(H), 1) detected more germinable propagules of P. cinnamomi, P. parasitica var. nicotianae, and Pythium ultimum from naturally infested soils, 2) suppressed contaminating bacteria much better in the test soil, 3) was equally effective in isolating P. megasperma and P. cactorum from apple twigs, 4) was much less expensive to prepare, and 5) supported mycelium growth of 42 isolates of Phytophthora (13 species) and 10 isolates of Pythium (six species) equally well. PCNB was beneficial for reducing or eliminating background mycoflora on soil dilution plates. Hymexazol added to P5ARP greatly inhibited P. cactorum and drastically limited the radial growth of one isolate each of P. megasperma f. sp. medicaginis, P. megasperma f. sp. glycinea, and P. capsici. P5ARP(H) is an improvement over P10VP(H) as a multipurpose selective medium for isolating Phytophthora and Pythium species from plant tissue and soil.

Jeffers SN; Martin SB

1986-11-01

75

Modifications of PARP Medium Using Fluazinam, Miconazole, and Nystatin for Detection of Pythium spp. in Soil  

UK PubMed Central (United Kingdom)

The standard Pythium selective medium PARP (pimaricin + ampicillin + rifampicin + pentachloronitrobenzene [PCNB] agar), was modified by replacing PCNB and pimaricin with other antifungal agents. Several antifungal agents such as fluazinam, miconazole, 2,4,5,6-tetrachloroisophthalonitrile (TPN), iminoctadine triacetate, tolclofos-methyl, captan, and nystatin, initially were screened for effects on Pythium growth. Based on these results, the following three media were developed: PARF (pimaricin + ampicillin + rifampicin + fluazinam agar), NARF (nystatin + ampicillin + rifampicin + fluazinam agar), and NARM (nystatin + ampicillin + rifampicin + miconazole agar). New media were comparable with PARP on yield of naturally occurring Pythium spp. from two different types of soil using the soil-dilution plating technique. PARF and NARF were significantly better than PARP on inhibition of non-pythiaceous microbes on the soil-dilution plates, but were significantly lower than PARP on the rate of mycelial growth of six of eight isolates belonging to seven species of Pythium. NARM was equivalent to PARP on inhibition of non-pythiaceous microbes except for Fusarium oxysporum, and was significantly better than PARP on rate of mycelial growth of five of eight isolates of Pythium.

Morita Y; Tojo M

2007-12-01

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Effects of piperidine and piperideine alkaloids from the venom of red imported fire ants, Solenopsis invicta Buren, on Pythium ultimum Trow growth in vitro and the application of piperideine alkaloids to control cucumber damping-off in the greenhouse.  

UK PubMed Central (United Kingdom)

BACKGROUND: Pythium ultimum is a plant pathogen that causes significant yield losses on many economically important crops. Chemical treatment has been used for disease control. In searching for alternatives, venom piperidine and piperideine alkaloids from red imported fire ants were tested against P. ultimum in vitro, and piperideines were employed to control cucumber damping-off in the greenhouse as drench treatments. Results Piperidine and piperideine alkaloids of the red imported fire ant significantly inhibited mycelium growth of P. ultimum. Piperidine alkaloids were stable at both room and elevated temperatures. The inhibitory activity positively correlated with the concentrations of piperidine alkaloids in the medium, and the EC(50) = 17.0 µg ml(-1). Germination of sporangia of P. ultimum was negatively correlated with the concentrations of piperidine alkaloids in the medium, and the EC(50) = 12.3 µg ml(-1). The piperideine alkaloid drenching treatment significantly improved seedling emergence and seedling height of cucumber. CONCLUSION: This is the first report describing the use of venom alkaloids from the red imported fire ant to inhibit P. ultimum in the laboratory and the application of piperideine alkaloids to control damping-off disease caused by P. ultimum in the greenhouse. These findings may lead to the development of a new group of fungicides.

Li S; Jin X; Chen J

2012-12-01

77

Patogenicidade in vitro de Pythium aphanidermatum e Pythium dissotocum em variedades de alface (Lactuca sativa L.)/ Pathogenicity in vitro of Pythium aphanidermatum and Pythium dissotocum in varieties of lettuce (Lactuca sativa L.)  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese Pythium spp. são importantes causadoras de infecções radiculares nos cultivos hidropônicos, tendo sido objetivo deste estudo avaliar a patogenicidade de Pythium aphanidermatum e P. dissotocum, em alface. Placas de Petri contendo ágar-água e micélio dos isolados foram incubadas de 15 a 45 ºC, para verificação da temperatura ótima de crescimento, estabelecendo-se 31 ºC para P. aphanidermatum e, 26 ºC para P. dissotocum. Avaliou-se, então, a patogenicidade dos (more) espécimes nas suas temperaturas ótimas e, em 20 ºC, ideal para a alface, colocando-se sementes em ágar-água e um disco com micélio no centro das placas. Placas contendo somente sementes em meio de cultura serviram como controle. Verificou-se o comprimento dos hipocótilos, das radículas e a porcentagem de plântulas sobreviventes, selecionando-se P. aphanidermatum como mais patogênico; as variedades Vera e Tainá como menos suscetíveis e, Elisa, como mais suscetível. Abstract in english Pythium species are responsible for root rot in hydroponically grown, being the aims of this study to evaluate the Pythium aphanidermatum and P. dissotocum pathogenicity, in lettuce. Petri dishes contained water-agar and the mycelium of the isolates were incubated at 15 to 45 ºC to verify the optimum temperature of growth, which were 31 ºC for P. aphanidermatum and 26 ºC for P. dissotocum. It was evaluated the pathogenicity of the isolates in the optimum temperatures, (more) and 20 ºC ideal to lettuce, placing the seeds in water-agar and the mycelium in the center of the dishes. Petri dishes contained only the seeds in media as controls. It was evaluated the hypocotyl and primary root length and the percentage of survivors seedlings, selecting P. aphanidermatum as more pathogenic; Vera and Tainá varieties as less susceptible and Elisa most susceptible.

Patekoski, Katya da Silva; Zottarelli, Carmen Lidia Amorim Pires

2009-03-01

78

Evaluation of adapted wheat cultivars for tolerance to Pythium root rot  

UK PubMed Central (United Kingdom)

Genetic resistance in wheat (Triticum aestivum) against Pythium species would be an efficient means of control of this major root fungal pathogen, but so far no source has been identified. In addition, no long-term, sustainable options for controlling Pythium root rot are available; therefore, identifying and then incorporating genetic resistance into wheat cultivars would create an ideal method of control for this disease. The objective of this study was to examine the level of tolerance to Pythium root rot among a diverse set of wheat germ plasm collected from all major wheat production regions in the United States. Pythium debaryanum isolate 90136 and P. ultimum isolate 90038, previously identified as the most virulent Pythium isolates on wheat, were used to infest pasteurized soil, which was seeded with wheat genotypes and placed in a growth chamber maintained at a constant 16 degrees C with a 12-h photoperiod and ambient humidity. Length of the first leaf and plant height measurements were recorded, and roots were digitally scanned to create computer files that were analyzed using WinRhizo software for length and number of tips. Significant (P < 0.05) differences in plant variables were detected among wheat genotypes in the presence of both Pythium species, and a significant (P < 0.0001) correlation between plant stunting and root loss was detected. Based on both shoot and root measurements, Caledonia, Chinese Spring, MN97695, and OR942504 appear to be highly susceptible to Pythium root rot, whereas genotypes KS93U161, OH708, and Sunco were the most tolerant to this disease.

Higginbotham RW; Paulitz TC; Campbell KG; Kidwell KK

2004-09-01

79

Antigenic relationship between the animal and human pathogen Pythium insidiosum and nonpathogenic Pythium species.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Identification of the newly named pathogenic oomycete Pythium insidiosum and its differentiation from other Pythium species by morphologic criteria alone can be difficult and time-consuming. Antigenic analysis by fluorescent-antibody and immunodiffusion precipitin techniques demonstrated that the P....

Mendoza, L; Kaufman, L; Standard, P

80

Pathogenicity of Pythium species on cucumber in peat-sand rockwool and hydroponics.  

UK PubMed Central (United Kingdom)

Pythium spp. that cause damping-off of seedlings also can cause root rot of older plants and lead to yield reductions. This can be especially severe in soilless cultures where the fungus can spread easily with the nutrient solution. 39Pythium isolates obtained from discolored roots were assayed for their ability to cause damping-off on cucumber seedlings in sand-peat and for their pathogenicity in soilless culture of cucumber in rockwool or hydroponic solution. Isolates ofPythium aphanidermatum, P. irregulare, P. sylvaticum andP. ultimum were highly pathogenic in sand-peat, but onlyP. aphanidermatum strains were pathogenic in soilless conditions and led to root decay, plant death in rockwool culture and growth reduction in hydroponic culture. One strain ofP. aphanidermatum significantly reduced the yield of cucumber grown in rockwool under conditions similar to those of commercial cultures.

Moulin F; Lemanceau P; Alabouvette C

1994-04-01

 
 
 
 
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Clauraila E from the roots of Clausena harmandiana and antifungal activity against Pythium insidiosum.  

UK PubMed Central (United Kingdom)

A new carbazole alkaloid named clauraila E (1) together with 8 known compounds were isolated from the methanol extract of the roots of Clausena harmandiana. All compounds were evaluated for antifungal activity against Pythium insidiosum using disc diffusion assay. Pythium insidiosum is a fungus-like microorganism, for which antifungals available now are not effective. It was found that compounds 3, 6, 7 and 9 could inhibit the mycelia growth of P. insidiosum. The results show convincingly that they may be lead to compounds for the development of probiotic or novel antifungal drugs.

Sriphana U; Thongsri Y; Prariyachatigul C; Pakawatchai C; Yenjai C

2013-09-01

82

Clauraila E from the roots of Clausena harmandiana and antifungal activity against Pythium insidiosum.  

UK PubMed Central (United Kingdom)

A new carbazole alkaloid named clauraila E (1) together with 8 known compounds were isolated from the methanol extract of the roots of Clausena harmandiana. All compounds were evaluated for antifungal activity against Pythium insidiosum using disc diffusion assay. Pythium insidiosum is a fungus-like microorganism, for which antifungals available now are not effective. It was found that compounds 3, 6, 7 and 9 could inhibit the mycelia growth of P. insidiosum. The results show convincingly that they may be lead to compounds for the development of probiotic or novel antifungal drugs.

Sriphana U; Thongsri Y; Prariyachatigul C; Pakawatchai C; Yenjai C

2013-04-01

83

Clauraila E from the roots of Clausena harmandiana and antifungal activity against Pythium insidiosum.  

Science.gov (United States)

A new carbazole alkaloid named clauraila E (1) together with 8 known compounds were isolated from the methanol extract of the roots of Clausena harmandiana. All compounds were evaluated for antifungal activity against Pythium insidiosum using disc diffusion assay. Pythium insidiosum is a fungus-like microorganism, for which antifungals available now are not effective. It was found that compounds 3, 6, 7 and 9 could inhibit the mycelia growth of P. insidiosum. The results show convincingly that they may be lead to compounds for the development of probiotic or novel antifungal drugs. PMID:23595552

Sriphana, Uraiwan; Thongsri, Yordhathai; Prariyachatigul, Chularut; Pakawatchai, Chaveng; Yenjai, Chavi

2013-04-18

84

Soil physical properties and sugarcane root growth in a red oxiso Propriedades físicas de solo e crescimento radicular de cana-de-açúcar em um latossolo vermelho  

Directory of Open Access Journals (Sweden)

Full Text Available Sugarcane, which involves the use of agricultural machinery in all crop stages, from soil preparation to harvest, is currently one of the most relevant crops for agribusiness in Brazil. The purpose of this study was to investigate soil physical properties and root growth in a eutroferric red Oxisol (Latossolo Vermelho eutroférrico) after different periods under sugarcane. The study was carried out in a cane plantation in Rolândia, Paraná State, where treatments consisted of a number of cuts (1, 3, 8, 10 and 16), harvested as green and burned sugarcane, at which soil bulk density, macro and microporosity, penetration resistance, as well as root length, density and area were determined. Results showed that sugarcane management practices lead to alterations in soil penetration resistance, bulk density and porosity, compared to native forest soil. These alterations in soil physical characteristics impede the full growth of the sugarcane root system beneath 10 cm, in all growing seasons analyzed.A cana-de-açúcar é, na atualidade, uma das culturas de maior importância no agronegócio brasileiro, a qual envolve o uso de máquinas agrícolas em todas as fases do cultivo - do preparo do solo até a colheita. O objetivo deste trabalho foi estudar os atributos físicos e o crescimento de raízes em Latossolo Vermelho eutroférrico cultivado com cana-de-açúcar por diferentes períodos de tempo. O estudo foi conduzido em uma área de produção de cana-de-açúcar em Rolândia, Paraná, com diferentes tratamentos (número de cortes: 1, 3, 8, 10 e 16); a colheita foi realizada com cana queimada e corte manual, determinando-se: densidade, macro e microporosidade, resistência do solo à penetração, densidade do solo, densidade de comprimento e área de raízes. Conclui-se que as práticas de manejo na cultura da cana-de-açúcar promovem alterações na resistência, densidade e porosidade do solo, em comparação com a mata nativa; essas alterações nos atributos físicos foram impeditivas ao pleno desenvolvimento radicular da cana-de-açúcar além de 10 cm de profundidade, em todos os períodos de cultivo analisados.

José Euripides Baquero; Ricardo Ralisch; Cristiane de Conti Medina; João Tavares Filho; Maria de Fátima Guimarães

2012-01-01

85

Effects of purified piperidine and piperideine alkaloids from the venom of red imported fire ant, Solenopsis invicta on Pythium ultimum growth in vitro and on cucumber damping-off in the greenhouse  

Science.gov (United States)

Pythium ultimum Trow is a plant pathogen that causes significant yield losses on many economically important crops. Chemical seed treatment has been used for disease control. In searching for alternatives, the venom alkaloids from red imported fire ant were tested against P. ultimum in vitro and to ...

86

A simple, rapid and inexpensive screening method for the identification of Pythium insidiosum.  

UK PubMed Central (United Kingdom)

Growth of Pythium insidiosum mycelia around minocycline disks (30?g) did not occur within 7days of incubation at 35°C when the isolates were grown on Sabouraud, corn meal, Muller-Hinton or RPMI agar. This technique offers a simple and rapid method for the differentiation of P. insidiosum from true filamentous fungi.

Tondolo JS; Loreto ES; Denardi LB; Mario DA; Alves SH; Santurio JM

2013-04-01

87

A simple, rapid and inexpensive screening method for the identification of Pythium insidiosum.  

Science.gov (United States)

Growth of Pythium insidiosum mycelia around minocycline disks (30?g) did not occur within 7days of incubation at 35°C when the isolates were grown on Sabouraud, corn meal, Muller-Hinton or RPMI agar. This technique offers a simple and rapid method for the differentiation of P. insidiosum from true filamentous fungi. PMID:23419825

Tondolo, Juliana Simoni Moraes; Loreto, Erico Silva; Denardi, Laura Bedin; Mario, Débora Alves Nunes; Alves, Sydney Hartz; Santurio, Janio Morais

2013-02-16

88

Um simulador dinâmico do crescimento de uma cultura de cana-de-açúcar/ A dynamic simulator of the sugarcane crop growth  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese Este trabalho descreve a primeira versão de um simulador matemático-fisiológico do crescimento diário de uma cultura de cana-de-açúcar (SIMCANA) em resposta às condições do ambiente durante a estação de crescimento. SIMCANA resume a maior parte das informações disponíveis concernentes aos processos fisiológicos da cultura de cana-de-açúcar. Esta sua versão não incluí os processos degerminação e florescimento, havendo necessidade de especificar as con (more) dições da cultura no primeiro dia de simulação. Em função das condições diárias de radiação solar global, temperatura máxima e mínima, umidade relativa do ar, SIMCANA calcula as taxas de fotossíntese, respiração e crescimento da cultura, as taxas de senescência das folhas e raízes, a massa seca das folhas, colmos e raízes, e o índice de área foliar. Embora várias relações empíricas tenham sido usadas, SIMCANA parece ser capaz de simular o crescimento da cultura de cana-de-açúcar. Abstract in english The first version of a mathematical-physiological simulator of the daily growth of a sugarcane crop (SIMCANA) as a function of the environmental conditions during the growing season is described. SIMCANA summarizes most of the available information regarding to the physiological processes of the sugarcane crop. This version does not include the germination and flowering processes, therefore it is necessary to specify the crop conditions at the first day of simulation. Giv (more) en the daily conditions of global solar radiation, maximum and minimum temperature, and the relative humidity, SIMCANA computes the rates of crop photosynthesis, respiration, and growth, the senescence rates for leaves and roots, the dry mass of leaves, stems, and roots, and the leaf area index. Although several empirical relations have been used, SIMCANA seems to be able to simulate the sugarcane crop growth.

Pereira, Antonio Roberto; Machado, Eduardo Caruso

1986-01-01

89

Effect of salinity on pythium damping-off of cucumber and on the tolerance of Pythium aphanidermatum  

UK PubMed Central (United Kingdom)

A study was conducted to investigate the effect of salinity on pythium damping-off and tolerance to salinity among Pythium aphanidermatum isolates from different geographical origins, genetic backgrounds and saline/non-saline soils. Increasing irrigation-water salinity from 0·01 to 5 dS m?¹ significantly increased mortality in cucumber seedlings inoculated with P. aphanidermatum and reduced dry weight of non-inoculated seedlings. In vitro tests in culture media amended with different concentrations of NaCl showed that growth of P. aphanidermatum, P. spinosum and P. splendens isolates was stimulated or unaffected at salinity levels stressful for cucumber (electrical conductivity = 5 dS m?¹). Significant differences were found in tolerance to salinity among 47 P. aphanidermatum isolates obtained from different greenhouses. The concentration of NaCl required to reduce growth of P. aphanidermatum isolates by 50% varied from 23 to 62 dS m?¹, with an average of 46 dS m?¹, however, oospore production was more sensitive to salinity and no oospores were produced above 20 dS m?¹. Analysis of tolerance of P. aphanidermatum isolates to salinity showed no relationship between tolerance to salinity and geographical origins or genetic data. Isolates of P. aphanidermatum from greenhouses with no salinity problems were as tolerant to salinity as isolates obtained from salinity-affected greenhouses, suggesting lack of evidence for ecological adaptation within P. aphanidermatum in Oman. Increased mortality in cucumber seedlings at higher salinity levels may imply a synergistic interaction between salinity stress and salinity-tolerant Pythium species on cucumber seedlings, resulting in greater seedling losses.

Al-Sadi AM; Al-Masoudi RS; Al-Habsi N; Al-Said FA; Al-Rawahy SA; Ahmed M; Deadman ML

2010-02-01

90

Rhizosphere Competence of Pythium oligandrum.  

UK PubMed Central (United Kingdom)

ABSTRACT The associations of Pythium oligandrum with the root cortex, rhizoplane, and rhizosphere were measured with 11 crop species. This work was expedited by the use of a semiselective technique for isolation of P. oligandrum from soil and plant material. Cortical colonization of roots by P. oligandrum was not detected, and the rhizoplanes of the roots of most crops were free of the fungus. However, P. oligandrum was detected in large quantities with every crop tested when roots with adhering soil (rhizosphere soil) were assayed. Different crop species and cultivars of cantaloupe, cauliflower, and tomato varied in rhizosphere densities of P. oligandrum, but rhizosphere population densities of the fungus were consistently higher than in nonrhizosphere soils with plants grown in P. oligandrum-infested sterilized potting mix or an unsterilized mineral soil. After transplanting tomatoes into potting mix infested with P. oligandrum, increases in CFU occurred over time in the rhizosphere but not in the nonrhizosphere soil. In trials on delivery methods of inoculum of P. oligandrum, the rhizosphere populations of tomato plants grown in potting mix were about sixfold higher compared to seed-coat treatments when ground, alginate pelleted oospores were applied to seedlings growing in plug containers prior to transplanting or to pots containing potting mix before direct seeding.

Al-Rawahi AK; Hancock JG

1997-09-01

91

Morphological and molecular taxonomy of Pythium longisporangium sp. nov. isolated from the Burgundian region of France.  

UK PubMed Central (United Kingdom)

During the course of an investigation on the Pythiaceous oomycetes occurring in the Burgundian vineyards, some species of Pythium possessing mainly hypogynous antheridia were found. These had been classified as oomycetes belonging to the "Pythium rostratum" group for a long time. Three of these isolates, having similar structures and growth, are very closely related to a recently described species, Pythium bifurcatum Paul. A close look at these, however, underlines some fundamental differences with the latter. Not all of them produce zoospores but have very large sporangia. The type specimen is F-1200 (B 76a) which is a medium-slow growing saprophyte. The sequence of the ITS region of the rDNA also shows a very close relationship with P. bifurcatum. On the basis of morphological and molecular analysis, we now describe this species as Pythium longisporangium sp. nov. Morphological features of this new species, the sequences of the ITS region of its nuclear ribosomal DNA, and its comparison with related species are discussed.

Paul B; Bala K; Gognies S; Belarbi A

2005-05-01

92

Thioquinolobactin, a Pseudomonas siderophore with antifungal and anti-Pythium activity.  

Science.gov (United States)

Under conditions of iron limitation Pseudomonas fluorescens ATCC 17400 produces two siderophores, pyoverdine, and a second siderophore quinolobactin, which itself results from the hydrolysis of the unstable molecule 8-hydroxy-4-methoxy-2-quinoline thiocarboxylic acid (thioquinolobactin). Pseudomonas fluorescens ATCC 17400 also displays a strong in vitro antagonism against the Oomycete Pythium, which is repressed by iron, suggesting the involvement of a siderophore(s). While a pyoverdine-negative mutant retains most of its antagonism, a thioquinolobactin-negative mutant only slowed-down Pythium growth, and a double pyoverdine-, thioquinolobactin-negative mutant, which does not produce any siderophore, totally lost its antagonism against Pythium. The siderophore thioquinolobactin could be purified and identified from spent medium and showed anti-Pythium activity, but it was quickly hydrolysed to quinolobactin, which we showed has no antimicrobial activity. Analysis of antagonism-affected transposon mutants revealed that genes involved in haem biosynthesis and sulfur assimilation are important for the production of thioquinolobactin and the expression of antagonism. PMID:17222140

Matthijs, Sandra; Tehrani, Kourosch Abbaspour; Laus, George; Jackson, Robert W; Cooper, Richard M; Cornelis, Pierre

2007-02-01

93

OREGON BLUEBERRY SURVEY: PHYTOPHTHORA AND PYTHIUM  

Science.gov (United States)

In August of 2001, we sampled 55 fields in Oregon to assess the presence of Phytophthora and Pythium spp. in blueberry fields under production conditions and to determine whether any relationships exist between field characteristics, root distribution, and soil characteristics. Phytophthora spp, fr...

94

Sugarcane Harvest Aid  

UK PubMed Central (United Kingdom)

Protoporphyrinogen oxidase enzyme-inhibiting compounds are useful in compositions and methods for ripening sugarcane crops. Of particular interest is the use of carfentrazone ethyl and certain metabolites thereof for ripening sugarcane crops.

BORGES ALAN

95

SUGARCANE HARVEST AID  

UK PubMed Central (United Kingdom)

Protoporphyrinogen oxidase enzyme-inhibiting compounds are useful in compositions and methods for ripening sugarcane crops. Of particular interest is the use of carfentrazone ethyl and certain metabolites thereof for ripening sugarcane crops.

BORGES Alan

96

Solarização do solo e incorporação de fontes de matéria orgânica no controle de Pythium spp. Soil solarization in combination with organic matter for the control of Pythium spp.  

Directory of Open Access Journals (Sweden)

Full Text Available O objetivo deste trabalho foi avaliar o efeito da solarização do solo, associada à incorporação de lodo de esgoto, cama-de-frango e casca de Pinus, no controle de Pythium spp. Foram conduzidos dois ensaios, um em área cultivada comercialmente com crisântemo e outro em área artificialmente infestada com Pythium spp. em cultivo de pepino. A adição de cama-de-frango induziu a supressividade do solo ao patógeno, visto que resultou em maiores temperaturas no solo solarizado, aumento na condutividade elétrica e maior atividade microbiana do solo, avaliada pela hidrólise de diacetato de fluoresceína e desprendimento de CO2. Por outro lado, o lodo de esgoto e a casca de Pinus não induziram a supressividade ao patógeno. A solarização não teve efeito no crescimento da parte aérea e no peso de matéria fresca de raízes de plantas de crisântemo, mas teve efeito significativo no controle do patógeno no ensaio conduzido com pepino.The objective of this work was to evaluate the effect of soil solarization in combination with sewage sludge, chicken litter and Pinus bark added to soil for the control of Pythium spp. Two field experiments with chrysanthemum and cucumber were carried out in two soils: one commercially cultivated with chrysanthemum and in the other artificially infested with Pythium spp. The effects of the treatments were evaluated by measuring electrical conductivity, pH, microbial activity of soil as well as shoot growth and root fresh weight of chrysanthemum plant. The chicken litter induced suppressiveness to the pathogen due to higher soil temperatures, enhanced electrical conductivity, and increased microbial activity, which was evaluated by diacetate fluorescein hydrolysis and CO2 emission. On the other hand, the sewage sludge and the Pinus bark did not induce pathogen suppressiveness. Solarization did not affect plant shoot growth nor root fresh weight of chrysanthemum plants, but it significantly controlled the pathogen in the experiment with cucumber.

Raquel Ghini; Ivone Alberta Swart Schoenmaker; Wagner Bettiol

2002-01-01

97

Solarização do solo e incorporação de fontes de matéria orgânica no controle de Pythium spp./ Soil solarization in combination with organic matter for the control of Pythium spp.  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese O objetivo deste trabalho foi avaliar o efeito da solarização do solo, associada à incorporação de lodo de esgoto, cama-de-frango e casca de Pinus, no controle de Pythium spp. Foram conduzidos dois ensaios, um em área cultivada comercialmente com crisântemo e outro em área artificialmente infestada com Pythium spp. em cultivo de pepino. A adição de cama-de-frango induziu a supressividade do solo ao patógeno, visto que resultou em maiores temperaturas no solo so (more) larizado, aumento na condutividade elétrica e maior atividade microbiana do solo, avaliada pela hidrólise de diacetato de fluoresceína e desprendimento de CO2. Por outro lado, o lodo de esgoto e a casca de Pinus não induziram a supressividade ao patógeno. A solarização não teve efeito no crescimento da parte aérea e no peso de matéria fresca de raízes de plantas de crisântemo, mas teve efeito significativo no controle do patógeno no ensaio conduzido com pepino. Abstract in english The objective of this work was to evaluate the effect of soil solarization in combination with sewage sludge, chicken litter and Pinus bark added to soil for the control of Pythium spp. Two field experiments with chrysanthemum and cucumber were carried out in two soils: one commercially cultivated with chrysanthemum and in the other artificially infested with Pythium spp. The effects of the treatments were evaluated by measuring electrical conductivity, pH, microbial acti (more) vity of soil as well as shoot growth and root fresh weight of chrysanthemum plant. The chicken litter induced suppressiveness to the pathogen due to higher soil temperatures, enhanced electrical conductivity, and increased microbial activity, which was evaluated by diacetate fluorescein hydrolysis and CO2 emission. On the other hand, the sewage sludge and the Pinus bark did not induce pathogen suppressiveness. Solarization did not affect plant shoot growth nor root fresh weight of chrysanthemum plants, but it significantly controlled the pathogen in the experiment with cucumber.

Ghini, Raquel; Schoenmaker, Ivone Alberta Swart; Bettiol, Wagner

2002-09-01

98

Exploiting sugarcane for energy  

Science.gov (United States)

Energycane can be described as sugarcane varieties with fiber content that is higher than the level seen in sugarcane varieties used for commercial sugar production. This fiber content is composed of cellulose, hemicellulose, and lignin. Approximately 70 percent of the dry weight of sugarcane is cel...

99

Girassol: emergência e crescimento inicial de plantas sob resíduos de cana-de-açúcar Sunflower: emergence and initial plant growth under sugarcane residues  

Directory of Open Access Journals (Sweden)

Full Text Available O objetivo do trabalho foi avaliar o efeito da palha residual da colheita da cana-de-açúcar e da adição de vinhaça sobre o solo na emergência e no crescimento inicial de cultivares de girassol. Os tratamentos foram dispostos em esquema fatorial (5 x 2 x 3), em blocos ao acaso, com quatro repetições, combinando-se cinco quantidades de palha de cana-de-açúcar (0, 5, 10, 15 e 20t ha-1) com aplicação ou não de 150m³ ha-1 de vinhaça residual da indústria sulcroalcooleira, utilizando-se três cultivares de girassol ("IAC-iarama", "Catissol" e "Helio 358"). Foram determinadas a velocidade e a porcentagem final de emergência de plântulas, além do comprimento e da biomassa seca da parte aérea de plantas aos 30 dias após a semeadura. Verificou-se que a presença da palha de cana-de-açúcar e da vinhaça, em quantidade equivalente a 150m³ ha-1, em ação conjunta ou isolada, reduz a emergência de plântulas e o crescimento inicial de cultivares de girassol. Entretanto, essa redução não compromete drasticamente o desempenho das cultivares ("IAC-iarama", "Catissol" e "Helio-358"), que não diferiram entre si.The aim of this research was to evaluate the effect of the interaction of soil cover with sugarcane mulch residue combined with vinasse application on seedling emergence and initial growth of sunflower cultivars. A greenhouse experiment was carried out in pots with soil, in randomized complete blocks, with four replications. The treatments, arranged in a 5 x 2 x 3 factorial, consisted of the combination of five quantities of sugarcane mulch residue cover (0, 5, 10, 15 and 20t ha-1) followed by application or not of 150m³ ha-1 of vinasse, on soil planted to the sunflower cultivars 'IAC-iarama', 'Catissol' e 'Helio 358'. The variables studied were seedling emergence speed, final emergence, as well as plant height and dry weight of above ground plant biomass. It is concluded that, under greenhouse conditions, the presence of sugarcane mulch residue in any of the quantities studied, and of vinasse in the quantity of 150m³ ha-1, either isolated or in combination, reduce seedling emergence and hamper the initial growth of sunflower, but this effect is not so drastic to endanger the cultivars development ('IAC-iarama', 'Catissol' e 'Helio-358'), that do not differ between them.

Nilza Patrícia Ramos; Maria do Carmo de Salvo Soares Novo; Antônio Augusto Lago; Maria Regina Gonçalves Ungaro

2009-01-01

100

Girassol: emergência e crescimento inicial de plantas sob resíduos de cana-de-açúcar/ Sunflower: emergence and initial plant growth under sugarcane residues  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese O objetivo do trabalho foi avaliar o efeito da palha residual da colheita da cana-de-açúcar e da adição de vinhaça sobre o solo na emergência e no crescimento inicial de cultivares de girassol. Os tratamentos foram dispostos em esquema fatorial (5 x 2 x 3), em blocos ao acaso, com quatro repetições, combinando-se cinco quantidades de palha de cana-de-açúcar (0, 5, 10, 15 e 20t ha-1) com aplicação ou não de 150m³ ha-1 de vinhaça residual da indústria sulcro (more) alcooleira, utilizando-se três cultivares de girassol ("IAC-iarama", "Catissol" e "Helio 358"). Foram determinadas a velocidade e a porcentagem final de emergência de plântulas, além do comprimento e da biomassa seca da parte aérea de plantas aos 30 dias após a semeadura. Verificou-se que a presença da palha de cana-de-açúcar e da vinhaça, em quantidade equivalente a 150m³ ha-1, em ação conjunta ou isolada, reduz a emergência de plântulas e o crescimento inicial de cultivares de girassol. Entretanto, essa redução não compromete drasticamente o desempenho das cultivares ("IAC-iarama", "Catissol" e "Helio-358"), que não diferiram entre si. Abstract in english The aim of this research was to evaluate the effect of the interaction of soil cover with sugarcane mulch residue combined with vinasse application on seedling emergence and initial growth of sunflower cultivars. A greenhouse experiment was carried out in pots with soil, in randomized complete blocks, with four replications. The treatments, arranged in a 5 x 2 x 3 factorial, consisted of the combination of five quantities of sugarcane mulch residue cover (0, 5, 10, 15 and (more) 20t ha-1) followed by application or not of 150m³ ha-1 of vinasse, on soil planted to the sunflower cultivars 'IAC-iarama', 'Catissol' e 'Helio 358'. The variables studied were seedling emergence speed, final emergence, as well as plant height and dry weight of above ground plant biomass. It is concluded that, under greenhouse conditions, the presence of sugarcane mulch residue in any of the quantities studied, and of vinasse in the quantity of 150m³ ha-1, either isolated or in combination, reduce seedling emergence and hamper the initial growth of sunflower, but this effect is not so drastic to endanger the cultivars development ('IAC-iarama', 'Catissol' e 'Helio-358'), that do not differ between them.

Ramos, Nilza Patrícia; Novo, Maria do Carmo de Salvo Soares; Lago, Antônio Augusto; Ungaro, Maria Regina Gonçalves

2009-02-01

 
 
 
 
101

Determination of Optimum Level of Phosphorus and its Effect on Growth, Yield and Quality of Ratoon Sugarcane (Saccharum officinarum L.)  

Directory of Open Access Journals (Sweden)

Full Text Available The various components of the sugarcane crop such as stripped cane yield, number of millable canes and unstripped cane yield were affected significantly by different levels of phosphorus. Phosphorus application in the range of 100-150 kg ha-1 along with 200-kg ha-1 and 150 kg K2O ha-1 was found to be an optimum dose. Phosphorus application beyond the range of 100 to 150 kg ha-1 will not be profitable. Phosphorus had non-significant effect on the photo biomass and quality parameters.

Aman Ullah Chaudhry; F.A.Chattha

2000-01-01

102

Crescimento e fotossíntese de cana-de-açúcar em função de variáveis biométricas e meteorológicas Growth and photosynthesis of sugarcane based on biometric and meteorological variables  

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Full Text Available O crescimento da cana-de-açúcar pode ser obtido por modelos biofísicos em que a fotossíntese bruta (FB) é obtida em função da radiação solar. O objetivo do trabalho é avaliar variedades de canas-de-açúcar em regime irrigado em relação à radiação fotossinteticamente ativa interceptada (RFAINT) e a estimativa da FB acumulada. Para isto, conduziu-se um estudo na Universidade Federal de Alagoas, entre 2008 e 2009, com variedades de cana RB. Foram realizadas medidas biométricas, variáveis de produção e dos elementos meteorológicos. A irradiância fotossintética (RFA) interceptada foi obtida pela diferença entre RFA e RFA transmitida (RFAT). A RFAT foi determinada pela Lei de Beer. Na estimativa da FB diária usou-se uma integração numérica, com uma abordagem trapezoidal. As variáveis de produção tiveram correlações com a RFAINT acumulada e com a FB acumulada durante o ciclo. A média da irradiação solar global diária do período chuvoso da região (maio - agosto) foi igual a 14,9 MJ m-2. A variedade RB92579 teve os maiores variáveis de produção, como também maiores RFA interceptada e FB acumuladas no ciclo, devido à sua maior capacidade de rebrotação e conversão de energia em fotoassimilados.Sugarcane growth can be obtained by biophysical models in which gross photosynthesis (GP) is obtained as a function of solar radiation. This work aims to evaluate sugarcane varieties under irrigation in relation to intercepted photosynthetic active radiation (PARint) and the estimated accumulative GP. To achieve that, a study was conducted at the Federal University of Alagoas during 2008 and 2009, with RB sugarcane varieties. Biometric measurements, production variables and meteorological elements were made. The intercepted photosynthetic irradiance (PAR) was obtained by the difference between PAR and transmitted PAR (PART), which was determined by Beer's Law. The daily GP was estimated numerically by the trapezoidal approach. The production variables had correlations with accumulated PARint and accumulated GP during the crop cycle. The average global solar radiation in the region for rainy season (May-August) was 14.9 MJ m-2. The variety RB92579 had the highest production variables as well as higher intercepted PAR and accumulated GP in the cycle due to its greater capacity for regrowth and energy conversion in photoassimilate.

Ricardo A. Ferreira Junior; José L. de Souza; Gustavo B. Lyra; Iêdo Teodoro; Marcos A. dos Santos; Anthony C. S. Porfirio

2012-01-01

103

Crescimento e fotossíntese de cana-de-açúcar em função de variáveis biométricas e meteorológicas/ Growth and photosynthesis of sugarcane based on biometric and meteorological variables  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese O crescimento da cana-de-açúcar pode ser obtido por modelos biofísicos em que a fotossíntese bruta (FB) é obtida em função da radiação solar. O objetivo do trabalho é avaliar variedades de canas-de-açúcar em regime irrigado em relação à radiação fotossinteticamente ativa interceptada (RFAINT) e a estimativa da FB acumulada. Para isto, conduziu-se um estudo na Universidade Federal de Alagoas, entre 2008 e 2009, com variedades de cana RB. Foram realizadas m (more) edidas biométricas, variáveis de produção e dos elementos meteorológicos. A irradiância fotossintética (RFA) interceptada foi obtida pela diferença entre RFA e RFA transmitida (RFAT). A RFAT foi determinada pela Lei de Beer. Na estimativa da FB diária usou-se uma integração numérica, com uma abordagem trapezoidal. As variáveis de produção tiveram correlações com a RFAINT acumulada e com a FB acumulada durante o ciclo. A média da irradiação solar global diária do período chuvoso da região (maio - agosto) foi igual a 14,9 MJ m-2. A variedade RB92579 teve os maiores variáveis de produção, como também maiores RFA interceptada e FB acumuladas no ciclo, devido à sua maior capacidade de rebrotação e conversão de energia em fotoassimilados. Abstract in english Sugarcane growth can be obtained by biophysical models in which gross photosynthesis (GP) is obtained as a function of solar radiation. This work aims to evaluate sugarcane varieties under irrigation in relation to intercepted photosynthetic active radiation (PARint) and the estimated accumulative GP. To achieve that, a study was conducted at the Federal University of Alagoas during 2008 and 2009, with RB sugarcane varieties. Biometric measurements, production variables a (more) nd meteorological elements were made. The intercepted photosynthetic irradiance (PAR) was obtained by the difference between PAR and transmitted PAR (PART), which was determined by Beer's Law. The daily GP was estimated numerically by the trapezoidal approach. The production variables had correlations with accumulated PARint and accumulated GP during the crop cycle. The average global solar radiation in the region for rainy season (May-August) was 14.9 MJ m-2. The variety RB92579 had the highest production variables as well as higher intercepted PAR and accumulated GP in the cycle due to its greater capacity for regrowth and energy conversion in photoassimilate.

Ferreira Junior, Ricardo A.; Souza, José L. de; Lyra, Gustavo B.; Teodoro, Iêdo; Santos, Marcos A. dos; Porfirio, Anthony C. S.

2012-11-01

104

Effect of Soil Acidity on Diseases Caused by Pythium ultimum and Fusarium oxysporum on Tomato Plants  

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Full Text Available Pythium ultimum and Fusarium oxysporum are important pathogens in agriculture crops and cause serious diseases that resulted in reducing the yield of many crops. The effect of soil acidity on the occurrence and severity of diseases caused by Pythium ultimum and Fusarium oxysporum were examined. Pathogens were grew at pH levels of 2-10 in vitro. Pythium ultimum and Fusarium oxysporum isolates have an optimum growth pH level of 6 and 7 and grew well at pH level of 5 and slightly at pH level of 4 and 8 but no growth at pH levels of 2, 3, 9 and 10. Six treatments (4, 5, 6, 7, 8 and 9) were tested in vivo to examine the effect of soil pH on the occurrence and severity of disease. The pH level of 5 was the best for plant growth but not to both pathogens. However, more disease severity by the two pathogens were found at the pH levels of 6 and 7. The pH levels could be used to reduce the plant disease reduction by knowing the optimum levels for plants and pathogens.

Khalaf M. Alhussaen

2012-01-01

105

Oligonucleotide Array for Identification and Detection of Pythium Species†  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A DNA array containing 172 oligonucleotides complementary to specific diagnostic regions of internal transcribed spacers (ITS) of more than 100 species was developed for identification and detection of Pythium species. All of the species studied, with the exception of Pythium ostracodes, exhibited a...

Tambong, J. T.; de Cock, A. W. A. M.; Tinker, N. A.; Lévesque, C. A.

106

Dynamic distribution of potassium in sugarcane.  

UK PubMed Central (United Kingdom)

In this work the distribution of potassium in sugarcane has been studied during its growth. The soil was prepared with natural fertilizers prepared with sugarcane bagasse. For the measurement of potassium concentration in each part of the plant, gamma-ray spectrometry was used to measure gamma-rays emitted from the radioisotope (40)K. The concentrations of potassium in roots, stems and leaves were measured every two to three months beginning about five months after planting the sugarcane. The results show a higher concentration of potassium at the beginning of plant development and over time, there is an oscillatory behavior in this concentration in each part of the plant, reaching a lower concentration in the adult plant. To describe the evolution of potassium distribution in sugarcane we proposed a phenomenological model assuming that the potassium incorporation rate is proportional to the difference between the element concentration in the plant and a very long term equilibrium value and it is coupled to a resource-limited growth model. The proposed model succeeded in interpreting the results for the potassium distribution in stems and leaves during the sugarcane growth.

Medina NH; Branco ML; Silveira MA; Santos RB

2013-09-01

107

Increasing P-Availability and P-Uptake Using Sugarcane Filter Cake and Rice Husk Ash to Improve Chinesse Cabbage (Brassica Sp) Growth in Andisol, East Java  

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Full Text Available The production potential in Andisols is limited by the high P-retention capacity. Farmers commonly use organic matter. Sugarcane filter cake (blothong, Indonesian, SFC) and rice husk ash (RHA) are locally available in Coban Rondo, Malang, East Java and hence potentially used for soil amendment. To study the effects of SFC and RHA on P availability, P uptake and plant growth (Brassica sp.), soil samples were taken from 0-20 cm depth, incubated with SFC (21.37 Mg.ha-1) and RHA (44.64 Mg.ha-1). Total P, P-available, pH, organic carbon, exchangeable cations (K, Na, Ca, Mg), and P retention curve were determined at 0, 15, 30, and 45 days after incubation. Crop parameters (height, number of leaves, total dry weight) and P-uptake were also measured at 2, 4, 6 weeks after planting. The results showed that RHA was more effective than SFC to decrease P retention and increase P availability (120% on RHA; and 78% on SFC). Soils having higher organic matter tended to have higher P availability. As a consequence, RHA and SFC increased P-uptake respectively 3 and 2 times in soil rich in organic matter, and 1.9 and 2.7 times in soil low in organic matter compared to untreated soil. Increasing P-uptake was followed by plant growth improvement. RHA was more effective than SFC in soil rich in organic matter, but not soil low in organic matter.

S. R. Utami; S. Kurniawan; B. Situmorang; N. D. Rositasari

2012-01-01

108

Carbohydrate-active enzymes in pythium and their role in plant cell wall and storage polysaccharide degradation.  

Science.gov (United States)

Carbohydrate-active enzymes (CAZymes) are involved in the metabolism of glycoconjugates, oligosaccharides, and polysaccharides and, in the case of plant pathogens, in the degradation of the host cell wall and storage compounds. We performed an in silico analysis of CAZymes predicted from the genomes of seven Pythium species (Py. aphanidermatum, Py. arrhenomanes, Py. irregulare, Py. iwayamai, Py. ultimum var. ultimum, Py. ultimum var. sporangiiferum and Py. vexans) using the "CAZymes Analysis Toolkit" and "Database for Automated Carbohydrate-active Enzyme Annotation" and compared them to previously published oomycete genomes. Growth of Pythium spp. was assessed in a minimal medium containing selected carbon sources that are usually present in plants. The in silico analyses, coupled with our in vitro growth assays, suggest that most of the predicted CAZymes are involved in the metabolism of the oomycete cell wall with starch and sucrose serving as the main carbohydrate sources for growth of these plant pathogens. The genomes of Pythium spp. also encode pectinases and cellulases that facilitate degradation of the plant cell wall and are important in hyphal penetration; however, the species examined in this study lack the requisite genes for the complete saccharification of these carbohydrates for use as a carbon source. Genes encoding for xylan, xyloglucan, (galacto)(gluco)mannan and cutin degradation were absent or infrequent in Pythium spp.. Comparative analyses of predicted CAZymes in oomycetes indicated distinct evolutionary histories. Furthermore, CAZyme gene families among Pythium spp. were not uniformly distributed in the genomes, suggesting independent gene loss events, reflective of the polyphyletic relationships among some of the species. PMID:24069150

Zerillo, Marcelo M; Adhikari, Bishwo N; Hamilton, John P; Buell, C Robin; Lévesque, C André; Tisserat, Ned

2013-09-12

109

Carbohydrate-active enzymes in pythium and their role in plant cell wall and storage polysaccharide degradation.  

UK PubMed Central (United Kingdom)

Carbohydrate-active enzymes (CAZymes) are involved in the metabolism of glycoconjugates, oligosaccharides, and polysaccharides and, in the case of plant pathogens, in the degradation of the host cell wall and storage compounds. We performed an in silico analysis of CAZymes predicted from the genomes of seven Pythium species (Py. aphanidermatum, Py. arrhenomanes, Py. irregulare, Py. iwayamai, Py. ultimum var. ultimum, Py. ultimum var. sporangiiferum and Py. vexans) using the "CAZymes Analysis Toolkit" and "Database for Automated Carbohydrate-active Enzyme Annotation" and compared them to previously published oomycete genomes. Growth of Pythium spp. was assessed in a minimal medium containing selected carbon sources that are usually present in plants. The in silico analyses, coupled with our in vitro growth assays, suggest that most of the predicted CAZymes are involved in the metabolism of the oomycete cell wall with starch and sucrose serving as the main carbohydrate sources for growth of these plant pathogens. The genomes of Pythium spp. also encode pectinases and cellulases that facilitate degradation of the plant cell wall and are important in hyphal penetration; however, the species examined in this study lack the requisite genes for the complete saccharification of these carbohydrates for use as a carbon source. Genes encoding for xylan, xyloglucan, (galacto)(gluco)mannan and cutin degradation were absent or infrequent in Pythium spp.. Comparative analyses of predicted CAZymes in oomycetes indicated distinct evolutionary histories. Furthermore, CAZyme gene families among Pythium spp. were not uniformly distributed in the genomes, suggesting independent gene loss events, reflective of the polyphyletic relationships among some of the species.

Zerillo MM; Adhikari BN; Hamilton JP; Buell CR; Lévesque CA; Tisserat N

2013-01-01

110

Microbes - friends and foes of sugarcane.  

UK PubMed Central (United Kingdom)

Sugarcane is an important cash crop for many countries because it is a major source of several products including sugar and bioethanol. To obtain maximum yields there is a need to apply large quantities of chemical fertilizers.Worldwide yields are also severely affected by more than sixty diseases, mostly caused by fungi but viruses, phytoplasmas, nematodes and other pests can also damage this crop. For most of these diseases, chemical control is not available and breeders are struggling with the development of pest resistant varieties. Many members of the grass family Poaceae establish associations with beneficial microbes which promote their growth by direct and indirect mechanisms. They can be used as means to reduce the need for chemical fertilizer and to minimize the impacts of pathogen invasion. This review highlights the diversity of the microbes associated with sugarcane and the role of beneficial microbes for growth promotion and biocontrol. More extensive use of beneficial microbes will help the sugarcane grower not only to reduce the use of chemical fertilizers but also minimize the disease. In this paper, a brief description of both the non-pathogenic and pathogenic microbes associated with sugarcane is provided. Future prospects for the expanded use of beneficial microbes for sugarcane are also discussed and detailed herein.

Mehnaz S

2013-01-01

111

Sugarcane binding bed  

UK PubMed Central (United Kingdom)

The utility model provides a sugarcane binding bed, which is provided with a bed body. The bed body is composed of two side parts and a middle part. The two side parts are the same in structure and symmetrical, a U-shaped sugarcane holding fork is arranged on the upper portion of each side part and formed by welding iron tubes and a small channel bar, a 'hash sign' shaped fixing rack formed by welding iron tubes and a larger channel bar is arranged on the lower portion of each side part, the bottom of each sugarcane holding fork is inserted into the upper portion of the corresponding fixing rack through the channel bar, each sugarcane holding fork with one end fixed is capable of tilting optionally, a slide ring is sleeved on a middle connecting bar and connected with a binding assistant bar through a binding assistant rope. The sugarcane binding bed is effectively practical, and sugarcanes with sundries cut off can be placed on the sugarcane binding bed and bound well easily only under interaction between the binding assistant bar and the rope, so that time and labor are saved, and sugarcanes are bound firmly and neatly without excess leaves. The bed body is structurally solid and durable, flexible, light, and convenient to carry, and labor efficiency is improved greatly.

ANCHENG BI

112

Reguladores vegetais e qualidade tecnológica da cana-de-açúcar em meio de safra Growth regulators and technological quality of sugarcane in the middle of the cropping season  

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Full Text Available A maturação da cana-de-açúcar (Saccharum officinarum L.) refere-se a um dos aspectos fundamentais para o sistema de produção da indústria sucroalcooleira. Objetivou-se, neste trabalho, avaliar a qualidade tecnológica da cana-de-açúcar em função da aplicação de reguladores vegetais em meio de safra. O delineamento experimental utilizado foi o de blocos casualizados com cinco repetições, sendo os tratamentos constituídos da aplicação de quatro maturadores da classe dos retardantes de crescimento (Ethefon, Etil-trinexapac, KNO3 e KNO3 + Boro) e uma testemunha (maturação natural). A eficiência agronômica dos maturadores foi influenciada pela época de aplicação, pela condição climática e pela característica genética da variedade. A aplicação dos maturadores em 10/05/2004 permitiu explorar de forma significativa o potencial genético da variedade quanto ao acúmulo de sacarose nos colmos, implicando em melhoria na qualidade tecnológica da matéria-prima. A adoção dessa prática em 04/08/2005, de modo geral, pouco afetou os parâmetros tecnológicos, exceto a aplicação de Etil-trinexapac, o qual induziu melhoria significativa na qualidade da matéria-prima. A produtividade de açúcar refletiu-se de forma direta na margem de contribuição agrícola, sendo constatado maior retorno econômico para as plantas tratadas com KNO3 na safra 2004.The ripening of sugarcane (Saccharum officinarum L.) is the most important aspect in the production system for sugar and alcohol industry. The objective of this work was to evaluate the technological quality of sugarcane as a function of plant regulators application in the middle of the cropping season. The experiment was carried out in a randomized block design with five replications. The treatments consisted of four plant regulators application of the class of growth retainers (Ethephon, Ethyl.trinexapac, Potassium nitrate and Potassium nitrate + Boron) and a control (natural ripening). The agricultural efficiency of maturators was affected by time application, weather condition and genetic characteristic of variety. The maturation application on 10/05/2004 allowed to explore of a significant form the genetic potential of variety as to sucrose storage in stems implicating in improvement technological quality of raw material. The maturation application on 04/08/2005 little affected technological parameters, except for Ethyl-trinexapac application, that induced significant improvement in technological quality of raw material. The sugar productivity reflected direct agricultural contribution and provided greater economical return with Potassium nitrate treatment in 2004.

Glauber Henrique Pereira Leite; Carlos Alexandre Costa Crusciol; Marcelo de Almeida Silva; Waldemar Gastoni Venturini Filho

2008-01-01

113

Reguladores vegetais e qualidade tecnológica da cana-de-açúcar em meio de safra/ Growth regulators and technological quality of sugarcane in the middle of the cropping season  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese A maturação da cana-de-açúcar (Saccharum officinarum L.) refere-se a um dos aspectos fundamentais para o sistema de produção da indústria sucroalcooleira. Objetivou-se, neste trabalho, avaliar a qualidade tecnológica da cana-de-açúcar em função da aplicação de reguladores vegetais em meio de safra. O delineamento experimental utilizado foi o de blocos casualizados com cinco repetições, sendo os tratamentos constituídos da aplicação de quatro maturadores (more) da classe dos retardantes de crescimento (Ethefon, Etil-trinexapac, KNO3 e KNO3 + Boro) e uma testemunha (maturação natural). A eficiência agronômica dos maturadores foi influenciada pela época de aplicação, pela condição climática e pela característica genética da variedade. A aplicação dos maturadores em 10/05/2004 permitiu explorar de forma significativa o potencial genético da variedade quanto ao acúmulo de sacarose nos colmos, implicando em melhoria na qualidade tecnológica da matéria-prima. A adoção dessa prática em 04/08/2005, de modo geral, pouco afetou os parâmetros tecnológicos, exceto a aplicação de Etil-trinexapac, o qual induziu melhoria significativa na qualidade da matéria-prima. A produtividade de açúcar refletiu-se de forma direta na margem de contribuição agrícola, sendo constatado maior retorno econômico para as plantas tratadas com KNO3 na safra 2004. Abstract in english The ripening of sugarcane (Saccharum officinarum L.) is the most important aspect in the production system for sugar and alcohol industry. The objective of this work was to evaluate the technological quality of sugarcane as a function of plant regulators application in the middle of the cropping season. The experiment was carried out in a randomized block design with five replications. The treatments consisted of four plant regulators application of the class of growth re (more) tainers (Ethephon, Ethyl.trinexapac, Potassium nitrate and Potassium nitrate + Boron) and a control (natural ripening). The agricultural efficiency of maturators was affected by time application, weather condition and genetic characteristic of variety. The maturation application on 10/05/2004 allowed to explore of a significant form the genetic potential of variety as to sucrose storage in stems implicating in improvement technological quality of raw material. The maturation application on 04/08/2005 little affected technological parameters, except for Ethyl-trinexapac application, that induced significant improvement in technological quality of raw material. The sugar productivity reflected direct agricultural contribution and provided greater economical return with Potassium nitrate treatment in 2004.

Leite, Glauber Henrique Pereira; Crusciol, Carlos Alexandre Costa; Silva, Marcelo de Almeida; Venturini Filho, Waldemar Gastoni

2008-12-01

114

Chemo sterilization of the sugarcane borer Diatraea saccharalis (Fabricius, 1794) (Lepidoptera: Crambidae) with sugar solution bait and insecticides of insect growth regulators group  

International Nuclear Information System (INIS)

The sugarcane borer Diatraea saccharalis (Fabricius, 1794) (Lepidoptera: Crambidae) is an important pest in Brazilian sugarcane crops. Currently, biological control is the most frequently used method for controlling D saccharalis. However, in several locations, the parasitoid Cotesia flavipes (Cameron) (Hymenoptera: Braconidae) has not been effective for controlling this pest, and it has been recorded infestation intensity above 25%. In this context, the Sterile Insect Technique could be an additional control method in Integrated Pest Management, because it is compatible with other control methods. The use of insecticides that interferes in hormone homeostasis involved in the ecdyse's process with exogenous hormone sources or synthetic analogues (agonists or antagonists) can result in the interruption of the reproductive process or abnormal development of the insect?s embryo. Then, the objective of this study was to evaluate the insecticides that regulates the insect growth on the D. saccharalis reproduction. The insecticides tested were: chlorfluazuron (1,0 and 1,5 g a.i./L), diflubenzuron (3,75; 5,0 and 7,5 g a.i./L), flufenoxuron (1,0 g a.i./L), lufenuron (0,75; 1,0 and 2,0 g a.i./L), novaluron (0,5 and 1,0 g a.i./L) pyriproxyfen (1,0; 1,5; 1,8 and 2,0 g a.i./L) and teflubenzuron (1,5; 3,0 and 6,0 g a.i./L). Each insecticide was provided to 1-day moths on soaked cotton with a sugar solution at 10% as a bait. All treatments, except to of the lowest concentration of lufenuron (0,75 g a.i./L) decreased the egg production in relation to the control. Flufenoxuron (1,00 g g a.i./L) and chlorfluazuron (1,50 g a.i./L) decreased the lifespan of both sexes treated by ingestion. Lufenuron (2,0 g a.i./L), novaluron (1,0 g a.i./L) and teflubenzuron (3,0 g a.i./L) decreased the male's lifespan. The most effective treatments for sterilization were pyriproxyfen (1,8 g a.i./L and 2,0 g a.i./L) and lufenuron (2,0 g a.i./L), witch showed efficiencies greater or close to 80%. (author)

2006-01-01

115

Supplementation of sugarcane bagasse with rice bran and sugarcane molasses for shiitake (Lentinula edodes) spawn production  

Directory of Open Access Journals (Sweden)

Full Text Available The purpose of this study was to assess the myceliation rate, mycelial vigor and "estimated biomass" of Lentinula edodes (Berk.) Pegler, grown on a sugarcane bagasse substrate enriched with rice bran and sugarcane molasses for spawn production. The proportions of rice bran used were 0, 10, 15, 20, 25, 30 and 40% (dry weight/dry weight of bagasse) and the sugarcane molasses concentrations tested were 0, 10, 20, 30, 40, 50 and 60 g/kg (dry weight/dry weight of bagasse plus rice bran). The myceliation rate was decreased by the addition of the higher quantities of rice bran. The 25 and 30% rice bran proportions induced the highest stimulation of mycelial vigor. The addition of sugarcane molasses did not change myceliation rate or mycelial vigor. The "estimated biomass" values were similar when intermediate rice bran proportions were used and for all sugarcane molasses concentrations. Based on response surface obtained for the "estimated biomass" data, higher values were obtained with substrates containing 20 to 25% rice bran combined with 10 to 30 g sugarcane molasses, although the latter supplement was not considered to stimulate L. edodes growth.

Rossi Ivan Henrique; Monteiro Antonio Carlos; Machado José Octavio; Barbosa José Carlos

2003-01-01

116

Patogenicidade de Pythium aphanidermatum a alface cultivada em hidroponia e seu biocontrole com Trichoderma Pythium aphanidermatum pathogenicity to hydroponics lettuce and its biocontrol with Trichoderma  

Directory of Open Access Journals (Sweden)

Full Text Available O objetivo deste trabalho foi avaliar a patogenicidade de Pythium aphanidermatum a variedades de alface, e a ação do produto Biotrich, formulado com Trichoderma, no controle deste patógeno e na promoção do crescimento das plantas. Em experimento in vitro, plântulas recém-germinadas das variedades de alface Vera e Elisa foram colocadas em placas de Petri com ágar-água e 1 mL de suspensão do produto Biotrich (0,2 mL L-1) e, após 24 horas, em discos com micélio do isolado de Pythium. As avaliações foram realizadas após dez dias de incubação a 20 e 31ºC. Os testes in vivo foram realizados na primavera e verão, em sistema hidropônico "Nutrient Film Technique" (NFT), em delineamento inteiramente casualizado, em esquema fatorial 2x2x2, como segue: duas variedades; presença ou ausência do patógeno; e presença ou ausência de Biotrich. Ao final do cultivo, foram avaliadas as massas de matéria fresca e seca das plantas. No experimento in vitro, P. aphanidermatum apresentou maior agressividade a 31ºC. Contudo, não foi verificada patogenicidade nos testes in vivo. De modo geral, o Biotrich não promoveu o crescimento das plantas, mas foi efetivo no controle do patógeno in vitro. Pythium aphanidermatum é patogênico às variedades de alface Vera e Elisa, a 20 e 31ºC, e o Biotrich é efetivo para o controle desse patógeno nessas temperaturas.The objective of this work was to evaluate the pathogenicity of Pythium aphanidermatum to lettuce varieties, and the action of the product Biotrich, formulated with Trichoderma, in the control of this pathogen and its effect on plant growth promotion. In a in vitro experiment, germinated seedlings of Vera and Elisa lettuce varieties were placed in Petri dishes with water-agar and 1mL Biotrich suspension (0.2 mL L-1), and after 24 hours, on plugs with the Pythium isolate mycelium. The evaluations were done ten days after the incubation at 20 and 31ºC. In vivo experiments were carried out during the spring and summer, using the Nutrient Film Technique (NFT) system, in a completely randomized design, following a 2x2x2 factorial arrangement, as well: two varieties; pathogen abscence or presence; and with or without Biotrich addition. At the end of cultivation, the fresh and dry weight of shoots and roots were analyzed. In vitro, P. aphanidermatum had increased aggressiveness at 31ºC. However, no pathogenicity was observed in vivo. Generally, Biotrich did not promote plant growth; however, it was effective in controlling the pathogen in vitro. Pythium aphanidermatum is pathogenic to lettuce varieties Vera and Elisa, at 20 and 31ºC, and Biotrich is effective for its control at these temperatures.

Katya da Silva Patekoski; Carmen Lidia Amorim Pires-Zottarelli

2010-01-01

117

Patogenicidade de Pythium aphanidermatum a alface cultivada em hidroponia e seu biocontrole com Trichoderma/ Pythium aphanidermatum pathogenicity to hydroponics lettuce and its biocontrol with Trichoderma  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese O objetivo deste trabalho foi avaliar a patogenicidade de Pythium aphanidermatum a variedades de alface, e a ação do produto Biotrich, formulado com Trichoderma, no controle deste patógeno e na promoção do crescimento das plantas. Em experimento in vitro, plântulas recém-germinadas das variedades de alface Vera e Elisa foram colocadas em placas de Petri com ágar-água e 1 mL de suspensão do produto Biotrich (0,2 mL L-1) e, após 24 horas, em discos com micélio d (more) o isolado de Pythium. As avaliações foram realizadas após dez dias de incubação a 20 e 31ºC. Os testes in vivo foram realizados na primavera e verão, em sistema hidropônico "Nutrient Film Technique" (NFT), em delineamento inteiramente casualizado, em esquema fatorial 2x2x2, como segue: duas variedades; presença ou ausência do patógeno; e presença ou ausência de Biotrich. Ao final do cultivo, foram avaliadas as massas de matéria fresca e seca das plantas. No experimento in vitro, P. aphanidermatum apresentou maior agressividade a 31ºC. Contudo, não foi verificada patogenicidade nos testes in vivo. De modo geral, o Biotrich não promoveu o crescimento das plantas, mas foi efetivo no controle do patógeno in vitro. Pythium aphanidermatum é patogênico às variedades de alface Vera e Elisa, a 20 e 31ºC, e o Biotrich é efetivo para o controle desse patógeno nessas temperaturas. Abstract in english The objective of this work was to evaluate the pathogenicity of Pythium aphanidermatum to lettuce varieties, and the action of the product Biotrich, formulated with Trichoderma, in the control of this pathogen and its effect on plant growth promotion. In a in vitro experiment, germinated seedlings of Vera and Elisa lettuce varieties were placed in Petri dishes with water-agar and 1mL Biotrich suspension (0.2 mL L-1), and after 24 hours, on plugs with the Pythium isolate m (more) ycelium. The evaluations were done ten days after the incubation at 20 and 31ºC. In vivo experiments were carried out during the spring and summer, using the Nutrient Film Technique (NFT) system, in a completely randomized design, following a 2x2x2 factorial arrangement, as well: two varieties; pathogen abscence or presence; and with or without Biotrich addition. At the end of cultivation, the fresh and dry weight of shoots and roots were analyzed. In vitro, P. aphanidermatum had increased aggressiveness at 31ºC. However, no pathogenicity was observed in vivo. Generally, Biotrich did not promote plant growth; however, it was effective in controlling the pathogen in vitro. Pythium aphanidermatum is pathogenic to lettuce varieties Vera and Elisa, at 20 and 31ºC, and Biotrich is effective for its control at these temperatures.

Patekoski, Katya da Silva; Pires-Zottarelli, Carmen Lidia Amorim

2010-08-01

118

Outbreak of Pythium keratitis during rainy season: a case series.  

UK PubMed Central (United Kingdom)

PURPOSE: To describe typical clinical and laboratory characteristics of severe fungal keratitis caused by Pythium insidiosum during the rainy season in Northeast Thailand and to report the efficacy of P. insidiosum vaccine in the treatment of Pythium keratitis. METHODS: A series of hospital-based consecutive cases of Pythium keratitis were diagnosed and treated at Srinagarind Hospital (Khon Kaen University, Khon Kaen, Thailand). The clinical presentations, diagnostic tests, and management are described. RESULTS: Severe fungal keratitis caused by P. insidiosum was diagnosed in 5 eyes of 4 patients between May 2009 and July 2009. All cases had a history of fungal keratitis after being exposed to contaminated water. Upon slit-lamp examination, subepithelial and superficial stromal opacities were observed in a reticular pattern in all cases. Pythium insidiosum was identified and confirmed by both microbiological culture and polymerase chain reaction. Clinical worsening was detected after conventional treatment with antifungal agents. Therapeutic penetrating keratoplasty with either donor cornea or scleral graft was performed together with topical antifungal administration and P. insidiosum vaccination. Subsequent evisceration was performed in 1 eye. CONCLUSIONS: An outbreak of Pythium keratitis in Northeast Thailand was reported. Distinctive clinical features are a suggestive clue for early diagnosis. Combination treatment including topical antifungal agents, radical surgery, and P. insidiosum vaccine may be considered for the management of Pythium keratitis.

Thanathanee O; Enkvetchakul O; Rangsin R; Waraasawapati S; Samerpitak K; Suwan-apichon O

2013-02-01

119

Enzymatic variability among Brazilian Pythium insidiosum isolates.  

UK PubMed Central (United Kingdom)

BACKGROUND: Pythium insidiosum is an oomycete classified in the Kingdom Stramenipila. P. insidiosum hyphae are not able to initiate infection without the secretion of hydrolytic enzymes, which are considered an important factor in microbial virulence. AIMS: To evaluate the extracellular enzymatic activity of 14 Brazilian P. insidiosum isolates and a standard strain (ATCC 58637) by the API-ZYM System screening method. METHODS: Zoospores were grown in RPMI 1640 broth, and 65?L of the liquid phase was inoculated in each cupule of the API-ZYM strips. RESULTS: Differences in the enzymatic activities were observed among the isolates, although phosphohydrolases and ester hydrolases were conspicuous among all isolates. ?-glucosidase was also present in most of the isolates. Enzymatic activities of ?-glucosidase and chymotrypsin were not observed, differing from a previous study involving Australian isolates and intracellular enzymes. CONCLUSIONS: The discrepancy in the enzymatic profile observed among Brazilian P. insidiosum isolates reflects the phenotypic variations found in susceptibility tests.

Zanette RA; Ferreiro L; Alves SH; Jesus FP; Lautert C; Spanamberg A; Santurio JM

2013-01-01

120

Control of Pythium Damping-off of Squash (Cucurbita pepo) by Seed Treatment with Crop Straw and Soil by the Biocontrol Agent Trichodema harzianum  

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Full Text Available Seed treatment by non-sterilized powdered straw from 4 crops was tested for Pythium damping-off of squash. The tested straws including wheat, faba bean, soybean and sorghum were effective in controlling the disease in soil artificially infested with Pythium ultinum. Sterilizing straws eliminated the efficacy of these straw, faba bean and soybean straws inhibit the mycelial growth of Pythium more than wheat and sorghum on potato dextrose agar when the straws were mixed with sterilized distilled water and left to ferment for 3 days. The soil treatment by the biocontrol agent T. harzianum control the damping-off disease in artificially infested soil and combination between seed treatment by straw powder and soil treatment by T. harzianum improve the efficacy of the biocontrol agent.

Nahed Z. Haikal

2007-01-01

 
 
 
 
121

Biological control of Pythium aphanidermatum in soilless systems : selection of biocontrol agents and modes of action  

Digital Repository Infrastructure Vision for European Research (DRIVER)

De schimmel Pythium aphanidermatum veroorzaakt wortelrot in o.a. komkommer en is een belangrijke ziekteverwekker in de moderne glastuinbouw. Bestrijdingsmiddelen tegen Pythium zijn verboden. Biologische bestrijding met antagonistische bacteriën is een veelbelovend alternatief. Deze antagonisten moet...

Folman, L.B.

122

New lignan esters from Alyxia schlechteri and antifungal activity against Pythium insidiosum.  

UK PubMed Central (United Kingdom)

Three new lignan esters, alyterinates A-C (1-3), as well as 10 known compounds were isolated from the roots of Alyxia schlechteri. Antifungal activity against Pythium insidiosum of all lignan derivatives was evaluated using disc diffusion assay. P. insidiosum is not a true fungus since its cell walls do not contain ergosterol as usual fungi, so antifungals available now are not effective. From activity testing, it was found that compounds 3, 4 and 5 could inhibit the mycelia growth of P. insidiosum.

Sriphana U; Thongsri Y; Ardwichai P; Poopasit K; Prariyachatigul C; Simasathiansophon S; Yenjai C

2013-08-01

123

New lignan esters from Alyxia schlechteri and antifungal activity against Pythium insidiosum.  

UK PubMed Central (United Kingdom)

Three new lignan esters, alyterinates A-C (1-3), as well as 10 known compounds were isolated from the roots of Alyxia schlechteri. Antifungal activity against Pythium insidiosum of all lignan derivatives was evaluated using disk diffusion assay. P. insidiosum is not a true fungus since its cell walls do not contain ergosterol as usual fungi, so the antifungals available now are not effective. From activity testing, it was found that compounds 3, 4 and 5 could inhibit the mycelia growth of P. insidiosum.

Sriphana U; Thongsri Y; Ardwichai P; Poopasit K; Prariyachatigul C; Simasathiansophon S; Yenjai C

2013-08-01

124

Mixotrophic growth of Nostoc sp. on glucose, sucrose and sugarcane molasses for phycobiliprotein production = Crescimento mixotrófico de Nostoc sp. Glucose, sacarose e melaço de cana-de-açúcar foram testados como substratos para produção de biomassa e ficobiliproteinas  

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Full Text Available Glucose, sacarose, and sugarcane molasses were tested as substrates for production of biomass and phycobiliproteins by Nostoc sp., varying their concentrations in relation to a mineral medium, BG11. All substrates increased the biomass and phycobiliproteins when compared with the control. Sugarcane molasses showed to be thebest substrate for production of both biomass and phycobiliproteins. Greater biomass production occurred in sugarcane molasses 1.0 g L-1 and it was 5.7 times greater than the control. With glucose, it was in 2.5 g L-1 and sucrose, in 1.5 g L-1, reaching 2.5 and 4.8 timesgreater than the control, respectively. For phycobiliproteins, the major production was in sugarcane molasses 1.0 g L-1, 12.5 times greater than the control. With glucose, it was in 1.0 g L-1 and sucrose, in 0,5 g L-1, reaching 3.0 and 4.5 times greater than the control, respectively. The Nostoc sp. assayed can grow mixotrophically, using glucose, sucrose, and sugarcane molasses as organic substrates, and a greater production of biomass andphycobiliproteins can be reached when compared with the autotrophic growth.Todos os substratos aumentaram a biomassa e ficobiliproteinas emrelação ao controle, meio mineral BG11. Melaço de cana-de-açúcar foi o melhor substrato tanto para a produção de biomassa como de ficobiliproteinas. A maior produção de biomassa ocorreu usando melaço de cana-de-açúcar 1,0 g L-1 sendo 5,7 vezes maior que o controle. Com glucose foi em 2,5 g L-1 e sacarose 1,5 g L-1, sendo 2,5 e 4,8 vezes maior que o controle, respectivamente. A maior produção de ficobiliproteinas ocorreu usando melaço de cana-de-açúcar 1,0 g L-1 sendo 12,5 vezes maior que o controle. Com glucose foi em 1,0g L-1 e sacarose 0,5 g L-1, 3,0 e 4,5 vezes maior que o controle, respectivamente. Nostoc sp. testado pode crescer mixotroficamente, usando glucose, sacarose e melaço de cana-deaçúcar como substratos orgânicos, uma maior produção de biomassa e ficobiliproteinaspodendo ser alcançada nessas condições quando comparadas com o crescimento autotrófico.

Raquel Renan Jorge Borsari; Luiz Rodrigo Ito Morioka; Mara Lúcia Luiz Ribeiro; João Batista Buzato; Maria Helena Pimenta Pinotti

2007-01-01

125

40 CFR 180.1275 - Pythium; exception from the requirement of a tolerance.  

Science.gov (United States)

...2010-07-01 2010-07-01 false Pythium; exception from the requirement of a...Exemptions From Tolerances § 180.1275 Pythium; exception from the requirement of a...food/feed commodities, for residues of pythium oligandrum DV 74 when the...

2010-07-01

126

Ethanol fermentation from sugarcane at different maturities  

UK PubMed Central (United Kingdom)

Experiments were done employing cane particles obtained from sugarcane at different growth stages until maturation in order to estimate the sugarcane growth stage where production of ethanol and carbohydrate consumption were optimized. The non-flowering cane variety NA56 was cultivated and samples taken at different time intervals for two consecutive years. Two Saccharomyces cerevisae strains were selected from four strains initially compared. Sucrose was poorly consumed in young cane which was an unexpected result. Fructose on the other hand was the hexose that remained in the medium at the end of fermentations especially when using mature sugarcane. There was an increasing trend in ethanol production as a function of DAP (days after planting) as expected, however a plateau was reached after 225DAP and the maximum value obtained was between 300 and 325DAP. The NA56 cane variety is usually harvested around 350DAP for commercial sugar production. Hence a difference of approximately 25 days less in the field might be needed for maximum ethanol production. On the other hand, it was clear from the data that cane harvesting for ethanol production should not be done after the recommended DAP for commercial sugar production. If this is done, the excess fructose present will not be completely utilized by yeast. Finally it was found that yeasts showing more affinity to sugarcane fibers showed better ethanol yields in all the DAP interval.

Rolz C; de León R

2011-03-01

127

Modelagem do crescimento de cultivares de cana-de-açúcar no período de formação da cultura/ Modeling of growth of sugarcane cultivars during the crop formation period  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese Este estudo teve como objetivo ajustar modelos de crescimento ao acúmulo de matéria seca da parte aérea da cana-de-açúcar durante o período de formação da cultura, para as cultivares RB92579, RB867515, RB928064 e RB855453. Dados de matéria seca foram obtidos durante a execução de experimento em condições de campo entre 26/08/11 e 18/05/12. Os dados experimentais foram coletados a partir dos 45 dias após o plantio, em intervalos de uma ou duas semanas, totali (more) zando 17 datas de amostragem. Os valores obtidos foram submetidos à análise de regressão não linear para determinação dos parâmetros dos modelos expolinear, logístico e Gompertz. Todos os modelos avaliados foram capazes de simular adequadamente o acúmulo de matéria seca pelas cultivares ao longo do período estudado, com valores de coeficiente de determinação ajustados (R²aj) acima de 0,9245. Com base no modelo de crescimento expolinear, constatou-se que, ao final do período experimental, a massa seca foi ligeiramente maior para a cultivar RB855453 em comparação à RB867515, as quais se destacaram em relação às cultivares RB928064 e RB92579. Abstract in english The objective of the present study was to adjust growth models to the above-ground accumulated sugarcane dry matter, during the crop formation period, for cultivars RB92579, RB867515, RB928064 and RB855453. Dry matter data were obtained during the execution of experiment under field conditions from October 26, 2011 to May 18, 2012. Experimental data were collected from 45 days after planting, in one or two week time intervals, totalizing 17 sampling dates. The obtained va (more) lues were subjected to nonlinear regression analysis in order to determine the parameters of the expolinear, logistic and Gompertz models. All evaluated models were capable of adequately simulating the dry matter accumulation by the cultivars during the studied period, with values of the adjusted determination coefficient above 0.9245. Based on the expolinear growth model, it was observed, at the end of the experimental period, that the accumulated dry mass was stightly superior for the cultivar RB855453 as compared to the RB867515, which outperformed the cultivars RB928064 and RB92579.

Batista, Evandro L. da S.; Zolnier, Sérgio; Ribeiro, Aristides; Lyra, Gustavo B.; Silva, Thieres G. F. da; Boehringer, Davi

2013-10-01

128

Development of microsatellite markers for Pythium helicoides.  

UK PubMed Central (United Kingdom)

A strategy combining dual-suppression PCR and thermal asymmetric interlaced PCR was used to determine sequences flanking microsatellite regions in Pythium helicoides. The primer pairs were designed to amplify loci containing (AC)n, (GA)n, (AGC)n, (CAC)n(CAA)n, (TCA)n and (CTTT)n repeats from the P. helicoides nuclear genome. The PCR products of each primer pair, amplified from three representative isolates collected from different hosts and locations, were cloned and sequenced. Different degrees of polymorphism were detected among these microsatellite markers. The numbers of alleles were 6, 2, 4, 11, 4 and 4 in YL-AC, YL-AGC, YL-CAA, YL-CTTT, YL-GA and YL-TCA, respectively. Allele analysis of 30 P. helicoides isolates showed length polymorphisms in all loci, except for YL-AC, using capillary electrophoresis. Thus, we have developed a simple method for designing PCR primers to amplify microsatellite markers from P. helicoides.

Yin-Ling; Zhou W; Motohashi K; Suga H; Fukui H; Kageyama K

2009-04-01

129

Growth and development of Bacillus thuringiensis Cry1Ab-susceptible and Cry1Ab-resistant sugarcane borer on diet and conventional maize plants  

UK PubMed Central (United Kingdom)

The sugarcane borer, Diatraea saccharalis (F.) (Lepidoptera: Crambidae), is a dominant maize borer pest and a major target of Bacillus thuringiensis (Bt)-maize in Louisiana and the Gulf Coast area of Texas (USA). Growth and development of D. saccharalis on non-toxic diet, diet treated with three low concentrations (0.01, 0.05, and 0.1 ?g g?¹) of Cry1Ab toxin, and on non-Bt maize plants were compared for five insect genotypes: a Bt-susceptible strain (BT-SS), a Cry1Ab-resistant strain (BT-RR), a back-crossed and re-selected resistant strain (BT-R'R'), and two F? progeny of the BT-SS and BT-R'R' strains. Fitness of the five genotypes was examined by infesting neonates on diet with/without Cry1Ab toxin in the laboratory and on intact non-Bt maize plants in the greenhouse. Biological parameters measured were neonate-to-pupa development time and pupation rate, larval survival, larval and pupal weight, and sex ratio. Larvae of BT-SS and BT-R'R' on non-toxic diet and non-Bt maize plants grew normally and there were no significant differences between the two strains in all measured parameters, suggesting a lack-of-fitness cost of the Cry1Ab resistance in D. saccharalis. Except for the development time on non-Bt diet, all other parameters on both non-Bt diet and non-Bt maize plants were similar among the five genotypes. Larval development of BT-SS was significantly affected on diet treated with Cry1Ab toxin at 0.05 and 0.1 ?g g?¹, whereas the effect to BT-RR and BT-R'R' was not significant. Pupal weight and sex ratio reared on Cry1Ab-diet were similar and there were no significant differences among the five genotypes. Neonate-to-pupation rate decreased as Cry1Ab concentrations increased but the decrease was more significant for BT-SS than for the other four genotypes. The lack-of-fitness costs of Bt resistance in D. saccharalis imply a greater challenge in managing Bt resistance for this maize borer species.

Wu Xiaoyi; Huang Fangneng; Leonard BRogers; Ghimire Mukti

2009-10-01

130

Zoosporogênese in vitro entre isolados do oomiceto Pythium insidiosum/ In vitro zoosporogenesis among oomycetes Pythium insidiosum isolates  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese Pythium insidiosum é um oomiceto aquático, responsável pela etiologia da pitiose, uma enfermidade crônica, observada freqüentemente em eqüinos. A produção de zoósporos móveis por este microrganismo se constitui no fator determinante da ocorrência da enfermidade. Este estudo avaliou a zoosporogênese e quantificou a produção de zoósporos de 32 amostras de Pythium insidiosum isoladas de eqüinos naturalmente infectados. Pythium insidiosum foi cultivado em meio (more) Corn Meal Agar acrescido de fragmentos de grama, durante 5 dias, a 37°C. Posteriormente, os fragmentos de grama parasitados foram incubados em Meio de Indução a 37°C, por 24 horas. Observou-se que 16 amostras (50%) produziram 20.000 zoósporos mL-1, 12 isolados (37,5%) produziram acima de 20.000 zoósporos mL-1, enquanto quatro amostras (12,5%) produziram menos de 20.000 zoósporos mL-1. O período de maior produção de zoósporos foi entre 6 e 8 horas de incubação. O protocolo utilizado na indução da zoosporogênese mostrou-se eficiente e representa uma importante ferramenta, tanto para a identificação do Pythium insidiosum, como para a obtenção de zoósporos em quantidades suficientes para a inoculação em animais experimentais e aplicação no desenvolvimento de testes de suscetibilidade. Abstract in english Pythium insidiosum is an aquatic oomycete and the etiology of a chronic disease called pythiosis, commonly found in the skin of horses. The production of mobile zoospores by this microorganism is the determinant factor of this disease. This study evaluated the zoosporogenesis and quantification of zoospores in 32 samples of Pythium insidiosum isolated from horses with pythiosis. The assay used culture of the Pythium insidiosum in Corn Meal Agar plus grass blades for 5 day (more) s at 37°C. The grass blades were incubated in Induction Medium at 37°C for 24 hours. The findings showed 16 samples (50%) yielded 20,000 zoospores mL-1, 12 (37.5%) samples yielded over 20,000 zoospores mL-1 and 4 samples (12.5%) yielded less than 20,000 zoospores mL-1. The zoospores production was higher between 6 and 8 hours of incubation. The protocol used in the zoosporogenesis induction was efficient and represents an important tool for Pythium insidiosum identification and the attainment of zoospores in adequate amounts for inoculation in experimental animals and application in the development of susceptibility tests.

Pereira, Daniela Isabel Brayer; Santurio, Janio Morais; Alves, Sydney Hartz; Argenta, Juliana Siqueira; Cavalheiro, Ayrton Sydnei; Ferreiro, Laerte

2008-02-01

131

Zoosporogênese in vitro entre isolados do oomiceto Pythium insidiosum In vitro zoosporogenesis among oomycetes Pythium insidiosum isolates  

Directory of Open Access Journals (Sweden)

Full Text Available Pythium insidiosum é um oomiceto aquático, responsável pela etiologia da pitiose, uma enfermidade crônica, observada freqüentemente em eqüinos. A produção de zoósporos móveis por este microrganismo se constitui no fator determinante da ocorrência da enfermidade. Este estudo avaliou a zoosporogênese e quantificou a produção de zoósporos de 32 amostras de Pythium insidiosum isoladas de eqüinos naturalmente infectados. Pythium insidiosum foi cultivado em meio Corn Meal Agar acrescido de fragmentos de grama, durante 5 dias, a 37°C. Posteriormente, os fragmentos de grama parasitados foram incubados em Meio de Indução a 37°C, por 24 horas. Observou-se que 16 amostras (50%) produziram 20.000 zoósporos mL-1, 12 isolados (37,5%) produziram acima de 20.000 zoósporos mL-1, enquanto quatro amostras (12,5%) produziram menos de 20.000 zoósporos mL-1. O período de maior produção de zoósporos foi entre 6 e 8 horas de incubação. O protocolo utilizado na indução da zoosporogênese mostrou-se eficiente e representa uma importante ferramenta, tanto para a identificação do Pythium insidiosum, como para a obtenção de zoósporos em quantidades suficientes para a inoculação em animais experimentais e aplicação no desenvolvimento de testes de suscetibilidade.Pythium insidiosum is an aquatic oomycete and the etiology of a chronic disease called pythiosis, commonly found in the skin of horses. The production of mobile zoospores by this microorganism is the determinant factor of this disease. This study evaluated the zoosporogenesis and quantification of zoospores in 32 samples of Pythium insidiosum isolated from horses with pythiosis. The assay used culture of the Pythium insidiosum in Corn Meal Agar plus grass blades for 5 days at 37°C. The grass blades were incubated in Induction Medium at 37°C for 24 hours. The findings showed 16 samples (50%) yielded 20,000 zoospores mL-1, 12 (37.5%) samples yielded over 20,000 zoospores mL-1 and 4 samples (12.5%) yielded less than 20,000 zoospores mL-1. The zoospores production was higher between 6 and 8 hours of incubation. The protocol used in the zoosporogenesis induction was efficient and represents an important tool for Pythium insidiosum identification and the attainment of zoospores in adequate amounts for inoculation in experimental animals and application in the development of susceptibility tests.

Daniela Isabel Brayer Pereira; Janio Morais Santurio; Sydney Hartz Alves; Juliana Siqueira Argenta; Ayrton Sydnei Cavalheiro; Laerte Ferreiro

2008-01-01

132

Cotton Seedling Preemergence Damping-Off Incited by Rhizopus oryzae and Pythium spp. and Its Biological Control with Trichoderma spp.  

UK PubMed Central (United Kingdom)

ABSTRACT Planting the cotton cv. Sure-Grow 747 in cotton seedling disease plots during the 2001 growing season resulted in high levels of preemergence damping-off among the seedlings. Four cotton pathogens, Pythium aphanidermatum, P. ultimum, an unidentified Pythium sp., and Rhizopus oryzae, were isolated from diseased seed embryos and seedlings. Disease incited by the Pythium spp. could be controlled by seed treatment with Metalaxyl, but disease incited by R. oryzae could not. Seed treatment with Metalaxyl in naturally infested field soil was only partially effective; therefore, symptoms in 47% of the diseased seedlings could be attributed to R. oryzae. Susceptibility to disease appeared to be related to release in the spermosphere, by the germinating seeds, of compounds that stimulate pathogen propagule germination, because exudates from seed of the suscept Sure-Grow 747 and extracts from wheat bran induced pathogen germination and growth, whereas exudates from resistant cv. Stoneville 213 did not. However, even Stoneville 213 became susceptible when infested soil was amended with wheat bran. Seed treatment with preparations of Trichoderma virens parent, mutant, and hybrid strains gave effective biological control of preemergence damping-off. Disease control was attributable to metabolism by the biocontrol agent of pathogen germination stimulants released by the seed, because amendment of pathogen-infested soil with the propagule germination stimulants in wheat bran negated the protective effect of the seed treatment.

Howell CR

2002-02-01

133

Ginsenosidases and the pathogenicity of Pythium irregulare.  

Science.gov (United States)

American ginseng (Panax quinquefolius L.) produces triterpenoid saponins, ginsenosides, that possess mild fungitoxic activity toward some common ginseng leaf pathogens. However, numerous oomycete root pathogens of ginseng, most notably Pythium irregulare Buisman, are able to partially deglycosylate 20 (S)-protopanaxadiol ginsenosides Rb1, Rd and gypenoside XVII via extracellular glycosidases, leading to a common product, ginsenoside F2. Conversion of the common 20 (S)-protopanaxadiols into F2 requires both ? (1?6) and ? (1?2) glucosidase activity. In the present study, the ability of nine distinct isolates of P. irregulare, as well as a P. ultimum Trow isolate and two isolates of Trichoderma hamatum (Bonord.) Bainier, to deglycosylate 20 (S)-protopanaxadiols, in vitro was examined. The pathogenicity of each isolate was also examined by scoring the severity of disease symptoms caused by each in separate inoculations of one- and two-year old ginseng seedlings. Disease severity was scored using a disease severity index, as well as by taking F(v)/F(m) measurements of leaves during a 14-day infection period. Based on these measurements, it was concluded that (1) the use of direct F(v)/F(m) measurements correlates strongly with observations of disease severity (R(2)=0.79), and that (2) the pathogenicity of P. irregulare isolates correlates with their ability to deglycosylate ginsenosides (R(2)=0.57). These results further support the hypothesis that the pathogenicity of P. irregulare on ginseng roots is dependent, in part, on the ability of this organism to deglycosylate ginsenosides. PMID:22521132

Ivanov, Dimitre A; Bernards, Mark A

2012-04-19

134

Ginsenosidases and the pathogenicity of Pythium irregulare.  

UK PubMed Central (United Kingdom)

American ginseng (Panax quinquefolius L.) produces triterpenoid saponins, ginsenosides, that possess mild fungitoxic activity toward some common ginseng leaf pathogens. However, numerous oomycete root pathogens of ginseng, most notably Pythium irregulare Buisman, are able to partially deglycosylate 20 (S)-protopanaxadiol ginsenosides Rb1, Rd and gypenoside XVII via extracellular glycosidases, leading to a common product, ginsenoside F2. Conversion of the common 20 (S)-protopanaxadiols into F2 requires both ? (1?6) and ? (1?2) glucosidase activity. In the present study, the ability of nine distinct isolates of P. irregulare, as well as a P. ultimum Trow isolate and two isolates of Trichoderma hamatum (Bonord.) Bainier, to deglycosylate 20 (S)-protopanaxadiols, in vitro was examined. The pathogenicity of each isolate was also examined by scoring the severity of disease symptoms caused by each in separate inoculations of one- and two-year old ginseng seedlings. Disease severity was scored using a disease severity index, as well as by taking F(v)/F(m) measurements of leaves during a 14-day infection period. Based on these measurements, it was concluded that (1) the use of direct F(v)/F(m) measurements correlates strongly with observations of disease severity (R(2)=0.79), and that (2) the pathogenicity of P. irregulare isolates correlates with their ability to deglycosylate ginsenosides (R(2)=0.57). These results further support the hypothesis that the pathogenicity of P. irregulare on ginseng roots is dependent, in part, on the ability of this organism to deglycosylate ginsenosides.

Ivanov DA; Bernards MA

2012-06-01

135

Species of Phytophthora and Pythium as Nematode-destroying Fungi  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Pythium monospermum,, P. aphanidermatum, and Phytophthora palmivora were found to be capable of destroying certain nonstylet-bearing nematodes through endozoic parasitism by hyphae from ingested zoospores. Hyphae of P. monospermum parasitized nematode eggs but could not capture or otherwise prey upo...

Tzean, S. S.; Estey, R. H.

136

Further Studies on Sterol Stimulation of Sexual Reproduction in Pythium.  

Science.gov (United States)

The influence of amino acids on the stimulatory activity of cholesterol on the production of oogonia by a species of Pythium is reported. None of the sterols tested was metabolized by the fungus, but the sterols which do affect oogonia production were ads...

J. H. Sietsma R. H. Haskins

1966-01-01

137

Effect of chitosan on cucumber plants: suppression of Pythium aphanidermatum and induction of defense reactions.  

UK PubMed Central (United Kingdom)

Biological activity of chitosan on Pythium rot of cucumber was investigated. Growing cucumber plants in the presence of chitosan 100 or 400 microgram/ml) controlled root rot caused by Pythium aphanidermatum and triggered several host defense responses, including the induction of structural barriers in root tissues and the stimulation of antifungal hydrolases (chitinase, chitosanase, and beta-1,3-glucanase) in both the roots and leaves. Whereas chitosan did not cause any apparent phytotoxicity to cucumber plants, it adversely affected the growth of P. aphanidermatum. A close examination of hyphal cells revealed that chitosan caused wall loosening, vacuolation, and, in some cases, protoplasm disintegration. This may, in part, explain the limited ability of the pathogen to colonize root tissues in the presence of chitosan. Ultrastructural study of root tissue from chitosan-treated plants showed that fungal cells were mainly restricted to root surfaces. The interplay of the antifungal and eliciting properties of chitosan makes chitosan a potential antifungal agent for the control of root rot of cucumber caused by P. aphanidermatum.

El Ghaouth A; Arul J; Grenier J; Benhamou N; Asselin A; Belanger R

1994-03-01

138

Insights into the molecular mechanism of tolerance to carboxylic acid amide (CAA) fungicides in Pythium aphanidermatum.  

UK PubMed Central (United Kingdom)

BACKGROUND: Tolerance to the oomycete-specific carboxylic acid amide (CAA) fungicides is a poorly understood mechanism in Pythium species. The root-rot and damping-off causative agent Pythium aphanidermatum and the CAA fungicide mandipropamid (MPD) were used to investigate the molecular basis of CAA tolerance. RESULTS: Five genes putatively involved in carbohydrate synthesis were identified and characterised: one chitin synthase gene, PaChs, and four cellulose synthase genes PaCesA1 to PaCesA4, of which PaCesA3 encodes the MPD target enzyme. These genes were differentially expressed throughout the life cycle of P. aphanidermatum. Mycelium treated with MPD concentrations slightly affecting mycelial growth did not cause a change in PaCesA3 expression nor a strong upregulation of PaCesA homologues. The high tolerance level of P. aphanidermatum and the lack of PaCesA upregulation imply that MPD tolerance is the result of a specific amino acid configuration in the cellulose synthase 3 (CesA3) target enzyme. Indeed, P. aphanidermatum displays the amino acid L1109 which is also associated with MPD resistance in artificial mutants of Phytophthora species. CONCLUSION: It is concluded that MPD tolerance in P. aphanidermatum is not caused by compensatory mechanisms but most likely by an inherent target-site configuration in PaCesA3 that hinders MPD binding to the enzyme pocket.

Blum M; Gisi U

2012-08-01

139

Life table studies of Elasmopalpus lignosellus (Lepidoptera: Pyralidae) on sugarcane.  

UK PubMed Central (United Kingdom)

The lesser cornstalk borer, Elasmopalpus lignosellus (Zeller) (Lepidoptera: Pyralidae) is an important pest of sugarcane (a complex hybrid of Saccharum spp.) in southern Florida. Reproductive and life table parameters for E. lignosellus were examined at nine constant temperatures from 13 to 36 °C with sugarcane as the larval food source. The pre- and postoviposition periods decreased with increasing temperatures and reached their minimums at 33 and 36 °C, respectively. The oviposition period was longest at 27 °C. The mean fecundity, stage-specific survival, stage-specific fecundity, intrinsic rate of increase, and finite rate of increase were greatest at 30 °C and decreased with increasing or decreasing temperature. The net reproductive rate was greatest at 27 °C. The Logan-6 model best described the relationship between temperature and intrinsic rate of increase. The generation and population doubling times were longest at 13 and shortest at 33 and 30 °C, respectively. The most favorable temperatures for E. lignosellus population growth were between 27 and 33°C. Life table parameters for E. lignosellus reared on sugarcane were greater than for the Mexican rice borer [Eoreuma loftini (Dyar) (Lepidoptera: Crambidae)] reared on an artificial diet at 30 °C. The intrinsic rates of increase for the sugarcane borer [Diatraea saccharalis (F.) (Lepidoptera: Crambidae)] reared on sugarcane or corn were the same as for E. lignosellus reared on sugarcane at 27 °C, but the net reproductive rate was four times higher for the former than the latter borer species.

Sandhu HS; Nuessly GS; Webb SE; Cherry RH; Gilbert RA

2010-12-01

140

Life table studies of Elasmopalpus lignosellus (Lepidoptera: Pyralidae) on sugarcane.  

Science.gov (United States)

The lesser cornstalk borer, Elasmopalpus lignosellus (Zeller) (Lepidoptera: Pyralidae) is an important pest of sugarcane (a complex hybrid of Saccharum spp.) in southern Florida. Reproductive and life table parameters for E. lignosellus were examined at nine constant temperatures from 13 to 36 °C with sugarcane as the larval food source. The pre- and postoviposition periods decreased with increasing temperatures and reached their minimums at 33 and 36 °C, respectively. The oviposition period was longest at 27 °C. The mean fecundity, stage-specific survival, stage-specific fecundity, intrinsic rate of increase, and finite rate of increase were greatest at 30 °C and decreased with increasing or decreasing temperature. The net reproductive rate was greatest at 27 °C. The Logan-6 model best described the relationship between temperature and intrinsic rate of increase. The generation and population doubling times were longest at 13 and shortest at 33 and 30 °C, respectively. The most favorable temperatures for E. lignosellus population growth were between 27 and 33°C. Life table parameters for E. lignosellus reared on sugarcane were greater than for the Mexican rice borer [Eoreuma loftini (Dyar) (Lepidoptera: Crambidae)] reared on an artificial diet at 30 °C. The intrinsic rates of increase for the sugarcane borer [Diatraea saccharalis (F.) (Lepidoptera: Crambidae)] reared on sugarcane or corn were the same as for E. lignosellus reared on sugarcane at 27 °C, but the net reproductive rate was four times higher for the former than the latter borer species. PMID:22182570

Sandhu, Hardev S; Nuessly, Gregg S; Webb, Susan E; Cherry, Ronald H; Gilbert, Robert A

2010-12-01

 
 
 
 
141

Recombinant expression and biochemical characterization of sugarcane legumain.  

UK PubMed Central (United Kingdom)

Plant legumains, also termed vacuolar processing enzymes (VPEs), are cysteine peptidases that play key roles in plant development, senescence, programmed cell death and defense against pathogens. Despite the increasing number of reports on plant cysteine peptidases, including VPEs, the characterization of sugarcane VPEs and their inhibition by endogenous cystatins have not yet been described. This is the first report of the biochemical characterization of a sugarcane cysteine peptidase. In this work, a recombinant sugarcane legumain was expressed in Pichia pastoris and characterized. Kinetic studies of the recombinant CaneLEG revealed that this enzyme has the main characteristics of VPEs, such as self-activation and activity under acidic pH. CaneLEG activity was strongly inhibited when incubated with sugarcane cystatin 3 (CaneCPI-3). Quantitative analysis of CaneLEG and CaneCPI-3 gene expression indicated a tissue-specific expression pattern for both genes throughout sugarcane growth, with the strong accumulation of CaneLEG transcripts throughout the internode development. Furthermore, the CaneLEG and CaneCPI-3 genes exhibited up-regulation in plantlets treated with abscisic acid (ABA). These results suggest that CaneCPI-3 may be a potential endogenous inhibitor of CaneLEG and these genes may be involved in plant stress response mediated by ABA. Also, the expression analysis provides clues for the putative involvement of CaneLEG and CaneCPI-3 in sugarcane development and phytohormone response.

Santos-Silva LK; Soares-Costa A; Gerald LT; Meneghin SP; Henrique-Silva F

2012-08-01

142

Recombinant expression and biochemical characterization of sugarcane legumain.  

Science.gov (United States)

Plant legumains, also termed vacuolar processing enzymes (VPEs), are cysteine peptidases that play key roles in plant development, senescence, programmed cell death and defense against pathogens. Despite the increasing number of reports on plant cysteine peptidases, including VPEs, the characterization of sugarcane VPEs and their inhibition by endogenous cystatins have not yet been described. This is the first report of the biochemical characterization of a sugarcane cysteine peptidase. In this work, a recombinant sugarcane legumain was expressed in Pichia pastoris and characterized. Kinetic studies of the recombinant CaneLEG revealed that this enzyme has the main characteristics of VPEs, such as self-activation and activity under acidic pH. CaneLEG activity was strongly inhibited when incubated with sugarcane cystatin 3 (CaneCPI-3). Quantitative analysis of CaneLEG and CaneCPI-3 gene expression indicated a tissue-specific expression pattern for both genes throughout sugarcane growth, with the strong accumulation of CaneLEG transcripts throughout the internode development. Furthermore, the CaneLEG and CaneCPI-3 genes exhibited up-regulation in plantlets treated with abscisic acid (ABA). These results suggest that CaneCPI-3 may be a potential endogenous inhibitor of CaneLEG and these genes may be involved in plant stress response mediated by ABA. Also, the expression analysis provides clues for the putative involvement of CaneLEG and CaneCPI-3 in sugarcane development and phytohormone response. PMID:22721948

Santos-Silva, Ludier K; Soares-Costa, Andrea; Gerald, Lee T S; Meneghin, Silvana P; Henrique-Silva, Flavio

2012-05-29

143

SUGARCANE YELLOW LEAF DISEASE  

Science.gov (United States)

Sugarcane yellow leaf was first recognized in Florida in 1994. Yellow leaf is caused by a virus that is transmitted in a persistent manner by aphids. The primary symptoms of yellow leaf are the yellowing of the underside of the midrib of leaves 3 to 6 counting from the top expanding spindle leaf. ...

144

Small sugarcane peeler  

UK PubMed Central (United Kingdom)

The utility model discloses a small sugarcane peeler, which mainly comprises a power system, a transmission system, a peeling system, a feeding system, a flexible hold-down system and a supporting and protecting chassis system. The system creatively utilizes a planetary gear train to simultaneously carry out the main rotational movement and circumferential feeding movement of a tool, the structure is simple, and the peeling efficiency is high moreover, the planetary mechanism applies crossed gear transmission to realize angled transmission, so that the transmission mechanism is more compact and the system also creatively combines the end surface screw thread with the gear to realize crossed-axes transmission, thus achieving an axial automatic feeding function for variable-diameter sugarcanes. The small sugarcane peeler resolves the defects of the traditional manual longitudinal peeling method and the profiling radius milling cutter peeling method, greatly reduces the labor intensity of operators and increases the efficiency and effect of peeling. The small sugarcane peeler has the advantages of simple structure, safe and reliable action, convenient operation and low manufacturing cost and can be widely popularized.

BAOHUA YU; XIAOPING HU; HUI LIN; WEIDOU ZHAO; HUAFENG QIU; WENFU DENG

145

Sugarcane bio ethanol and bioelectricity  

Energy Technology Data Exchange (ETDEWEB)

This chapter approaches the Brazilian sugar cane production and processing model, sugarcane processing, sugarcane reception, sugarcane preparation and juice extraction, juice treatment, fermentation, distillation, sector efficiencies and future improvement - 2007, 2015 and 2025, present situation (considering the 2007/2008 harvesting season), prospective values for 2015 and for 2025, bioelectricity generation, straw recovery, bagasse availability, energy balance, present situation, perspective for improvements in the GHG mitigation potential, bio ethanol production chain - from field to tank, and surplus electricity generation.

Nogueira, Luiz Augusto Horta; Leal, Manoel Regis Lima Verde

2012-07-01

146

A new species of Pythium with inflated sporangia and coiled antheridia, isolated from India.  

UK PubMed Central (United Kingdom)

Pythium kashmirense sp. nov. was isolated from soil samples taken on the Himalayas at the height of 5300 feet in the Shivalik Hill Range of the northern Indian state of Jammu and Kashmir. The oomycete has filamentous-inflated type sporangia and its antheridial filaments form loose loops around the female gametangia, and coil around the oogonial stalks. The new species is closely related to Pythium plurisporium, Pythium periilum, Pythium inflatum, and Pythium folliculosum. All of these oomycetes have filamentous-inflated type sporangia. However, P. kashmirense has its own distinguishing characteristics which can easily differentiate it among these related species. The sequences of the internal transcribed spacer (ITS) region of its rRNA and its morphological characters are unique for the genus Pythium. Taxonomic description of this new species, its comparison with related oomycetes and the sequence of the ITS region of its rRNA, are discussed here.

Paul B; Bala K

2008-05-01

147

Diversity of the Pythium community infecting crown and roots apple in Tunisia  

Directory of Open Access Journals (Sweden)

Full Text Available The genus Pythium is important in agriculture, since it contains many plantpathogenic species. Little is known about the diversity of Pythium species causing appledicline. Therefore, the aim of the study was to characterize 21 Pythium isolates collectedfrom root and collar rot apple trees in Tunisia from 2006 through to 2009. The isolateswere characterized morphologically as well as through sequence analyze of the internaltranscribed spacer region (ITS). Three Pythium species were identified in this study P.rostratifingens, P. undulatum and P. sterilum. In virulence assays on excised apple twigsand in the fields, representative isolates of the different Pythium species isolated werepathogenic on the Anna, Lorka and Meski varieties and the MM106 rootstock. Resultsobtained show the great susceptibility of the MM106 rootstock to the infections for thedifferent Pythium species tested.

Souli M; N. Boughalleb; P. Abad-Campos; L.A. Álvarez; A. Pérez-Sierra; J. Armengol; J. García-Jiménez; M.S. Romdhani

2011-01-01

148

Pythium cederbergense sp. nov. and related taxa from Pythium clade G associated with the South African indigenous plant Aspalathus linearis (rooibos).  

UK PubMed Central (United Kingdom)

The genus Pythium consists of more than 120 species and is subdivided into 11 phylogenetic clades (A-K) based on internal transcribed spacer (ITS) region sequence data. Pythium clade G contains only seven known species, with most not being well described. Our study characterized 12 Pythium isolates from Aspalathus linearis (rooibos) that fit into clade G. Phylogenetic analyses of the ITS region and a combined phylogeny of four gene regions (ITS, ?-tubulin, COX1 and COX2 [cytochrome c oxidase subunits I, II]) identified five clade G subclades. The rooibos isolates formed two groups, Pythium Rooibos I (RB I) and II (RB II), that clustered into two separate clades within subclade 1. The nine Pythium RB I isolates formed a distinct clade from P. iwayamai and is described here as a new species, Pythium cederbergense sp. nov. The three Pythium RB II isolates had P. canariense and P. violae as their closest relatives and were genetically diverse, suggesting the presence of several new species or a species complex that cannot be resolved with the current data, thus precluding a species description of this group. Morphological analyses showed that P. cederbergense and Pythium RB II were indistinguishable from each other but distinct from known clade G species. Clade G studies are being hampered by imprecise morphological descriptions of P. violae, P. canariense and P. iwayamai and each species being represented by only one isolate. The P. cederbergense and Pythium RB II isolates all were nonpathogenic toward rooibos, lupin and oats seedlings. One oligonucleotide was developed for each of P. cederbergense and Pythium RB II, which was able to differentiate the isolates with DNA macro-array analyses.

Bahramisharif A; Lamprecht SC; Spies CF; Botha WJ; McLeod A

2013-09-01

149

Pythium cederbergense sp. nov. and related taxa from Pythium clade G associated with the South African indigenous plant Aspalathus linearis (rooibos).  

Science.gov (United States)

The genus Pythium consists of more than 120 species, and is subdivided into eleven phylogenetic clades (A to K) based on internal transcribed spacer (ITS) region sequence data. Pythium clade G only contains seven known species, with most not being well described. Our study characterized 12 Pythium isolates from Aspalathus linearis (rooibos) that fit into clade G. Phylogenetic analyses of the ITS region and a combined phylogeny of four gene regions (ITS, ?-tubulin and, COX1 and COX2 [cytochrome c oxidase subunits I and II]) identified five clade G sub-clades. The rooibos isolates formed two groups, Pythium Rooibos group I (RB I) and II (RB II) that clustered into two separate clades within sub-clade 1. The nine Pythium RB I isolates formed a distinct clade from P. iwayamai and is described here as a new species, Pythium cederbergense sp. nov. The three Pythium RB II isolates had P. canariense and P. violae as their closest relatives and were genetically diverse, suggesting the presence of several new species or a species complex that cannot be resolved with the current data, thus precluding a species description of this group. Morphological analyses showed that P. cederbergense and Pythium RB II were indistinguishable from each other, but distinct from known clade G species. Clade G studies are being hampered by imprecise morphological descriptions of P. violae, P. canariense and P. iwayamai, and each species only being represented by one isolate. The P. cederbergense and Pythium RB II isolates were all non-pathogenic toward rooibos, lupin and oats seedlings. One oligonucleotide was developed for each of P. cederbergense and Pythium RB II, which was able to differentiate the isolates using DNA macroarray analyses. PMID:23709523

Bahramisharif, Amirhossein; Lamprecht, Sandra; Spies, Chris; Botha, Wilhelm; McLeod, Adele

2013-05-25

150

Pythium cederbergense sp. nov. and related taxa from Pythium clade G associated with the South African indigenous plant Aspalathus linearis (rooibos).  

UK PubMed Central (United Kingdom)

The genus Pythium consists of more than 120 species, and is subdivided into eleven phylogenetic clades (A to K) based on internal transcribed spacer (ITS) region sequence data. Pythium clade G only contains seven known species, with most not being well described. Our study characterized 12 Pythium isolates from Aspalathus linearis (rooibos) that fit into clade G. Phylogenetic analyses of the ITS region and a combined phylogeny of four gene regions (ITS, ?-tubulin and, COX1 and COX2 [cytochrome c oxidase subunits I and II]) identified five clade G sub-clades. The rooibos isolates formed two groups, Pythium Rooibos group I (RB I) and II (RB II) that clustered into two separate clades within sub-clade 1. The nine Pythium RB I isolates formed a distinct clade from P. iwayamai and is described here as a new species, Pythium cederbergense sp. nov. The three Pythium RB II isolates had P. canariense and P. violae as their closest relatives and were genetically diverse, suggesting the presence of several new species or a species complex that cannot be resolved with the current data, thus precluding a species description of this group. Morphological analyses showed that P. cederbergense and Pythium RB II were indistinguishable from each other, but distinct from known clade G species. Clade G studies are being hampered by imprecise morphological descriptions of P. violae, P. canariense and P. iwayamai, and each species only being represented by one isolate. The P. cederbergense and Pythium RB II isolates were all non-pathogenic toward rooibos, lupin and oats seedlings. One oligonucleotide was developed for each of P. cederbergense and Pythium RB II, which was able to differentiate the isolates using DNA macroarray analyses.

Bahramisharif A; Lamprecht S; Spies C; Botha W; McLeod A

2013-05-01

151

Sugarcane micropropagation using light emitting diodes and adjustment in growth-medium sucrose concentration/ Micropropagação de cana-de-açúcar com diodos emissores de luz e ajuste da concentração de sacarose do meio de cultivo  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese O objetivo deste trabalho foi avaliar o uso de diodos emissores de luz (LEDs) em substituição a lâmpadas fluorescentes brancas e adequar a concentração de sacarose na micropropagação de cana-de-açúcar (Saccharum officinarum L.). Brotações da variedade RB 872552 foram avaliadas nas fases de multiplicação e enraizamento, utilizando as fontes de luz LEDs azuis, LEDs vermelhos, LEDs verdes, lâmpadas Growlux e lâmpadas fluorescentes brancas, e as concentrações (more) de sacarose de 0, 15, 30 e 45g L-1, fixando-se a intensidade luminosa em 20µmol m-2 s-1. Os tratamentos foram dispostos em delineamento inteiramente ao acaso, em fatorial 5x4 (fontes de luz x concentrações de sacarose). O desenvolvimento das brotações foi satisfatório sob os três tipos de LEDs estudados. A presença de sacarose no meio de cultivo foi indispensável para multiplicação e enraizamento das brotações, sendo necessário ajuste da concentração para cada fonte de luz. Os LEDs vermelhos não proporcionaram a maior taxa de multiplicação, porém esta foi bastante alta (8,5 brotos por subcultivo, com adição de 34,9g L-1 de sacarose), com maior comprimento dos brotos (33,3mm) e maior eficiência de aclimatização das plantas. Concluiu-se que os LEDs podem ser utilizados como substitutos das lâmpadas fluorescentes em laboratórios de micropropagação de cana-de-açúcar. Abstract in english The aim of this research was to evaluate the use of light emitting diodes (LEDs) instead of white fluorescent lamps as light source and adequate growth-medium sucrose concentration for sugarcane micropropagation (Saccharum officinarum L.). Sugarcane (RB 872552 variety) bud explants were evaluated during the multiplication and rooting phases under controlled growth-room conditions. Different light sources (blue, red and green LEDs; Growlux and white fluorescent lamps) and (more) different medium sucrose concentrations (0; 15; 30 and 45g L-1) were used, maintaining constant light intensity (20µmol m-2 s-1), photoperiod (16h) and temperature (25+2°C). The experiment was a completely randomized design, and treatments were arranged in a 5x4 factorial (five light sources and four medium sucrose concentrations) with six replications. Sugarcane bud growth was satisfactory under the three LED types studied. The presence of sucrose in growth media was essential for bud multiplication and rooting. Nevertheless, each light source requires the respective medium sucrose concentration adjustment for best results. Red LEDs provided a significantly high multiplication rate (although not the highest) with 8.5 buds per sub-culture and 34.9g L-1 of sucrose; also, the highest bud length (33.3mm) and the best plantlet acclimatization. Therefore, LED sources can advantageously substitute fluorescent lamps in laboratories of sugarcane micropropagation.

Rocha, Paulo Sérgio Gomes da; Oliveira, Roberto Pedroso de; Scivittaro, Walkyria Bueno

2013-07-01

152

Sugarcane Yield, Sugarcane Quality, and Soil Variability in Louisiana  

Science.gov (United States)

This study reports results from our evaluations of the spatial variability of sugarcane (interspecific hybrids of Saccharum spp.) yield and quality in relation to soil chemical properties in Southern Louisiana. Sugarcane cv 'LCP 85-384' was grown in two locations, Rebecca Plantation at Schriever, L...

153

Sugarcane Improvement Through Breeding and Biotechnology  

Science.gov (United States)

The advancements in sugarcane breeding and the improvement of sugarcane through biotechnology have been reviewed by a team of leading sugarcane specialists from around the world. Topics covered in the breeding section include the evolution and origin of sugarcane, early history of conventional sugar...

154

Toll-deficient Drosophila is susceptible to Pythium insidiosum infection.  

Science.gov (United States)

There is a paucity of animal models of pythiosis, a life-threatening disease of humans and animals, the immunopathogenesis of which is poorly understood. A pythiosis model was developed by injecting Toll (Tl)-deficient Drosophila melanogaster flies with Pythium insidiosum zoospores. The infected Tl mutant flies had significantly lower survival rates (73.7%) than did control flies. This study reveals the important role of Tl pathway activation in fly immune response to pythiosis. PMID:23865688

Zanette, Régis A; Santurio, Janio M; Loreto, Erico S; Alves, Sydney H; Kontoyiannis, Dimitrios P

2013-10-01

155

Toll-deficient Drosophila is susceptible to Pythium insidiosum infection.  

UK PubMed Central (United Kingdom)

There is a paucity of animal models of pythiosis, a life-threatening disease of humans and animals that has poorly understood immunopathogenesis. We developed a pythiosis model by injecting Pythium insidiosum zoospores in Toll (Tl)-deficient Drosophila melanogaster flies. The infection of Tl mutant flies resulted in significantly lower survival rates (73.7%) when compared to control flies. Our study reveals the important role of Tl pathway activation in fly immune response to pythiosis.

Zanette RA; Santurio JM; Loreto ES; Alves SH; Kontoyiannis DP

2013-07-01

156

Pythium aphanidermatum (Edson) Fitzp. a pathogen of greenhouse cucumbers  

Directory of Open Access Journals (Sweden)

Full Text Available The infection of mature cucumber plants by Pythium aphanidermatum was stated in two greenhouses. Young cucumber plants from the stage of young seedling until the beginning of cropping were easily infected by the fungus when artificially inoculated. The mature plants were effectively infected only when high temperature (above 30°C) and high moisture conditions were provided. All 17 cucumber varieties tested were susceptible to infection. Morphology of the fungus is described for the first time in Poland.

Bogdan Nowicki

1982-01-01

157

Biocontrol of damping off of tomato caused by Pythium aphanidermatum  

Directory of Open Access Journals (Sweden)

Full Text Available Damping-off of tomato caused by Pythium aphanidermatum was reduced by the application of talc based formulation of Trichoderma viride and Pseudomonas fluorescens in nursery beds before sowing. Besides reducing the pre - and post-emergence damping off these antagonists' increased the root length, shoot length and biomass production of tomato seedlings. These antagonists significantly reduced the population of P. aphanidermatum in soil.

S.K. MANORANTITHAM, V.PRAKASAM and K. RAJAPPAN

2012-01-01

158

Antagonistic Potential of Iranian Native Streptomyces Strains in Biocontrol of Pythium aphanidermatum  

Directory of Open Access Journals (Sweden)

Full Text Available Pythium aphanidermatum, the major phytopathogen induce damping off, root and stem rots, blights of grasses and fruit and in greenhouse cucurbits growing all areas of the world. Soil Actinomycetes including 178 isolates were assayed for assessing antagonistic activity against P.aphanidermatum. From tested isolates, 43 isolates were effective but 2 isolates strains 311 and 321 showed high anti-fungal activity revealed by bioassays in agar disk and well diffusion methods. For further biological characterizations, the active strains were grown in submerged cultures to determine growth curve and prepare crude extracts. Preliminary greenhouse studies indicated that amending soil with these strains, 311 and 321; reduce crop losses due to the pathogen. Antifungal activities of both antagonists were of fungicidal type on pathogen with complete inhibitory effects.

F. Sharifi; G.H. Shahidi Bonjar; S. Aghighi; P. Rashid Farrokhi; E. Khalesi; M.J. Mahdavi; H. Taraz

2007-01-01

159

IDENTIFICATION OF PYTHIUM SPECIES ON WEST TEXAS PEANUTS AND SENSITIVITY OF ISOLATES TO MEFENOXAM AND AZOXYSTROBIN IN PETRI DISH ASSAYS.  

Science.gov (United States)

A survey was conducted in 107 peanut fields to determine the incidence of Rhizoctonia or Pythium pod rot. Rhizoctonia solani and Pythium spp. were isolated from rotted pods in 35 and 39% of the fields, respectively. Isolates of Pythium were collected and some were identified to species. The three...

160

EVALUATION OF ADAPTED WHEAT CULTIVARS FOR TOLERANCE TO PYTHIUM ROOT ROT  

Science.gov (United States)

To date, no source of genetic resistance has been identified against Pythium species, a major root fungal pathogen of wheat (Triticum aestivum L.). In addition, no long-term, sustainable options for controlling Pythium root rot are available; therefore, identifying and then incorporating genetic re...

 
 
 
 
161

Metalaxyl-M-Resistant Pythium Species in Potato Cropping Systems in the Pacific Northwest, USA  

Science.gov (United States)

Several Pythium spp. causing leak on potato (Solanum tuberosum) are managed by the systemic fungicide metalaxyl-M (mefenoxam). Metalaxyl-M-resistant (MR) isolates of Pythium spp. have been identified in potato production areas of the U.S, but detailed information on the occurrence of resistance is ...

162

Fungus gnats and Pythium in the attack on greenhouse plants: conspirators or just cohabitants  

Science.gov (United States)

Research conducted by collaborating Cornell University and USDA-ARS scientists investigated the potential for fungus gnats to vector Pythium root-rot pathogens. Fungus gnat larvae readily consumed Pythium oospores; the spores survived passage through the larval gut and, upon defecation, were able to...

163

Effect of Soil Acidity on Diseases Caused by Pythium ultimum and Fusarium oxysporum on Tomato Plants  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Pythium ultimum and Fusarium oxysporum are important pathogens in agriculture crops and cause serious diseases that resulted in reducing the yield of many crops. The effect of soil acidity on the occurrence and severity of diseases caused by Pythium ultimum and Fusarium ox...

Khalaf M. Alhussaen

164

Trehalose induces antagonism towards Pythium debaryanum in Pseudomonas fluorescens ATCC 17400.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Pseudomonas fluorescens ATCC 17400 shows in vitro activity against Pythium debaryanum under conditions of iron limitation. A lacZ reporter gene introduced by transposon mutagenesis into the P. fluorescens ATCC 17400 trehalase gene (treA) was induced by a factor released by the phytopathogen Pythium ...

Gaballa, A; Abeysinghe, P D; Urich, G; Matthijs, S; De Greve, H; Cornelis, P; Koedam, N

165

Molecular analyses of Pythium irregulare isolates from grapevines in South Africa suggest a single variable species  

Science.gov (United States)

The Pythium irregulare species complex is the most common and widespread Pythium spp. associated with grapevines in South Africa. This species complex can be subdivided into several morphological and phylogenetic species that are all highly similar at the sequence level. The complex includes P. re...

166

Occurrence of mefenoxam resistant isolates of Pythium spp. in the Pacific Northwest  

Science.gov (United States)

Several Pythium spp. can cause leak on potato, and are commonly controlled by mefenoxam, a single-site mode of action fungicide. Previous research has shown that mefenoxam-resistant isolates of Pythium spp. are present in potato production areas of the U.S., but detailed information on occurrence is...

167

Pythium and Fusarium Species Associated with Production of Douglas-Fir Seedlings  

Science.gov (United States)

Methyl bromide has long been used to control Pythium and Fusarium spp. in conifer nurseries in the Pacific Northwest. However, alternative fumigants are now necessary as methyl bromide is an ozone-depleting agent. The efficacy of metam sodium, dimethyl disulfide, and methyl iodide against Pythium ...

168

IMAGE PROCESSING METHOD TO MEASURE SUGARCANE LEAF AREA  

Directory of Open Access Journals (Sweden)

Full Text Available In order to increase the average sugarcane yield per acres with minimum cost farmers are adapting precision farming technique. This paper includes the area measurement of sugarcane leaf based on image processing method which is useful for plants growth monitoring, to analyze fertilizer deficiency and environmental stress,to measure diseases severity. In image processing method leaf area is calculated through pixel number statistic. Unit pixel in the same digital images represent the same size hence from known reference area and pixel count, unit pixel size can calculate, so that it is easy to calculate leaf area by counting total pixel in leaf area region. The results are compared with the results of graphical area measurement method. The experimentally it is proved that image processing method for measuring sugarcane leaf area is accurate and strong practicabilitywith small relative error.

Sanjay B. Patil; Dr. Shrikant K. Bodhe

2011-01-01

169

Pythium burgundicum sp. nov. isolated from soil samples taken in French vineyards.  

UK PubMed Central (United Kingdom)

During the course of investigation on pythiaceous fungi occurring in the Burgundian vineyards, a new species of Pythium has been isolated. This oomycete is characterized by its nonproliferating and nonsporulating, spherical to cylindrical type of sporangia (hyphal bodies) germinating through germ tubes, smooth-walled oogonia that are supplied with hypogynous, monoclinous or rarely diclinous antheridia, and smooth-walled oospores. The antheridial cells are very prominent and are reminiscent of Pythium bifurcatum, Pythium segnitium and Pythium longandrum described previously by the author. The internal transcribed spacer region of the rRNA of this new species is composed of 883 bases, which is quite different from that of the closest relatives. Morphological and molecular features of this new species, named as Pythium burgundicum, are discussed in this article.

Paul B

2009-11-01

170

Sugarcane: A versatile energy source  

International Nuclear Information System (INIS)

Biomass is shown to be viable given the same, economic environment as other energy sources. Sugarcane is shown to be the most economic and versatile biomass feedstock at present. The Brazilian national program has proved that gasoline may be substituted and biomass offers a viable alternative to fossil fuel if rationalization of production, distribution and pricing is implemented. A major step towards feasibility of the sugarcane alternative would be the commercialization of bagasse, preferably as a fuel for generating surplus chemical energy. The efficient use of sugarcane as an energy feedstock offers the possibility of very considerable reductions in (net) greenhouse gas emissions as compared to petroleum derivative fuels.

1992-01-01

171

Sugarcane as a renewable resource  

Energy Technology Data Exchange (ETDEWEB)

Sugarcane (Saccharum officinarum) is grown, generally as a perennial crop, in tropical and subtropical areas; some 750 million tonnes are produced each year. Food, feed and energy are the major products of the sugarcane plant; sugarcane fiber, bagasse, fuels the cane processing plants and provides electricity to local grids through cogeneration. A range of chemicals and polymers is available from process streams and sugars. Microbial products are discussed in the comparison paper on sugarbeet. Chemical transformations reviewed herein include production of sucrose mono-, di- and poly-esters, polyurethanes, carboxylic acid derivatives, and thermally stable polymers. Processes and product will be reviewed.

Clarke, M.A.; Edye, L.A. [Sugar Processing Research Institute, Inc., New Orleans, LA (United States)

1995-12-01

172

Towards the response of water balance to sugarcane expansion in the Rio Grande Basin, Brazil  

Science.gov (United States)

This study explores the short-, medium- and long-term impacts of expansion of the sugarcane plantation on the water balance of the Rio Grande Basin, Brazil, as estimated by changes in evapotranspiration, soil moisture content and surface runoff calculated by a hydrological model. Twenty years of simulation are made using three different land use scenarios that include the basin area planted with sugarcane in 1993, 2000 and 2007 as estimated from satellite images. Complementary, it is used a scenario for sugarcane plantation defined by the Brazilian Institute for Agricultural Research (EMPRAPA) as all areas suitable for sugarcane cultivation within the Rio Grande Basin. In addition, parameters for sugarcane fields were specifically defined via calibration and validation of the hydrological model for all growth phases based on the annual cycle of sugarcane phenology in the Rio Grande Basin. According to results from the land use classification of satellite images, the expansion of sugarcane fields mostly replaced pasture lands. Modelling results for short-, medium- and long-term clarify that impacts of this expansion depended not only on the amount of areas planted with sugarcane, but also the type of land use replaced, location of the expansion within the basin and regional soil properties. Largest impacts on the water balance are observed if areas located close to headwaters with low soil water capacity are planted with sugarcane. In case all areas suitable for sugarcane plantation, as defined by EMBRAPA will actually be planted, simulations showed that the annual accumulated values of evapotranspiration increase up to 180% while surface runoff is reduced to 20% of the values calculated using a land use scenario from 1993.

Pereira, F. F.; Tursunov, M.; Uvo, C. B.

2013-05-01

173

Application of radiation processing to produce biotic elicitor for sugarcane  

International Nuclear Information System (INIS)

Sugarcane is the main raw material for production of sugar and ethanol. In Vietnam, it was reported in 1998 that the area for sugar cane growth was about 257,000 ha. Up to now, the biotic elicitor, oligosaccharide has not been used for sugarcane yet. This study has been carried out to investigate the elicitation and the growth promotion effect of irradiated chitosan (oligochitosan) for sugarcane. The field test results indicated that alpha chitosan (shrimp shell) and beta chitosan (squid pen) samples with the content of water soluble oligomer of about 75% and 70% respectively were the most effective. The disease ratio of sugar cane tree-trunk treated with irradiated chitosan before harvesting time decreased to 30-40% compared to non-treated one. In addition, the productivity of sugarcane increased to about 20%. The combination of metal ion (Zn2+, Cu2+) with oligochitosan did not show the synergic elicitation effect. The results revealed that biotic elicitor made from chitosan by radiation degradation method is very promising for field application not only for protection of disease infection but also for growth promotion of plants. It is believed that this biotic elicitor could be used for safe and sustainable development of agriculture. (author)

2005-01-01

174

Orbital spectral variables, growth analysis and sugarcane yield/ Variáveis espectrais orbitais, indicadoras de desenvolvimento e produtividade da cana-de-açúcar  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese Dados de satélites são tradicionalmente utilizados em monitoramento de culturas. O presente trabalho busca contribuir no entendimento da evolução temporal de indicadores de crescimento da cana-de-açúcar como a biomassa total (BMT), produtividade (TSS), índice de área foliar (LAI) e número de plantas por metro (NPM) por meio de dados orbitais dos satélites Landsat 5 e 7, e verificar o seu potencial para o monitoramento desta. Durante as safras 2000 e 2001, uma á (more) rea comercial em Araras, SP, cultivada com a variedade SP80-1842 no 4º e 5º cortes, foi acompanhada por imagens, buscando-se correlacionar dados espectrais com dados agronômicos. Os dados espectrais foram coletados de duas formas: uma com janelas de quatro pixels e outra com dados médios do talhão (DMt). Regressão linear e múltipla foram usadas para a análise temporal das bandas 3 e 4 e de índices de vegetação. As correlações e ajuste de modelos entre os dados espectrais orbitais e as variáveis agronômicas não apresentaram diferenças estatísticas. Os modelos quadráticos e cúbicos melhor descreveram o desenvolvimento temporal das variáveis espectrais, em função dos dias após o corte e apresentaram significância com os índices de vegetação da razão e por diferença normalizada (NDVI). As correlações entre os dados espectrais médios do talhão e as variáveis agronômicas foram significativas para banda3 e LAI, e entre NDVI e TSS/BMT. Os dados médios do talhão (DMt), para primeira safra (1ªS), para a segunda safra (2ªS) e ambas juntas geraram regressões múltiplas, com coeficientes determinação (r²) variando de 0,68 a 0,97 para a TSS e a BMT, mostrando que os dados espectrais orbitais estudados podem ser empregados no monitoramento da cultura da cana-de-açúcar. Abstract in english Temporal analysis of crop development in commercial fields requires tools for large area monitoring, such as remote sensing. This paper describes the temporal evolution of sugar cane biophysical parameters such as total biomass (BMT), yield (TSS), leaf area index (LAI), and number of plants per linear meter (NPM) correlated to Landsat data. During the 2000 and 2001 cropping seasons, a commercial sugarcane field in Araras, São Paulo state, Brazil, planted with the SP80-18 (more) 42 sugarcane variety in the 4th and 5th cuts, was monitored using nine Landsat images. Spectral data were correlated with agronomic data, obtained simultaneously to the imagery acquisition. Two methodologies were used to collect spectral data from the images: four pixels (2 × 2) window and average of total pixels in the field. Linear and multiple regression analysis was used to study the spectral behavior of the plants and to correlate with agronomic variables (days after harvest-DAC, LAI, NPM, BMT and TSS). No difference was observed between the methodologies to collect spectral data. The best models to describe the spectral crop development in relation to DAC were the quadratic and cubic models. Ratio vegetation index and normalized difference vegetation index demonstrated correlation with DAC, band 3 (B3) was correlated with LAI, and NDVI was well correlated with TSS and BMT. The best fit curves to estimate TSS and BMT presented r² between 0.68 and 0.97, suggesting good potential in using orbital spectral data to monitor sugarcane fields.

Simões, Maurício dos Santos; Rocha, Jansle Vieira; Lamparelli, Rubens Augusto Camargo

2009-08-01

175

Desenvolvimento da cana-de-açúcar cultivar na 56-79 proveniente da propagação de colmos tratados com ethephon/ Growth of sugarcane cultivar na 56-79 originated from stalks treated with ethephon  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese Aplicou-se ethephon nas dosagens de 0,2 e 3 l/ha em cana-de-açúcar NA 56-79, 31 dias antes da colheita. Dos colmos colhidos foram efetuadas avaliações referentes a: infestação da broca da cana; gemas danificadas,entumescidas e brotadas; altura dos colmos; comprimento do ápice; número total de gemas e por último, análises tecnológicas para Pol, Brix, pureza e teor de fibras. Os toletes obtidos desses colmos foram plantados combinando-se as três dosagens de ethe (more) phon com três densidades de plantio: colmos simples, cruzados e duplos. Foram coletados dados semanais e posteriormente mensais de brotação e dados mensais de altura dos colmos. Dados de produção e número de colmos produzidos foram tomados por ocasião do 1º, 2º e 3º cortes da cana-de-açúcar. Os resultados revelaram que a aplicação de ethephon 2 l/ha, no estágio que antecede a colheita, promoveu um aumento do número de gemas e na altura dos colmos, e a dosagem 3 l/ha reduziu o teor de fibras na região apical da cana-de-açúcar em relação ao controle. Observou-se um aumento na velocidade de emergência de gemas obtidas de colmos tratados com o produto na dosagem 2 l/ha, antes do início do perfilhamento. Quanto à densidade de plantio, colmos duplos possibilitaram maior velocidade de emergência, seguidos de colmos cruzados, com relação a colmos simples. O crescimento, perfilhamento e produção de três anos consecutivos da cana-de-açúcar proveniente de toletes obtidos de plantas tratadas com ethephon não diferiram do controle. Notou-se um maior número de colmos produzidos no 1º ano, na densidade de plantio colmos duplos, quando comparados a colmos simples, sem, contudo, haver um aumento correspondente na produção. Abstract in english Ethephon was applied on the dosages 0, 2 e 3 liters per hectare on sugarcane cultivar NA 56-79, 3l days before harvesting. At harvesting time, the following parameters were evaluated: infestation by the Diatraea saccharalis; damaged, swelled and emerged buds; stalks lenght, top lenght; number of buds per stalk and the cane quality. The setts obtained from the stalks were planted at three differents densities: normal, crossed and doubles setts. Initially, the number of spr (more) outs was collected weekly and later monthly. The other parameter, stalk lenght, was obtained under monthly intervals. The stalks number and the production were taken at the 1st, 2nd and 3rd year's growth. The results showed that the ethephon's application on 2 l/ha, before harvesting, increased the number of buds and the stalks lenght. The dosage 3 l/ha reduced the amount of fibers on the apical region of the sugarcane. Increasing of the bud emergency velocity was observed on the dosage 21/ha, before tillering. With reference to planting density, doubles setts showed emergency velocity greater than crossed setts. In turn, the crossed setts proved emergency velocidy greater than normal setts. The growth, tillering and the three years productions of the sugarcane coming from setts of the stalks treated or not with ethephon showed no significative differences.

Melotto, Eunice; Castro, Paulo R.C.; Godoy, Oswaldo P.; Câmara, Gil M.S.; Stupiello, José P.; Iemma, Antonio F.

1987-01-01

176

Produtividade e qualidade tecnológica da soqueira de cana-de-açúcar submetida à aplicação de biorregulador e fertilizantes líquidos/ Productivity and technological quality of sugarcane ratoon subject to the application of plant growth regulator and liquid fertilizers  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese O presente trabalho objetivou avaliar a aplicação de biorreguladores, associados ou não a fertilizantes líquidos, na rebrota e na produtividade da soqueira de cinco genótipos de cana-de-açúcar. O experimento foi desenvolvido no Município de Jaú, São Paulo (SP), num Latossolo Vermelho Eutroférrico. Utilizou-se o delineamento em blocos inteiramente casualizados, em esquema fatorial 5x5, constituído por cinco genótipos (IAC87-3396, IAC91-2218, IAC91-4216, IAC91- (more) 5155 e IACSP93-6006) e cinco tratamentos com biorreguladores, associados ou não a fertilizantes líquidos (Stimulate® a 0,5L ha-1; Stimulate® a 0,5L ha-1 + Starter N® a 3,0L ha-1; Stimulate® a 0,5L ha-1 + Starter N® a 3,0L ha-1 + Cellerate® a 0,5L ha-1; Etefon a 3,0L ha-1 e Testemunha), com quatro repetições. A aplicação dos produtos ocorreu 70 dias após a quarta colheita. Foram avaliados: perfilhamento, produtividade de colmos industrializáveis e de açúcar, fibra, pol % cana e açúcar total recuperável. O etefon proporcionou melhor perfilhamento, mas a resposta foi dependente do genótipo. O maior número de perfilhos promovido pelo etefon não refletiu em maior produtividade. A aplicação de Stimulate® e fertilizantes líquidos não proporcionou efeitos na qualidade da cana-de-açúcar. Houve aumento da produtividade de colmos e de açúcar, independente do genótipo, com o emprego do biorregulador Stimulate®, com ou sem complementação de fertilizante líquido, indicando a possibilidade do aumento da longevidade da cana-de-açúcar. Abstract in english The present work aimed to evaluate the application of plant growth regulators, associate or not to liquid fertilizers, on the ratoon sprouting and productivity of sugarcane genotypes. The experiment was carried out near Jaú city (SP), in a Eutroferric Red Latosol. The experimental design was in randomized complete blocks with factorial treatment structure 5x5, constituted by five genotypes (IAC87-3396, IAC91-2218, IAC91-4216, IAC91-5155 and IACSP93-6006) and five plant g (more) rowth regulators treatments associated or not to liquid fertilizers (Stimulate®, 0,5L ha-1; Stimulate®, 0,5L ha-1, + Starter N®, 3,0L ha-1; Stimulate®, 0,5L ha-1, + Starter N®, 3,0L ha-1, + Cellerate®, 0,5L ha-1; Ethephon, 3,0L ha-1, and control), with four replicates. The application of the products occurred at 70 days after the fourth crop harvest. The attributes tillering, stalk productivity, sugar productivity, fiber, pol % cane and total sugar recoverable were evaluated. Ethephon provided better tillering, but this response was dependent of the genotype. The highest tiller number caused by Ethephon did not mean the highest productivity. The application of Stimulate® and liquid fertilizers did not provide effects on the sugarcane technological quality. There was increase of cane productivity and sugar productivity with the use of plant growth regulator Stimulate® for all genotypes, with or without supplementation of liquid fertilizer, being an indicative for increasing the sugarcane longevity.

Silva, Marcelo de Almeida; Cato, Stella Consorte; Costa, Augusto Guerreiro Fontoura

2010-04-01

177

Converting developing and mature sugarcane carbohydrates into ethanol  

Energy Technology Data Exchange (ETDEWEB)

Experiments were performed employing cane particles obtained from sugarcane at different growth stages until maturation measuring the amount of ethanol produced and the carbohydrate consumption in order to estimate the sugarcane growth stage where both parameters were optimized. Two non-flowering commercial cane varieties NA56 and PR752002 were cultivated and samples taken at different time intervals. Two Saccharomyces cerevisae strains were also compared in the trials. Sucrose was poorly consumed in young cane, which was an unexpected result. Fructose on the other hand was the hexose that remained in the medium at the end of the fermentations specially when using mature sugarcane. There was an increasing trend in ethanol production as a function of days after planting (DAP) as expected; however, a plateau was reached after 225 DAP and the maximum value obtained was between 300 and 325 DAP. When these figures were compared with the corresponding DAP used for sugar production, only 25 days less were needed in the field for maximum ethanol production. On the other hand, it was clear from the data that cane harvesting for ethanol production should not be done after the recommended DAP for commercial sugar production. If this is done, the excess fructose present will not be completely utilized by yeast. Finally, it was observed that the yeast with more affinity for sugarcane fibers showed better ethanol yields in all samples tested. (Copyright copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Rolz, Carlos; De Leon, Roberto [Biochemical Engineering Center, Research Institute, Universidad del Valle de Guatemala (Guatemala)

2010-10-15

178

Evaluation of lectin-expressing transgenic sugarcane against stalkborers (Lepidoptera: Pyralidae): effects on life history parameters.  

UK PubMed Central (United Kingdom)

The impact of snowdrop lectin (Galanthus nivalis agglutinin, GNA) expressed in transgenic sugarcane on life history parameters of Mexican rice borer [Eoreuma loftini (Dyar)] and sugarcane borer [Diatraea saccharalis (F.)] (both Lepidoptera: Pyralidae) was evaluated. In the laboratory, lyophilized sugarcane leaf sheath tissue was incorporated in a meridic diet resulting in a GNA concentration of 0.47% of total protein, and used for insect bioassays over two successive generations. Deleterious effects of GNA were not observed on survival, weight, and developmental periods of larvae and pupae, nor on adult fecundity and egg viability of D. saccharalis. Moreover, in the first generation, addition of transgenic sugarcane tissue to the diet enhanced larval growth in D. saccharalis resulting in higher larval and pupal weight compared with diet with nontransgenic sugarcane, but this effect was not observed in the second generation. In contrast, larval survival, percent adult emergence, and female fecundity of E. loftini were significantly reduced when fed transgenic sugarcane diet compared with nontransgenic sugarcane diet. In addition, a substantial reduction of female pupal weight of E. loftini was observed in the second generation. For both species, the only consistent effect of GNA in both generations was a reduction in adult female longevity. Life table parameters showed that GNA at the level found in the transgenic diet negatively affected development and reproduction of E. loftini, whereas it had a nil to positive effect on development and reproduction of D. saccharalis.

Sétamou M; Bernal JS; Legaspi JC; Mirkov TE; Legaspi BC Jr

2002-04-01

179

Ocorrência de Pythiella vernalis em Pythium aphanidermatum de cultura hidropônica de agrião no Brasil  

Directory of Open Access Journals (Sweden)

Full Text Available Pythiella vernalis foi isolada de Pythium aphanidermatum de cultura hidropônica de agrião, no município de Taubaté, SP, Brasil. É a primeira citação de Pythiella vernalis no Brasil e a primeira referência mundial da espécie em Pythium aphanidermatum.Pythiella vernalis have been isolated from Pythium aphanidermatum on hydroponic culture of Lepidium sativum, in the municipality of Taubaté, São Paulo State, Brazil. It is the first report of the Pythiella vernalis in Brazil and the first world reference of the occurrence of this species in P. aphanidermatum.

Carmen Lidia Amorim Pires-Zottarelli; Amaury da Silva dos Santos; Adauto Ivo Milanez; Matheus Aparecido Pereira Cipriano

2009-01-01

180

Ocorrência de Pythiella vernalis em Pythium aphanidermatum de cultura hidropônica de agrião no Brasil  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese Pythiella vernalis foi isolada de Pythium aphanidermatum de cultura hidropônica de agrião, no município de Taubaté, SP, Brasil. É a primeira citação de Pythiella vernalis no Brasil e a primeira referência mundial da espécie em Pythium aphanidermatum. Abstract in english Pythiella vernalis have been isolated from Pythium aphanidermatum on hydroponic culture of Lepidium sativum, in the municipality of Taubaté, São Paulo State, Brazil. It is the first report of the Pythiella vernalis in Brazil and the first world reference of the occurrence of this species in P. aphanidermatum.

Pires-Zottarelli, Carmen Lidia Amorim; Santos, Amaury da Silva dos; Milanez, Adauto Ivo; Cipriano, Matheus Aparecido Pereira

2009-12-01

 
 
 
 
181

Sugarcane for Bioethanol: Soil and Environmental Issues  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Cultivation of sugarcane for bioethanol is increasing and the area under sugarcane is expanding. Much of the sugar for bioethanol comes from large plantations where it is grown with relatively high inputs. Sugarcane puts a high demands on the soil because of the use of heavy machinery and because la...

Hartemink, A.E.

182

Efficacy of plant extracts and biocontrol agents against Pythium aphanidermatum inciting chilli damping-off  

UK PubMed Central (United Kingdom)

The fungitoxic effects of 66 medicinal plants belonging to different families were evaluated in vitro on Pythium aphanidermatum, the causal agent of chilli damping-off. Of these, Zimmu leaf extract (Allium sativum L. × Allium cepa L.) showed the highest inhibition of mycelial growth of P. aphanidermatum (13.7 mm). The antimicrobial compounds were isolated from Zimmu leaf extract and 22 compounds were identified through gas chromatography mass spectroscopy (GC-MS). Biocontrol agents Trichoderma viride and Pseudomonas fluorescens and Zimmu extract were also tested alone and together in vitro and in vivo experiments for control of P. aphanidermatum. The in vitro studies revealed that combination of T. viride + P. fluorescens + Zimmu leaf extract showed the highest mycelial growth inhibition over the control. Both antagonists were compatible with each other and with Zimmu leaf extract. The pot culture studies revealed that seed treatment with combined application of T. viride + P. fluorescens + Zimmu leaf extract was superior in reducing the pre and post-emergence damping-off incidence (8.3 and 17.0%, respectively), and increased the plant growth and yield (shoot length and root length of 13.7 and 6.3 cm, 146 g/plant, respectively) of chilli when compared to control.

Muthukumar A; Eswaran A; Nakkeeran S; Sangeetha G

2010-12-01

183

Efeitos do glyphosate e sulfometuron-methyl no crescimento e na qualidade tecnológica da cana-de-açúcar/ Effect of glyphosate and sulfometuron-methyl on the growth and technological quality of sugarcane  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese Os herbicidas, mesmo quando usados em doses reduzidas ou utilizados como maturadores, podem alterar a morfofisiologia da planta, o que pode levar a modificações qualitativas e quantitativas na produção. O presente estudo objetivou avaliar a eficiência agronômica e os efeitos, durante o crescimento da cana-soca, da aplicação de glyphosate e sulfometuron-methyl em baixas doses. O delineamento experimental utilizado foi o de blocos casualizados, com quatro repetiçõ (more) es. Os tratamentos foram constituídos pelos herbicidas sulfometuron-methyl e glyphosate em diferentes doses e misturas e por uma testemunha (sem aplicação dos produtos). Uma linha de plantas de cana-de-açúcar foi destinada à aferição da qualidade tecnológica, sendo estabelecido 1 m aleatório a cada época de amostragem. Os colmos coletados foram submetidos ao desponte na altura da gema apical e à desfolha; em seguida, foram encaminhados para processamento segundo a metodologia do Sistema de Pagamento de Cana pelo Teor de Sacarose (SPCTS), sendo considerados os parâmetros tecnológicos: pol cana (PCC), pureza do caldo (PUI), açúcar total recuperável (ATR) e Brix. Nas soqueiras de cana-de-açúcar, realizaram-se análises de crescimento (altura e perfilhos). As avaliações foram realizadas na pré-colheita (30 dias após aplicação dos maturadores) e 30, 60, 90, 120, 150 e 180 dias após a colheita. Os herbicidas glyphosate e sulfometuron-methyl propiciaram melhoria da qualidade tecnológica da matéria-prima,com incrementos significativos na pureza do caldo e no Brix. A aplicação dos produtos não interferiu na produtividade e no teor de açúcar. Houve efeito estimulante no perfilhamento quando se usou glyphosate na dose de 400 mL ha-1 e redução em crescimento (altura) no início do desenvolvimento da cana, porém, com o tempo, o efeito não se manteve. Abstract in english Even when used at low doses, or used as growth regulators, herbicides can change the morphology and physiology of the plant, leading to qualitative and quantitative changes in production. This study aimed to evaluate the agronomic efficiency and the effects during sugarcane ratoon growth after applying low doses of glyphosate and sulfometuron-methyl. The experiment was arranged in a randomized block design with four replications. The treatments consisted of application of (more) two herbicides (glyphosate and sulfometuron-methyl at various doses and mixtures) and a control (without herbicide application). One row of plants was used to measure technological quality, with a random 1 m being established for each sampling time. The stems collected were submitted to apical bud emergence and defoliation and were sent to be processed according to the methodology of the Cane Payment System based on Sucrose Content (CPSSC), considering the following technological parameters: pol cane (PCC), broth purity (BP), total recoverable sugar (TRS), and Brix. The stumps were analyzed for sugarcane growth (height and tillers). Evaluations were performed during pre-harvest (30 DAA), 30, 60, 90, 120, 150 and 180 days after harvest. The treatments with glyphosate and sulfometuron-methyl provided improved technological quality of the raw material, with significant increases in broth purity and Brix. Herbicide application did not affect productivity and sugar content. There was a stimulating effect on tillering with glyphosate at a dose of 400 mL, and growth reduction (height) at the start of cane development, but such effect was not maintained along time.

Meschede, D.K.; Velini, E.D.; Carbonari, C.A.

2010-01-01

184

Pythium insidiosum: morphological and molecular identification of Brazilian isolates Pythium insidiosum: identificação morfológica e molecular de isolados brasileiros  

Directory of Open Access Journals (Sweden)

Full Text Available Pythium insidiosum is an oomycete belonging to the kingdom Stramenipila and it is the etiologic agent of pythiosis. Pythiosis is a life-threatening infectious disease characterized by the development of chronic lesions on cutaneous and subcutaneous, intestinal, and bone tissues in humans and many species of animals. The identification of P. insidiosum is important in order to implement a rapid and definitive diagnosis and an effective treatment. This study reports the identification of 54 isolates of P. insidiosum of horses, dogs and sheep that presented suspicious clinical lesions of pythiosis from different regions in Brazil, by using morphological and molecular assays. Throughout the PCR it was possible to confirm the identity of all Brazilian isolates as being P. insidiosum.Pythium insidiosum é um oomiceto pertencente ao Reino Stramenopila e agente etiológico da pitiose, uma doença infecciosa com riscos de morte. A pitiose é caracterizada pelo desenvolvimento de lesões crônicas sobre os tecidos cutâneos, subcutâneas, intestinal e ósseo em humanos e muitas espécies de animais. A identificação de P. insidiosum é importante, a fim de se obter um diagnóstico rápido e definitivo, bem como um tratamento eficaz. Este estudo relata a identificação de 54 isolados de P. insidiosum de cavalos, cães e ovelhas que apresentavam lesões compatíveis e suspeita clínicas de pitiose, provenientes de diferentes regiões do Brasil, através de métodos morfológicos e moleculares. Através da PCR foi possível confirmar a identidade de todos os isolados brasileiros como sendo P. insidiosum.

Maria Isabel de Azevedo; Daniela I.B. Pereira; Sônia A. Botton; Mateus M. da Costa; Camila D. Mahl; Sydney H. Alves; Janio M. Santurio

2012-01-01

185

Pythium insidiosum: morphological and molecular identification of Brazilian isolates/ Pythium insidiosum: identificação morfológica e molecular de isolados brasileiros  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese Pythium insidiosum é um oomiceto pertencente ao Reino Stramenopila e agente etiológico da pitiose, uma doença infecciosa com riscos de morte. A pitiose é caracterizada pelo desenvolvimento de lesões crônicas sobre os tecidos cutâneos, subcutâneas, intestinal e ósseo em humanos e muitas espécies de animais. A identificação de P. insidiosum é importante, a fim de se obter um diagnóstico rápido e definitivo, bem como um tratamento eficaz. Este estudo relata a (more) identificação de 54 isolados de P. insidiosum de cavalos, cães e ovelhas que apresentavam lesões compatíveis e suspeita clínicas de pitiose, provenientes de diferentes regiões do Brasil, através de métodos morfológicos e moleculares. Através da PCR foi possível confirmar a identidade de todos os isolados brasileiros como sendo P. insidiosum. Abstract in english Pythium insidiosum is an oomycete belonging to the kingdom Stramenipila and it is the etiologic agent of pythiosis. Pythiosis is a life-threatening infectious disease characterized by the development of chronic lesions on cutaneous and subcutaneous, intestinal, and bone tissues in humans and many species of animals. The identification of P. insidiosum is important in order to implement a rapid and definitive diagnosis and an effective treatment. This study reports the ide (more) ntification of 54 isolates of P. insidiosum of horses, dogs and sheep that presented suspicious clinical lesions of pythiosis from different regions in Brazil, by using morphological and molecular assays. Throughout the PCR it was possible to confirm the identity of all Brazilian isolates as being P. insidiosum.

Azevedo, Maria Isabel de; Pereira, Daniela I.B.; Botton, Sônia A.; Costa, Mateus M. da; Mahl, Camila D.; Alves, Sydney H.; Santurio, Janio M.

2012-07-01

186

The Brazilian sugarcane innovation system  

International Nuclear Information System (INIS)

Ethanol has recently been of great interest worldwide because it is a viable economic alternative to petroleum products and it is a renewable source of energy that mitigates the emission of greenhouse gases. Brazilian bioethanol from sugarcane is the most successful case at the world level because of its low cost and low level of greenhouse gas emissions. Brazil's success with sugarcane cannot be understood as based solely on a natural comparative advantage, but as a result of efforts that culminated in a positive trajectory of technological learning, relying mostly on incremental innovations. The purpose of this article is to analyze the key aspects of the innovation system built around the Brazilian sugarcane industry. It is based on the national innovation systems approach according to which innovation results from the interaction of different institutional actors. Institutional arrangements are analyzed as the basis for the innovative process, in particular R and D and the innovation policies and strategies of the main players in the sugarcane sector, including sugar and ethanol mills, industrial goods suppliers, public and private research institutions, and governmental agencies. - Research Highlights: ? The Brazilian success in bioethanol is due to the sugarcane innovation system. ? Private funds for R and D became central after IAA closure. ? Nowadays Brazilian innovation system is transforming to keep its leadership. ? Public funds for research in the second generation bioethanol.

2011-01-01

187

The Brazilian sugarcane innovation system  

Energy Technology Data Exchange (ETDEWEB)

Ethanol has recently been of great interest worldwide because it is a viable economic alternative to petroleum products and it is a renewable source of energy that mitigates the emission of greenhouse gases. Brazilian bioethanol from sugarcane is the most successful case at the world level because of its low cost and low level of greenhouse gas emissions. Brazil's success with sugarcane cannot be understood as based solely on a natural comparative advantage, but as a result of efforts that culminated in a positive trajectory of technological learning, relying mostly on incremental innovations. The purpose of this article is to analyze the key aspects of the innovation system built around the Brazilian sugarcane industry. It is based on the national innovation systems approach according to which innovation results from the interaction of different institutional actors. Institutional arrangements are analyzed as the basis for the innovative process, in particular R and D and the innovation policies and strategies of the main players in the sugarcane sector, including sugar and ethanol mills, industrial goods suppliers, public and private research institutions, and governmental agencies. - Research Highlights: {yields} The Brazilian success in bioethanol is due to the sugarcane innovation system. {yields} Private funds for R and D became central after IAA closure. {yields} Nowadays Brazilian innovation system is transforming to keep its leadership. {yields} Public funds for research in the second generation bioethanol.

Tosi Furtado, Andre, E-mail: furtado@ige.unicamp.b [Department of Science and Technology Policy-DPCT, Institute of Geosciences, University of Campinas, UNICAMP (Brazil); Gaya Scandiffio, Mirna Ivonne, E-mail: mirnags31@globo.co [Bioethanol Science and Technology Center-CTBE, Campinas, SP (Brazil); Barbosa Cortez, Luis Augusto, E-mail: cortez@agr.com.b [School of Agriculture (FEAGRI), University of Campinas, UNICAMP (Brazil)

2011-01-15

188

Biochemical and biophysical characterization of sugarcane proteins involved in thermal stress  

Energy Technology Data Exchange (ETDEWEB)

Sugarcane has gained worldwide interest due to its potential to produce ethanol as an alternative energy source. 2 Therefore, it is of general interest to study the physiological and biochemical aspects of sugarcane, especially those involved in stress tolerance, which may be important to understand survival during exposure to high temperatures. In plants, sHsps rank among the most important heat shock proteins expressed during heat stress. They can accumulate up to 1% in leaves and are correlated with the acquisition of thermotolerance. In this context, the study of sHsps proteins may lead to strategies for increasing sugarcane survival and fitness, allowing for its growth in regions where sugarcane has not been produced before. (author)

Tiroli-Cepeda, Ana Olivia [Laboratorio Nacional de Luz Sincrotron (LNLS), Campinas, SP (Brazil); Ramos, Carlos Henrique Inacio [Universidade Estadual de Campinas (UNICAMP), Campinas, SP (Brazil). Inst. de Quimica

2006-07-01

189

Biochemical and biophysical characterization of sugarcane proteins involved in thermal stress  

International Nuclear Information System (INIS)

Sugarcane has gained worldwide interest due to its potential to produce ethanol as an alternative energy source. 2 Therefore, it is of general interest to study the physiological and biochemical aspects of sugarcane, especially those involved in stress tolerance, which may be important to understand survival during exposure to high temperatures. In plants, sHsps rank among the most important heat shock proteins expressed during heat stress. They can accumulate up to 1% in leaves and are correlated with the acquisition of thermotolerance. In this context, the study of sHsps proteins may lead to strategies for increasing sugarcane survival and fitness, allowing for its growth in regions where sugarcane has not been produced before. (author)

2006-01-01

190

Characterisation of Pythium paroecandrum and its antagonism towards Botrytis cinerea, the causative agent of grey mould disease of grape.  

UK PubMed Central (United Kingdom)

Pythium paroecandrum (B-30), an oomycete, was isolated from soil samples taken from a wheat field in Genlis in the Burgundy region of France and was found to check the growth and development of Botrytis cinerea, a serious grapevine pathogen. The oomycete is a fast-growing organism, living on vegetable debris, and can be recognised by its catenulate hyphal swellings, catenulate oogonia, and monoclinous antheridia. When grown together with B. cinerea, the causal agent of the grey mould disease of the grapevine, P. paroecandrum shows a pronounced antagonism and suppresses its growth and its aptitude to provoke the grey mould symptoms. Morphological features of this oomycete, its antagonism to B. cinerea, the sequences of the internal transcribed spacer region of its nuclear ribosomal DNA, and its comparison with related species are discussed in this article.

Abdelghani el Y; Bala K; Paul B

2004-01-01

191

Use of dry-milling derived thin stillage for producing eicosapentaenoic acid (EPA) by the fungus Pythium irregulare.  

Science.gov (United States)

This study was to explore the use of thin stillage, a major byproduct in dry milling corn-ethanol plants, for production of eicosapentaenoic acid (EPA) by the fungus Pythium irregulare. Thin stillage contains various compounds that were ideal for fungal growth. Thin stillage concentration and temperature played important roles in fungal growth and EPA production. When 50% thin stillage was used in a stepwise temperature shift culture process, the cell density reached 23 g/L at day 9 with EPA yield and productivity of 243 and 27 mg/L day, respectively. The fungal biomass contained 39% lipid, 28% protein, 30% carbohydrate, and 3% ash. The fungal culture also generated a nutrient-depleted liquid by removing organic compounds in the raw thin stillage. The results collectively showed a new use of thin stillage by feeding to the fungus P. irregulare for producing omega-3 fatty acids. PMID:22386467

Liang, Yi; Zhao, Xuefei; Strait, Megan; Wen, Zhiyou

2012-02-16

192

Use of dry-milling derived thin stillage for producing eicosapentaenoic acid (EPA) by the fungus Pythium irregulare.  

UK PubMed Central (United Kingdom)

This study was to explore the use of thin stillage, a major byproduct in dry milling corn-ethanol plants, for production of eicosapentaenoic acid (EPA) by the fungus Pythium irregulare. Thin stillage contains various compounds that were ideal for fungal growth. Thin stillage concentration and temperature played important roles in fungal growth and EPA production. When 50% thin stillage was used in a stepwise temperature shift culture process, the cell density reached 23 g/L at day 9 with EPA yield and productivity of 243 and 27 mg/L day, respectively. The fungal biomass contained 39% lipid, 28% protein, 30% carbohydrate, and 3% ash. The fungal culture also generated a nutrient-depleted liquid by removing organic compounds in the raw thin stillage. The results collectively showed a new use of thin stillage by feeding to the fungus P. irregulare for producing omega-3 fatty acids.

Liang Y; Zhao X; Strait M; Wen Z

2012-05-01

193

In Vitro Activity of Terbinafine Combined with Caspofungin and Azoles against Pythium insidiosum?  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this text we evaluated the in vitro antifungal activities of terbinafine combined with caspofungin, miconazole, ketoconazole, and fluconazole against 17 Pythium insidiosum strains by using the microdilution checkerboard method. Synergistic interactions were observed with terbinafine combined with...

Cavalheiro, Ayrton S.; Maboni, Grazieli; de Azevedo, Maria I.; Argenta, Juliana S.; Pereira, Daniela I. B.; Spader, Tatiana B.

194

Pathogenicity of Pythium aphanidermatum to Chrysanthemum in Combined Inoculations with Belonolaimus longicaudatus or Meloidogyne incognita  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Rooted cuttings of 'Iceberg' chrysanthemum in steamed soil were inoculated with the nematodes Belonolaimus longicaudatus, and Meloidogyne incognita, alone and combined with Pythium aphanidermatum, a fungus pathogen of chrysanthemum. B. longicaudatus alone severely restricted the root system; with P....

Johnson, A. W.; Littrell, R. H.

195

Snow mould caused by a Pythium sp.: a potential vascular plant pathogen in the maritime Antarctic  

UK PubMed Central (United Kingdom)

The pathogenicity of an isolate of a Pythium species from Signy Island in the South Orkney Islands was tested against the Antarctic hairgrass Deschampsia antarctica. The isolate was found to infect plants at 8[ordinal indicator, masculine]C and to cause foliar and root symptoms similar to those seen in other Pythium infections in grasses. Analysis of ribosomal RNA sequences placed it, together with another isolate from Antarctica, in a clade that included the known snow moulds caused by Pythium spp. Sporangia and oogonia were produced in culture, but the isolate differed from other Pythium spp. in producing chlamydospores in older cultures and plant tissue. This is the first report of a pathogen of an eukaryotic vascular plant in the maritime Antarctic region.

Bridge PD; Newsham KK; Denton GJ

2008-12-01

196

Larval Bradysia impatiens (Diptera: Sciaridae) potential for vectoring Pythium root rot pathogens.  

Science.gov (United States)

A series of laboratory experiments were conducted to investigate the capacity of Bradysia impatiens (Johannsen) larvae to ingest propagules from two strains each of Pythium aphanidermatum (Edson) Fitzp. and P. ultimum Trow and transmit the pathogens to healthy geranium seedlings on a filter-paper substrate in petri dishes. The capacity of fungus gnat larvae to transmit P. aphanidermatum to seedlings rooted in a commercial peat-based potting mix and germination of Pythium oospores and hyphal swellings before and after passage through the guts of larval fungus gnats were also examined. Assays revealed that Pythium spp. transmission by larval fungus gnats varied greatly with the assay substrate and also with the number and nature of ingested propagules. Transmission was highest (65%) in the petri dish assays testing larvae fed P. aphanidermatum K-13, a strain that produced abundant oospores. Transmission of strain K-13 was much lower (Pythium spp. PMID:22085299

Braun, S E; Sanderson, J P; Wraight, S P

2012-03-01

197

The Involvement of Cellulase and Laminaranase in the Formation of Pythium Protoplasts.  

Science.gov (United States)

Five inducible streptomycete lytic enzyme complexes were equally capable of producing protoplasts from a Pythium sp. strain PRL 2142, when compared on a quantitative basis. Both cellulase and laminaranase from various microbial sources were required to pr...

D. E. Eveleigh J. H. Sietsma R. H. Haskins

1967-01-01

198

Mature-stem expression of a silencing-resistant sucrose isomerase gene drives isomaltulose accumulation to high levels in sugarcane.  

UK PubMed Central (United Kingdom)

Isomaltulose (IM) is a natural isomer of sucrose. It is widely approved as a food with properties including slower digestion, lower glycaemic index and low cariogenicity, which can benefit consumers. Availability is currently limited by the cost of fermentative conversion from sucrose. Transgenic sugarcane plants with developmentally-controlled expression of a silencing-resistant gene encoding a vacuole-targeted IM synthase were tested under field conditions typical of commercial sugarcane cultivation. High yields of IM were obtained, up to 483 mm or 81% of total sugars in whole-cane juice from plants aged 13 months. Using promoters from sugarcane to drive expression preferentially in the sugarcane stem, IM levels were consistent between stalks and stools within a transgenic line and across consecutive vegetative field generations of tested high-isomer lines. Germination and early growth of plants from setts were unaffected by IM accumulation, up to the tested level around 500 mm in flanking stem internodes. These are the highest yields ever achieved of value-added materials through plant metabolic engineering. The sugarcane stem promoters are promising for strategies to achieve even higher IM levels and for other applications in sugarcane molecular improvement. Silencing-resistant transgenes are critical to deliver the potential of these promoters in practical sugarcane improvement. At the IM levels now achieved in field-grown sugarcane, direct production of IM in plants is feasible at a cost approaching that of sucrose, which should make the benefits of IM affordable on a much wider scale.

Mudge SR; Basnayake SW; Moyle RL; Osabe K; Graham MW; Morgan TE; Birch RG

2013-05-01

199

Mature-stem expression of a silencing-resistant sucrose isomerase gene drives isomaltulose accumulation to high levels in sugarcane.  

Science.gov (United States)

Isomaltulose (IM) is a natural isomer of sucrose. It is widely approved as a food with properties including slower digestion, lower glycaemic index and low cariogenicity, which can benefit consumers. Availability is currently limited by the cost of fermentative conversion from sucrose. Transgenic sugarcane plants with developmentally-controlled expression of a silencing-resistant gene encoding a vacuole-targeted IM synthase were tested under field conditions typical of commercial sugarcane cultivation. High yields of IM were obtained, up to 483 mm or 81% of total sugars in whole-cane juice from plants aged 13 months. Using promoters from sugarcane to drive expression preferentially in the sugarcane stem, IM levels were consistent between stalks and stools within a transgenic line and across consecutive vegetative field generations of tested high-isomer lines. Germination and early growth of plants from setts were unaffected by IM accumulation, up to the tested level around 500 mm in flanking stem internodes. These are the highest yields ever achieved of value-added materials through plant metabolic engineering. The sugarcane stem promoters are promising for strategies to achieve even higher IM levels and for other applications in sugarcane molecular improvement. Silencing-resistant transgenes are critical to deliver the potential of these promoters in practical sugarcane improvement. At the IM levels now achieved in field-grown sugarcane, direct production of IM in plants is feasible at a cost approaching that of sucrose, which should make the benefits of IM affordable on a much wider scale. PMID:23297683

Mudge, Stephen R; Basnayake, Shiromi W V; Moyle, Richard L; Osabe, Kenji; Graham, Michael W; Morgan, Terence E; Birch, Robert G

2013-01-09

200

Crecimiento y dinámica de acumulación de nutrientes en caña de azúcar: II. micronutrientes/ Growth and dynamics of nutrient accumulation in sugarcane: I. Micronutrients  

Scientific Electronic Library Online (English)

Full Text Available Abstract in spanish Con la finalidad de determinar la dinámica de acumulación y distribución de micronutrientes en el cultivo de caña de azúcar variedad RB 85-5035, se condujo un estudio en Fundacaña, ubicada en la localidad de Chivacoa, estado Yaracuy, Venezuela. Se realizaron 10 muestreos de la parte aérea de la planta a través del ciclo de crecimiento. Cada muestra constó de tres cepas, tomadas al azar con una frecuencia mensual, en una superficie de 0,6 m²/cepa, a las cuales se (more) les determinó la concentración de Fe, Cu, Zn, Mn, B y Mo en tallos y hojas. Las muestras de tejido fueron analizadas por los laboratorios Land Crop en York, Inglaterra. Se determinó que los períodos críticos de absorción de micronutrientes se ubican en la fase vegetativa y en la etapa de maduración del cultivo. Los micronutrientes Fe, Mn, B y Mo se almacenaron en mayor cantidad en el tejido foliar de la planta, mientras que Cu y Zn se acumularon de forma más pronunciada en los tallos a lo largo del ciclo. Los patrones de acumulación mostraron que los requerimientos de micronutrientes fueron: Fe=5241,5 g·ha-1, Cu=121,1 g·ha-1, Zn=875,6 g·ha-1, Mn=1142,4 g·ha-1, B=116,4 g·ha-1 y Mo=33,4 g·ha-1. Abstract in english With the purpose of determining the dynamics of micronutrient accumulation and partitioning of sugarcane var. RB 85-5035, a trial was conducted in Fundacaña, located in Chivacoa, Yaracuy State, Venezuela. Ten samples of the aerial part of the plant were taken through the growing season, and each sample consisted of three stumps, taken at random on a monthly basis in an area of 0.6 m²·cepa-1. Concentrations of Fe, Cu, Zn, Mn, B and Mo on stems and leaves were analyzed b (more) y Land Crop Laboratories in York, England. It was determined that the critical periods for micronutrient absorption are found in the vegetative phase and crop ripening. The micronutrients Fe, Mn, B and Mo were stored in greater amounts in the leaf tissue of the plant, while Cu and Zn accumulated more pronounced in the stems during the cycle. The accumulation patterns showed that the crop micronutrient requirements were: Fe=5241.5 g·ha-1, Cu=121.1 g·ha-1, Zn=875.6 g·ha-1, Mn=1142.4 g·ha-1, B=116.4 g·ha-1 and Mo=33.4 g·ha-1.

Rengel, Marcos; Gil, Fernando; Montaño, José

2011-08-01

 
 
 
 
201

Pelleting of seed with the antagonist Pythium oligandrum for biological control of damping-off.  

UK PubMed Central (United Kingdom)

Pythium oligandrum oospores, incorporated in clay carrier, survived a commercial seed-pelleting process to give protection against damping-off in sugar beet and cress induced by Pythium ultimum, together with damping-off in carrot caused by Mycocentrospora acerina. It is suggested that field scale evaluation of P. oligandrum as a biocontrol of fungally incited seedling diseases is now both feasible and desirable.

Lutchmeah RS; Cooke RC

1985-12-01

202

First Report of Collar and Root Rot Caused by Pythium ultimum on Coriander in Italy  

UK PubMed Central (United Kingdom)

Coriander, Coriandrum sativum L., is an annual herb in the family Apiaceae. This plant, native to southern Europe, northern Africa, and southeastern Asia, is used in cooking as well as for medicinal uses. The leaves are commonly referred to as cilantro. In October 2009, severe outbreaks of a previously unknown root rot were observed in a commercial field located in the Alessandria Province (northern Italy) on 20-day-old plants belonging to cv. Comune. Five percent of plants were affected, showing stunting and extensive chlorosis starting on external leaves that eventually wilted. Root systems and collars of diseased plants appeared rotted. In advanced stages, young leaves were affected and the plants eventually collapsed and tissues dried out. Tissue fragments of 1 mm2 were excised from the roots of infected plants, dipped in a solution containing 1% sodium hypochlorite, and plated on potato dextrose agar (PDA) and a medium selective for Oomycetes (3). Plates were incubated under constant fluorescent light at 22 ± 1°C for 4 to 5 days. One isolate, grown on V8 medium (vegetable mix, 300 g; agar, 15 g; CaCO3, 1.5g; and distilled water, 1 liter), and observed under a light microscope showed hyphae generally aseptate, ranging from 1.3 to 6.24 ?m in diameter, and produced sporangia consisting of complexes of swollen hyphal branches. Oogonia were globose, smooth, and 20.3 to 33.4 (average 25.4) ?m in diameter. Antheridia were monoclinous, extending from immediately below oogonium, and measured 10.8 to 17.8 × 7.6 to 12.7 (average 14.4 × 10.4) ?m. Oospores were single, globose, aplerotic and thick walled, and 15.8 to 24.2 (average 17.8) ?m in diameter. These morphological characters were used to identify the microorganism as a Pythium sp. (3). The internal transcribed spacer (ITS) region of rDNA of a single isolate was amplified using the primers ITS1/ITS4 (2,4) and sequenced. BLAST analysis (1) of the 874-bp segment showed a 100% homology with the sequence of Pythium ultimum. The nucleotide sequence has been assigned the GenBank Accession No. GU478314. Pathogenicity tests were performed twice on coriander cv. Comune. Plants were grown in 2-liter pots containing a Brill Type 5 substrate (Brill Substrate GmbH & Co. KG, Niedersachsen, Germany) consisting of 15% blond peat, 85% black peat, pH 5.5 to 6, and pasteurized at 80°C for 30 min. The potting mix was infested at a rate of 5 g/liter with wheat and hemp kernels colonized with one strain of P. ultimum. Ten plants (1 plant per pot) were grown in the infested substrate and 10 plants were grown in noninfested substrate. Plants were kept in a growth chamber at 20°C. The first symptoms, consisting of reduced growth and chlorosis, developed within 7 days, while control plants remained healthy. P. ultimum was consistently isolated from the roots. To our knowledge, this is the first report of P. ultimum causing disease of coriander in Italy as well as worldwide. At this time, the economic importance of Pythium rot on coriander in Italy remains unknown.

Garibaldi A; Gilardi G; Gullino ML

2010-09-01

203

Pythium species in 13 various types of water bodies of N-E Poland  

Directory of Open Access Journals (Sweden)

Full Text Available Pythium species and environmental factors in various types of water bodies (2 springs, 2 rivers, 3 ponds and 6 different trophic lakes) were studied. Samples of water were collected every two months (springs, rivers, ponds) and every three months (lakes) in the years 1996-1999 for hydrochemical analysis and in order to determine the Pythium species content. From springs rivers and ponds collected were also ice blocks for determinations of presence of Pythium species. Buckwheatand hemp-seeds, cellophane and snake exuviae were used as bait. Forty-five species of Pythium were found in various types of water bodies. Pythium acanthicum, P. complectens, P. complens, P. diameson, P. dissimile, P. elongatum, P. lucens, P. megalacanthum, P. nagae, P. oedochilum, P. oryzae, P. palingenes, P. periilum and P. polysporum were recorded for the first time in Poland. The largest mean number of species was observed in spring Cypisek, a bit fewer in spring Jaroszówka and lake Bia?e (oligotrophic-like waters). The lowest mean number of Pythium species was noted in pond Akcent and Pa?acowy (polytrophic waters). In all types of water bodies the higest mean number of species was found in winter, and the lowest in summer.

Bazyli Czeczuga; Anna Snarska

2001-01-01

204

Molecular variability in Pythium aphanidermatum causing rhizome rot of ginger  

Directory of Open Access Journals (Sweden)

Full Text Available In isozymatic analysis, i.e., peroxidase, polyphenoloxidase and catalase, polymorphic banding pattern was observed in some isolates of Pythium aphanidermatum indicating variation in the pathogen. Molecular variability among 12 isolates of the pathogen was studied by using PCR based RAPD method. RAPD analysis of using 40 random primers, resulted in 313 amplicon levels, out of which 245 polymorphic bands levels were observed. The cumulative analysis of similarity values placed 12 isolates in 2 clusters. The results showed the possibility of using RAPD technique to distinguish variability among the isolates of P. aphanidermatum. This information could then be used to determine specific primers that would allow the identification of the fungus directly from plant material or in the soil.

SHALINI D. SAGAR, SRIKANT KULKARNI and YASHODA R. HEGDE

2011-01-01

205

Multitemporal Observations of Sugarcane by TerraSAR-X Images  

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Full Text Available The objective of this study is to investigate the potential of TerraSAR-X (X-band) in monitoring sugarcane growth on Reunion Island (located in the Indian Ocean). Multi-temporal TerraSAR data acquired at various incidence angles (17°, 31°, 37°, 47°, 58°) and polarizations (HH, HV, VV) were analyzed in order to study the behaviour of SAR (synthetic aperture radar) signal as a function of sugarcane height and NDVI (Normalized Difference Vegetation Index). The potential of TerraSAR for mapping the sugarcane harvest was also studied. Radar signal increased quickly with crop height until a threshold height, which depended on polarization and incidence angle. Beyond this threshold, the signal increased only slightly, remained constant, or even decreased. The threshold height is slightly higher with cross polarization and higher incidence angles (47° in comparison with 17° and 31°). Results also showed that the co-polarizations channels (HH and VV) were well correlated. High correlation between SAR signal and NDVI calculated from SPOT-4/5 images was observed. TerraSAR data showed that after strong rains the soil contribution to the backscattering of sugarcane fields can be important for canes with heights of terminal visible dewlap (htvd) less than 50 cm (total cane heights around 155 cm). This increase in radar signal after strong rains could involve an ambiguity between young and mature canes. Indeed, the radar signal on TerraSAR images acquired in wet soil conditions could be of the same order for fields recently harvested and mature sugarcane fields, making difficult the detection of cuts. Finally, TerraSAR data at high spatial resolution were shown to be useful for monitoring sugarcane harvest when the fields are of small size or when the cut is spread out in time. The comparison between incidence angles of 17°, 37° and 58° shows that 37° is more suitable to monitor the sugarcane harvest. The cut is easily detectable on TerraSAR images for data acquired less than two or three months after the cut. The radar signal decreases about 5dB for images acquired some days after the cut and 3 dB for data acquired two month after the cut (VV-37°). The difference in radar signal becomes negligible (

Nicolas Baghdadi; Rémi Cresson; Pierre Todoroff; Soizic Moinet

2010-01-01

206

Fed-batch cultivation of Cellulomonas on sugarcane bagasse pith  

Energy Technology Data Exchange (ETDEWEB)

A high biomass concentration (19.9 g/L) was obtained with the fed-batch cultivation of Cellulomonas on pretreated sugarcane bagasse pith. Similar results in biomass concentration, yield, and substrate consumption were obtained with the discontinuous feed of bagasse as with discontinuous feed supplemented with a partial continuous addition of salts. Two or more growth phases were detected, probably caused by the differential utilization of bagasse components. An acceptably low content of bagasse components remained in the biomass after separation.

Rodriguez, H.; Enriquez, A.

1985-02-01

207

Isolation of Aspergillus sulphureus, Penicillium islandicum and Paecilomyces variotii from Agricultural Soil and their Biological Activity Against Pythium spinosum, the Damping-Off Organism of Soybean  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This research was undertaken to study the biological control of Pythium spinosum var. spinosum, the damping-off organism of soybean using three selected soil fungi of Aspergillus sulphureus, Penicillium islandicum and Paecilomyces variotii. Pythium spinosum var.

Hashem Al-Sheikh; H.M.A. Abdelzaher

208

Development and yield of sugarcane after application of plant growth regulators in the midle of crop season/ Desenvolvimento e produtividade da cana-de-açúcar após aplicação de reguladores vegetais em meio de safra  

Directory of Open Access Journals (Sweden)

Full Text Available The supply of technological quality raw material for providing economical return is the most important necessity of sugar and alcohol industry. The objective of this work was to evaluate the development and productivity of sugarcane stalks due to plant regulators application at half crop. The experiment was carried out in a randomized block design with five replications. The treatments consisted of four plant regulators of the class of the growth retainers (Ethephon, Ehyl-trinexapac, Potassium nitrate, Potassium nitrate + Boron) application and a control (natural ripening). Ethyl-trinexapac and Ethephon treatments were efficient to hold up growth process regarding height of plants, but had no effect on diameter of stalks. The maintenance of bud top integrity made possible the increase in diameter of stalks, without interrupting the growth process regarding height of plants. According to application time the ripeners provided improvement on technological quality of raw material. The ripeners did not affect the number of plants per meter at harvest and did not cause alterations int the amount mass of stalks per hectare. The ripeners did not affect the regrowth of the ratoon cane. O fornecimento de matéria-prima de qualidade tecnológica que garanta retorno econômico é uma das maiores necessidades da indústria sucroalcooleira. O objetivo do trabalho foi avaliar o desenvolvimento e a produtividade de colmos de cana-de-açúcar decorrente da aplicação de reguladores vegetais no meio da safra. O delineamento experimental utilizado foi o de blocos casualizados, com cinco repetições. Foram utilizados cinco tratamentos constituídos pela aplicação dos reguladores vegetais da classe dos retardantes de crescimento etefon e etil-trinexapac, e de KNO3 e KNO3 + Boro e uma testemunha (maturação natural). O etil-trinexapac e o etefon atuaram de forma eficiente em retardar o processo de crescimento em altura das plantas de cana-de-açúcar, sem ocasionar alterações no diâmetro dos colmos. A manutenção da integridade da gema apical possibilitou o incremento no diâmetro dos colmos sem interromper o crescimento em altura das plantas. Os maturadores propiciaram, conforme a época de aplicação, melhoria na qualidade tecnológica da matéria-prima. Ainda, não afetaram o número de colmos na colheita, não produziram alterações quantitativas na massa de colmos por hectare, e não afetaram a rebrora da soqueira da cana-de-açúcar.

Glauber Henrique Pereira Leite; Carlos Alexandre Costa Crusciol; Marcelo de Almeida Silva

2011-01-01

209

Sugarcane Variety Census: Florida 2008  

Science.gov (United States)

The Florida sugarcane industry produces about 25% of all sugar produced in the U.S. Varieties originate from two sources, a private breeding and selection program of the United States Sugar Corporation in Clewiston, Florida and a public program at Canal Point, Florida supported by the USDA-Agricultu...

210

The Brazilian sugarcane innovation system  

Energy Technology Data Exchange (ETDEWEB)

Ethanol has recently been of great interest worldwide because it is a viable economic alternative to petroleum products and it is a renewable source of energy that mitigates the emission of greenhouse gases. Brazilian bioethanol from sugarcane is the most successful case at the world level because of its low cost and low level of greenhouse gas emissions. Brazil's success with sugarcane cannot be understood as based solely on a natural comparative advantage, but as a result of efforts that culminated in a positive trajectory of technological learning, relying mostly on incremental innovations. The purpose of this article is to analyze the key aspects of the innovation system built around the Brazilian sugarcane industry. It is based on the national innovation systems approach according to which innovation results from the interaction of different institutional actors. Institutional arrangements are analyzed as the basis for the innovative process, in particular R and D and the innovation policies and strategies of the main players in the sugarcane sector, including sugar and ethanol mills, industrial goods suppliers, public and private research institutions, and governmental agencies. (author)

Furtado, Andre Tosi [Department of Science and Technology Policy - DPCT, Institute of Geosciences, University of Campinas, UNICAMP (Brazil); Scandiffio, Mirna Ivonne Gaya [Bioethanol Science and Technology Center - CTBE, Campinas, SP (Brazil); Cortez, Luis Augusto Barbosa [School of Agriculture (FEAGRI), University of Campinas, UNICAMP (Brazil)

2011-01-15

211

Influence of temperature on Pythium splendens--induced root disease on carambola, Averrhoa carambola.  

UK PubMed Central (United Kingdom)

A series of glasshouse and incubator studies were conducted to investigate the role played by Pythium splendens in a decline disorder of carambola, Averrhoa carambola. Plants, 4-6 months old, were grown in native calcareous soil either infested or not infested with the pathogen. Isolates recovered from atemoya, carambola and passion fruit grew optimally at 30 degrees C, and significantly (P < 0.05) increased root necrosis and reduced root, shoot and total biomass of carambola. Temperature had a profound impact on the latter relationships. Two or more times more necrosis developed at 10 and 15 degrees C than at 25 and 30 degrees C. Total biomass accumulations were over four times greater at 30 degrees C than at 10 degrees C, and were always lower in soil infested with P. splendens. When biomass totals from infested and noninfested soil were compared, relative values were lowest at 15 and 20 degrees C and were almost two times greater at 30 degrees C than at 20 degrees C. Root infection by P. splendens was greatest at 15 and 20 degrees C, far below the species' optimum for growth, and at 30 degrees C was over nine times lower than at 15 and 20 degrees C. This is the first detailed report of P. splendens as a pathogen of carambola.

Ploetz RC

2004-02-01

212

Influence of temperature on Pythium splendens--induced root disease on carambola, Averrhoa carambola.  

Science.gov (United States)

A series of glasshouse and incubator studies were conducted to investigate the role played by Pythium splendens in a decline disorder of carambola, Averrhoa carambola. Plants, 4-6 months old, were grown in native calcareous soil either infested or not infested with the pathogen. Isolates recovered from atemoya, carambola and passion fruit grew optimally at 30 degrees C, and significantly (P < 0.05) increased root necrosis and reduced root, shoot and total biomass of carambola. Temperature had a profound impact on the latter relationships. Two or more times more necrosis developed at 10 and 15 degrees C than at 25 and 30 degrees C. Total biomass accumulations were over four times greater at 30 degrees C than at 10 degrees C, and were always lower in soil infested with P. splendens. When biomass totals from infested and noninfested soil were compared, relative values were lowest at 15 and 20 degrees C and were almost two times greater at 30 degrees C than at 20 degrees C. Root infection by P. splendens was greatest at 15 and 20 degrees C, far below the species' optimum for growth, and at 30 degrees C was over nine times lower than at 15 and 20 degrees C. This is the first detailed report of P. splendens as a pathogen of carambola. PMID:15119860

Ploetz, Randy C

2004-02-01

213

Biological control of plant pathogens: advantages and limitations seen through the case study of Pythium oligandrum.  

Science.gov (United States)

The management of certain plant beneficial microorganisms [biological control agents (BCAs)] seems to be a promising and environmental friendly method to control plant pathogens. However, applications are still limited because of the lack of consistency of BCAs when they are applied in the field. In the present paper, the advantages and limitations of BCAs are seen through the example of Pythium oligandrum, an oomycete that has received much attention in the last decade. The biological control exerted by P. oligandrum is the result of a complex process, which includes direct effects through the control of pathogens and/or indirect effects mediated by P. oligandrum, i.e. induction of resistance and growth promotion. P. oligandrum antagonism is a multifaceted and target fungus-dependent process. Interestingly, it does not seem to disrupt microflora biodiversity on the roots. P. oligandrum has an atypical relationship with the plant because it rapidly penetrates into the root tissues but it cannot stay alive in planta. After root colonisation, because of the elicitation by P. oligandrum of the plant-defence system, plants are protected from a range of pathogens. The management of BCAs, here P. oligandrum, is discussed with regard to its interactions with the incredibly complex agrosystems. PMID:23695856

Gerbore, J; Benhamou, N; Vallance, J; Le Floch, G; Grizard, D; Regnault-Roger, C; Rey, P

2013-05-22

214

Biological control of plant pathogens: advantages and limitations seen through the case study of Pythium oligandrum.  

UK PubMed Central (United Kingdom)

The management of certain plant beneficial microorganisms [biological control agents (BCAs)] seems to be a promising and environmental friendly method to control plant pathogens. However, applications are still limited because of the lack of consistency of BCAs when they are applied in the field. In the present paper, the advantages and limitations of BCAs are seen through the example of Pythium oligandrum, an oomycete that has received much attention in the last decade. The biological control exerted by P. oligandrum is the result of a complex process, which includes direct effects through the control of pathogens and/or indirect effects mediated by P. oligandrum, i.e. induction of resistance and growth promotion. P. oligandrum antagonism is a multifaceted and target fungus-dependent process. Interestingly, it does not seem to disrupt microflora biodiversity on the roots. P. oligandrum has an atypical relationship with the plant because it rapidly penetrates into the root tissues but it cannot stay alive in planta. After root colonisation, because of the elicitation by P. oligandrum of the plant-defence system, plants are protected from a range of pathogens. The management of BCAs, here P. oligandrum, is discussed with regard to its interactions with the incredibly complex agrosystems.

Gerbore J; Benhamou N; Vallance J; Le Floch G; Grizard D; Regnault-Roger C; Rey P

2013-05-01

215

Characterization of Pythium Transcriptome and Gene Expression Analysis at Different Stages of Fermentation.  

UK PubMed Central (United Kingdom)

BACKGROUND: The Pythium splendens is a potentially useful organism for the synthesis of large amounts of eicosapentaenoic acid. Peak biomass and lipid accumulation do not occur at the same time and growth temperature has an effect on the fatty acid composition. Little is known about the pathway or the genes involved in growth, lipid synthesis or temperature resistance in P. splendens. Analysis of the transcriptome and expression profile data for P.splendensRBB-5 were used to extend genetic information for this strain and to contribute to a comprehensive understanding of the molecular mechanisms involved in specific biological processes. METHODOLOGY/PRINCIPAL FINDINGS: This study used transcriptome assembly and gene expression analysis with short-read sequencing technology combined with a tag-based digital gene expression (DGE) system. Assembled sequences were annotated with gene descriptions, such as gene ontology (GO), clusters of orthologous group (COG) terms and KEGG orthology (KO) to generate 23,796 unigenes. In addition, we obtained a larger number of genes at different stages of fermentation (48, 100 and 148 h). The genes related to growth characteristics and lipid biosynthesis were analyzed in detail. Some genes associated with lipid and fatty acid biosynthesis were selected to confirm the digital gene expression (DGE) results by quantitative real-time PCR (qRT-PCR). CONCLUSION/SIGNIFICANCE: The transcriptome improves our genetic understanding of P.splendensRBB-5 greatly and makes a large number of gene sequences available for further study. Notably, the transcriptome and DGE profiling data of P.splendensRBB-5 provide a comprehensive insight into gene expression profiles at different stages of fermentation and lay the foundation for the study of optimizing lipid content and growth speed at the molecular level.

Zhu Y; Zhou P; Hu J; Zhang R; Ren L; Li M; Ning F; Chen W; Yu L

2013-01-01

216

Suppression of Pythium spp. by Trichoderma spp. during germination of tomato seeds in soilless growing media.  

Science.gov (United States)

In the Flemish horticulture Pythium spp. is an important pathogen of tomato plants (Lycopersicon esculenthum) in soilless growing media. Therefore some experiments were conducted to evaluate the possibility of decreasing the damage caused by Pythium spp. by Trichoderma spp. In a tray with several growing media, a suspension of Trichoderma conidia (10(6)/ml growing medium) was applied two weeks before sowing. On some objects, a compost extract (Biostimulus) was added. The growing media used in the experiment were rockwool, recycled rockwool and recycled coconut fibre. After sowing, the trays were covered with perlite. Three isolates of Trichoderma spp.: T. asperellum (Biofungus), T. harzianum (Tri 003) and Trichoderma sp. (KHK) and two isolates of Pythium spp.: P. ultimum (MUCL) en P. aphanidermatum (HRI, UK) were used. Propamocarb was used as a chemical standard. The use of coconut fibre growing medium resulted in a higher percentage (36%) of germination than the rockwool media when only Pythium spp. was used. The presence of the spontaneous developing microflora in the coconut fibre medium gave probably also a suppression of Pythium spp. For that reason the results of the suppression by Trichoderma spp. are not easy to explain and very variable on the different objects. Pythium ultimum was more suppressed than P. aphanidermatum on all the growing media and the application of all the Trichoderma isolates increased the germination percentage of tomato seeds. T. asperellum (Biofungus) gave on rockwool also a good result for the suppression of P. aphanidermatum (increasing of germination with 48%). This effect was comparable with the propamocarb treatment (48%). T. harzianum (Tri 003) gave a small suppression (22%) and Trichoderma sp. (KHK) gave almost no suppression of P. aphanidermatum (7%). When less Trichoderma conidia were applied the germination percentage decreased. The adding of a compost extract (Biostimulus) had no influence on the results. This experiment shows that application of Trichoderma conidia in the presence of Pythium spp. increases the germination percentage of tomato seeds, sowed in the used soilless growing media. PMID:12701442

Aerts, R; De Schutter, B; Rombouts, L

2002-01-01

217

Suppression of Pythium spp. by Trichoderma spp. during germination of tomato seeds in soilless growing media.  

UK PubMed Central (United Kingdom)

In the Flemish horticulture Pythium spp. is an important pathogen of tomato plants (Lycopersicon esculenthum) in soilless growing media. Therefore some experiments were conducted to evaluate the possibility of decreasing the damage caused by Pythium spp. by Trichoderma spp. In a tray with several growing media, a suspension of Trichoderma conidia (10(6)/ml growing medium) was applied two weeks before sowing. On some objects, a compost extract (Biostimulus) was added. The growing media used in the experiment were rockwool, recycled rockwool and recycled coconut fibre. After sowing, the trays were covered with perlite. Three isolates of Trichoderma spp.: T. asperellum (Biofungus), T. harzianum (Tri 003) and Trichoderma sp. (KHK) and two isolates of Pythium spp.: P. ultimum (MUCL) en P. aphanidermatum (HRI, UK) were used. Propamocarb was used as a chemical standard. The use of coconut fibre growing medium resulted in a higher percentage (36%) of germination than the rockwool media when only Pythium spp. was used. The presence of the spontaneous developing microflora in the coconut fibre medium gave probably also a suppression of Pythium spp. For that reason the results of the suppression by Trichoderma spp. are not easy to explain and very variable on the different objects. Pythium ultimum was more suppressed than P. aphanidermatum on all the growing media and the application of all the Trichoderma isolates increased the germination percentage of tomato seeds. T. asperellum (Biofungus) gave on rockwool also a good result for the suppression of P. aphanidermatum (increasing of germination with 48%). This effect was comparable with the propamocarb treatment (48%). T. harzianum (Tri 003) gave a small suppression (22%) and Trichoderma sp. (KHK) gave almost no suppression of P. aphanidermatum (7%). When less Trichoderma conidia were applied the germination percentage decreased. The adding of a compost extract (Biostimulus) had no influence on the results. This experiment shows that application of Trichoderma conidia in the presence of Pythium spp. increases the germination percentage of tomato seeds, sowed in the used soilless growing media.

Aerts R; De Schutter B; Rombouts L

2002-01-01

218

Sugarcane cropping and cattle husbandry integration  

Energy Technology Data Exchange (ETDEWEB)

This chapter approaches the Brazilian proposal to replace 5% of gasoline worldwide, mathematical programming and simulation of sugarcane-bioethanol and beef production in Brazil, modeling scenario of sugar cane and beef production in Brazil, mathematical modelling of sugarcane-bioethanol and beef production, modelling variables and constraints, objective function, optimized results of sugarcane-bioethanol and beef production in Brazil, and further potential applications.

Taube-Netto, Miguel; Pinto, Luis Franco de Campos; Castaneda-Ayarza, Juan; Cortez, Luis Augusto B.

2012-07-01

219

SUPPRESSION OF SEEDLING DAMPING-OFF CAUSED BY PYTHIUM ULTIMUM, PYTHIUM IRREGULARE, AND RHIZOCTONIA SOLANI IN CONTAINER MEDIA AMENDED WITH A DIVERSE RANGE OF PACIFIC NORTHWEST COMPOST SOURCES  

Science.gov (United States)

Suppression of seedling damping-off disease caused by Pythium spp. and Rhizoctonia solani is a potential benefit of formulating soilless container media with compost. Thirty six compost samples from Pacific Northwest commercial composting facilities were analyzed for a number of physical, chemical,...

220

Crescimento e produtividade agrícola de cana-de-açúcar em diferentes fontes de fósforo Growth and yield of sugarcane under different phosphorus sources  

Directory of Open Access Journals (Sweden)

Full Text Available Com o objetivo de avaliar o crescimento e a produtividade agrícola da cana-planta em diferentes fontes de fósforo, conduziu-se um experimento de campo em Coruripe, AL, com 10 tratamentos: 1. Testemunha; 2. NK + micro; 3. Superfosfato simples (SS); 4. Superfosfato triplo (ST); 5. Fosmag; 6. Gafsa; 7. MAP; 8. Fórmula 06-26-24 (460 kg ha-1); 9. Composto e 10. SSP - parcelado. O delineamento estatístico foi em blocos ao acaso com 4 repetições. Avaliaram-se: população de perfilhos, altura de plantas, Índice de Área Foliar (IAF), taxa de crescimento do colmo, taxa de produção de matéria fresca do colmo, taxa de crescimento relativo, rendimento agrícola e as concentrações foliares de P e os níveis disponíveis no solo. As fontes de fósforo não influenciaram o crescimento da cana-planta em função do efeito residual, proveniente de adubações anteriores, mas proporcionaram produtividades médias superiores a 80 t ha-1. O ST proporcionou o melhor rendimento agrícola na cana-planta a qual, por sua vez, apresentou três fases de crescimento: 1ª fase: intenso perfilhamento até 120 DAP; 2ª fase: grande crescimento de 120 a 240 DAP e 3ª fase: maturação dos 240 aos 360 DAP. As maiores taxas de crescimento e produção de matéria fresca do colmo ocorreram logo após a fase de intenso perfilhamento entre 120 e 240 DAP.This work had as its objective in the evaluation of the growth and production of the sugarcare plant under different phosphorus sources. The experiment was carried out in Coruripe, AL, Brazil with 10 fertilizer treatments: 1) Control; 2) NK + micronutrient; 3) Super Phosphate Simple; 4) Triple Super Phosphate; 5) Fosmag; 6) Gafsa; 7) MAP; 8) NPK 06-26-24 (460 kg ha-1); 9) Compost and 10) Simple Super Phosphate - splitdose. The experiment was in random blocks, with four replicates. Parameters evaluated were: number of tillers, height of plants, IAF, rate of stalk growth, rate of biomass production of the stalk, relative growth rate, production and P in leaf and available in soil. P sources did not show any significant influence upon the growth of cane-plant due to the residual effect of previous manuring, with average yield of 80 t ha-1. The triple super phosphate produced the best production in the cane-plant, which presented three growth phases: 1st phase: intense tillering until 120 days after planting (DAP); 2nd phase:intense growth between 120 and 240 DAP; and 3rd phase: maturation, between 240 and 360 DAP. The major growth rate and fresh matter stalk production occurred after intense tillering phase between 120 and 240 DAP.

Valdevan R. dos Santos; Gilson Moura Filho; Abel W. de Albuquerque; José P. V. da Costa; Cícero G. dos Santos; Alda C. I. dos Santos

2009-01-01

 
 
 
 
221

Crecimiento y acumulación de prolina en dos genotipos de caña de azúcar sometidos a salinización con cloruro de sodio Growth and proline accumulation in two sugarcane genotypes under sodium cloride salinization  

Directory of Open Access Journals (Sweden)

Full Text Available Se evaluaron en condiciones de cobertizo, dos genotipos de caña de azúcar con respuesta diferencial ante las sales: PR692176 (tolerante) y V78-1 (sensible), a fin de obtener información sobre las causas de ese comportamiento diferencial. Las plantas crecieron en un sustrato artificial (arena) irrigado con solución nutritiva y cuando tuvieron dos meses de edad se iniciaron los riegos con solución nutritiva a la que se añadió cloruro de sodio (100 mM). Se determinaron algunos componentes del crecimiento y la acumulación de prolina en raíces y en hojas de diferentes edades. La salinización con NaCl tuvo efecto negativo sobre el crecimiento de ambos genotipos, pero en el genotipo resistente el área foliar, peso seco de raíces y la relación peso seco del sistema radical/peso seco del sistema aéreo, se redujeron menos. La acumulación de prolina aumentó en las plantas salinizadas, especialmente en raíces y en las vainas foliares, siendo ese incremento mayor para el genotipo sensible, excepto en la lámina foliar de la hoja más recientemente expandida (hoja TVD).Two sugarcane genotypes differing in salinity response were evaluated: PR692176 (salt tolerant) and V78-1 (salt sensitive), in order to get information about the causes of that differential behavior. The plants grew in an artificial substrate (sand) irrigated with nutrient solution and after two months they were subjected to salinization with sodium chloride (100 mM). Some growth parameters and proline accumulation in roots and leaves of different ages were studied. Sodium chloride salinization affected the growth in both genotypes, however, the leaf area, root dry weight and root dry weight/shoot dry weigh ratio were less reducted in the resistant genotype. Proline accumulation was increased in response to salinization, mainly in roots and sheaths. Proline accumulation in the plants under salinization was greater in the sensitive genotype than in the resistant genotype, except in the blade of the leaf forming the top visible dew lap (TVD leaf).

M García; E Medina

2003-01-01

222

Crecimiento y acumulación de prolina en dos genotipos de caña de azúcar sometidos a salinización con cloruro de sodio/ Growth and proline accumulation in two sugarcane genotypes under sodium cloride salinization  

Scientific Electronic Library Online (English)

Full Text Available Abstract in spanish Se evaluaron en condiciones de cobertizo, dos genotipos de caña de azúcar con respuesta diferencial ante las sales: PR692176 (tolerante) y V78-1 (sensible), a fin de obtener información sobre las causas de ese comportamiento diferencial. Las plantas crecieron en un sustrato artificial (arena) irrigado con solución nutritiva y cuando tuvieron dos meses de edad se iniciaron los riegos con solución nutritiva a la que se añadió cloruro de sodio (100 mM). Se determinaro (more) n algunos componentes del crecimiento y la acumulación de prolina en raíces y en hojas de diferentes edades. La salinización con NaCl tuvo efecto negativo sobre el crecimiento de ambos genotipos, pero en el genotipo resistente el área foliar, peso seco de raíces y la relación peso seco del sistema radical/peso seco del sistema aéreo, se redujeron menos. La acumulación de prolina aumentó en las plantas salinizadas, especialmente en raíces y en las vainas foliares, siendo ese incremento mayor para el genotipo sensible, excepto en la lámina foliar de la hoja más recientemente expandida (hoja TVD). Abstract in english Two sugarcane genotypes differing in salinity response were evaluated: PR692176 (salt tolerant) and V78-1 (salt sensitive), in order to get information about the causes of that differential behavior. The plants grew in an artificial substrate (sand) irrigated with nutrient solution and after two months they were subjected to salinization with sodium chloride (100 mM). Some growth parameters and proline accumulation in roots and leaves of different ages were studied. Sodiu (more) m chloride salinization affected the growth in both genotypes, however, the leaf area, root dry weight and root dry weight/shoot dry weigh ratio were less reducted in the resistant genotype. Proline accumulation was increased in response to salinization, mainly in roots and sheaths. Proline accumulation in the plants under salinization was greater in the sensitive genotype than in the resistant genotype, except in the blade of the leaf forming the top visible dew lap (TVD leaf).

García, M; Medina, E

2003-04-01

223

Popularizing of Sugarcane Based Intercropping Systems in Non Millzone  

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Full Text Available A field experiment was conducted to study the popularity of different intercrops with sugarcane at Nakla thana under Sherpur district of Bangladesh during cropping year 2000-2001. Five intercrops with sugarcane combination such as potato (Solanum tuberosum), onion (Allium cepa), coriander (Coriandrum sativum), mustard (Brassica campestris) and garlic(Allium sativum) were studied against sole sugarcane crop. In respect of agronomic performances, sugarcane with potato, sugarcane with onion and sugarcane with coriander were suitable though they produce lower cane yield than sole cane. In respect of economic profitability sugarcane with potato combination was the most profitable and sugarcane with onion and sugarcane with coriander combination were 2nd and 3rd profitable combinations, respectively. In respect of adjusted yield sugarcane with potato was the best combination and sugarcane with onion was the 2nd combination than the sole cane yield. Sugarcane with mustard and sugarcane with garlic combination was found to be inferior in respect of agronomic yield, economic profitability and adjusted cane yield. Hence, The study reveals that sugarcane with potato, sugarcane with onion and sugarcane with coriander combination may be suggested as intercropping with sugarcane for non mill zone area of Sherpur district (AEZ 8) to get interim benefit from the same piece of land.

M.A.K. Al Azad; M.J. Alam

2004-01-01

224

Bagasse production from high fibre sugarcane hybrids  

Energy Technology Data Exchange (ETDEWEB)

Since 1975, 90% of the sugarcane bagasse produced by the Louisiana sugar industry is now used as a fuel for raw sugar production. Two sugarcane hybrid varieties which are too low in sucrose to be acceptable as commercial sugarcane varieties were tested for their biomass yield. Yields of over 100 tons of total biomass were obtained, resulting in over 30 tons of dry matter per acre per year, using conventional practices. This material could be grown on sub-optimal land in sufficient quantities to meet part of the needs of the sugarcane by-product industries who have been deprived of their source of bagasse.

Giamalva, M.J.; Clarke, S.; Bischoff, K.

1981-08-01

225

Survival of southern pine seedlings after inoculations with Pythium and cold storage in the presence of peat moss  

UK PubMed Central (United Kingdom)

Cold storing bareroot pine (Pinus spp.) seedlings grown in the southern U.S. for as little as 1?week in a cooler (just above freezing) in the fall (November to mid?December) has been shown to reduce seedling survival after outplanting. In contrast, survival of container?grown seedling is typically not affected when stored for 4?weeks in coolers in November and December. Wounds sustained by seedlings as they are lifted from nursery beds may allow Pythium spp. to infect bareroot seedling roots. Once in the cool, moist storage environment, Pythium multiplies and may result in seedling mortality after outplanting. Bareroot loblolly pine (Pinus taeda) and container?grown loblolly, longleaf (Pinus palustris), slash (Pinus elliottii) and shortleaf pine (Pinus echinata) seedlings were inoculated with either Pythium dimorphum or Pythium irregulare, cold stored with or without peat moss and monitored for survival after outplanting. Peat moss did not increase bareroot loblolly pine survival or reduce Pythium populations when seedlings were inoculated with Pythium prior to storage. Pythium irregulare reduced survival of longleaf and shortleaf pine grown in peat moss and perlite, respectively. Pythium did not affect loblolly or slash pine, but wounding their roots did reduce seedling survival when grown in containers.

Jackson DP; Enebak SA; South DB

2012-02-01

226

Effect of fungus gnat Bradysia impatiens (Diptera: Sciaridae) feeding on subsequent Pythium aphanidermatum infection of geranium seedlings (Pelargonium x hortorum)  

Science.gov (United States)

Dark-winged fungus gnats in the genus Bradysia (Diptera: Sciaridae) and root rot pathogens in the genus Pythium (Oomycetes) are important pests of greenhouse floriculture. Observations have pointed to a possible correlation between Pythium root rot disease and fungus gnat infestations; however, inte...

227

Population structure and genetic diversity of three species of Pythium isolated from forest tree nursery soils in Oregon and Washington  

Science.gov (United States)

The genus Pythium includes some of the most important soilborne pathogens that cause damping–off and root rot of conifers, resulting in high seedling mortality in forest tree nurseries. The aim of this study was to analyze the diversity and population structure of three species of Pythium (P. irregu...

228

Influence of Isolation method on mecovery of Pythium species from forest nursery soils in Oregon and Washington  

Science.gov (United States)

Pythium species are common damping off pathogens causing stunting, chlorosis, and death of conifer seedlings in the Pacific Northwest (PNW). Despite the prevalence and importance of these pathogens in forest nurseries, relatively little is known about the identity of Pythium species associated with...

229

Florescimento em cana-de-açúcar/ Flowering in sugarcane  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese O florescimento da cana-de-açúcar é um processo fisiológico complexo formado por vários estádios de desenvolvimento, e cada estádio tem a sua própria necessidade ambiental e fisiológica. Os fatores externos relacionados com o florescimento são: fotoperíodo, temperatura, umidade e radiação solar, além da fertilidade do solo. Por outro lado, os fatores internos envolvem fitocromo, hormônios, florígeno, ácidos nucleicos, dentre outros. A intensidade do proce (more) sso de florescimento e as consequências na qualidade da cana-de-açúcar variam com a variedade e com o clima. A redução do volume de caldo é o principal fator no qual o florescimento interfere, resultante do aumento do teor de fibras. Como as demais Poaceae, a cana-de-açúcar floresce, frutifica e morre, garantindo a perpetuação da espécie. Dessa forma, o homem procura interferir na natureza tentando evitar o florescimento da cana-de-açúcar, seja por meio de melhoramento genético ou por meio de reguladores vegetais. Em áreas comerciais de produção de cana-de-açúcar, onde há condições ideais para o florescimento da cultura, é recomendado o uso de variedade com potencial menos florífero. E, quando não é possível esse manejo varietal, o uso de inibidores do florescimento é a melhor alternativa para evitar mais perdas no conteúdo de sacarose. Abstract in english The sugarcane flowering is a complex physiological process that consists of several stages of development, each stage has its physiological and environmental requisition. The external factors related to flowering are: photoperiod, temperature, humidity, solar radiation in addition to soil fertility. Already the internal factors involved are: phytochrome, hormones, florigene, nucleic acids, among others. The intensity of the flowering and the consequences on the quality of (more) sugarcane vary with the variety and the climate. The reduction of the sugarcane juice is the main factor which affected by the flowering, resulting from due to the increased fiber content. As other Poaceae, the sugarcane flowers, fruit and dies, ensuring the perpetuation of the species. Thus, the man tries to interfere in nature, trying to prevent the flowering sugarcane, either through breeding or through plant growth regulators. In areas of sugarcane commercial production, where there are ideal conditions for the flowering culture, it is recommended the se of variety with lower potential of flowering. And when this varietal management is more difficult, the use of inhibitors of flowering is the best alternative to avoid more losses of sucrose content.

Araldi, Rosilaine; Silva, Ferdinando Marcos Lima; Ono, Elizabeth Orika; Rodrigues, João Domingues

2010-03-01

230

Influence of weeding regime on severity of sugarcane mosaic disease in selected improved sugarcane germplasm accessions in the Southern Guinea Savanna agroecology of Nigeria  

Directory of Open Access Journals (Sweden)

Full Text Available Experiment was conducted during 2011 to 2012 cropping season using potted plants, to evaluate the influence of weeding regime on sugarcane mosaic disease severity in selected improved sugarcane varieties from the University of Ilorin – Nigeria sugarcane germplasm. The experiment was laid out following a split plot arrangement where the weeding regime constitutes the main plot and the sugarcane varieties were the subplot. Disease parameters such as symptom manifestation, number of diseased leaves, percentage severity were measured. Growth and yield parameters such as stalk length, number of leaves, number of tillers and yield parameters such as fresh and dry shoot weights, percentage dry matter at harvest were also measured. Analysis of variance showed that percentage severity of sugarcane mosaic disease, increased in non-weeded plots compared with weeded plots. Twice weeding (52.1%) and the weed free plots (53.7%) had the significantly lowest severities. Varietal influence significantly influenced severity and variety NCO-270 produced the significantly lowest severity (45.8%).The interaction of weeding regime and variety indicated that variety CB36411 in the weed free plots, produced the lowest severity (33.5%).Yield parameters showed that significantly highest shoot weight was recorded in the weed free plot, while variety NCO-270 gave the highest fresh and dry shoot weights (254.8g and 50.2g respectively). The results indicate that variety NCO-270 was the most tolerant and that weeding at least once in six months is required to mitigate the effect of sugarcane mosaic disease, as witnessed in significantly increased growth and yield attributes of plants in the weeded plots.

Taiye Hussein Aliyu; Olusegun Samuel Balogun

2013-01-01

231

Identification of Resistance to Pythium ultimum in Sunflower Seedlings  

Directory of Open Access Journals (Sweden)

Full Text Available In order to evaluate Pythium-mediated damping-off a laboratory experiment was conducted at Biotech Research Center of the University of Zabol, in 2010. The experimental design was a completely randomized with seven genotypes, together with seven replicates. The seeds were inoculated in oospore suspension of fungi (105 mg/mL) for 1 min. After 5 days, seedlings were evaluated with an aim to counting non-germinated seeds, abnormal seedlings and healthy seedlings. Then the healthy seedlings were planted in pots after infecting seedlings through a piece of paper towels contaminated with fungal suspension, and normal seedlings were counted after 12 days. The result showed that there were significant differences among the genotypes for all evaluated traits. The greatest non-germinated seeds were observed in Azargol with 38% and followed by Record and Allstar. Azargol also had the highest abnormal seedlings (86%) and the minimum abnormal seedlings were observed in Xaria with 72%. Regarding normal seedlings at pot, Golshid and Hysun- 33 were superior with 60 and 49%, respectively. These findings suggest that all genotypes had a high susceptibility to P. ultimum. Also, results obtained from the paper towel experiment were different to the results of the soil.

Mohammad R. Asgharipour

2012-01-01

232

Disinfection of Pythium-infested recirculation water by UV-oxidation technology.  

UK PubMed Central (United Kingdom)

Selective disinfection against Pythium aphanidermatum in recirculation water was tested with UV-irradiation and with UV-oxidation technology with the objective to reduce the electrical energy consumption per cubic meter treated water. UV-oxidation technology is based on injection of hydrogen peroxide in recirculation water, just before passage along a UV-lamp, thus creating hydroxyl radicals. Pythium aphanidermatum was applied artificially to recirculation water from tomatoes, grown, in rockwool and coconut fibre. Other parameters in this study were pH and transmission value (T10) of the infested recirculation water. Results indicated that the recommended UV-C dose of 100 mJ/cm2 for elimination of fungal pathogens in general can be lowered in case recirculation water is infected with Pythium aphanidermatum only. When UV-oxidation technology was applied with 1 mmol hydrogen peroxide per litre recirculation water, the UV-C dose could be reduced even more in comparison with merely UV irradiation.

Runia WT; Boonstra S

2001-01-01

233

Long-term follow-up after successful treatment of Pythium insidiosum keratitis in Israel.  

Science.gov (United States)

The purpose of this project is to report a case of severe Pythium insidiosum keratitis confirmed by polymerase chain reaction (PCR), and its long-term cure after therapeutic penetrating keratoplasty. A 24-year-old woman with a history of contact lens wear and exposure to swimming pool water presented with a severe corneal abscess. She was treated with intensive fortified topical antibiotics and natamycin with limited response. Initial cultures suggested the presence of a septate mold, unclearly identified; therefore, both topical and intravenous voriconazole were administered. Despite the above treatment, there was worsening of the clinical picture. PCR assay revealed homology to Pythium insidiosum. Promptly, the patient underwent a large therapeutic penetrating keratoplasty. After five years of follow-up, the graft exhibits neither signs of rejection nor any recurrence of infection. We conclude that prompt identification of Pythium insidiosum keratitis and aggressive treatment by therapeutic penetrating keratoplasty may offer a cure to this disease. PMID:23627654

Barequet, Irina S; Lavinsky, Fabio; Rosner, Mordechai

2013-04-29

234

Long-term follow-up after successful treatment of Pythium insidiosum keratitis in Israel.  

UK PubMed Central (United Kingdom)

The purpose of this project is to report a case of severe Pythium insidiosum keratitis confirmed by polymerase chain reaction (PCR), and its long-term cure after therapeutic penetrating keratoplasty. A 24-year-old woman with a history of contact lens wear and exposure to swimming pool water presented with a severe corneal abscess. She was treated with intensive fortified topical antibiotics and natamycin with limited response. Initial cultures suggested the presence of a septate mold, unclearly identified; therefore, both topical and intravenous voriconazole were administered. Despite the above treatment, there was worsening of the clinical picture. PCR assay revealed homology to Pythium insidiosum. Promptly, the patient underwent a large therapeutic penetrating keratoplasty. After five years of follow-up, the graft exhibits neither signs of rejection nor any recurrence of infection. We conclude that prompt identification of Pythium insidiosum keratitis and aggressive treatment by therapeutic penetrating keratoplasty may offer a cure to this disease.

Barequet IS; Lavinsky F; Rosner M

2013-07-01

235

Fermentation of irradiated sugarcane must  

International Nuclear Information System (INIS)

Bacillus and Lactobacillus are bacteria that usually contaminate the ethanolic fermentation by yeasts and my influence yeast viability. As microorganisms can be killed by ionizing radiation, the efficacy of gamma radiation in reducing the population of certain contaminating bacteria from sugarcane must was examined and, as a consequence, the beneficial effect of lethal doses of radiation on some parameters of yeast-based ethanolic fermentation was verified. Must from sugarcane juice was inoculated with bacteria of the general Bacillus and Lactobacillus. The contaminated must was irradiated with 2.0, 4.0, 6.0, 8.0 and 10.0 kGy of gamma radiation. After ethanolic fermentation by the yeast (Saccharomyces cerevisiae) the total and volatile acidity produced during the process were evaluated: yeast viability and ethanol yield were also recorded. Treatments of gamma radiation reduced the population of the contaminating bacteria in the sugarcane must. The acidity produced during the fermentation decreased as the dose rate of radiation increased. Conversely, the yeast viability increased as the dose rate of radiation increased. Gamma irradiation was an efficient treatment to decontaminate the must and improved its parameters related to ethanolic fermentation, including ethanol yield, which increased 1.9%. (author)

2003-01-01

236

Fermentation of irradiated sugarcane must  

Energy Technology Data Exchange (ETDEWEB)

Bacillus and Lactobacillus are bacteria that usually contaminate the ethanolic fermentation by yeasts and my influence yeast viability. As microorganisms can be killed by ionizing radiation, the efficacy of gamma radiation in reducing the population of certain contaminating bacteria from sugarcane must was examined and, as a consequence, the beneficial effect of lethal doses of radiation on some parameters of yeast-based ethanolic fermentation was verified. Must from sugarcane juice was inoculated with bacteria of the general Bacillus and Lactobacillus. The contaminated must was irradiated with 2.0, 4.0, 6.0, 8.0 and 10.0 kGy of gamma radiation. After ethanolic fermentation by the yeast (Saccharomyces cerevisiae) the total and volatile acidity produced during the process were evaluated: yeast viability and ethanol yield were also recorded. Treatments of gamma radiation reduced the population of the contaminating bacteria in the sugarcane must. The acidity produced during the fermentation decreased as the dose rate of radiation increased. Conversely, the yeast viability increased as the dose rate of radiation increased. Gamma irradiation was an efficient treatment to decontaminate the must and improved its parameters related to ethanolic fermentation, including ethanol yield, which increased 1.9%. (author)

Alcarde, Andre Ricardo; Horii, Jorge [Sao Paulo Univ., Piracicaba, SP (Brazil). Escola Superior de Agricultura Luiz de Queiroz. Dept. de Agroindustria, Alimentos e Nutricao]. E-mail: aralcard@esalq.usp.br; Walder, Julio Marcos Melges [Centro de Energia Nuclear na Agricultura (CENA), Piracicaba, SP (Brazil). Lab. de Irradiacao de Alimentos e Radioentomologia

2003-12-01

237

Collection of sugarcane crop residue for energy  

Energy Technology Data Exchange (ETDEWEB)

Crop residue left after sugarcane harvesting was recovered using a forage harvester and a large round baler. The quantity, bulk density and moisture content of the crop residue was determined in four fields. Crop residue from 7 ha was burned in boilers at a sugar mill. Samples of this residue were tested by a laboratory and compared to sugarcane bagasse.

Eiland, B.R.; Clayton, J.E.

1982-12-01

238

Exploring Broad Genetic Resources Available to Sugarcane  

Science.gov (United States)

Sugarcane (Saccharum spp.) is used for sugar and energy. It has a high photosynthetic efficiency and is one of the most productive crops globally. Breeders of energycane and sugarcane have overlapping goals in creating cultivars that resist biotic and abiotic stresses. The World Collection of Sugarc...

239

Sugarcane genes associated with sucrose content  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract Background - Sucrose content is a highly desirable trait in sugarcane as the worldwide demand for cost-effective biofuels surges. Sugarcane cultivars differ in their capacity to accumulate sucrose and breeding programs routinely perform crosses to identify genotypes able to...

Papini-Terzi Flávia S; Rocha Flávia R; Vêncio Ricardo ZN; Felix Juliana M; Branco Diana S; Waclawovsky Alessandro J

240

Elimination of five sugarcane viruses from sugarcane using in vitro culture of axillary bud and apical meristem  

Science.gov (United States)

Procedures were developed for the in vitro elimination of Sugarcane mosaic virus (SCMV), Sorghum mosaic virus (SrMV), Sugarcane streak mosaic virus (SCSMV), Sugarcane yellow leaf virus (SCYLV) and Fiji disease virus (FDV) from infected sugarcane. In vitro shoot regeneration, elongation and virus el...

 
 
 
 
241

Pythium root rot of common bean: biology and control methods. A review  

Directory of Open Access Journals (Sweden)

Full Text Available Pythium root rot constitutes a highly damaging constraint on the common bean, Phaseolus vulgaris L., grown in several areas of Eastern and Central Africa. Here, this food legume is cultivated intensively under poor conditions of crop rotation due to the exiguity of the land in the region. Yield losses of up to 70% in traditional local bean cultivars have been reported in Kenya and Rwanda. In this study, a detailed analysis of the biology and diversity of the Pythium genus was carried out in order to understand the mechanisms leading to the development of the disease. Various control methods for reducing the damage provoked by this disease were analyzed.

Nzungize, JR.; Lyumugabe, F.; Busogoro, JP.; Baudoin, JP.

2012-01-01

242

Status of the Pythiaceae (Straminipila) in Argentina: I. The GenusPythium Status de la familia Pythiaceae (Reino Straminipila) en Argentina: I. El género Pythium  

Directory of Open Access Journals (Sweden)

Full Text Available The genus Pythium (Pythiaceae (Peronosporomycetes - ex Oomycetes), Kingdom Straminipila) includes important pathogens, affecting a wide range of hosts of economic value, causing damping-off and decline of herbaceous and wooded plants due to rootlets rot. In order to acquire a more comprehensive vision of Pythium in Argentina, a review and an updated report of recent progress in this matter was carried out since the first reports in the late XIX century till October 2009. Information was taken from printed and on line primary and secondary sources such as Proceedings of national and international Scientific Meetings, Bulletins from National Institutions and Universities, periodical Journals, books and data bases. The information was analyzed and categorized, thus updating the number of species of this genus, their geographical distribution, hosts affected, and symptoms. So far 18 species have been cited affecting, 247 hosts. The greatest number of hosts is affected by P. ultimum and P. debaryanum, followed by P. irregulare and P. aphanidermatum. The diversity of Pythium species in the world suggests that perhaps a wider variety of species, still not cited, could be present in Argentina. Projects dedicated to surveying the presence and identification of Pythium spp are necessary.El género Pythium (Pythiaceae (Peronosporomycetes-ex Oomycetes), Straminipila) incluye patógenos que afectan hospedantes de importancia económica, ocasionando damping off en pre y postemergencia de plántulas de almácigo y el declinamiento de plantas herbáceas y adultas por destrucción de las raíces absorbentes. Con la finalidad de conocer el estado actual de la información disponible sobre este género en Argentina, se llevó a cabo una revisión desde los primeros reportes a fines del siglo XIX hasta octubre de 2009. Se consultaron fuentes primarias y secundarias de información escrita y electrónica: presentaciones en congresos nacionales e internacionales, publicaciones periódicas nacionales e internacionales, boletines de instituciones y universidades, libros y bases de datos. La información obtenida fue categorizada y analizada permitiendo conocer el número de especies de este género, su distribución geográfica y por tipo de cultivos, relaciones hospedante-patógeno involucradas y la sintomatología observada. Se encuentran citadas 18 especies que afectan a 247 hospedantes. Un elevado número de hospedantes fueron afectados por P. ultimum y P. debaryanum, seguidos por P. irregulare y P. aphanidermatum. La diversidad de especies de Pythium en el mundo sugiere que un mayor número de especies podrían estar presentes en el país, siendo necesario su relevamiento e identificación.

Hemilse E Palmucci; Silvia M Wolcan; Pablo E Grijalba

2011-01-01

243

Status of the Pythiaceae (Straminipila) in Argentina: I. The GenusPythium/ Status de la familia Pythiaceae (Reino Straminipila) en Argentina: I. El género Pythium  

Scientific Electronic Library Online (English)

Full Text Available Abstract in spanish El género Pythium (Pythiaceae (Peronosporomycetes-ex Oomycetes), Straminipila) incluye patógenos que afectan hospedantes de importancia económica, ocasionando damping off en pre y postemergencia de plántulas de almácigo y el declinamiento de plantas herbáceas y adultas por destrucción de las raíces absorbentes. Con la finalidad de conocer el estado actual de la información disponible sobre este género en Argentina, se llevó a cabo una revisión desde los primer (more) os reportes a fines del siglo XIX hasta octubre de 2009. Se consultaron fuentes primarias y secundarias de información escrita y electrónica: presentaciones en congresos nacionales e internacionales, publicaciones periódicas nacionales e internacionales, boletines de instituciones y universidades, libros y bases de datos. La información obtenida fue categorizada y analizada permitiendo conocer el número de especies de este género, su distribución geográfica y por tipo de cultivos, relaciones hospedante-patógeno involucradas y la sintomatología observada. Se encuentran citadas 18 especies que afectan a 247 hospedantes. Un elevado número de hospedantes fueron afectados por P. ultimum y P. debaryanum, seguidos por P. irregulare y P. aphanidermatum. La diversidad de especies de Pythium en el mundo sugiere que un mayor número de especies podrían estar presentes en el país, siendo necesario su relevamiento e identificación. Abstract in english The genus Pythium (Pythiaceae (Peronosporomycetes - ex Oomycetes), Kingdom Straminipila) includes important pathogens, affecting a wide range of hosts of economic value, causing damping-off and decline of herbaceous and wooded plants due to rootlets rot. In order to acquire a more comprehensive vision of Pythium in Argentina, a review and an updated report of recent progress in this matter was carried out since the first reports in the late XIX century till October 2009. (more) Information was taken from printed and on line primary and secondary sources such as Proceedings of national and international Scientific Meetings, Bulletins from National Institutions and Universities, periodical Journals, books and data bases. The information was analyzed and categorized, thus updating the number of species of this genus, their geographical distribution, hosts affected, and symptoms. So far 18 species have been cited affecting, 247 hosts. The greatest number of hosts is affected by P. ultimum and P. debaryanum, followed by P. irregulare and P. aphanidermatum. The diversity of Pythium species in the world suggests that perhaps a wider variety of species, still not cited, could be present in Argentina. Projects dedicated to surveying the presence and identification of Pythium spp are necessary.

Palmucci, Hemilse E; Wolcan, Silvia M; Grijalba, Pablo E

2011-12-01

244

Effect of silicon soil amendment on performance of sugarcane borer, Diatraea saccharalis (Lepidoptera:Crambidae) on rice.  

UK PubMed Central (United Kingdom)

The sugarcane borer, Diatraea saccharalis (F.), is a pest of graminaceous crops in the southern USA, including sugarcane, maize, and rice. This study was conducted to investigate the effect of silicon (Si) soil amendments on performance of sugarcane borer, D. saccharalis, on two rice cultivars, Cocodrie and XL723. There was a significant increase in the Si content of rice plants supplemented with calcium silicate as compared to non-treated plants. Soil Si amendment led to lower relative growth rates (RGRs) and reduced boring success of sugarcane borer larvae. Effects of soil Si amendments on borer success and RGR appeared to be more pronounced in 'Cocodrie', the cultivar relatively susceptible to borers, than in the moderately resistant cultivar, XL723. Soil Si amendment may contribute to the management of D. saccharalis through reduced feeding injury and increased exposure to adverse environmental conditions and natural enemies arising from reduced boring success.

Sidhu JK; Stout MJ; Blouin DC; Datnoff LE

2013-07-01

245

Reguladores vegetais no enraizamento e desenvolvimento de gemas de cana-de-açúcar tratadas termicamente/ Plant regulators on rooting and growth of sugarcane shoots treated with high temperature  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese Este trabalho teve por finalidade estudar o efeito de reguladores vegetais sobre a emergência e desenvolvimento inicial de gemas de cana-de-açúcar 'IAC 52-150', submetidas ao tratamento térmico por via úmida. Para tanto, as gemas foram tratadas durante uma hora em soluções de ácido indolilacético (IAA) e ácido naftalenacêtico (NAA), nas concentrações de 10, 25, 50 e 100 ppm, em ácido indolbutírico (IBA) nas concentrações de 10 e 25 ppm e em água pura (te (more) stemunha). Imediatamente após o tratamento, as gemas foram plantadas em germinadores de areia. IBA 10 ppm tendeu a favorecer a emergência e o enraizamento das gemas. IAA não afetou a emergência, enraizamento e peso da parte aérea da cana-de-açúcar. Aplicação de NAA 100 ppm reduziu a porcentagem de emergência e o peso da parte aérea do cultivar IAC 52-150. Abstract in english The effect of growth regulators on the germination and initial development of sugar cane shoots submitted to high temperature treatment by the moist method was studied. The shoots were treated during 1 hour with indoleacetic´acid (IAA) and naphthaleneacetic acid (NAA) at the concentrations of 10, 25, 50 and 100 ppm, with indolebutyric acid (IBA) at the concentrations of 10 and 25 ppm and with pure water (control). Immediately after the treatment, the shoots were planted (more) in sand germinators. The results showed that treatment with IBA 10 ppm promote a tendency to induce germination and roots development. The root system development was not affected by other treatments, but the development of the aerial portion was adversely affected by NAA 100 ppm. The results showed that, after 60 days, the number of emerged shoots was significantly lower than that of the control in the plots treated with 100 ppm of NAA.

Verri, A.R.; Pitelli, R.A.; Casagrande, A.A.; Castro, P.R.C.

1983-01-01

246

Effect of the indigenous microflora on the development of root and crown rot caused by Pythium aphanidermatum in cucumber grown on rockwool.  

UK PubMed Central (United Kingdom)

The capacity of the microflora in rockwool to suppress Pythium aphanidermatum, the causative agent of root and crown rot in cucumber, was assessed. Disease development of cucumber (Cucumis sativus) grown on rockwool was evaluated in an "ebb-and-flood" system with a recirculating nutrient solution after inoculation with P. aphanidermatum. In five independent experiments from 1995 to 1998, 11 batches of used rockwool were tested. All batches without P. aphanidermatum problems in the preceding cucumber crop had significantly lower numbers of diseased plants in nonautoclaved than in autoclaved used rockwool; the disease incidence was reduced by 52 to 100%. Suppressiveness also was present in rockwool previously used to grow other vegetable crops. Rockwool originating from a cucumber crop that was severely attacked by Pythium resulted in a high disease incidence. Previously unused (new) rockwool had higher or similar percentages of diseased plants than did nonsterilized used rockwool. Disease suppression in used rockwool could also be measured in a smaller test system. In both systems, autoclaved rockwool became suppressive to Pythium after recolonization with the indigenous microflora. Population sizes of total culturable aerobic bacteria as well as of fluorescent pseudomonads did not correlate with disease suppressiveness, as numbers of bacteria and pseudomonads were similar or lower in nonautoclaved (suppressive) than in autoclaved (nonsuppressive) rockwool. Differences in the structure of the bacterial populations could be visualized by using eubacterial polymerase chain reaction (PCR) followed by denaturing gradient gel electrophoresis (DGGE). Interestingly, the nonautoclaved and the recolonized used rockwool, which were both suppressive, showed different dominating bacterial groups as compared with the autoclaved rockwool. PCR-DGGE patterns obtained at different sampling times showed that the composition of the bacterial populations changed during plant growth. Fungal populations were present in the treatments that yielded suppressive rockwool, i.e., the nonautoclaved and the recolonized rockwool, which permitted a high disease incidence. Suppressiveness of rockwool to Pythium root and crown rot is a hitherto undescribed phenomenon, and knowledge of the mechanism and microorganisms involved will stimulate the development of microbially balanced soilless growing systems.

Postma J; Willemsen-De Klein MJEIM; Elsas JDvan

2000-02-01

247

Effect of the Indigenous Microflora on the Development of Root and Crown Rot Caused by Pythium aphanidermatum in Cucumber Grown on Rockwool.  

Science.gov (United States)

ABSTRACT The capacity of the microflora in rockwool to suppress Pythium aphanidermatum, the causative agent of root and crown rot in cucumber, was assessed. Disease development of cucumber (Cucumis sativus) grown on rockwool was evaluated in an "ebb-and-flood" system with a recirculating nutrient solution after inoculation with P. aphanidermatum. In five independent experiments from 1995 to 1998, 11 batches of used rockwool were tested. All batches without P. aphanidermatum problems in the preceding cucumber crop had significantly lower numbers of diseased plants in nonautoclaved than in autoclaved used rockwool; the disease incidence was reduced by 52 to 100%. Suppressiveness also was present in rockwool previously used to grow other vegetable crops. Rockwool originating from a cucumber crop that was severely attacked by Pythium resulted in a high disease incidence. Previously unused (new) rockwool had higher or similar percentages of diseased plants than did nonsterilized used rockwool. Disease suppression in used rockwool could also be measured in a smaller test system. In both systems, autoclaved rockwool became suppressive to Pythium after recolonization with the indigenous microflora. Population sizes of total culturable aerobic bacteria as well as of fluorescent pseudomonads did not correlate with disease suppressiveness, as numbers of bacteria and pseudomonads were similar or lower in nonautoclaved (suppressive) than in autoclaved (nonsuppressive) rockwool. Differences in the structure of the bacterial populations could be visualized by using eubacterial polymerase chain reaction (PCR) followed by denaturing gradient gel electrophoresis (DGGE). Interestingly, the nonautoclaved and the recolonized used rockwool, which were both suppressive, showed different dominating bacterial groups as compared with the autoclaved rockwool. PCR-DGGE patterns obtained at different sampling times showed that the composition of the bacterial populations changed during plant growth. Fungal populations were present in the treatments that yielded suppressive rockwool, i.e., the nonautoclaved and the recolonized rockwool, but they were absent or present in low numbers in the autoclaved rockwool, which permitted a high disease incidence. Suppressiveness of rockwool to Pythium root and crown rot is a hitherto undescribed phenomenon, and knowledge of the mechanism and microorganisms involved will stimulate the development of microbially balanced soilless growing systems. PMID:18944600

Postma, J; Willemsen-de Klein, M J; van Elsas, J D

2000-02-01

248

Study on Bt Susceptibility and Resistance Mechanisms in the Sugarcane Borer, Diatraea saccharalis  

Science.gov (United States)

Dose response and growth inhibition of Cry1Ab-susceptible and -resistant strains of the sugarcane borer, Diatraea saccharalis, were evaluated with Cry1Aa and Cry1Ac toxins. The median lethal concentration (LC50) of the Cry1Ab-resistant strain was estimated to be >80- and 45-fold greater than that of...

249

Characterization of major hydrolytic enzymes secreted by Pythium myriotylum, causative agent for soft rot disease.  

Science.gov (United States)

Pythium myriotylum, an oomycetous necrotroph is the causal agent of soft rot disease affecting several crops. Successful colonization by necrotrophs depends on their secretion of a diverse array of plant cell wall degrading enzymes (CWDEs). The induction dynamics of CWDEs secreted by P. myriotylum was analysed as little information is available for this pathogen. Activities of CWDEs that included pectinase, cellulase, xylanase and protease were detected using radial diffusion assay and differential staining. In Czapek Dox minimal medium supplemented with respective substrates as carbon source, the increase in CWDE activities was observed till 8 days of incubation after which a gradual decline in enzymatic activities was observed. With sucrose as sole carbon source, all the enzymes studied showed increase in activity with fungal growth while with cell wall material derived from ginger rhizome as sole carbon source, an initial spurt in cellulase, xylanase and pectinase activities was observed 3 days post incubation while protease activity increased from three days of incubation and reached maximum at 13 days of incubation. To further evaluate the role of CWDEs in pathogenicity, UV-induced mutants (pmN14uv1) were generated wherein significant reduction in cellulase, pectinase and protease activities were observed while that of xylanase remained unchanged compared to wild type isolate (RGCBN14). Bioassays indicated changes in infection potential of pmN14uv1 thereby suggesting the crucial role played by P. myriotylum CWDEs in initiating the rotting process. Hence appropriate strategies that target the production/activity of these secretory hydrolytic enzymes will help in reducing disease incidence/pathogen virulence. PMID:23897210

Geethu, C; Resna, A K; Nair, R Aswati

2013-07-30

250

Characterization of major hydrolytic enzymes secreted by Pythium myriotylum, causative agent for soft rot disease.  

UK PubMed Central (United Kingdom)

Pythium myriotylum, an oomycetous necrotroph is the causal agent of soft rot disease affecting several crops. Successful colonization by necrotrophs depends on their secretion of a diverse array of plant cell wall degrading enzymes (CWDEs). The induction dynamics of CWDEs secreted by P. myriotylum was analysed as little information is available for this pathogen. Activities of CWDEs that included pectinase, cellulase, xylanase and protease were detected using radial diffusion assay and differential staining. In Czapek Dox minimal medium supplemented with respective substrates as carbon source, the increase in CWDE activities was observed till 8 days of incubation after which a gradual decline in enzymatic activities was observed. With sucrose as sole carbon source, all the enzymes studied showed increase in activity with fungal growth while with cell wall material derived from ginger rhizome as sole carbon source, an initial spurt in cellulase, xylanase and pectinase activities was observed 3 days post incubation while protease activity increased from three days of incubation and reached maximum at 13 days of incubation. To further evaluate the role of CWDEs in pathogenicity, UV-induced mutants (pmN14uv1) were generated wherein significant reduction in cellulase, pectinase and protease activities were observed while that of xylanase remained unchanged compared to wild type isolate (RGCBN14). Bioassays indicated changes in infection potential of pmN14uv1 thereby suggesting the crucial role played by P. myriotylum CWDEs in initiating the rotting process. Hence appropriate strategies that target the production/activity of these secretory hydrolytic enzymes will help in reducing disease incidence/pathogen virulence.

Geethu C; Resna AK; Nair RA

2013-11-01

251

Diphenyl diselenide in vitro and in vivo activity against the oomycete Pythium insidiosum.  

UK PubMed Central (United Kingdom)

This study evaluated the in vitro activity of diphenyl diselenide against 19 Pythium insidiosum isolates and the in vivo therapeutic response of rabbits with experimentally induced pythiosis. In vitro: susceptibility tests were performed using the broth macrodilution method in accordance with the CLSI document M38-A2. The criteria for interpretation were as follows: MIC-1 and MIC-2 (inhibition of 90% and 100% of mycelium growth, respectively) and the minimum fungicide concentration (MIC-3). In vivo: twenty rabbits were divided into four groups with five animals each and treated for 40 consecutive days: groups 1 and 2 (experimentally induced pythiosis) were treated with diphenyl diselenide (10mg/kg/day) and canola oil (1 mL/kg/day), respectively; groups 3 and 4 (controls) were treated with canola oil (1 mL/kg/day) and diphenyl diselenide (10mg/kg/day), respectively. Toxicity was evaluated using biochemical and haematological parameters. In vitro susceptibility tests showed that 89.4% of isolates had a MIC-1 ? 0.5 ?g/mL, 84.2% of isolates had a MIC-2 ? 1.0 ?g/mL and 94.7% of isolates had a MIC-3 ? 2.0 ?g/mL. The in vivo assay suggested that this compound has a fungistatic activity, and the biochemical and haematological parameters indicated that there was no renal, hepatic or haematological toxicity. The comparison of the unsaturated iron binding capacity levels between animals with and without pythiosis suggested the involvement of iron metabolism in the pathogenesis of pythiosis. This study demonstrated the absence of detectable toxicity caused by diphenyl diselenide and the in vitro fungicidal and in vivo fungistatic activities of this drug, which makes it an option for future therapeutic approaches in the treatment of pythiosis.

Loreto ES; Alves SH; Santurio JM; Nogueira CW; Zeni G

2012-04-01

252

Diphenyl diselenide in vitro and in vivo activity against the oomycete Pythium insidiosum.  

Science.gov (United States)

This study evaluated the in vitro activity of diphenyl diselenide against 19 Pythium insidiosum isolates and the in vivo therapeutic response of rabbits with experimentally induced pythiosis. In vitro: susceptibility tests were performed using the broth macrodilution method in accordance with the CLSI document M38-A2. The criteria for interpretation were as follows: MIC-1 and MIC-2 (inhibition of 90% and 100% of mycelium growth, respectively) and the minimum fungicide concentration (MIC-3). In vivo: twenty rabbits were divided into four groups with five animals each and treated for 40 consecutive days: groups 1 and 2 (experimentally induced pythiosis) were treated with diphenyl diselenide (10mg/kg/day) and canola oil (1 mL/kg/day), respectively; groups 3 and 4 (controls) were treated with canola oil (1 mL/kg/day) and diphenyl diselenide (10mg/kg/day), respectively. Toxicity was evaluated using biochemical and haematological parameters. In vitro susceptibility tests showed that 89.4% of isolates had a MIC-1 ? 0.5 ?g/mL, 84.2% of isolates had a MIC-2 ? 1.0 ?g/mL and 94.7% of isolates had a MIC-3 ? 2.0 ?g/mL. The in vivo assay suggested that this compound has a fungistatic activity, and the biochemical and haematological parameters indicated that there was no renal, hepatic or haematological toxicity. The comparison of the unsaturated iron binding capacity levels between animals with and without pythiosis suggested the involvement of iron metabolism in the pathogenesis of pythiosis. This study demonstrated the absence of detectable toxicity caused by diphenyl diselenide and the in vitro fungicidal and in vivo fungistatic activities of this drug, which makes it an option for future therapeutic approaches in the treatment of pythiosis. PMID:22055205

Loreto, Erico Silva; Alves, Sydney Hartz; Santurio, Janio Morais; Nogueira, Cristina Wayne; Zeni, Gilson

2011-10-15

253

Characterization of major hydrolytic enzymes secreted by Pythium myriotylum, causative agent for soft rot disease.  

UK PubMed Central (United Kingdom)

Pythium myriotylum, an oomycetous necrotroph is the causal agent of soft rot disease affecting several crops. Successful colonization by necrotrophs depends on their secretion of a diverse array of plant cell wall degrading enzymes (CWDEs). The induction dynamics of CWDEs secreted by P. myriotylum was analysed as little information is available for this pathogen. Activities of CWDEs that included pectinase, cellulase, xylanase and protease were detected using radial diffusion assay and differential staining. In Czapek Dox minimal medium supplemented with respective substrates as carbon source, the increase in CWDE activities was observed till 8 days of incubation after which a gradual decline in enzymatic activities was observed. With sucrose as sole carbon source, all the enzymes studied showed increase in activity with fungal growth while with cell wall material derived from ginger rhizome as sole carbon source, an initial spurt in cellulase, xylanase and pectinase activities was observed 3 days post incubation while protease activity increased from three days of incubation and reached maximum at 13 days of incubation. To further evaluate the role of CWDEs in pathogenicity, UV-induced mutants (pmN14uv1) were generated wherein significant reduction in cellulase, pectinase and protease activities were observed while that of xylanase remained unchanged compared to wild type isolate (RGCBN14). Bioassays indicated changes in infection potential of pmN14uv1 thereby suggesting the crucial role played by P. myriotylum CWDEs in initiating the rotting process. Hence appropriate strategies that target the production/activity of these secretory hydrolytic enzymes will help in reducing disease incidence/pathogen virulence.

Geethu C; Resna AK; Nair RA

2013-07-01

254

Aislamiento y patogenicidad de un posible Pythium aphanidermatum en Jatropha Curcas L. no tóxica/ Isolation and pathogenicity of a possible Pythium aphanidermatum in Jatropha Curcas L. non toxic  

Scientific Electronic Library Online (English)

Full Text Available Abstract in spanish Un cromista, posible Pythium aphanidermatum, fue aislado de semillas y plántulas recién emergidas de semillas de Jatropha curcas L. no tóxica severamente dañadas sembradas en la región tropical de Veracruz, México. Para estudiar su efecto sobre las etapas de pre y post-emergencia, el patógeno aislado fue inoculado en semillas y plántulas de reciente emergencia. Se corroboró un cierto potencial patogénico en la etapa de pre-emergencia, que no fue estadísticamente significativo en la etapa post-emergente a mediano plazo. Abstract in english A chromista, possible Pythium aphanidermatum, was isolated from severely damage seeds and seedlings recently started from Jatropha curcas L. non toxic seeds sown in the tropical area of Veracruz, Mexico. In order to study pathogenic Pythium aphanidermatum effects over pre-emergent and post-emergent stages, seeds and young seedlings were inoculated with the isolated pathogen, and the chromista showed possible pathogenic activity against pre-emergency and recently started post-emergency; however, statistically significant damaged was not found in older seedlings.

Valdés Rodríguez, Ofelia Andrea; García Espinoza, Roberto; Sánchez Sánchez, Odilón; Pérez Vazquez, Arturo

2011-08-01

255

Factors Affecting Sugarcane Production in Pakistan  

Directory of Open Access Journals (Sweden)

Full Text Available This study was undertaken to identify the factors affecting sugarcane production in Pakistan. Data were collected from 387 sugarcane growers from Sindh, Punjab and NWFP province. Data were collected during the period 2007-08. The study reveals that the costs of inputs of sugarcane i.e. urea, DAP, FYM, land preparation, seed and its application, weeding and cost of irrigation were the important factors which influenced on the returns of sugarcane growers. The effectiveness was examined by using the Cobb-Douglas production function; MVP and allocative efficiency were calculated. The coefficient of multiple determinations R2 was 0.9249, which indicated that 92% variation in the cost of inputs was explained by all explanatory variables and the adjusted R2 was 92%. The F-value was 666.94 and was highly significant at 5% level of significance, indicating that the regression model was well fitted. The high prices of inputs, low price of output, delay in payments and lack of scientific knowledge were the major problems in sugarcane production. In order to enhance the productivity of sugarcane in the country, government should solve the identified problems to increase the income of sugarcane growers.

Adnan Nazir; Ghulam Ali Jariko; Mumtaz Ali Junejo

2013-01-01

256

An-Overview on invertase in sugarcane.  

Science.gov (United States)

Saccharum officinarum is one of the most cultivated hybrid varieties among the sugarcane varieties. In sugarcane plant sucrose is the major carbohydrate which can be stored and transported. Different physiological and biochemical studies on this crop report that invertase activity and sucrose concentration some how are key limiting step in the process of sucrose accumulation. Significant efforts have been made in relation to the sucrose cycle by altering the sucrose phosphate synthetase, sucrose synthetase and invertase. In sugarcane two types of invertase enzymes have been reported on the basis of pH and cellular localization. Invertase breaks the sucrose into hexoses as a source of energy and carbon. It has also been reported that this enzyme is involved in the process of cell differentiation and plant development. Progress has been made for the understanding of invertase activity and its role in sugarcane plant. With the help of biotechnology it is possible to target the desired gene with genetic engineering approach to increase sucrose content by careful manipulation of invertase (enzyme) gene to increase the sucrose yield in sugarcane. Purpose of this mini review is to high-light the role of invertase in sugarcane and how to overcome sucrose recovery in sugarcane. PMID:23847400

Ansari, Mohammad Israil; Yadav, Ashok; Lal, Ramji

2013-05-25

257

An-Overview on invertase in sugarcane.  

UK PubMed Central (United Kingdom)

Saccharum officinarum is one of the most cultivated hybrid varieties among the sugarcane varieties. In sugarcane plant sucrose is the major carbohydrate which can be stored and transported. Different physiological and biochemical studies on this crop report that invertase activity and sucrose concentration some how are key limiting step in the process of sucrose accumulation. Significant efforts have been made in relation to the sucrose cycle by altering the sucrose phosphate synthetase, sucrose synthetase and invertase. In sugarcane two types of invertase enzymes have been reported on the basis of pH and cellular localization. Invertase breaks the sucrose into hexoses as a source of energy and carbon. It has also been reported that this enzyme is involved in the process of cell differentiation and plant development. Progress has been made for the understanding of invertase activity and its role in sugarcane plant. With the help of biotechnology it is possible to target the desired gene with genetic engineering approach to increase sucrose content by careful manipulation of invertase (enzyme) gene to increase the sucrose yield in sugarcane. Purpose of this mini review is to high-light the role of invertase in sugarcane and how to overcome sucrose recovery in sugarcane.

Ansari MI; Yadav A; Lal R

2013-01-01

258

An-Overview on invertase in sugarcane  

Directory of Open Access Journals (Sweden)

Full Text Available Saccharum officinarum is one of the most cultivated hybrid varieties among the sugarcane varieties. In sugarcane plant sucrose is the major carbohydrate which can be stored and transported. Different physiological and biochemical studies on this crop report that invertase activity and sucrose concentration some how are key limiting step in the process of sucrose accumulation. Significant efforts have been made in relation to the sucrose cycle by altering the sucrose phosphate synthetase, sucrose synthetase and invertase. In sugarcane two types of invertase enzymes have been reported on the basis of pH and cellular localization. Invertase breaks the sucrose into hexoses as a source of energy and carbon. It has also been reported that this enzyme is involved in the process of cell differentiation and plant development. Progress has been made for the understanding of invertase activity and its role in sugarcane plant. With the help of biotechnology it is possible to target the desired gene with genetic engineering approach to increase sucrose content by careful manipulation of invertase (enzyme) gene to increase the sucrose yield in sugarcane. Purpose of this mini review is to high-light the role of invertase in sugarcane and how to overcome sucrose recovery in sugarcane.

Mohammad Israil Ansari; Ashok Yadav; Ramji Lal

2013-01-01

259

Characterisation and detection of Pythium and Phytophthora species associated with grapevines in South Africa.  

Science.gov (United States)

Replant and decline diseases of grapevines not only cause quantitative and qualitative yield losses, but also results in extra costs when vineyards have to be replanted. This study investigated the role of Pythium and Phytophthora in the decline syndrome in South Africa by determining the (i) speci...

260

Pythium root rot of common bean: biology and control methods. A review  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Pythium root rot constitutes a highly damaging constraint on the common bean, Phaseolus vulgaris L., grown in several areas of Eastern and Central Africa. Here, this food legume is cultivated intensively under poor conditions of crop rotation due to the exiguity of the land in the region. Yield loss...

Nzungize, JR.; Lyumugabe, F.; Busogoro, JP.; Baudoin, JP.

 
 
 
 
261

Taxonomy, DNA barcoding and phylogeny of three new species of Pythium from Canada  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Three new species of Pythium, namely, P. oopapillum, P. emineosum and P. camurandrum are presented in this paper based on morphological descriptions and molecular phylogenetic characterisation. These new species were isolated from various ecological regions in Canada. They have unique morphological ...

Bala, K.; Robideau, G.P.; Désaulniers, N.; de Cock, A.W.A.M.; Lévesque, C.A.

262

Pythium root rot of common bean : biology and control methods. A review  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Pythium root rot constitutes a highly damaging constraint on the common bean, Phaseolus vulgaris L., grown in several areas of Eastern and Central Africa. Here, this food legume is cultivated intensively under poor conditions of crop rotation due to the exiguity of the land in the region. Yield loss...

Nzungize, J.R.; Lyumugabe, F.; Busogoro, J.-P.; Baudoin, Jean-Pierre

263

Development of a Species-Specific Probe for Pythium insidiosum and the Diagnosis of Pythiosis  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Pythium insidiosum, the only species in the genus that infects mammals, is the etiological agent of pythiosis, a granulomatous disease characterized by cutaneous and subcutaneous lesions and vascular diseases. Accurate diagnosis of pythiosis and identification of its causal agent are often inconsist...

Schurko, Andrew M.; Mendoza, Leonel; de Cock, Arthur W. A. M.; Bedard, James E. J.; Klassen, Glen R.

264

Cytological Effects of Cellulases in the Parasitism of Phytophthora parasitica by Pythium oligandrum  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The ubiquitous oomycete Pythium oligandrum is a potential biocontrol agent for use against a wide range of pathogenic fungi and an inducer of plant disease resistance. The ability of P. oligandrum to compete with root pathogens for saprophytic colonization of substrates may be critical for pathogen ...

Picard, Karine; Tirilly, Yves; Benhamou, Nicole

265

Pathogenicity and virulence of Pythium species obtained from forest nursery soils on Douglas-fir seedlings  

Science.gov (United States)

Pythium species are common soilborne oomycetes that occur in forest nursery soils in the Pacific Northwest (PNW) region of the United States. Numerous species have been described. However, with the exception of P. aphanidermatum, P. irregulare, P.mamillatum, and P. ultimum, little is known about the...

266

Geographic distribution of Rhizoctonia and Pythium species in soils throughout eastern Washington.  

Science.gov (United States)

Rhizoctonia and Pythium species cause substantial reductions in yield in eastern Washington. Both organisms are common in agricultural soils; however, the specific species or anastomosis group (AG) present can vary from site to site. Due to a wide range in virulence among these different groups, t...

268

COMPOSITION AND DISTRIBUTION OF PYTHIUM COMMUNITIES FROM WHEAT FIELDS IN EASTERN WASHINGTON STATE.  

Science.gov (United States)

Pythium spp. were isolated from the soil of 80 wheat fields in eastern Washington in summer 2000, from an area encompassing approximately 27,000 km2. These sites covered a range of soil textures (course to fine silty loess), average annual precipitation (200 to 600 mm) and average annual temperature...

269

Identification of Emerging Human-Pathogenic Pythium insidiosum by Serological and Molecular Assay-Based Methods  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Pythium insidiosum is a pathogen that causes disease in both animals and humans. Human infection is rare; however, when it does occur, most patients, especially those having underlying hemoglobinopathy syndromes, such as thalassemia, exhibit a severe form. We identified four isolates of P. insidiosu...

Vanittanakom, Nongnuch; Supabandhu, Jitwadee; Khamwan, Chantana; Praparattanapan, Jutarut; Thirach, Sophit; Prasertwitayakij, Narawudt

270

Influence of Pythium oligandrum Biocontrol on Fungal and Oomycete Population Dynamics in the Rhizosphere?  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Fungal and oomycete populations and their dynamics were investigated following the introduction of the biocontrol agent Pythium oligandrum into the rhizosphere of tomato plants grown in soilless culture. Three strains of P. oligandrum were selected on the basis of their ability to form oospores (res...

Vallance, Jessica; Le Floch, Gaétan; Déniel, Franck; Barbier, Georges; Lévesque, C. André; Rey, Patrice

271

Larval Bradysia impatiens (Diptera: Sciaridae) potential for vectoring Pythium root rot pathogens.  

UK PubMed Central (United Kingdom)

A series of laboratory experiments were conducted to investigate the capacity of Bradysia impatiens (Johannsen) larvae to ingest propagules from two strains each of Pythium aphanidermatum (Edson) Fitzp. and P. ultimum Trow and transmit the pathogens to healthy geranium seedlings on a filter-paper substrate in petri dishes. The capacity of fungus gnat larvae to transmit P. aphanidermatum to seedlings rooted in a commercial peat-based potting mix and germination of Pythium oospores and hyphal swellings before and after passage through the guts of larval fungus gnats were also examined. Assays revealed that Pythium spp. transmission by larval fungus gnats varied greatly with the assay substrate and also with the number and nature of ingested propagules. Transmission was highest (65%) in the petri dish assays testing larvae fed P. aphanidermatum K-13, a strain that produced abundant oospores. Transmission of strain K-13 was much lower (<6%) in plug cells with potting mix. Larvae were less efficient at vectoring P. ultimum strain PSN-1, which produced few oospores, and no transmission was observed with two non-oospore-producing strains: P. aphanidermatum Pa58 and P. ultimum P4. Passage of P. aphanidermatum K-13 through larval guts significantly increased oospore germination. However, decreased germination of hyphal swellings was observed following larval gut passage for strains of P. ultimum. These results expand previous studies suggesting that larval fungus gnats may vector Pythium spp.

Braun SE; Sanderson JP; Wraight SP

2012-03-01

272

Incidence and spatial distribution of Rhizoctonia and Pythium species determined with real-time PCR  

Science.gov (United States)

Populations of Rhizoctonia and Pythium are diverse in eastern Washington, with multiple species/anastomosis groups present throughout the region and within individual fields. Recent evidence suggests that species composition may be influenced by crop rotation. The Cook Agronomy Farm near Pullman, WA...

273

Pythium species Associated with Forest Tree Nurseries of Oregon and Washington  

Science.gov (United States)

Pythium species are one of several pathogen genera responsible for damping off of conifer seedlings in forest tree nurseries. Species identification has been traditionally based on morphology. However, DNA-based identification methods may allow more accurate identification of species associated wi...

274

Transstadial transmission of Pythium in Bradysia impatiens and lack of adult vectoring capacity  

Science.gov (United States)

Fungus gnats have been shown to transmit a variety of plant pathogenic fungi that produce aerial dispersal stages. However, few studies have examined potential interactions between fungus gnats and oomycetes, including Pythium spp. A series of laboratory experiments were conducted to determine if ...

275

Molecular diagnosis of subcutaneous Pythium insidiosum infection by use of PCR screening and DNA sequencing.  

Science.gov (United States)

Pythium insidiosum is an emerging human pathogen classified among brown algae and diatoms that can cause significant morbidity and mortality in otherwise healthy individuals. Here we describe a pediatric patient with pythiosis acquired in the southern United States, diagnosed by molecular screening and DNA sequencing of internal transcribed spacer region 1. PMID:22205808

Salipante, Stephen J; Hoogestraat, Daniel R; SenGupta, Dhruba J; Murphey, Donald; Panayides, Kyriacos; Hamilton, Emma; Castañeda-Sánchez, Irene; Kennedy, Jason; Monsaas, Peter W; Mendoza, Leonel; Stephens, Karen; Dunn, James J; Cookson, Brad T

2012-01-11

276

Molecular diagnosis of subcutaneous Pythium insidiosum infection by use of PCR screening and DNA sequencing.  

UK PubMed Central (United Kingdom)

Pythium insidiosum is an emerging human pathogen classified among brown algae and diatoms that can cause significant morbidity and mortality in otherwise healthy individuals. Here we describe a pediatric patient with pythiosis acquired in the southern United States, diagnosed by molecular screening and DNA sequencing of internal transcribed spacer region 1.

Salipante SJ; Hoogestraat DR; SenGupta DJ; Murphey D; Panayides K; Hamilton E; Castañeda-Sánchez I; Kennedy J; Monsaas PW; Mendoza L; Stephens K; Dunn JJ; Cookson BT

2012-04-01

277

Nonfeed application of rendered animal proteins for microbial production of eicosapentaenoic acid by the fungus Pythium irregulare.  

Science.gov (United States)

Rendered animal proteins are well suited for animal nutrition applications, but the market is maturing, and there is a need to develop new uses for these products. The objective of this study is to explore the possibility of using animal proteins as a nutrient source for microbial production of omega-3 polyunsaturated fatty acids by the microalga Schizochytrium limacinum and the fungus Pythium irregulare. To be absorbed by the microorganisms, the proteins needed to be hydrolyzed into small peptides and free amino acids. The utility of the protein hydrolysates for microorganisms depended on the hydrolysis method used and the type of microorganism. The enzymatic hydrolysates supported better cell growth performance than the alkali hydrolysates did. P. irregulare displayed better overall growth performance on the experimental hydrolysates compared to S. limacinum. When P. irregulare was grown in medium containing 10 g/L enzymatic hydrolysate derived from meat and bone meal or feather meal, the performance of cell growth, lipid synthesis, and omega-3 fatty acid production was comparable to the that of culture using commercial yeast extract. The fungal biomass derived from the animal proteins had 26-29% lipid, 32-34% protein, 34-39% carbohydrate, and <2% ash content. The results show that it is possible to develop a nonfeed application for rendered animal protein by hydrolysis of the protein and feeding to industrial microorganisms which can produce omega-3 fatty acids for making omega-3-fortified foods or feeds. PMID:22010831

Liang, Yi; Garcia, Rafael A; Piazza, George J; Wen, Zhiyou

2011-11-02

278

Nonfeed application of rendered animal proteins for microbial production of eicosapentaenoic acid by the fungus Pythium irregulare.  

UK PubMed Central (United Kingdom)

Rendered animal proteins are well suited for animal nutrition applications, but the market is maturing, and there is a need to develop new uses for these products. The objective of this study is to explore the possibility of using animal proteins as a nutrient source for microbial production of omega-3 polyunsaturated fatty acids by the microalga Schizochytrium limacinum and the fungus Pythium irregulare. To be absorbed by the microorganisms, the proteins needed to be hydrolyzed into small peptides and free amino acids. The utility of the protein hydrolysates for microorganisms depended on the hydrolysis method used and the type of microorganism. The enzymatic hydrolysates supported better cell growth performance than the alkali hydrolysates did. P. irregulare displayed better overall growth performance on the experimental hydrolysates compared to S. limacinum. When P. irregulare was grown in medium containing 10 g/L enzymatic hydrolysate derived from meat and bone meal or feather meal, the performance of cell growth, lipid synthesis, and omega-3 fatty acid production was comparable to the that of culture using commercial yeast extract. The fungal biomass derived from the animal proteins had 26-29% lipid, 32-34% protein, 34-39% carbohydrate, and <2% ash content. The results show that it is possible to develop a nonfeed application for rendered animal protein by hydrolysis of the protein and feeding to industrial microorganisms which can produce omega-3 fatty acids for making omega-3-fortified foods or feeds.

Liang Y; Garcia RA; Piazza GJ; Wen Z

2011-11-01

279

Efficacy of Antifungal Metabolites of Bacillus spp. for Controlling Tomato Damping-off Caused by Pythium aphanidermatum  

Directory of Open Access Journals (Sweden)

Full Text Available A total of 4 strains of bacteria were isolated from the leaf surface of the rambutan using a tissue transplanting technique. They were characterized, by a dual culture test, for their efficacy to inhibit mycelial growth of Pythium aphanidermatum, a causal agent of the damping-off on tomato. All 4 strains significantly inhibited mycelial growth of P. aphanidermatum on potato dextrose agar (PDA) at room temperature (27 °C). B-NST-02 and B-NST-03 gave values of inhibition of 62.0 % and   57.5 %, respectively. All strains were identified as Bacillus spp. Antifungal metabolites extracted from all 4 strains were tested at 1,000 mg/l. Tomato seedlings treated in the laboratory with metabolites from B-NST-03 and B-NST-02 showed germination of 85.5 % and 82.0 %, respectively. Under glasshouse conditions, seedling treated with metabolites from B-NST-03 and B-NST-02 provided seed germination rates were 92.5 % and 92.0 %, respectively, while the controls treated with either sterile water or 2 % methanol had only 28.0 % and 26.5 % seed germination rates, respectively. In P. aphanidermatum viability test, mycelia of P. aphanidermatum treated with antifungal metabolites from 4 strains of Bacillus spp. showed no visible growth, while the control with sterile water or 2 % methanol, mycelia of P. aphanidermatum rapidly grew and covered the whole surface of the PDA in the Petri dish within 5 days.

Warin INTANA; Prakong YENJIT; Taksin SUWANNO; Supalak SATTASAKULCHAI; Manoon SUWANNO; Chiradej CHAMSWARNG

2008-01-01

280

Cultivation of Trichosporon mycotoxinivorans in sugarcane bagasse hemicellulosic hydrolyzate  

Scientific Electronic Library Online (English)

Full Text Available Abstract in english Background: The yeast strain IB09 was isolated from the gut of Calosoma sp. (Carabidae, Coleoptera, Insecta) that were collected in the central Amazon rainforest. First, tolerance of the strain to ethanol and heat was tested. Then, IB09 was cultivated in a medium using sugarcane bagasse hemicellulosic hydrolyzate as a carbon source, and cell growth (OD600), specific growth rate (µMAX, h-1), biomass yield (Y B, g.g-1) and relative sugar consumption (RSC, %) were evaluated (more) . Taxonomic identification was determined by sequencing the ITS1 region of IB09 and comparing it to sequences obtained from the GenBank database (NCBI). Results: IB09 showed both ethanol tolerance and thermotolerance. Relative sugar consumption indicated that IB09 was able to perform saccharification of sugarcane bagasse hemicellulosic hydrolyzate, increasing the total reducing sugar concentration by approximately 50%. The ?MAX value obtained was 0,20, indicating that cell growth was slow under the assessed conditions. Biomass yield was 0,701 g per g of consumed sugar, which is relatively high when compared with other findings in the literature. After 120 hrs of cultivation, 80,1% of total reducing sugar had been consumed. Sequencing of the ITS1 region identified IB09 as Trichosporon mycotoxinivorans. Conclusion: This is the first report to document this species in the central Amazon rainforest at this host. Trichosporon mycotoxinivorans has great biotechnological potential for use in the saccharification of sugarcane bagasse hemicellulosic hydrolyzate and for biomass production with this substrate as carbon source.

Matos, Ítalo Thiago Silveira Rocha; Cassa-Barbosa, Luciana Araújo; Neto, Pedro Queiroz Costa; Filho, Spartaco Astolfi

2012-01-01

 
 
 
 
281

Extracellular hydrolysis of starch in sugarcane cell suspensions.  

Science.gov (United States)

Evidence is presented for the increased excretion of amylolytic enzymes into a sugarcane cell culture medium when starch was substituted for sucrose as an energy source. The excretion was further enhanced by the inclusion of 1 mum gibberellic acid in the nutrient medium. The growth rate of the cells increased after they became adapted to starch relative to cells grown on sucrose, but the rate of amylolytic enzyme excretion remained unaltered. Amylolytic enzymes in the medium included alpha-amylase but the identity of one or more other enzymes related to starch hydrolysis remains in doubt. PMID:16657831

Maretzki, A; Dela Cruz, A; Nickell, L G

1971-11-01

282

Extracellular hydrolysis of starch in sugarcane cell suspensions.  

UK PubMed Central (United Kingdom)

Evidence is presented for the increased excretion of amylolytic enzymes into a sugarcane cell culture medium when starch was substituted for sucrose as an energy source. The excretion was further enhanced by the inclusion of 1 mum gibberellic acid in the nutrient medium. The growth rate of the cells increased after they became adapted to starch relative to cells grown on sucrose, but the rate of amylolytic enzyme excretion remained unaltered. Amylolytic enzymes in the medium included alpha-amylase but the identity of one or more other enzymes related to starch hydrolysis remains in doubt.

Maretzki A; Dela Cruz A; Nickell LG

1971-11-01

283

Yield and quality of induced mutants in sugarcane  

International Nuclear Information System (INIS)

Twenty-one near-normal and 4 drastic mutants isolated from mutagen-treated (X-rays, gamma rays and chemical mutagens) sugarcane variety 'Co 419' were tested for yield and juice quality. Mutants '368. and '419/1' had higher yield of cane and higher commercial cane sugar than 'Co 419'. Several mutants, especially the drastic mutants, had higher percentage of sucrose than 'Co 419'. The types with higher percentage of sucrose occurred much more frequently than the higher-yielding ones, indicating more frequent occurrence of disturbances in growth, resulting in diversion of more sucrose to storage than to the apical meristem. (auth.)

1981-01-01

284

Surface motility in Pseudomonas sp DSS73 is required for efficient biological containment of the root-pathogenic microfungi Rhizoctonia solani and Pythium ultimum  

DEFF Research Database (Denmark)

Pseudomonas sp. DSS73 was isolated from the rhizoplane of sugar beet seedlings. This strain exhibits antagonism towards the root-pathogenic microfungi Pythium ultimum and Rhizoctonia solani. Production of the cyclic lipopeptide amphisin in combination with expression of flagella enables the growing bacterial culture to move readily over the surface of laboratory media. Amphisin is a new member of a group of dual-functioning compounds such as tensin, viscosin and viscosinamid that display both biosurfactant and antifungal properties. The ability of DSS73 to efficiently contain root-pathogenic microfungi is shown to arise from amphisin-dependent surface translocation and growth by which the bacterium can lay siege to the fungi. The synergistic effects of surface motility and synthesis of a battery of antifungal compounds efficiently contain and terminate growth of the microfungi.

Andersen, Jens Bo; Koch, Birgit

2003-01-01

285

Pythium polare, a new heterothallic oomycete causing brown discolouration of Sanionia uncinata in the Arctic and Antarctic.  

UK PubMed Central (United Kingdom)

Pythium polare sp. nov. is a new heterothallic oomycete species isolated from fresh water and moss from various locations in both the Arctic and Antarctic. This water mould is able to infect stems and leaves of Sanionia moss (Sanionia uncinata). Pythium polare causes brown discolouration in in vitro inoculation tests at 5 °C after 5 weeks of inoculation. It is characterized by globose sporangia with various lengths of discharge tubes releasing zoospores and aplerotic oospores with usually one to five antheridia. The sexual structures are only produced in a dual culture of antheridial and oogonial isolates. Phylogenetic analysis, based on ITS sequencing, places all isolated strains of P. polare in a unique new clade, hence it is considered a novel species. Pythium canariense and Pythium violae are the most closely related species of P. polare based both on morphology and the phylogenetic analysis.

Tojo M; van West P; Hoshino T; Kida K; Fujii H; Hakoda A; Kawaguchi Y; Mühlhauser HA; Van Den Berg AH; Küpper FC; Herrero ML; Klemsdal SS; Tronsmo AM; Kanda H

2012-07-01

286

The Purification of Cellulase and Exo-Laminaranase and Their Role in the Formation of Pythium Sp. 'Protoplasts'.  

Science.gov (United States)

A cellulase and a laminaranase have been purified from a Streptomyces lytic enzyme complex. Lipase and protease were separated from glucanases. A combination of the purified glucanases produced 'protoplasts' from Pythium sp. PRL 2142. Lipase was shown to ...

J. H. Sietsma D. E. Eveleigh R. H. Haskins

1967-01-01

287

Pythium polare, a new heterothallic oomycete causing brown discolouration of Sanionia uncinata in the Arctic and Antarctic.  

Science.gov (United States)

Pythium polare sp. nov. is a new heterothallic oomycete species isolated from fresh water and moss from various locations in both the Arctic and Antarctic. This water mould is able to infect stems and leaves of Sanionia moss (Sanionia uncinata). Pythium polare causes brown discolouration in in vitro inoculation tests at 5 °C after 5 weeks of inoculation. It is characterized by globose sporangia with various lengths of discharge tubes releasing zoospores and aplerotic oospores with usually one to five antheridia. The sexual structures are only produced in a dual culture of antheridial and oogonial isolates. Phylogenetic analysis, based on ITS sequencing, places all isolated strains of P. polare in a unique new clade, hence it is considered a novel species. Pythium canariense and Pythium violae are the most closely related species of P. polare based both on morphology and the phylogenetic analysis. PMID:22749162

Tojo, Motoaki; van West, Pieter; Hoshino, Tamotsu; Kida, Kenichi; Fujii, Hirokazu; Hakoda, Akiho; Kawaguchi, Yuki; Mühlhauser, Hermann A; Van Den Berg, Albert H; Küpper, Frithjof C; Herrero, María L; Klemsdal, Sonja S; Tronsmo, Anne Marte; Kanda, Hiroshi

2012-04-27

288

Lifecycle assessment of fuel ethanol from sugarcane in Brazil  

DEFF Research Database (Denmark)

This paper presents the lifecycle assessment (LCA) of fuel ethanol, as 100% of the vehicle fuel, from sugarcane in Brazil. The functional unit is 10,000 km run in an urban area by a car with a 1,600-cm(3) engine running on fuel hydrated ethanol, and the resulting reference flow is 1,000 kg of ethanol. The product system includes agricultural and industrial activities, distribution, cogeneration of electricity and steam, ethanol use during car driving, and industrial by-products recycling to irrigate sugarcane fields. The use of sugarcane by the ethanol agribusiness is one of the foremost financial resources for the economy of the Brazilian rural area, which occupies extensive areas and provides far-reaching potentials for renewable fuel production. But, there are environmental impacts during the fuel ethanol lifecycle, which this paper intents to analyze, including addressing the main activities responsible for such impacts and indicating some suggestions to minimize the impacts. This study is classified as an applied quantitative research, and the technical procedure to achieve the exploratory goal is based on bibliographic revision, documental research, primary data collection, and study cases at sugarcane farms and fuel ethanol industries in the northeast of SA o pound Paulo State, Brazil. The methodological structure for this LCA study is in agreement with the International Standardization Organization, and the method used is the Environmental Design of Industrial Products. The lifecycle impact assessment (LCIA) covers the following emission-related impact categories: global warming, ozone formation, acidification, nutrient enrichment, ecotoxicity, and human toxicity. The results of the fuel ethanol LCI demonstrate that even though alcohol is considered a renewable fuel because it comes from biomass (sugarcane), it uses a high quantity and diversity of nonrenewable resources over its lifecycle. The input of renewable resources is also high mainly because of the water consumption in the industrial phases, due to the sugarcane washing process. During the lifecycle of alcohol, there is a surplus of electric energy due to the cogeneration activity. Another focus point is the quantity of emissions to the atmosphere and the diversity of the substances emitted. Harvesting is the unit process that contributes most to global warming. For photochemical ozone formation, harvesting is also the activity with the strongest contributions due to the burning in harvesting and the emissions from using diesel fuel. The acidification impact potential is mostly due to the NOx emitted by the combustion of ethanol during use, on account of the sulfuric acid use in the industrial process and because of the NOx emitted by the burning in harvesting. The main consequence of the intensive use of fertilizers to the field is the high nutrient enrichment impact potential associated with this activity. The main contributions to the ecotoxicity impact potential come from chemical applications during crop growth. The activity that presents the highest impact potential for human toxicity (HT) via air and via soil is harvesting. Via water, HT potential is high in harvesting due to lubricant use on the machines. The normalization results indicate that nutrient enrichment, acidification, and human toxicity via air and via water are the most significant impact potentials for the lifecycle of fuel ethanol. The fuel ethanol lifecycle contributes negatively to all the impact potentials analyzed: global warming, ozone formation, acidification, nutrient enrichment, ecotoxicity, and human toxicity. Concerning energy consumption, it consumes less energy than its own production largely because of the electricity cogeneration system, but this process is highly dependent on water. The main causes for the biggest impact potential indicated by the normalization is the nutrient application, the burning in harvesting and the use of diesel fuel. The recommendations for the ethanol lifecycle are: harvesting the sugarcane without burning; more environmentally benign agric

Ometto, A. R.; Hauschild, Michael Zwicky

2009-01-01

289

Selection of rhizobacteria for the control of Pythium ultimum and Aphanomyces cochlioides on sugar-beet seedlings.  

UK PubMed Central (United Kingdom)

Approximately 400 bacterial isolates from the roots of field-grown sugar-beet seedlings were examined for their ability to inhibit the growth of Pythium ultimum and Aphanomyces cochlioides in culture and to suppress disease caused by these pathogens when applied to pelleted sugar-beet seed in artificially infested soil. Biocontrol potential was assessed in controlled environments, under optimal conditions for disease development and expression. A large proportion of the rhizobacteria isolates were antagonistic to the fungi in culture, but only c. 1% were effective biocontrol agents. Isolates that inhibited growth in vitro were, in general, active against both fungal species, whereas in vivo, isolates that most suppressed P. ultimum were different from those most effective against A. cochlioides. Over all isolates with both pathogens, there was no correlation between the degree of inhibition in culture and the extent of disease suppression. Effective biocontrol isolates significantly improved seedling emergence and the proportion of healthy seedlings compared with untreated seed. However, under the high disease pressure generated in these experiments, the level of protection fell short of that achieved with the fungicides currently in use on sugar-beet seed.

Williams GE; Asher MJC

1996-08-01

290

In vitro antimicrobial activity of volatile organic compounds from Muscodor crispans against the pathogenic oomycete Pythium insidiosum.  

UK PubMed Central (United Kingdom)

Pythium insidiosum is an oomycete capable of causing a life-threatening disease in humans, called pythiosis. Conventional antifungal drugs are ineffective against P. insidiosum infection. A synthetic mixture of the volatile organic compounds (VOCs) from the endophytic fungus Muscodor crispans strain B23 demonstrates antimicrobial effects against a broad range of human and plant pathogens, including fungi, bacteria, and oomycetes. We studied the in vitro effects of B23 VOCs against 25 human, 1 animal, and 4 environmental isolates of P. insidiosum, compared with a no-drug control. The B23 synthetic mixture, at amounts as low as 2.5 microl, significantly reduced growth of all P. insidiosum isolates by at least 80%. The inhibitory effect of the B23 VOCs was dose-dependent. The growth of all isolates was completely inhibited by a dose of 10.0 microl of B23 VOCs, and all isolates were killed by a dose of 20.0 microl. Synthetic B23 VOCs of M. crispans had inhibitory and lethal effects against all P. insidiosum isolates tested. Further studies are needed to evaluate this mixture for treatment of pythiosis.

Krajaejun T; Lowhnoo T; Yingyong W; Rujirawat T; Fucharoen S; Strobel GA

2012-11-01

291

In vitro antimicrobial activity of volatile organic compounds from Muscodor crispans against the pathogenic oomycete Pythium insidiosum.  

Science.gov (United States)

Pythium insidiosum is an oomycete capable of causing a life-threatening disease in humans, called pythiosis. Conventional antifungal drugs are ineffective against P. insidiosum infection. A synthetic mixture of the volatile organic compounds (VOCs) from the endophytic fungus Muscodor crispans strain B23 demonstrates antimicrobial effects against a broad range of human and plant pathogens, including fungi, bacteria, and oomycetes. We studied the in vitro effects of B23 VOCs against 25 human, 1 animal, and 4 environmental isolates of P. insidiosum, compared with a no-drug control. The B23 synthetic mixture, at amounts as low as 2.5 microl, significantly reduced growth of all P. insidiosum isolates by at least 80%. The inhibitory effect of the B23 VOCs was dose-dependent. The growth of all isolates was completely inhibited by a dose of 10.0 microl of B23 VOCs, and all isolates were killed by a dose of 20.0 microl. Synthetic B23 VOCs of M. crispans had inhibitory and lethal effects against all P. insidiosum isolates tested. Further studies are needed to evaluate this mixture for treatment of pythiosis. PMID:23413712

Krajaejun, Theerapong; Lowhnoo, Tassanee; Yingyong, Wanta; Rujirawat, Thidarat; Fucharoen, Suthat; Strobel, Gary A

2012-11-01

292

Morphological Characters of Some Exotic Sugarcane Varieties  

Directory of Open Access Journals (Sweden)

Full Text Available Six exotic varieties of sugarcane (CP84-1198, CP85-1491, CP88-1165, CP77-400, CP89-846, TCP86-3368) planted at the National Agricultural Research Centre during 1998-99 were described for their morphological characters. All the varieties greatly varied in different characters. Mean leaf length, number of green leaves and width of leaf lamina/blade was different in different varieties. These varieties also differed in leaf sheath colour, carriage, and other leaf characters. Shape of the dewlap, its size and colour, shape of ligule and ligular process or auricle was also different. All the varieties varied in diameter of the stalks, colour of the stalks, shape of internode, bud groove characters, width and colour of growth ring, width and colour of root zone and wax band characters. Ivory markings were present on stalks of all the varieties. All the varieties were similar in bud size, but different in shapes of the bud, some having flanges and some without flanges. Position of the germ pore on the bud was also different in all the varieties.

Maqbool Akhtar; Nosheen Noor Elahi; M. Ashraf

2001-01-01

293

Flood Duration and Time of Flood Onset Effects on Recently Planted Sugarcane  

UK PubMed Central (United Kingdom)

Periodically flooding sugarcane (Saccharum spp.) by delaying drainage after rain in the Everglades Agricultural Area (EAA) of Florida improves soil conservation and reduces P discharge to the Everglades, but farmers are concerned that flooding recently planted or recently ratooned sugarcane reduces yields. The purpose of this study was to determine the effects of time of flood onset and flood duration on stalk, leaf, and root biomass accretion of two recently planted (plant height ?9 cm) sugarcane cultivars. In three pot experiments, flood durations ranged from 0 to 6 wk and flood onsets were after 2 or 4 wk at a 30-cm water-table depth. Five treatments also had a second flood onset during the final 4 or 6 wk of each experiment. Increased flood durations often resulted in declines in biomass explained by linear or quadratic models. Compared with ‘CP 89-2143,’ leaf and stalk biomasses of ‘CP 96-1252’ were more tolerant of increasing flood durations, but the opposite was true for root biomass. Sugarcane leaf biomass was reduced more by flood onset following 2 rather than 4 wk at a 30-cm water-table depth, but stalk and root biomasses were similarly reduced by both flood onsets. Although previous results have indicated that well-established sugarcane in its grand-growth phase is tolerant to periodic flooding, our results suggest that the biomass of younger (recently planted) sugarcane is increasingly reduced by flood durations of 0 to 6 wk and that flood onsets after 2 or 4 wk at a 30-cm water-table depth are similarly detrimental.

Glaz B; Lingle SE

2012-05-01

294

The sustainability of ethanol production from sugarcane  

Energy Technology Data Exchange (ETDEWEB)

The rapid expansion of ethanol production from sugarcane in Brazil has raised a number of questions regarding its negative consequences and sustainability. Positive impacts are the elimination of lead compounds from gasoline and the reduction of noxious emissions. There is also the reduction of CO{sub 2} emissions, since sugarcane ethanol requires only a small amount of fossil fuels for its production, being thus a renewable fuel. These positive impacts are particularly noticeable in the air quality improvement of metropolitan areas but also in rural areas where mechanized harvesting of green cane is being introduced, eliminating the burning of sugarcane. Negative impacts such as future large-scale ethanol production from sugarcane might lead to the destruction or damage of high-biodiversity areas, deforestation, degradation or damaging of soils through the use of chemicals and soil decarbonization, water resources contamination or depletion, competition between food and fuel production decreasing food security and a worsening of labor conditions on the fields. These questions are discussed here, with the purpose of clarifying the sustainability aspects of ethanol production from sugarcane mainly in Sao Paulo State, where more than 60% of Brazil's sugarcane plantations are located and are responsible for 62% of ethanol production. (author)

Goldemberg, Jose; Coelho, Suani Teixeira; Guardabassi, Patricia [CENBIO - The Brazilian Reference Center on Biomass, IEE - Institute of Eletrotechnics and Energy, USP - University of Sao Paulo, Sao Paulo (Brazil)

2008-06-15

295

The sustainability of ethanol production from sugarcane  

International Nuclear Information System (INIS)

The rapid expansion of ethanol production from sugarcane in Brazil has raised a number of questions regarding its negative consequences and sustainability. Positive impacts are the elimination of lead compounds from gasoline and the reduction of noxious emissions. There is also the reduction of CO2 emissions, since sugarcane ethanol requires only a small amount of fossil fuels for its production, being thus a renewable fuel. These positive impacts are particularly noticeable in the air quality improvement of metropolitan areas but also in rural areas where mechanized harvesting of green cane is being introduced, eliminating the burning of sugarcane. Negative impacts such as future large-scale ethanol production from sugarcane might lead to the destruction or damage of high-biodiversity areas, deforestation, degradation or damaging of soils through the use of chemicals and soil decarbonization, water resources contamination or depletion, competition between food and fuel production decreasing food security and a worsening of labor conditions on the fields. These questions are discussed here, with the purpose of clarifying the sustainability aspects of ethanol production from sugarcane mainly in Sao Paulo State, where more than 60% of Brazil's sugarcane plantations are located and are responsible for 62% of ethanol production.

2008-01-01

296

Power plant perspectives for sugarcane mills  

Energy Technology Data Exchange (ETDEWEB)

Biomass, integral to life, is one of the main energy sources that modern technologies could widely develop, overcoming inefficient and pollutant uses. The sugarcane bagasse is one of the more abundant biomass. Moreover, the fluctuating sugar and energy prices force the sugarcane companies to implement improved power plants. Thanks to a multiyear collaboration between University of Rome and University of Piura and Chiclayo, this paper investigates, starting from the real data of an old sugarcane plant, the energy efficiency of the plant. Furthermore, it explores possible improvements as higher temperature and pressure Rankine cycles and innovative configurations based on gasifier plus hot gas conditioning and gas turbine or molten carbonate fuel cells. Even if the process of sugar extraction from sugarcane and the relative Rankine cycles power plants are well documented in literature, this paper shows that innovative power plant configurations can increase the bagasse-based cogeneration potential. Sugarcane companies can become electricity producers, having convenience in the use of sugarcane leaves and trash (when it is feasible). The worldwide implementation of advanced power plants, answering to a market competition, will improve significantly the renewable electricity produced, reducing CO{sub 2} emissions, and increasing economic and social benefits. (author)

Bocci, E.; Di Carlo, A. [University of Rome ' ' La Sapienza' ' , Department of Mechanics and Aeronautics, Via Eudossiana 18, 00184 Rome (Italy); Marcelo, D. [University of Piura, Department of Energy, Av. Ramon Mugica, 131 Piura (Peru)

2009-05-15

297

Sugarcane vinasse: Environmental implications of its use.  

UK PubMed Central (United Kingdom)

The inadequate and indiscriminate disposal of sugarcane vinasse in soils and water bodies has received much attention since decades ago, due to environmental problems associated to this practice. Vinasse is the final by-product of the biomass distillation, mainly for the production of ethanol, from sugar crops (beet and sugarcane), starch crops (corn, wheat, rice, and cassava), or cellulosic material (harvesting crop residues, sugarcane bagasse, and wood). Because of the large quantities of vinasse produced, alternative treatments and uses have been developed, such as recycling of vinasse in fermentation, fertirrigation, concentration by evaporation, and yeast and energy production. This review was aimed at examining the available data on the subject as a contribution to update the information on sugarcane vinasse, from its characteristics and chemical composition to alternatives uses in Brazil: fertirrigation, concentration by evaporation, energy production; the effects on soil physical, chemical and biological properties; its influence on seed germination, its use as biostimulant and environmental contaminant. The low pH, electric conductivity, and chemical elements present in sugarcane vinasse may cause changes in the chemical and physical-chemical properties of soils, rivers, and lakes with frequent discharges over a long period of time, and also have adverse effects on agricultural soils and biota in general. Thus, new studies and green methods need to be developed aiming at sugarcane vinasse recycling and disposal.

Christofoletti CA; Escher JP; Correia JE; Marinho JF; Fontanetti CS

2013-09-01

298

The influence of Aspergillus niger transcription factors AraR and XlnR in the gene expression during growth in D-xylose, L-arabinose and steam-exploded sugarcane bagasse.  

UK PubMed Central (United Kingdom)

The interest in the conversion of plant biomass to renewable fuels such as bioethanol has led to an increased investigation into the processes regulating biomass saccharification. The filamentous fungus Aspergillus niger is an important microorganism capable of producing a wide variety of plant biomass degrading enzymes. In A. niger the transcriptional activator XlnR and its close homolog, AraR, controls the main (hemi-)cellulolytic system responsible for plant polysaccharide degradation. Sugarcane is used worldwide as a feedstock for sugar and ethanol production, while the lignocellulosic residual bagasse can be used in different industrial applications, including ethanol production. The use of pentose sugars from hemicelluloses represents an opportunity to further increase production efficiencies. In the present study, we describe a global gene expression analysis of A. niger XlnR- and AraR-deficient mutant strains, grown on a D-xylose/L-arabinose monosaccharide mixture and steam-exploded sugarcane bagasse. Different gene sets of CAZy enzymes and sugar transporters were shown to be individually or dually regulated by XlnR and AraR, with XlnR appearing to be the major regulator on complex polysaccharides. Our study contributes to understanding of the complex regulatory mechanisms responsible for plant polysaccharide-degrading gene expression, and opens new possibilities for the engineering of fungi able to produce more efficient enzymatic cocktails to be used in biofuel production.

de Souza WR; Maitan-Alfenas GP; de Gouvêa PF; Brown NA; Savoldi M; Battaglia E; Goldman MH; de Vries RP; Goldman GH

2013-07-01

299

Influence of siderurgical slag about gaseous changes and production of biomass of sugarcane  

Directory of Open Access Journals (Sweden)

Full Text Available The experiment was installed in greenhouse, using one of the most representative soils of the state of Ceará, Brazil, for sugarcane crop, a Red-Yellow Argissoil. The main goal of this research was to evaluate the influence of silicon in the gas exchange and production of biomass of sugarcane cultivars in sandy loam soil. It was used a completely randomized in 5x2 factorial scheme with five silicon doses: 0; 2.5; 5.0; 10.0 and 15.0 g per pot-1 of siderurgical slag, two cultivars of sugarcane and four repetitions. The siderurgical slag (calcium and magnesium silicato) used containing 11% of soluble SiO2. It was evaluated the silicon level in the leaf, the production of dry matter of the aerial part, the relative growth rate of the plant, the water use efficiency, transpiration and conductance of the leaf. The results showed increase in concentration of Si in leaf with the application of the silicon; practically no influence in growth and physiological characteristics of the plants.Key-words: Argissoil, calcium, greenhouse, sugarcane.

Lúcio Bastos Madeiros; Andreia de Oliveira Vieira; Boanerges Freire de Aquino

2009-01-01

300

PCDD AND PCDF EMISSIONS FROM SIMULATED SUGARCANE FIELD BURNING  

Science.gov (United States)

The emissions from simulated sugarcane field burns were sampled and analyzed for polychlorinated dibenzodioxins and dibenzofurans (PCDDs and PCDFs). Sugarcane leaves from Hawaii and Florida were burned in a manner simulating the natural physical dimensions and biomass density fou...

 
 
 
 
301

Sugarcane energy use: The Cuban case  

Energy Technology Data Exchange (ETDEWEB)

This paper examines the history, methods, costs, and future prospects of Cuba's attempts to develop the energy potential of sugarcane. An overview of the main factors affecting the current sugarcane agro-industry in Cuba is provided, along with an analysis of why, despite attempts by the Cuban government to revive the country's sugarcane agro-industry, the industry continues to decline. The prevailing conditions and degree of modernization in Cuban sugar factories are evaluated. The sugar-agro industry's main production bottlenecks are studied. The fall in sugarcane yield from 57.5 ton/ha in 1991 to 22.4 ton/ha in 2005 and its relation to land use is explained. The socio-economic impact of the sugarcane agro-industry's downsizing is assessed. The governmental and quasi-governmental entities in charge of sugarcane energy use development and the country's legal framework are analyzed. The Cuban sugarcane agro-industry's opportunities in the growing international biofuels and bioenergy market are evaluated. To situate Cuba within the global bioenergy market, international best practices relating to the production and commercialization of biofuels are examined to determine the degree to which these experiences can be transferred to Cuba. The analysis of the Cuba sugar industry's biofuel potential is based on a comparative technical-economic assessment of three possible production scenarios: (1) the current situation, where only sugar is produced; (2) simultaneous production of sugar-anhydrous ethanol; and (3) production of sugar-ethanol and simultaneous generation of surplus electricity exported to a public grid. Some of the key assumptions underlying these analyses are as follows: Ethanol production and operation costs for a 7000 ton/day-sugar mill are estimated to be 0.25 and 0.23 USD/l, respectively. The influence of gasoline prices on sugar-ethanol production is also assessed. The kWh production and operation costs starting from sugarcane bagasse are estimated at 0.06 and 0.04 USD, respectively. Cuba's potential sugarcane cogeneration capacity is estimated to be 9006 GWh/year. Investment-profit analyses are offered for two scenarios: annexing a 300,000 l/day distillery to a sugar mill, and enlarging the cogeneration capacity of a 7000 ton/day mill. Added production cost/added-value analysis was carried out. The main environmental issues associated with sugarcane-based fuel production are also analyzed. (author)

Alonso-Pippo, Walfrido; Luengo, Carlos A. [Grupo Combustiveis Alternativos, DFA/IFGW/UNICAMP, CP 6165, CEP 13083-970 Campinas, Sao Paulo (Brazil); Koehlinger, John [Energy Consultant. 1322 Hepburn Ave 1, Louisville, KY 40204 (United States); Garzone, Pietro; Cornacchia, Giacinto [ENEA Trisaia Research Centre. Prot-STP. SS106 Jonica, Rotondella (Italy)

2008-06-15

302

Sugarcane energy use: The Cuban case  

International Nuclear Information System (INIS)

This paper examines the history, methods, costs, and future prospects of Cuba's attempts to develop the energy potential of sugarcane. An overview of the main factors affecting the current sugarcane agro-industry in Cuba is provided, along with an analysis of why, despite attempts by the Cuban government to revive the country's sugarcane agro-industry, the industry continues to decline. The prevailing conditions and degree of modernization in Cuban sugar factories are evaluated. The sugar-agro industry's main production bottlenecks are studied. The fall in sugarcane yield from 57.5 ton/ha in 1991 to 22.4 ton/ha in 2005 and its relation to land use is explained. The socio-economic impact of the sugarcane agro-industry's downsizing is assessed. The governmental and quasi-governmental entities in charge of sugarcane energy use development and the country's legal framework are analyzed. The Cuban sugarcane agro-industry's opportunities in the growing international biofuels and bioenergy market are evaluated. To situate Cuba within the global bioenergy market, international best practices relating to the production and commercialization of biofuels are examined to determine the degree to which these experiences can be transferred to Cuba. The analysis of the Cuba sugar industry's biofuel potential is based on a comparative technical-economic assessment of three possible production scenarios: (1) the current situation, where only sugar is produced; (2) simultaneous production of sugar-anhydrous ethanol; and (3) production of sugar-ethanol and simultaneous generation of surplus electricity exported to a public grid. Some of the key assumptions underlying these analyses are as follows: Ethanol production and operation costs for a 7000 ton/day-sugar mill are estimated to be 0.25 and 0.23 USD/l, respectively. The influence of gasoline prices on sugar-ethanol production is also assessed. The kWh production and operation costs starting from sugarcane bagasse are estimated at 0.06 and 0.04 USD, respectively. Cuba's potential sugarcane cogeneration capacity is estimated to be 9006 GWh/year. Investment-profit analyses are offered for two scenarios: annexing a 300,000 l/day distillery to a sugar mill, and enlarging the cogeneration capacity of a 7000 ton/day mill. Added production cost/added-value analysis was carried out. The main environmental issues associated with sugarcane-based fuel production are also analyzed.

303

Base excision repair in sugarcane  

Directory of Open Access Journals (Sweden)

Full Text Available DNA damage can be induced by a large number of physical and chemical agents from the environment as well as compounds produced by cellular metabolism. This type of damage can interfere with cellular processes such as replication and transcription, resulting in cell death and/or mutations. The low frequency of mutagenesis in cells is due to the presence of enzymatic pathways which repair damaged DNA. Several DNA repair genes (mainly from bacteria, yeasts and mammals) have been cloned and their products characterized. The high conservation, especially in eukaryotes, of the majority of genes related to DNA repair argues for their importance in the maintenance of life on earth. In plants, our understanding of DNA repair pathways is still very poor, the first plant repair genes having only been cloned in 1997 and the mechanisms of their products have not yet been characterized. The objective of our data mining work was to identify genes related to the base excision repair (BER) pathway, which are present in the database of the Sugarcane Expressed Sequence Tag (SUCEST) Project. This search was performed by tblastn program. We identified sugarcane clusters homologous to the majority of BER proteins used in the analysis and a high degree of conservation was observed. The best results were obtained with BER proteins from Arabidopsis thaliana. For some sugarcane BER genes, the presence of more than one form of mRNA is possible, as shown by the occurrence of more than one homologous EST cluster.Danos no DNA podem ser induzidos por um grande número de agentes físicos e químicos presentes no ambiente, como também por compostos produzidos pelo próprio metabolismo celular. Estes danos podem interferir com processos celulares como replicação e transcrição, levando a morte celular e/ou mutações. Os baixos níveis de mutação nas células são devidos à presença de vias enzimáticas, que reparam os danos no DNA. Diversos genes de reparo de DNA têm sido clonados e seus produtos caracterizados, principalmente em bactérias, leveduras e mamíferos. O interesse no estudo de mecanismos de reparo de DNA advém de seu envolvimento com a proteção da integridade da informação genética. A alta conservação observada para a maioria dos genes relacionados ao reparo de DNA, especialmente em eucariotos, aponta para sua importância para a manutenção da vida na terra. Em plantas, o conhecimento sobre os mecanismos de reparo de DNA é ainda reduzido. Os primeiros genes de reparo foram recentemente clonados e o mecanismo de ação de seus produtos está por ser caracterizado. Nosso objetivo neste trabalho de data mining foi identificar, no banco de dados gerados pelo projeto Genoma da Cana de Açúcar (Sugarcane Expressed Tag Project-SUCEST), genes relacionados ao reparo por excisão de bases (BER). Esta busca foi feita através do programa tblastn. Em cana de açúcar, foram identificados clusters homólogos para a maioria das proteínas BER analisadas e um alto grau de conservação foi observado. Os melhores resultados foram obtidos com proteínas BER de Arabidopsis thaliana. Para alguns homólogos BER de cana de açúcar, a presença de mais de uma forma de mRNA é possível, como definido pela ocorrência de mais de um cluster homólogo.

Lucymara F. Agnez-Lima; Sílvia R. Batistuzzo de Medeiros; Bruno S. Maggi; Giovanna A.S. Quaresma

2001-01-01

304

Base excision repair in sugarcane  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese Danos no DNA podem ser induzidos por um grande número de agentes físicos e químicos presentes no ambiente, como também por compostos produzidos pelo próprio metabolismo celular. Estes danos podem interferir com processos celulares como replicação e transcrição, levando a morte celular e/ou mutações. Os baixos níveis de mutação nas células são devidos à presença de vias enzimáticas, que reparam os danos no DNA. Diversos genes de reparo de DNA têm sido c (more) lonados e seus produtos caracterizados, principalmente em bactérias, leveduras e mamíferos. O interesse no estudo de mecanismos de reparo de DNA advém de seu envolvimento com a proteção da integridade da informação genética. A alta conservação observada para a maioria dos genes relacionados ao reparo de DNA, especialmente em eucariotos, aponta para sua importância para a manutenção da vida na terra. Em plantas, o conhecimento sobre os mecanismos de reparo de DNA é ainda reduzido. Os primeiros genes de reparo foram recentemente clonados e o mecanismo de ação de seus produtos está por ser caracterizado. Nosso objetivo neste trabalho de data mining foi identificar, no banco de dados gerados pelo projeto Genoma da Cana de Açúcar (Sugarcane Expressed Tag Project-SUCEST), genes relacionados ao reparo por excisão de bases (BER). Esta busca foi feita através do programa tblastn. Em cana de açúcar, foram identificados clusters homólogos para a maioria das proteínas BER analisadas e um alto grau de conservação foi observado. Os melhores resultados foram obtidos com proteínas BER de Arabidopsis thaliana. Para alguns homólogos BER de cana de açúcar, a presença de mais de uma forma de mRNA é possível, como definido pela ocorrência de mais de um cluster homólogo. Abstract in english DNA damage can be induced by a large number of physical and chemical agents from the environment as well as compounds produced by cellular metabolism. This type of damage can interfere with cellular processes such as replication and transcription, resulting in cell death and/or mutations. The low frequency of mutagenesis in cells is due to the presence of enzymatic pathways which repair damaged DNA. Several DNA repair genes (mainly from bacteria, yeasts and mammals) have (more) been cloned and their products characterized. The high conservation, especially in eukaryotes, of the majority of genes related to DNA repair argues for their importance in the maintenance of life on earth. In plants, our understanding of DNA repair pathways is still very poor, the first plant repair genes having only been cloned in 1997 and the mechanisms of their products have not yet been characterized. The objective of our data mining work was to identify genes related to the base excision repair (BER) pathway, which are present in the database of the Sugarcane Expressed Sequence Tag (SUCEST) Project. This search was performed by tblastn program. We identified sugarcane clusters homologous to the majority of BER proteins used in the analysis and a high degree of conservation was observed. The best results were obtained with BER proteins from Arabidopsis thaliana. For some sugarcane BER genes, the presence of more than one form of mRNA is possible, as shown by the occurrence of more than one homologous EST cluster.

Agnez-Lima, Lucymara F.; Medeiros, Sílvia R. Batistuzzo de; Maggi, Bruno S.; Quaresma, Giovanna A.S.

2001-12-01

305

Oxidative stress response in sugarcane  

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Full Text Available Oxidative stress response in plants is still poorly understood in comparison with the correspondent phenomenon in bacteria, yeast and mammals. For instance, nitric oxide is assumed to play various roles in plants although no nitric oxide synthase gene has yet been isolated. This research reports the results of a search of the sugarcane expressed sequence tag (SUCEST) database for homologous sequences involved in the oxidative stress response. I have not found any gene similar to nitric oxide synthase in the SUCEST database although an alternative pathway for nitric oxide synthesis was proposed. I have also found several genes involved in antioxidant defense, e.g. metal chelators, low molecular weight compounds, antioxidant enzymes and repair systems. Ascorbate (vitamin C) is a key antioxidant in plants because it reaches high concentrations in cells and is a substrate for ascorbate peroxidase, an enzyme that I found in different isoforms in the SUCEST database. I also found many enzymes involved in the biosynthesis of low molecular weight antioxidants, which may be potential targets for genetic manipulation. The engineering of plants for increased vitamin C and E production may lead to improvements in the nutritional value and stress tolerance of sugarcane. The components of the antioxidant defense system interact and their synthesis is probably closely regulated. Transcription factors involved in regulation of the oxidative stress response in bacteria, yeast and mammals differ considerably among themselves and when I used them to search the SUCEST database only genes with weak similarities were found, suggesting that these transcription regulators are not very conserved. The involvement of reactive oxygen species and antioxidants in plant defense against pathogens is also discussed.

Soares Netto Luis Eduardo

2001-01-01

306

A quantitative genetics approach to nitrogen use efficiency in sugarcane  

UK PubMed Central (United Kingdom)

The economic and environmental consequences of inefficient use of nitrogen (N) fertiliser in agricultural crops is of concern worldwide, so new crop varieties with improved nitrogen use efficiency (NUE) are sought. Here, we report the first study of mapping quantitative trait loci (QTL) for nitrogen physiology traits in sugarcane. QTL analysis was undertaken for each parent of a segregating bi-parental sugarcane mapping population. We grew 168 progeny under limiting (0.2mM NH?NO?) and non-limiting (5.0mM NH?NO?) N supplies in two glasshouse experiments. Significant marker-trait associations (MTA) were detected in each treatment for shoot dry weight, root dry weight, total shoot N, shoot internal NUE (iNUE; measured as units shoot dry weight per unit N), leaf protein content and glutamine synthetase (GS) activity. MTA for GS activity did not co-locate with other traits except leaf protein content, indicating that variation in GS activity is not linked to plant size or iNUE during early growth. Under high N, there were no significant MTA for iNUE among markers from the male parent, Q165, an Australian commercial cultivar, but six MTA were found for markers inherited from the female parent, IJ76-514, a Saccharum officinarum ancestral variety. The results indicate that variation for iNUE under high N may be lower in commercial varieties than unimproved genotypes. Further, four MTA were consistent with previous field-based research on sugar and biomass production. Our study provides initial evidence that QTL may be incorporated in sugarcane breeding programs targeting improved NUE.

Whan Alex; Robinson Nicole; Lakshmanan Prakash; Schmidt Susanne; Aitken Karen

2010-01-01

307

Biosynthesis of secondary metabolites in sugarcane  

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Full Text Available A set of genes related to secondary metabolism was extracted from the sugarcane expressed sequence tag (SUCEST) database and was used to investigate both the gene expression pattern of key enzymes regulating the main biosynthetic secondary metabolism pathways and the major classes of metabolites involved in the response of sugarcane to environmental and developmental cues. The SUCEST database was constructed with tissues in different physiological conditions which had been collected under varied situation of environmental stress. This database allows researchers to identify and characterize the expressed genes of a wide range of putative enzymes able to catalyze steps in the phenylpropanoid, isoprenoid and other pathways of the special metabolic mechanisms involved in the response of sugarcane to environmental changes. Our results show that sugarcane cDNAs encoded putative ultra-violet induced sesquiterpene cyclases (SC); chalcone synthase (CHS), the first enzyme in the pathway branch for flavonoid biosynthesis; isoflavone synthase (IFS), involved in plant defense and root nodulation; isoflavone reductase (IFR), a key enzyme in phenylpropanoid phytoalexin biosynthesis; and caffeic acid-O-methyltransferase, a key enzyme in the biosynthesis of lignin cell wall precursors. High levels of CHS transcripts from plantlets infected with Herbaspirillum rubri or Gluconacetobacter diazotroficans suggests that agents of biotic stress can elicit flavonoid biosynthesis in sugarcane. From this data we have predicted the profile of isoprenoid and phenylpropanoid metabolism in sugarcane and pointed the branches of secondary metabolism activated during tissue-specific stages of development and the adaptive response of sugarcane to agents of biotic and abiotic stress, although our assignment of enzyme function should be confirmed by careful biochemical and genetic supporting evidence.

França S.C.; Roberto P.G.; Marins M.A.; Puga R.D.; Rodrigues A.; Pereira J.O.

2001-01-01

308

Solarização do solo e incorporação de fontes de matéria orgânica no controle de Pythium spp.  

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Full Text Available O objetivo deste trabalho foi avaliar o efeito da solarização do solo, associada à incorporação de lodo de esgoto, cama-de-frango e casca de Pinus, no controle de Pythium spp. Foram conduzidos dois ensaios, um em área cultivada comercialmente com crisântemo e outro em área artificialmente infestada com Pythium spp. em cultivo de pepino. A adição de cama-de-frango induziu a supressividade do solo ao patógeno, visto que resultou em maiores temperaturas no solo solarizado, aumento na condutividade elétrica e maior atividade microbiana do solo, avaliada pela hidrólise de diacetato de fluoresceína e desprendimento de CO2. Por outro lado, o lodo de esgoto e a casca de Pinus não induziram a supressividade ao patógeno. A solarização não teve efeito no crescimento da parte aérea e no peso de matéria fresca de raízes de plantas de crisântemo, mas teve efeito significativo no controle do patógeno no ensaio conduzido com pepino.

Ghini Raquel; Schoenmaker Ivone Alberta Swart; Bettiol Wagner

2002-01-01

309

Partial saturation under ebb and flow irrigation suppresses Pythium root rot of ornamentals  

UK PubMed Central (United Kingdom)

The timing of ebb and flow cycles for flooded floor irrigation systems was manipulated to alter the water content of the root medium. Ornamental species were grown under the different irrigation regimes to determine if the spread and severity of Pythium root rot was affected by altered sub-irrigation delivery practices. One floor delivered and drained water quickly to achieve a partial saturation of the root medium (approximately 25% less soil water) so that minimal leachates drained from the pot. The other floor operated more slowly as a standard commercial delivery system allowing the pots to imbibe more water. During 2007–2009, poinsettia, geranium or chrysanthemum crops were grown on each floor in five separate experiments. For each experiment, 15 plants were artificially inoculated with Pythium aphanidermatum or Pythium ultimum and set on the floor in a line immediately adjacent to a row of drainage ports. Disease was monitored by evaluating foliar symptoms and by rating the root systems for percent root rot. In three of the five experiments, disease was significantly reduced under partial saturation as compared to the standard saturation. In some instances, root infection as evidenced by re-isolation of the pathogen on agar, was less on plants receiving partial saturation than on standard saturation. Plants were smaller, more compact and of higher horticultural value under partial saturation than with standard saturation. These findings should encourage growers to adopt partial saturation management practices when using ebb and flow irrigation in order to reduce damage from disease after Pythium inoculum is present.

Elmer WH; Gent MPN; McAvoy RJ

2012-03-01

310

Dual infection with Pythium insidiosum and Blastomyces dermatitidis in a dog.  

Science.gov (United States)

A 4-year-old male neutered Labrador Retriever with severe gastrointestinal signs, but no respiratory signs, was diagnosed with multifocal pyogranulomatous gastritis, enteritis, and lymphadenitis with intralesional hyphae and multifocal pyogranulomatous pneumonia with intralesional yeast. Based on cytologic evaluation, histologic examination with special stains, and immunohistochemical analysis of tissues collected antemortem or at necropsy, dual infections with Pythium insidiosum and Blastomyces dermatitidis were detected and are reported for the first time. PMID:22747656

Connolly, Sara L; Frank, Chad; Thompson, Craig A; Van Alstine, William G; Gelb, Hylton; Heng, Hock Gan; Klosterman, Emily; Kiupel, Matti; Grooters, Amy M

2012-06-29

311

Dual infection with Pythium insidiosum and Blastomyces dermatitidis in a dog.  

UK PubMed Central (United Kingdom)

A 4-year-old male neutered Labrador Retriever with severe gastrointestinal signs, but no respiratory signs, was diagnosed with multifocal pyogranulomatous gastritis, enteritis, and lymphadenitis with intralesional hyphae and multifocal pyogranulomatous pneumonia with intralesional yeast. Based on cytologic evaluation, histologic examination with special stains, and immunohistochemical analysis of tissues collected antemortem or at necropsy, dual infections with Pythium insidiosum and Blastomyces dermatitidis were detected and are reported for the first time.

Connolly SL; Frank C; Thompson CA; Van Alstine WG; Gelb H; Heng HG; Klosterman E; Kiupel M; Grooters AM

2012-09-01

312

Development of new formulations of Bacillus subtilis for management of tomato damping-off caused by Pythium aphanidermatum  

Energy Technology Data Exchange (ETDEWEB)

Formulations of a strain of Bacillus subtilis AUBS-1 inhibitory to the growth of the damping-off pathogen, Pythium aphanidermatum, were developed for seed treatment. The formulations included a talc-based powder, lignite-based powder, lignite + fly ash-based powder, wettable powder, bentonite-paste, polyethylene glycol (PEG) paste and a water-dispersible tablet. Formulations were stored at room temperature for 2 years and frequently sampled to test their shelf life. Populations of bacteria in the formulations were stable for up to 2 years storage at room temperature (28{degree}C). Viability of propagules in lignite, lignite + fly ash, bentonite paste, wettable powder and water dispersible tablet formulations was 100% for up to 1 year. However, the viability of propagules was significantly reduced in talc, wettable powder, PEG paste and tablet formulations beyond 1 year of storage. Seed treatment of tomato with these formulations resulted in effective control of damping-off caused by P. aphanidermatum, and also enhanced plant biomass under glasshouse and field conditions. Active rhizosphere colonization by the bacterium was observed on tomato plants grown from seeds treated with the above formulations.

Jayaraj, J.; Radhakrishnan, N.V.; Kannan, R.; Sakthivel, K.; Suganya, D.; Venkatesan, S.; Velazhahan, R. [Simon Fraser University, Burnaby, B (Canada). Dept. of Biological Science

2005-02-15

313

The oomycete Pythium oligandrum expresses putative effectors during mycoparasitism of Phytophthora infestans and is amenable to transformation.  

UK PubMed Central (United Kingdom)

The oomycete Pythium oligandrum is a mycoparasitic biocontrol agent that is able to antagonise several plant pathogens, and can promote plant growth. In order to test the potential usefulness of P. oligandrum as a biocontrol agent against late blight disease caused by the oomycete Phytophthora infestans, we investigated the interaction between P. oligandrum and Ph. infestans using the green fluorescent protein (GFP) as a reporter gene. A CaCl(2) and polyethylene-glycol-based DNA transformation protocol was developed for P. oligandrum and transformants constitutively expressing GFP were produced. Up to 56 % of P. oligandrum transformants showed both antibiotic resistance and fluorescence. Mycoparasitic interactions, including coiling of P. oligandrum hyphae around Ph. infestans hyphae, were observed with fluorescent microscopy. To gain further insights into the nature of P. oligandrum mycoparasitism, we sequenced 2376 clones from cDNA libraries of P. oligandrum mycelium grown in vitro, or on heat-killed Ph. infestans mycelium as the sole nutrient source. 1219 consensus sequences were obtained including transcripts encoding glucanases, proteases, protease inhibitors, putative effectors and elicitors, which may play a role in mycoparasitism. This represents the first published expressed sequence tag (EST) resource for P. oligandrum and provides a platform for further molecular studies and comparative analysis in the Pythiales.

Horner NR; Grenville-Briggs LJ; van West P

2012-01-01

314

Biological Control of Pythium aphanidermatum, the Causal Agent of Damping off Disease of Greenhouse Cucurbits in Kerman Province of Iran  

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Full Text Available Actinomycetes enhance soil fertility and have antagonistic activity against wide range of plant root-pathogens. These micro organisms were isolated from agricultural soils of Kerman and Fars Provinces as pure cultures. Pythium aphanidermatum, causes damping off and root and stem rots of cucurbits worldwide. From 178 Actinomycetes isolates, 43 inhibited growth of the pathogen in culture plates and two of the most active isolates exhibited biological control of the pathogen under greenhouse conditions. When plants were grown in sterile soil mix and treated both with Actinomycetes and the pathogen, the number of healthy plants increased dramatically and the symptoms on diseased plants were less severe in comparison with seedlings treated with the pathogen alone. From the collected data it was well conclusive that in greenhouse tests, soil applications of Actinomycetes controlled causal agent of damping off in cucurbit seedlings. Antifungal activity was of fungicidal type on the pathogen mycelia. Regarding biotechnological implications, the results indicate that the active isolates can be investigated for use as biofertilizers, biofungicides and use in future development of recombinant DNA in cucurbits bearing elevated resistance to damping off. Field trials of the active isolates are under investigation.

F. Sharifi; P. Rashid Farrokhi; G.H. Shahidi Bonjar; S. Aghighi; F. Aram; E. Khalesi

2007-01-01

315

The oomycete Pythium oligandrum expresses putative effectors during mycoparasitism of Phytophthora infestans and is amenable to transformation.  

Science.gov (United States)

The oomycete Pythium oligandrum is a mycoparasitic biocontrol agent that is able to antagonise several plant pathogens, and can promote plant growth. In order to test the potential usefulness of P. oligandrum as a biocontrol agent against late blight disease caused by the oomycete Phytophthora infestans, we investigated the interaction between P. oligandrum and Ph. infestans using the green fluorescent protein (GFP) as a reporter gene. A CaCl(2) and polyethylene-glycol-based DNA transformation protocol was developed for P. oligandrum and transformants constitutively expressing GFP were produced. Up to 56 % of P. oligandrum transformants showed both antibiotic resistance and fluorescence. Mycoparasitic interactions, including coiling of P. oligandrum hyphae around Ph. infestans hyphae, were observed with fluorescent microscopy. To gain further insights into the nature of P. oligandrum mycoparasitism, we sequenced 2376 clones from cDNA libraries of P. oligandrum mycelium grown in vitro, or on heat-killed Ph. infestans mycelium as the sole nutrient source. 1219 consensus sequences were obtained including transcripts encoding glucanases, proteases, protease inhibitors, putative effectors and elicitors, which may play a role in mycoparasitism. This represents the first published expressed sequence tag (EST) resource for P. oligandrum and provides a platform for further molecular studies and comparative analysis in the Pythiales. PMID:22208599

Horner, Neil R; Grenville-Briggs, Laura J; van West, Pieter

2011-09-29

316

Inhibitory effects of furanone metabolites of a rhizobacterium, Pseudomonas jessenii, on phytopathogenic Aphanomyces cochlioides and Pythium aphanidermatum  

UK PubMed Central (United Kingdom)

An antagonistic rhizobacterium, Pseudomonas jessenii EC-S101, isolated from the rhizosphere of spinach, produces two related secondary metabolites, 3-[(1R)-hydroxyoctyl]-5-methylene-2(5H)-furanone (4,5-didehydroacaterin) (1) and 3-[(1R)-hydroxyhexyl]-5-methylene-2(5H)-furanone (2). This study demonstrated their in vitro inhibitory effects, in particular those of (1), against Aphanomyces cochlioides AC-5 and Pythium aphanidermatum PA-5. The compounds inhibited radial growth and induced morphological abnormalities characterized by hyperbranching and periodic swelling in AC-5 and PA-5 hyphae, respectively. Staining with rhodamine-phalloidin, which binds to plasma-membrane-associated filamentous-actin (F-actin), revealed that tip-specific actin filaments were remodelled into a plaque-like form at an early stage of encounter (up to 24 h) with (1) or (2), whereas at later stages of encounter (48 h), the plaques were eliminated, reflecting the disorganization of actin arrays in the morphologically abnormal AC-5 and PA-5 hyphae. A similar response of actin disorganization was observed in AC-5 and PA-5 hyphae upon treatment with latrunculin B (3), an actin-assembly inhibitor produced by a sea sponge. It is suggested that (1) and (2) caused actin disorganization and their inhibitory activities were comparable to that of (3). Further ultrastructural observations substantiated abnormal functioning and delocalization of F-actin-linked cell organelles.

Deora A; Hatano E; Tahara S; Hashidoko Y

2010-02-01

317

A Study of Sugarcane Leaf-Removal Machinery during Harvest  

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Full Text Available Problem statement: Sugarcane leaf-removing tools could help speed up sugarcane harvest and reduce contamination. Moreover, leaf-removal machinery can solve the problems of sugarcane burning and workers can increase sugarcane harvest production too. The purpose of this research was to study the use of leaf-removal machinery in the post-harvest production of sugarcane to reduce harvest production time and contaminant. Approach: This study focused on the LK92-11 variety of sugarcane having a harvesting period of 12 months, a density of 9,387 stems/rai and could produce 14.01 tons/rai including cane top and, leaves and leaf sheaths of 1675.2 and 180 kg/rai. Sugarcane leaf-removal machinery was applied to a small engine power from a grass-cutting machine. A rotate dish applied 4 different materials, tendon string, soft wire, medium wire and sling for sugarcane leaf-removing. The machine was operated at a constant speed. The efficiency of the sugarcane leaf-removal machinery indicated the capacity of sugarcane leaf-removing by area and operation time. Results: The quantity of leaves and leaf sheaths affect the speed of harvest production. Moreover, leaves and leaf sheaths increase the waste material in production and also contaminate the sugar and the sugar production system with clay, sand, and mud from the fields. Traditional methods for sugarcane harvest without removing leaf took 37 h/rai to complete, but sugarcane leaf-removing could reduce the sugarcane harvest process to 11.4 h/rai. Conclusion: The material of the blades in de-leafing machine is crucial to the efficiency of harvest production time. Blades made from poor materials can cause tangling and clogging in the rotator dish, which increases maintenance time. Further developments in sugarcane leaf removal systems will create dramatic improvement in sugarcane production.

Sopa Cansee

2010-01-01

318

Effects of plant densities and management of purple nutsedge on sugarcane yield and effect of growth stages and main way of herbicides contact and absorption on the control of tubers.  

UK PubMed Central (United Kingdom)

Field experiments carried out with Cyperus rotundus L. at low (58-246), medium (318-773), and high (675-1198 shoots/m2) densities showed sugarcane yield reductions of 13.5, 29.3, and 45.2%, respectively in relation to the control. In the second field experiment, the integration of a mechanic method with two sequences of plowing and disking operations in the dry season, and complementary applications of trifloxysulfuron-sodium + ametrine and sulfentrazone (rainy season) was studied. Average of the chain connected to original shoot showed 92, 95, and 65% of reduction with trifloxysulfuron-sodium + ametrine and surfactant, at the application stages "early," preflowering, and full flowering, respectively.

Durigan JC

2005-01-01

319

Effects of plant densities and management of purple nutsedge on sugarcane yield and effect of growth stages and main way of herbicides contact and absorption on the control of tubers.  

Science.gov (United States)

Field experiments carried out with Cyperus rotundus L. at low (58-246), medium (318-773), and high (675-1198 shoots/m2) densities showed sugarcane yield reductions of 13.5, 29.3, and 45.2%, respectively in relation to the control. In the second field experiment, the integration of a mechanic method with two sequences of plowing and disking operations in the dry season, and complementary applications of trifloxysulfuron-sodium + ametrine and sulfentrazone (rainy season) was studied. Average of the chain connected to original shoot showed 92, 95, and 65% of reduction with trifloxysulfuron-sodium + ametrine and surfactant, at the application stages "early," preflowering, and full flowering, respectively. PMID:15656168

Durigan, Julio Cezar

2005-01-01

320

Disinfection of Pythium-infested recirculation water by UV-oxidation technology.  

Science.gov (United States)

Selective disinfection against Pythium aphanidermatum in recirculation water was tested with UV-irradiation and with UV-oxidation technology with the objective to reduce the electrical energy consumption per cubic meter treated water. UV-oxidation technology is based on injection of hydrogen peroxide in recirculation water, just before passage along a UV-lamp, thus creating hydroxyl radicals. Pythium aphanidermatum was applied artificially to recirculation water from tomatoes, grown, in rockwool and coconut fibre. Other parameters in this study were pH and transmission value (T10) of the infested recirculation water. Results indicated that the recommended UV-C dose of 100 mJ/cm2 for elimination of fungal pathogens in general can be lowered in case recirculation water is infected with Pythium aphanidermatum only. When UV-oxidation technology was applied with 1 mmol hydrogen peroxide per litre recirculation water, the UV-C dose could be reduced even more in comparison with merely UV irradiation. PMID:12425022

Runia, W T; Boonstra, S

2001-01-01

 
 
 
 
321

Biochemical and physiological responses of sugarcane cultivars to soil water deficiencies  

Directory of Open Access Journals (Sweden)

Full Text Available For sugarcane (Saccharum spp.) crops, the effects of an environmental stress, especially water deficiency, may cause severe productivity reduction, inferring negatively in the sugarcane industry. The tolerance of two sugarcane cultivars to a lack of water was made by analyzing the levels of the osmoprotectors, trehalose and free proline, and the biometrical variables of their initial growth. Biochemical and physiological responses of the cultivars, when subjected to water stress, were assayed to determine how these plants tolerate drought. The study was conducted in an acclimatized greenhouse (29.7 ± 4.3ºC and 75.0 ± 10.1% relative humidity) during 100 days and was divided into random blocks using a factorial 2 × 3 × 2 design (sugarcane cultivars × water availability × time periods) with four replicates. Forty days after germination, sugarcane was planted in pots (12 dm³) containing topsoil material taken from a medium textured Rhodic Ferralsol, submitted to three levels of water availability (WAS): 55% (control), 40% (moderate stress) and 25% (severe stress), for 60 days. The effect of the WAS on the accumulation of trehalose and free proline was detected in both cultivars, although it was found to be more distinctive for the cv. IAC91-5155. Trehalose and free proline are biochemical and physiological indicators of water deficiency. The cv. IAC91-5155 had altered growth and allocation of biomass when subjected to severe water stress conditions. The univariate and the multivariate analysis of the biochemical and physiological responses, presented by the IAC91-5155 cultivar, indicate relative tolerance to drought conditions.

Rafaela Josemara Barbosa Queiroz; Durvalina Maria Mathias dos Santos; Antonio Sergio Ferraudo; Samira Domingues Carlin; Marcelo de Almeida Silva

2011-01-01

322

Biochemical and physiological responses of sugarcane cultivars to soil water deficiencies  

Scientific Electronic Library Online (English)

Full Text Available Abstract in english For sugarcane (Saccharum spp.) crops, the effects of an environmental stress, especially water deficiency, may cause severe productivity reduction, inferring negatively in the sugarcane industry. The tolerance of two sugarcane cultivars to a lack of water was made by analyzing the levels of the osmoprotectors, trehalose and free proline, and the biometrical variables of their initial growth. Biochemical and physiological responses of the cultivars, when subjected to water (more) stress, were assayed to determine how these plants tolerate drought. The study was conducted in an acclimatized greenhouse (29.7 ± 4.3ºC and 75.0 ± 10.1% relative humidity) during 100 days and was divided into random blocks using a factorial 2 × 3 × 2 design (sugarcane cultivars × water availability × time periods) with four replicates. Forty days after germination, sugarcane was planted in pots (12 dm³) containing topsoil material taken from a medium textured Rhodic Ferralsol, submitted to three levels of water availability (WAS): 55% (control), 40% (moderate stress) and 25% (severe stress), for 60 days. The effect of the WAS on the accumulation of trehalose and free proline was detected in both cultivars, although it was found to be more distinctive for the cv. IAC91-5155. Trehalose and free proline are biochemical and physiological indicators of water deficiency. The cv. IAC91-5155 had altered growth and allocation of biomass when subjected to severe water stress conditions. The univariate and the multivariate analysis of the biochemical and physiological responses, presented by the IAC91-5155 cultivar, indicate relative tolerance to drought conditions.

Queiroz, Rafaela Josemara Barbosa; Santos, Durvalina Maria Mathias dos; Ferraudo, Antonio Sergio; Carlin, Samira Domingues; Silva, Marcelo de Almeida

2011-08-01

323

Sugarcane and other crops as fuel feedstocks  

Energy Technology Data Exchange (ETDEWEB)

The use of sugarcane as a feedstock for fuel alcohol production in Brazil, and in Zimbabwe Rhodesia and Panama stimulated tremendous interest in the potential of agricultural crops for renewable energy sources. The cost of the feedstock is important. Corn, the current major agricultural feedstock in US fuel alcohol production, costs 60 to 80% of the selling price of the alcohol produced from it. Production costs for sugarcane and sugarbeets are higher than for corn. Sugarcane and sugarbeets, yield more fermentable carbohydrates per acre than any other crop. Sugarcane has the distinct advantage of containing a large amount of fiber in the harvested portion. The feedstock cost of sugarcane can be reduced by producing more cane per acre. Sweet sorghum has been discussed as a fuel crop. Cassana, the tapioca source, is thought to be a fuel crop of major potential. Feedstock cost can also be reduced through management decisions that reduce costly practices. Cultivation and fertilizer costs can be reduced. The operating cost of the processing plant is affected by the choice of crops grown for feedstock, both by their cost and by availability. (DP)

Irvine, J.E.

1980-07-01

324

Using frozen sugarcane for alcohol production  

Energy Technology Data Exchange (ETDEWEB)

The three areas that produce sugarcane in the mainland US are subject to crop-damaging freezes. Florida has fewer freezes. Texas and Louisiana are hurt frequently. Hard freezes end processing for sugar production when dextrans form and prevent crystallization. Dextran is formed from sugar by bacteria. Work at the Audubon Sugar Institute, LSU, has shown that crystallization of sucrose can be achieved with juice from frozen sugarcane when enzymes are used to reduce the size of the dextran molecule. Frozen cane may also be processed for alcohol production. How long the cane would be suitable as feedstock was questioned; its use would depend on sugar content. Sugarcane has been tested for post-freeze deterioration at the US Sugarcane Field Laboratory for over 50 years, and the emphasis has been on the response of varieties selected for sugar production in post-freeze deterioration. The data indicated that juice from frozen sugarcane in any of the tests would be adequate for alcohol production; fermentation based on mash with a sugar content of 9 to 11% for rum, and 15% for industrial alcohol. Total fermentable carbohydrates in frozen cane would be even higher since the data did not include invert sugars or starch. 1 table. (DP)

Irvine, J.E.

1980-01-01

325

Effect of intercropping pepper with sugarcane on populations of Liriomyza huidobrensis (Diptera: Agromyzidae) and its parasitoids  

UK PubMed Central (United Kingdom)

The effect of intercropping pepper with sugarcane on populations of the leafminer Liriomyza huidobrensis Becker was investigated over two seasons (2007, 2008) in Yunnan, China. Populations of adults, the female:male sex ratios and the densities of larval mines were significantly higher in pepper monoculture than in intercropping in a 2:2 pattern (2 rows of pepper to 2 rows of sugarcane), which in turn were significantly higher than intercropping in a 1:2 pattern (1 row of pepper to 2 rows of sugarcane). The densities of the parasitoids of the leafminer were significantly higher in intercropping than in the pepper monoculture. The total parasitism rates were 71.6%, 22.5% and 5.9% in 2007, and 69.5%, 20.6% and 5.9% in 2008, in the 1:2, 2:2 and pepper monoculture, respectively. The lower densities of leafminer adults, the lower female:male sex ratio, and smaller numbers of larval mines in the intercropping systems were attributed to the intercropping pattern and the growth of pepper. These results indicate that intercropping is suitable for the control of L. huidobrensis on pepper plants. These results demonstrate the utility of intercropping of pepper with sugarcane in the management of L. huidobrensis.

Chen B; Wang J; Zhang L; Li Z; Xiao G

2011-03-01

326

Pythium insidiosum: relato do primeiro caso de infecção humana no Brasil Pythium insidiosum: report of the first case of human infection in Brazil  

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Full Text Available A pitiose é causada por microorganismo aquático, fungo-símile, o Pythium insidiosum, patógeno de homens e animais. Observou-se um paciente com úlcera fagedênica no membro inferior, com exame anatomopatológico sugestivo de zigomicose, pouco sensível à terapêutica antifúngica, obtendo-se cura por meio de ampla exérese. A comprovação etiológica resultou de métodos moleculares, com amplificação e seqüenciamento de DNA de organismo isolado em ágar Sabouraud, observando-se 100% de analogia com seqüências de P. insidiosum depositadas no GenBank.Pythiosis is caused by an aquatic fungus-like organism, Pythium insidiosum, pathogenic to men and animals. A patient with a phagedenic ulcer on the leg is reported. Histopathological examination was suggestive of zygomycosis, response to antifungal drugs was poor and cure was obtained by means of wide surgical excision. Etiologic diagnosis was confirmed by molecular amplification and DNA sequencing of colonies isolated in Sabouraud agar. After BLAST analysis, the sequence showed 100% identity with those of P. insidiosum deposited on the GenBank.

Silvio Alencar Marques; Eduardo Bagagli; Sandra M. G. Bosco; Rosangela M. P. Camargo; Mariangela E. A. Marques

2006-01-01

327

Pythium insidiosum: relato do primeiro caso de infecção humana no Brasil/ Pythium insidiosum: report of the first case of human infection in Brazil  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese A pitiose é causada por microorganismo aquático, fungo-símile, o Pythium insidiosum, patógeno de homens e animais. Observou-se um paciente com úlcera fagedênica no membro inferior, com exame anatomopatológico sugestivo de zigomicose, pouco sensível à terapêutica antifúngica, obtendo-se cura por meio de ampla exérese. A comprovação etiológica resultou de métodos moleculares, com amplificação e seqüenciamento de DNA de organismo isolado em ágar Sabouraud, observando-se 100% de analogia com seqüências de P. insidiosum depositadas no GenBank. Abstract in english Pythiosis is caused by an aquatic fungus-like organism, Pythium insidiosum, pathogenic to men and animals. A patient with a phagedenic ulcer on the leg is reported. Histopathological examination was suggestive of zygomycosis, response to antifungal drugs was poor and cure was obtained by means of wide surgical excision. Etiologic diagnosis was confirmed by molecular amplification and DNA sequencing of colonies isolated in Sabouraud agar. After BLAST analysis, the sequence showed 100% identity with those of P. insidiosum deposited on the GenBank.

Marques, Silvio Alencar; Bagagli, Eduardo; Bosco, Sandra M. G.; Camargo, Rosangela M. P.; Marques, Mariangela E. A.

2006-10-01

328

Carbon balance of sugarcane bioenergy systems  

Energy Technology Data Exchange (ETDEWEB)

An important criterion for bioenergy systems evaluation is their greenhouse gas mitigation potential. Sugarcane bioenergy systems are able to produce grid-bound surplus electricity but also have net CO{sub 2} emissions associated with the upstream fossil-fuel consumption for plantation management, transportation and processing of the fibrous biomass. However, when compared to coal-based power generation systems, sugarcane bioenergy systems are able to avoid CO{sub 2} emissions at rates that range between 1.081 and 1.137kgCO{sub 2}/k Wh depending on the cane-residue utilisation strategy adopted. As a consequence, sugarcane bioenergy systems stand out as promising energy projects for funding under the Kyoto Protocol's proposed clean development mechanism and joint implementation. (Author)

Beeharry, Revin Panray [Mauritius Univ., Dept. of Chemical and Sugar Engineering, Reduit (Mauritius)

2001-07-01

329

Induction and isolation of mutants in sugarcane  

International Nuclear Information System (INIS)

[en] A review of the progress made on the induction of mutations in sugarcane at the Sugarcane Breeding Institute, Coimbatore, is presented. A description of some of the mutants is given. A few disease-resistant mutants have been obtained. Yield of C.C.S./ha of some of the mutants has surpassed the parent variety. Selection based on individual canes has increased the mutation rate and stability of mutants. Different techniques such as decapitation, closer planting and growing vM1 generation at different N levels have been observed to be promising methods to increase mutation rate. Raising of plants from mutated tissues by in vitro culture seems to be a potential tool in induced mutagenesis in sugarcane. (author)

1976-05-21

330

Interaction of brassicaceous seed meal and apple rootstock on recovery of Pythium spp. and Pratylenchus penetrans from roots grown in replant soils  

Science.gov (United States)

Pythium spp. and Pratylenchus penetrans are significant components of the diverse pathogen complex that incites apple replant disease in Washington state. The structure of the Pythium population differs among orchard soils but is composed of multiple pathogenic species. Studies were conducted to d...

331

Efficacy of seed treatments in reducing seed and root rot of peas in the presence of metalaxyl-resistant Pythium, 2007  

Science.gov (United States)

Five organic seed treatments and eighteen commercial seed treatments were evaluated in a commercial pea field (sandy loam soil) in Paterson, WA to manage seed and root rot of processed peas. The soil from the field site had a mean of 89 total Pythium colonies and 27 metalaxyl-resistant Pythium colo...

332

Compost-Induced Suppression of Pythium Damping-Off Is Mediated by Fatty-Acid-Metabolizing Seed-Colonizing Microbial Communities  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Leaf composts were studied for their suppressive effects on Pythium ultimum sporangium germination, cottonseed colonization, and the severity of Pythium damping-off of cotton. A focus of the work was to assess the role of fatty-acid-metabolizing microbial communities in disease suppression. Suppress...

McKellar, Mary E.; Nelson, Eric B.

333

Complete genome sequence of the sugarcane nitrogen-fixing endophyte Gluconacetobacter diazotrophicus Pal5  

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Full Text Available Abstract Background Gluconacetobacter diazotrophicus Pal5 is an endophytic diazotrophic bacterium that lives in association with sugarcane plants. It has important biotechnological features such as nitrogen fixation, plant growth promotion, sugar metabolism pathways, secretion of organic acids, synthesis of auxin and the occurrence of bacteriocins. Results Gluconacetobacter diazotrophicus Pal5 is the third diazotrophic endophytic bacterium to be completely sequenced. Its genome is composed of a 3.9 Mb chromosome and 2 plasmids of 16.6 and 38.8 kb, respectively. We annotated 3,938 coding sequences which reveal several characteristics related to the endophytic lifestyle such as nitrogen fixation, plant growth promotion, sugar metabolism, transport systems, synthesis of auxin and the occurrence of bacteriocins. Genomic analysis identified a core component of 894 genes shared with phylogenetically related bacteria. Gene clusters for gum-like polysaccharide biosynthesis, tad pilus, quorum sensing, for modulation of plant growth by indole acetic acid and mechanisms involved in tolerance to acidic conditions were identified and may be related to the sugarcane endophytic and plant-growth promoting traits of G. diazotrophicus. An accessory component of at least 851 genes distributed in genome islands was identified, and was most likely acquired by horizontal gene transfer. This portion of the genome has likely contributed to adaptation to the plant habitat. Conclusion The genome data offer an important resource of information that can be used to manipulate plant/bacterium interactions with the aim of improving sugarcane crop production and other biotechnological applications.

Bertalan Marcelo; Albano Rodolpho; de Pádua Vânia; Rouws Luc; Rojas Cristian; Hemerly Adriana; Teixeira Kátia; Schwab Stefan; Araujo Jean; Oliveira André; França Leonardo; Magalhães Viviane; Alquéres Sylvia; Cardoso Alexander; Almeida Wellington; Loureiro Marcio; Nogueira Eduardo; Cidade Daniela; Oliveira Denise; Simão Tatiana; Macedo Jacyara; Valadão Ana; Dreschsel Marcela; Freitas Flávia; Vidal Marcia; Guedes Helma; Rodrigues Elisete; Meneses Carlos; Brioso Paulo; Pozzer Luciana; Figueiredo Daniel; Montano Helena; Junior Jadier; de Souza Filho Gonçalo; Martin Quintana Flores Victor; Ferreira Beatriz; Branco Alan; Gonzalez Paula; Guillobel Heloisa; Lemos Melissa; Seibel Luiz; Macedo José; Alves-Ferreira Marcio; Sachetto-Martins Gilberto; Coelho Ana; Santos Eidy; Amaral Gilda; Neves Anna; Pacheco Ana; Carvalho Daniela; Lery Letícia; Bisch Paulo; Rössle Shaila C; Ürményi Turán; Rael Pereira Alessandra; Silva Rosane; Rondinelli Edson; von Krüger Wanda; Martins Orlando; Baldani José; Ferreira Paulo CG

2009-01-01

334

Genome sequence of Enterobacter sp. strain SP1, an endophytic nitrogen-fixing bacterium isolated from sugarcane.  

UK PubMed Central (United Kingdom)

Enterobacter sp. strain SP1 is an endophytic nitrogen-fixing bacterium isolated from a sugarcane stem and can promote plant growth. The draft genome sequence of strain SP1 presented here will promote comparative genomic studies to determine the genetic background of interactions between endophytic enterobacteria and plants.

Zhu B; Chen M; Lin L; Yang L; Li Y; An Q

2012-12-01

335

Genome Sequence of Enterobacter sp. Strain SP1, an Endophytic Nitrogen-Fixing Bacterium Isolated from Sugarcane  

Science.gov (United States)

Enterobacter sp. strain SP1 is an endophytic nitrogen-fixing bacterium isolated from a sugarcane stem and can promote plant growth. The draft genome sequence of strain SP1 presented here will promote comparative genomic studies to determine the genetic background of interactions between endophytic enterobacteria and plants.

Zhu, Bo; Chen, Mingyue; Lin, Li; Yang, Litao; Li, Yangrui

2012-01-01

336

Variability induced through vegetative mutagenesis in sugarcane  

International Nuclear Information System (INIS)

Both physical and chemical mutagens were found to be effective in inducing genetic variations in sugarcane. Among the mutagens employed EMS(ethyl methane sulphonate) and gamma rays significantly reduced the germination of buds at all levels tested with LD 50 at 0.8% and 6 Kr., respectively. By repeated clonal selection, mutants for various morphological characters were isolated in pure form. An induced mutant combining red rot disease resistance alongwith improved leaf characters has shown commercial potential. The significance of induced mutations in basic genetic studies and improvement of sugarcane are discussed. (author). 11 refs., 4 tabs., 1 fig.

1989-01-01

337

Generation of crystalline silica from sugarcane burning.  

UK PubMed Central (United Kingdom)

Sugarcane leaves contain amorphous silica, which may crystallise to form crystalline silica polymorphs (cristobalite or quartz), during commercial sugarcane harvesting where sugarcane plants are burned. Respirable airborne particulate containing these phases may present an occupational health hazard. Following from an earlier pilot study (J. S. Le Blond, B. J. Williamson, C. J. Horwell, A. K. Monro, C. A. Kirk and C. Oppenheimer, Atmos. Environ., 2008, 42, 5558-5565) in which experimental burning of sugarcane leaves yielded crystalline silica, here we report on actual conditions during sugarcane burning on commercial estates, investigate the physico-chemical properties of the cultivated leaves and ash products, and quantify the presence of crystalline silica. Commercially grown raw sugarcane leaf was found to contain up to 1.8 wt% silica, mostly in the form of amorphous silica bodies (with trace impurities e.g., Al, Na, Mg), with only a small amount of quartz. Thermal images taken during several pre-harvest burns recorded temperatures up to 1056 degrees C, which is sufficient for metastable cristobalite formation. No crystalline silica was detected in airborne particulate from pre-harvest burning, collected using a cascade impactor. The sugarcane trash ash formed after pre-harvest burning contained between 10 and 25 wt% SiO(2), mostly in an amorphous form, but with up to 3.5 wt% quartz. Both quartz and cristobalite were identified in the sugarcane bagasse ash (5-15 wt% and 1-3 wt%, respectively) formed in the processing factory. Electron microprobe analysis showed trace impurities of Mg, Al and Fe in the silica particles in the ash. The absence of crystalline silica in the airborne emissions and lack of cristobalite in trash ash suggest that high temperatures during pre-harvest burning were not sustained long enough for cristobalite to form, which is supported by the presence of low temperature sylvite and calcite in the residual ash. The occurrence of quartz and cristobalite in bagasse ash is significant as the ash is recycled onto the fields where erosion and/or mechanical disturbance could break down the deposits and re-suspend respirable-sized particulate. Appropriate methods for treatment and disposal of bagasse ash must, therefore, be employed and adequate protection given to workers exposed to these dusts.

Le Blond JS; Horwell CJ; Williamson BJ; Oppenheimer C

2010-07-01

338

Starch-based plastic polymer degradation by the white rot fungus Phanerochaete chrysosporium grown on sugarcane bagasse pith: enzyme production.  

UK PubMed Central (United Kingdom)

In this study, starch metabolites and enzymes were determined during starch-based plastic polymer biodegradation by the white rot fungus Phanerochaete chrysosporium, grown in sugarcane bagasse pith in tubular reactors. Various metabolites, amylase, ligninase and cellulase production were measured during P. chrysosporium growth on sugarcane bagasse pith with added glucose and starch polymer. On-line respirometric analyses followed during 32 days confirmed the P. chrysosporium capability of growing on sugarcane bagasse pith with starch polymer degradation. Enzyme activity during secondary metabolism increased, and a 70% and 74% starch degradation was reached with and without glucose addition, generating low molecular weight metabolites (e.g.) dextrin, maltotriose, maltose and glucose that were detected by high performance liquid chromatography.

Roldán-Carrillo T; Rodríguez-Vázquez R; Díaz-Cervantes D; Vázquez-Torres H; Manzur-Guzmán A; Torres-Domínguez A

2003-01-01

339

Forecasting Regional Sugarcane Yield Based on Time Integral and Spatial Aggregation of MODIS NDVI  

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Full Text Available This study explored the suitability of the Normalized Difference Vegetation Index (NDVI) from the Moderate Resolution Imaging Spectrometer (MODIS) obtained for six sugar management zones, over nine years (2002–2010), to forecast sugarcane yield on an annual and zonal base. To take into account the characteristics of the sugarcane crop management (15-month cycle for a ratoon, accompanied with continuous harvest in Western Kenya), the temporal series of NDVI was normalized through an original weighting method that considered the growth period of the sugarcane crop (wNDVI), and correlated it with historical yield datasets. Results when using wNDVI were consistent with historical yield and significant at P-value = 0.001, while results when using traditional annual NDVI integrated over the calendar year were not significant. This correlation between yield and wNDVI is mainly drawn by the spatial dimension of the data set (R2 = 0.53, when all years are aggregated together), rather than by the temporal dimension of the data set (R2 = 0.1, when all zones are aggregated). A test on 2012 yield estimation with this model realized a RMSE less than 5 t·ha?1. Despite progress in the methodology through the weighted NDVI, and an extensive spatio-temporal analysis, this paper shows the difficulty in forecasting sugarcane yield on an annual base using current satellite low-resolution data. This is particularly true in the context of small scale farmers with fields measuring less than the size of MODIS 250 m pixel, and in the context of a 15-month crop cycle with no seasonal cropping calendar. Future satellite missions should permit monitoring of sugarcane yields using image resolutions that facilitate extraction of crop phenology from a group of individual plots.

Betty Mulianga; Agnès Bégué; Margareth Simoes; Pierre Todoroff

2013-01-01

340

Sugarcane starch: quantitative determination and characterization/ Amido de cana-de-açúcar: determinação quantitativa e caracterização  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese O amido é encontrado na cana-de-açúcar como um polissacarídeo de reserva. A quantidade depende de diversos fatores. Este trabalho visou a determinação do conteúdo de amido em diferentes variedades de cana-de-açúcar durante o período de Maio a Novembro de 2007; e determinação de algumas características do amido de cana-de-açúcar como: estrutura e tamanho dos grânulos de amido; determinação da temperatura de gelificação; determinação da filtrabilidade (more) da solução de amido de cana-de-açúcar; susceptibilidade do amido de cana-de-açúcar às enzimas glicoamilase, pululanase, -amilases bacterianas e fúngica comerciais. Foi testado também a susceptibilidade do amido de cana-de-açúcar à enzima amilolítica desramificante isoamilase de Flavobacterium sp. O amido de cana-de-açúcar apresentou forma esférica e diâmetro entre 1-3 µm. O amido de cana-de-açúcar complexado com iodo apresentou maior absorção na faixa de 540 a 620 nm. O amido de cana-de-açúcar in natura mostrou maior susceptibilidade à enzima glicoamilase em relação aos outros amidos testados. O amido de cana-de-açúcar mostrou susceptibilidade à enzima amilolítica desramificante pululanase de modo similar ao amido de arroz ceroso. O amido de cana-de-açúcar mostrou susceptibilidade às ?-amilases de Bacillus subtilis, Bacillus licheniformis e Aspergillus oryzae de modo similar aos outros amidos testados produzindo glicose; maltose; maltotriose; maltotetraose e ?- dextrinas limite. Abstract in english Starch is found in sugarcane as a storage polysaccharide. Starch concentrations vary widely depending on the country, variety, developmental stage, and growth conditions. The purpose of this study was to determine the starch content in different varieties of sugarcane, between May and November 2007, and some characteristics of sugarcane starch such as structure and granules size; gelatinization temperature; starch solution filterability; and susceptibility to glucoamylase (more) , pullulanase, and commercial bacterial and fungal ?-amylase enzymes. Susceptibility to debranching amylolytic isoamylase enzyme from Flavobacterium sp. was also tested. Sugarcane starch had spherical shape with a diameter of 1-3 µm. Sugarcane starch formed complexes with iodine, which showed greater absorption in the range of 540 to 620 nm. Sugarcane starch showed higher susceptibility to glucoamylase compared to that of waxy maize, cassava, and potato starch. Sugarcane starch also showed susceptibility to debranching amylolytic pullulanases similar to that of waxy rice starch. It also showed susceptibility to ?-amylase from Bacillus subtilis, Bacillus licheniformis, and Aspergillus oryzae similar to that of the other tested starches producing glucose, maltose, maltotriose, maltotetraose, maltopentose and limit ?- dextrin.

Figueira, Joelise de Alencar; Carvalho, Priscila Hoffmann; Sato, Hélia Harumi

2011-09-01

 
 
 
 
341

Sugarcane starch: quantitative determination and characterization Amido de cana-de-açúcar: determinação quantitativa e caracterização  

Directory of Open Access Journals (Sweden)

Full Text Available Starch is found in sugarcane as a storage polysaccharide. Starch concentrations vary widely depending on the country, variety, developmental stage, and growth conditions. The purpose of this study was to determine the starch content in different varieties of sugarcane, between May and November 2007, and some characteristics of sugarcane starch such as structure and granules size; gelatinization temperature; starch solution filterability; and susceptibility to glucoamylase, pullulanase, and commercial bacterial and fungal ?-amylase enzymes. Susceptibility to debranching amylolytic isoamylase enzyme from Flavobacterium sp. was also tested. Sugarcane starch had spherical shape with a diameter of 1-3 µm. Sugarcane starch formed complexes with iodine, which showed greater absorption in the range of 540 to 620 nm. Sugarcane starch showed higher susceptibility to glucoamylase compared to that of waxy maize, cassava, and potato starch. Sugarcane starch also showed susceptibility to debranching amylolytic pullulanases similar to that of waxy rice starch. It also showed susceptibility to ?-amylase from Bacillus subtilis, Bacillus licheniformis, and Aspergillus oryzae similar to that of the other tested starches producing glucose, maltose, maltotriose, maltotetraose, maltopentose and limit ?- dextrin.O amido é encontrado na cana-de-açúcar como um polissacarídeo de reserva. A quantidade depende de diversos fatores. Este trabalho visou a determinação do conteúdo de amido em diferentes variedades de cana-de-açúcar durante o período de Maio a Novembro de 2007; e determinação de algumas características do amido de cana-de-açúcar como: estrutura e tamanho dos grânulos de amido; determinação da temperatura de gelificação; determinação da filtrabilidade da solução de amido de cana-de-açúcar; susceptibilidade do amido de cana-de-açúcar às enzimas glicoamilase, pululanase, -amilases bacterianas e fúngica comerciais. Foi testado também a susceptibilidade do amido de cana-de-açúcar à enzima amilolítica desramificante isoamilase de Flavobacterium sp. O amido de cana-de-açúcar apresentou forma esférica e diâmetro entre 1-3 µm. O amido de cana-de-açúcar complexado com iodo apresentou maior absorção na faixa de 540 a 620 nm. O amido de cana-de-açúcar in natura mostrou maior susceptibilidade à enzima glicoamilase em relação aos outros amidos testados. O amido de cana-de-açúcar mostrou susceptibilidade à enzima amilolítica desramificante pululanase de modo similar ao amido de arroz ceroso. O amido de cana-de-açúcar mostrou susceptibilidade às ?-amilases de Bacillus subtilis, Bacillus licheniformis e Aspergillus oryzae de modo similar aos outros amidos testados produzindo glicose; maltose; maltotriose; maltotetraose e ?- dextrinas limite.

Joelise de Alencar Figueira; Priscila Hoffmann Carvalho; Hélia Harumi Sato

2011-01-01

342

Physicochemical Properties of Pyrolysis Bio-Oil from Sugarcane Straw and Sugarcane in Natura  

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Full Text Available Under the renewable energy context, sugarcane biomass pyrolysis has been growing as a convenient route to produce bio-oil, which can be set into the chemical industry and refineries as building blocks or combustion fuel. In this work sugarcane straw was submitted to direct pyrolysis in a fluidized bed pilot plant at 500°C, in presence of air. Sugarcane in natura was also pyrolysed as a model for comparison, in order to determine the viability of processing different sources of raw biomass. The physicochemical characterization of the biomass precursors as well as of the bio-oils was also carried out, which points both biomass feedstocks as suitable for bio-oil production in terms of viscosity, surface tension, density and acidity. The bio-oil obtained from sugarcane in natura presented higher carbon and hydrogen content as well as lower oxygen content. On the other hand, the metal content is higher in the bio-oil obtained from sugarcane straw, in special the iron and potassium contents were 807 ppm and 123 ppm against 27 ppm and 1 ppm in the bio-oil from sugarcane in natura. Aliphatic and aromatic compounds as well as carbohydrates scaffolds were identified as the main components of the bio-oil. GC-MS analyses showed aromatic products from lignine fragmentation and free sugars and sugar derivatives.

Josilaine A. C. Durange; Margareth R. L. Santos; Marcelo M. Pereira; Luiz A. P. Fernandes Jr.; Marcio N. Souza; Anderson N. Mendes; Liena M. Mesa; Caio G. Sánchez; Elisabete M. S. Sanchez; Juan M. M. Pérez; Nakédia M. F. Carvalho

2013-01-01

343

Study of sugarcane pieces as yeast supports for ethanol production from sugarcane juice and molasses.  

UK PubMed Central (United Kingdom)

Due to the environmental concerns and the increasing price of oil, bioethanol was already produced in large amount in Brazil and China from sugarcane juice and molasses. In order to make this process competitive, we have investigated the suitability of immobilized Saccharomyces cerevisiae strain AS2.1190 on sugarcane pieces for production of ethanol. Electron microscopy clearly showed that cell immobilization resulted in firm adsorption of the yeast cells within subsurface cavities, capillary flow through the vessels of the vascular bundle structure, and attachment of the yeast to the surface of the sugarcane pieces. Repeated batch fermentations using sugarcane supported-biocatalyst were successfully carried out for at least ten times without any significant loss in ethanol production from sugarcane juice and molasses. The number of cells attached to the support increased during the fermentation process, and fewer yeast cells leaked into fermentation broth. Ethanol concentrations (about 89.73-77.13 g/l in average value), and ethanol productivities (about 59.53-62.79 g/l d in average value) were high and stable, and residual sugar concentrations were low in all fermentations (0.34-3.60 g/l) with conversions ranging from 97.67-99.80%, showing efficiency (90.11-94.28%) and operational stability of the biocatalyst for ethanol fermentation. The results of this study concerning the use of sugarcane as yeast supports could be promising for industrial fermentations.

Liang L; Zhang YP; Zhang L; Zhu MJ; Liang SZ; Huang YN

2008-12-01

344

An improved technique of inoculation for the artificial production of sugarcane smut and development of uniform diseased cane material  

Directory of Open Access Journals (Sweden)

Full Text Available Ustilago scitaminea, the causal organism of whip smut of sugarcane is basically a disease of meristematic tissue and it proliferates in young and actively growing tissues. It enters the healthy sugarcane plant through lateral buds, overcoming the barriers of bud scales. With the germination of an infected bud the fungus also gets activated and grows along with the apical meristem and later on manifests itself by converting the apical meristem in a very characteristic manner i.e., by producing a typical whip like smutty structure. Screening of sugarcane genotypes against smut is mainly done either by inoculating the setts (planting material) by dipping in the spore suspension of smut or by painting the buds with the spore suspension at the time ofplanting. Inoculated setts are planted in the field for germination and symptom expression. Every sugarcane pathologist faces problems of getting enough uniform smut infected sugarcane planting material (setts) for carrying out other experiments. Taking the analogy from the grassy shoot disease (GSD), where the mother shoot feeds the grassy lanky albinoid tillers, this technique was developed by inoculating the underground buds of the cane at the time of tillering, taking advantage of the canes own physiology of tillering and grand growth. In a highly susceptible variety like CoLk 7901 the success rate of infection was 83% with the new method compared with the common sett inoculation method that produced an infection level of only 36%. Moreover, the systematically infected tillers produced at the grand growth stage of sugarcane were excellent experimental material and thus could circumvent the lack of uniform infecting material for conducting other studies.

S.K. DUTTAMAJUMDER

2012-01-01

345

Microcollinearity between autopolyploid sugarcane and diploid sorghum genomes  

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Full Text Available Abstract Background Sugarcane (Saccharum spp.) has become an increasingly important crop for its leading role in biofuel production. The high sugar content species S. officinarum is an octoploid without known diploid or tetraploid progenitors. Commercial sugarcane cultivars are hybrids between S. officinarum and wild species S. spontaneum with ploidy at ~12×. The complex autopolyploid sugarcane genome has not been characterized at the DNA sequence level. Results The microsynteny between sugarcane and sorghum was assessed by comparing 454 pyrosequences of 20 sugarcane bacterial artificial chromosomes (BACs) with sorghum sequences. These 20 BACs were selected by hybridization of 1961 single copy sorghum overgo probes to the sugarcane BAC library with one sugarcane BAC corresponding to each of the 20 sorghum chromosome arms. The genic regions of the sugarcane BACs shared an average of 95.2% sequence identity with sorghum, and the sorghum genome was used as a template to order sequence contigs covering 78.2% of the 20 BAC sequences. About 53.1% of the sugarcane BAC sequences are aligned with sorghum sequence. The unaligned regions contain non-coding and repetitive sequences. Within the aligned sequences, 209 genes were annotated in sugarcane and 202 in sorghum. Seventeen genes appeared to be sugarcane-specific and all validated by sugarcane ESTs, while 12 appeared sorghum-specific but only one validated by sorghum ESTs. Twelve of the 17 sugarcane-specific genes have no match in the non-redundant protein database in GenBank, perhaps encoding proteins for sugarcane-specific processes. The sorghum orthologous regions appeared to have expanded relative to sugarcane, mostly by the increase of retrotransposons. Conclusions The sugarcane and sorghum genomes are mostly collinear in the genic regions, and the sorghum genome can be used as a template for assembling much of the genic DNA of the autopolyploid sugarcane genome. The comparable gene density between sugarcane BACs and corresponding sorghum sequences defied the notion that polyploidy species might have faster pace of gene loss due to the redundancy of multiple alleles at each locus.

Wang Jianping; Roe Bruce; Macmil Simone; Yu Qingyi; Murray Jan E; Tang Haibao; Chen Cuixia; Najar Fares; Wiley Graham; Bowers John; Van Sluys Marie-Anne; Rokhsar Daniel S; Hudson Matthew E; Moose Stephen P; Paterson Andrew H; Ming Ray

2010-01-01

346

EFECTO DE LA BIOFERTILIZACIÓN SOBRE EL CRECIMIENTO EN MACETA DE PLANTAS DE CAÑA DE AZÚCAR (Saccharum officinarum) EFEITO DA BIOFERTILIZAÇÃO NO CRESCIMENTO DE PLANTAS EM VASOS açúcar de cana (Saccharum officinarum) EFFECT OF BIOFERTILIZATION ON THE GROWTH OF POTTED SUGARCANE PLANTS (Saccharum officinarum)  

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Full Text Available El uso de microorganismos como fertilizante, ha demostrado tener efectos benéficos sobre el crecimiento de plantas y son una alternativa al uso de fertilizantes guímicos, sin embargo, cada microorganismo difiere en sus efectos benéficos. En este trabajo se evaluó el efecto de la aplicación de microorganismos fertilizantes, Azospirillum brasilense, Azotobacter chroccocum y Trichoderma lignorum sobre el crecimiento en maceta de plantas de caña de azúcar variedad CC 934418. El crecimiento de las plantas se midió en términos de diámetro del tallo, longitud de tallo y raíces, y número de hojas y raíces a los 15, 30 y 45 días de la siembra. El crecimiento de las plantas mostró diferencias estadísticamente significativas entre los tratamientos. Los microorganismos fertilizantes mostraron efecto positivo sobre el crecimiento de plantas de caña de azúcar, siendo Azospirillum brasilense y Trichoderma lignorum los microorganismos gue ejercieron mayor efecto sobre el diámetro del tallo y los sistemas radical y foliar de la planta. Se observaron los efectos beneficiosos de Trichoderma lignorum sobre el crecimiento de la hoja. Este es un nuevo aporte científico, ya que esta especie no ha sido reportada como promotora de crecimiento vegetal.0 uso de microrganismos como fertilizante, tem sido demonstrado gue têm efeitos benéficos no crescimento das plantas e são considerados uma alternativa ao uso de fertilizantes guímicos, no entanto, cada microrganismo possui diferentes efeitos benéficos. Neste estudo foi avaliado o efeito da aplicação de microorganismos fertilizantes, Azospirillum brasilense, Azotobacter chroccocum e Trichoderma lignorum no crescimento de cana-de-açucar da variedade CC 934418 plantadas em vasos. 0 crescimento das plantas foi medido em termos do diâmetro do caule, comprimento de caule e da raiz e número de folhas e raízes nos dias 15, 30 e 45 após a semeadura. 0 crescimento da planta mostrou diferenças significativas entre os tratamentos. Os microrganismos fertilizantes mostraram efeito positivo sobre o crescimento das plantas de cana, os microrganismos Azospirillum brasilense e Trichoderma lignorum exerceram um efeito maior em diâmetro do caule, sistema radicular e folhas da planta. Os efeitos benéficos do Trichoderma em lignorum crescimento da folha foram observadas. Esta é uma nova contribuição científica vez que esta espécie não foi relatada como a promoção de crescimento vegetal.The use of microorganisms as fertilizer has demonstrated beneficial effects on plant growth and is an alternative to chemical fertilizers. However, each microorganism has different beneficial effects. This study evaluated the effect of applying microorganism fertilizers, Azospirillum brasilense, Azotobacter chroccocum, and Trichoderma lignorum on the growth of potted sugarcane plants var. CC 934418. Plant growth was measured in terms of stem diameter, stem and root length, and the number of leaves and roots 15, 30, and 45 days after planting. Plant growth evidenced statistically significant differences among treatments. Microorganism fertilizers showed a positive effect on the growth of sugarcane plants, with Azospirillum brasilense and Trichoderma lignorum as the microorganisms that exercised the greatest effect on stem diameter, root systems, and plant foliation. Beneficial effects of Trichoderma lignorum on leaf growth were observed. This is a new scientific contribution since this species has not been reported as promoting plant growth.

LILIANA SERNA-COCK; CAMILO ARIAS-GARCÍA; LEIDY JOHANA VALENCIA HERNANDEZ

2011-01-01

347

Oxidative stress response in sugarcane  

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Full Text Available Oxidative stress response in plants is still poorly understood in comparison with the correspondent phenomenon in bacteria, yeast and mammals. For instance, nitric oxide is assumed to play various roles in plants although no nitric oxide synthase gene has yet been isolated. This research reports the results of a search of the sugarcane expressed sequence tag (SUCEST) database for homologous sequences involved in the oxidative stress response. I have not found any gene similar to nitric oxide synthase in the SUCEST database although an alternative pathway for nitric oxide synthesis was proposed. I have also found several genes involved in antioxidant defense, e.g. metal chelators, low molecular weight compounds, antioxidant enzymes and repair systems. Ascorbate (vitamin C) is a key antioxidant in plants because it reaches high concentrations in cells and is a substrate for ascorbate peroxidase, an enzyme that I found in different isoforms in the SUCEST database. I also found many enzymes involved in the biosynthesis of low molecular weight antioxidants, which may be potential targets for genetic manipulation. The engineering of plants for increased vitamin C and E production may lead to improvements in the nutritional value and stress tolerance of sugarcane. The components of the antioxidant defense system interact and their synthesis is probably closely regulated. Transcription factors involved in regulation of the oxidative stress response in bacteria, yeast and mammals differ considerably among themselves and when I used them to search the SUCEST database only genes with weak similarities were found, suggesting that these transcription regulators are not very conserved. The involvement of reactive oxygen species and antioxidants in plant defense against pathogens is also discussed.A resposta ao estresse oxidativo não é bem conhecida em plantas como em bactérias, leveduras e humanos. Por exemplo, assume-se que óxido nítrico tem várias funções em plantas apesar do gene que codificaria para óxido nítrico sintetase nunca ter sido isolado. Este trabalho descreve os resultados de uma busca no banco de dados de seqüências expressas de cana de açúcar (SUCEST) de genes envolvidos na resposta ao estresse oxidativo. Eu não encontrei genes similares a óxido nítrico no banco de dados do SUCEST, mas uma via alternativa para a produção deste radical livre pode ser proposta. Eu também encontrei vários genes envolvidos na defesa antioxidante, como quelantes de metais, antioxidantes de baixo peso molecular, enzimas antioxidantes e sistemas de reparo. Ascorbato (vitamina C) é um importante antioxidante em plantas porque é encontrado em altas concentrações em células vegetais e porque é substrato de ascorbato peroxidase, uma enzima que eu encontrei em diferentes isoformas no banco de dados do SUCEST. Eu também encontrei várias enzimas envolvidas na biossíntese de antioxidantes de baixo peso molecular que podem ser alvos para manipulação genética. A obtenção de plantas modificadas geneticamente que sintetizariam vitaminas C e E em altos níveis poderiam melhorar o valor nutricional e a tolerância a estresses de cana de açúcar. Os diversos componentes do sistema de defesa antioxidante interagem entre si e as suas sínteses devem ser muito bem reguladas. Fatores de transcrição envolvidos na regulação da resposta ao estresse oxidativo de bactérias, leveduras e de humanos diferem consideravelmente entre si e quando foram utilizados para buscas no banco de dados do SUCEST, somente genes com similaridades fracas foram encontrados, sugerindo que estas proteínas não são muito conservadas. O envolvimento de espécies reativas de oxigênio e nitrogênio na defesa de plantas contra patógenos também é discutido neste trabalho.

Luis Eduardo Soares Netto

2001-01-01

348

Oxidative stress response in sugarcane  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese A resposta ao estresse oxidativo não é bem conhecida em plantas como em bactérias, leveduras e humanos. Por exemplo, assume-se que óxido nítrico tem várias funções em plantas apesar do gene que codificaria para óxido nítrico sintetase nunca ter sido isolado. Este trabalho descreve os resultados de uma busca no banco de dados de seqüências expressas de cana de açúcar (SUCEST) de genes envolvidos na resposta ao estresse oxidativo. Eu não encontrei genes simil (more) ares a óxido nítrico no banco de dados do SUCEST, mas uma via alternativa para a produção deste radical livre pode ser proposta. Eu também encontrei vários genes envolvidos na defesa antioxidante, como quelantes de metais, antioxidantes de baixo peso molecular, enzimas antioxidantes e sistemas de reparo. Ascorbato (vitamina C) é um importante antioxidante em plantas porque é encontrado em altas concentrações em células vegetais e porque é substrato de ascorbato peroxidase, uma enzima que eu encontrei em diferentes isoformas no banco de dados do SUCEST. Eu também encontrei várias enzimas envolvidas na biossíntese de antioxidantes de baixo peso molecular que podem ser alvos para manipulação genética. A obtenção de plantas modificadas geneticamente que sintetizariam vitaminas C e E em altos níveis poderiam melhorar o valor nutricional e a tolerância a estresses de cana de açúcar. Os diversos componentes do sistema de defesa antioxidante interagem entre si e as suas sínteses devem ser muito bem reguladas. Fatores de transcrição envolvidos na regulação da resposta ao estresse oxidativo de bactérias, leveduras e de humanos diferem consideravelmente entre si e quando foram utilizados para buscas no banco de dados do SUCEST, somente genes com similaridades fracas foram encontrados, sugerindo que estas proteínas não são muito conservadas. O envolvimento de espécies reativas de oxigênio e nitrogênio na defesa de plantas contra patógenos também é discutido neste trabalho. Abstract in english Oxidative stress response in plants is still poorly understood in comparison with the correspondent phenomenon in bacteria, yeast and mammals. For instance, nitric oxide is assumed to play various roles in plants although no nitric oxide synthase gene has yet been isolated. This research reports the results of a search of the sugarcane expressed sequence tag (SUCEST) database for homologous sequences involved in the oxidative stress response. I have not found any gene sim (more) ilar to nitric oxide synthase in the SUCEST database although an alternative pathway for nitric oxide synthesis was proposed. I have also found several genes involved in antioxidant defense, e.g. metal chelators, low molecular weight compounds, antioxidant enzymes and repair systems. Ascorbate (vitamin C) is a key antioxidant in plants because it reaches high concentrations in cells and is a substrate for ascorbate peroxidase, an enzyme that I found in different isoforms in the SUCEST database. I also found many enzymes involved in the biosynthesis of low molecular weight antioxidants, which may be potential targets for genetic manipulation. The engineering of plants for increased vitamin C and E production may lead to improvements in the nutritional value and stress tolerance of sugarcane. The components of the antioxidant defense system interact and their synthesis is probably closely regulated. Transcription factors involved in regulation of the oxidative stress response in bacteria, yeast and mammals differ considerably among themselves and when I used them to search the SUCEST database only genes with weak similarities were found, suggesting that these transcription regulators are not very conserved. The involvement of reactive oxygen species and antioxidants in plant defense against pathogens is also discussed.

Soares Netto, Luis Eduardo

2001-12-01

349

Efficient Chlorophyll Fluorescence Measurements of Sugarcane  

Science.gov (United States)

As with many crops, chlorophyll fluorescence emission is a promising tool for measuring responses of sugarcane (Saccharum spp.) to biotic and abiotic stresses. Chlorophyll fluorescence can be easily measured using portable fluorometers. However, several factors should be considered in order to op...

350

Sugarcane, sugar and ethanol technlogical information  

Energy Technology Data Exchange (ETDEWEB)

This work describes Embrapa's (Brazilian Agricultural Research Corporation) pioneer initiative creating an online service which provides sugarcane, sugar and ethanol technological information. Embrapa has developed software tools for structuring Knowledge Trees, management contents, graphic visualization (hyperbolic tree) and it has also developed its own methodologies for organizing information. The Knowledge Tree is designed in the patterns of the productive chain of sugarcane; the sets of data present the main instructions, recommendations and technologies produced by Brazilian public research institutions. It is intended to offer an ample amount of pertinent and relevant technical information - displayed at Embrapa Information Agency website - to many professionals in the sugarcane sector, especially for producers, students and technical support staff. Moreover, it is expected to contribute to the enhancement of the technology transference process to allow competitive gains in Brazilian agri-business and to socialize knowledge - which is the mission of Embrapa in its business. It is still expected to contribute to the diffusion of technological information and the knowledge of sugarcane for the areas of tropical agriculture around the world.

Souza, M.I.F.; Oliveira, D.R.M.S.; Marin, F.R.; Santos, A.D.; Hanashiro, M.M. [Embrapa Agriculture Informatics, Campinas, SP (Brazil); Vian, C.E.F; Sollero, G.C.; Andrioli, K.G. [Luiz de Queiroz College of Agriculture/University of Sao Paulo, Piracicaba, SP (Brazil)

2008-07-01

351

Studies on Somatic Embryogenesis in Sugarcane  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Somatic embryogenesis was studied in sugarcane cultivars CPF-237 and SPF-213. Explants used were leaves, lateral buds and pith. MS medium along with NAA and 2,4-D in various concentrations were used and it was observed that 1.0 mg NAA and 3-mg/l 2,4-D was optimal for embryogenesis. Leaf portion show...

Farheen Niaz; Azra Quraishi

352

Phenotypic diversity of sugarcane variety germplasm  

Directory of Open Access Journals (Sweden)

Full Text Available Sugarcane varieties are important in providing parental resources in sugarcane breeding programs. In order to improve efficiency in selecting sugarcane varieties as parents, to provide guidance in choosing the best parent combinations for crossing, and to assist in choosing core collections of parents, the genetic variation, genetic structure and relationships of a range of traits were studied in a set of sugarcane varieties from different origins. Seventeen qualitative traits and five quantitative traits were studied, and a range of statistics were determined including genetic variance for each quantitative trait, genetic distance, coefficient of geneticdivergence, and genotypic relationships based on cluster analysis. The coefficient of variance (CV) of all quantitative traits differed among different groups of varieties based on their origins, that population from Hainan Province exhibited the largest genetic diversity. The analysis of genetic diversity of qualitative traitsrevealed that variety populations from the USA, Taiwan of China, and Australia had high levels of genetic diversity in trait values, suggesting there had been greater use of diverse parental materials in programs in those places. Results from analysis of coefficients of genetic divergence (Gst = 0.0479 for quantitative traits, Gst = 0.0950 for qualitative traits) indicated that a high proportion of total genetic variation was retained within the groups of origin, with a high level of overlap in variation between most groups, and the high gene flow (Nm = 4.7632 for qualitative traits, Nm = 9.9493 for quantitative traits) showed the active genetic exchange was found between different origins. Based on analysis of genetic distance, relationship between variety populations from different origins was examined. The genetic distance between origins ranged from 0.0261 to 0.2945, with the greatest similarity being evident in variety populations between Fujian and Guangdong provinces (China), Cuba and USA, Guangxi and Yunnan provinces (China), Australia and Philippines, Jiangxi and Sichuan provinces (China), Brazil and France. This may reflect similarities in ancestors of parents used in these pairs of programs, in particular for the variety populations from Fujian and Guangdong which were the most similar. It is suggested these sugarcane variety populations which possess rich phenotypic diversity should be utilized and those crosses between sugarcane variety populations within the same groups from cluster analysis should be avoided. Sugarcane variety populations from Mexico, which are quite dissimilar to most other groups, should be given a higher priority in breeding programs.

Xinlong Liu; Qing Cai; Caiwen Wu; Li Ma; Xiongmei Ying; Xin Lu; Yuanhong Fan

2010-01-01

353

Isolation of Pythium oligandrum from Egyptian soil and its mycoparasitic effect on Pythium ultimum var. ultimum the damping-off organism of wheat.  

Science.gov (United States)

Pythium oligandrum Drechsler bearing spherical sporangia with complex subglobose elements was isolated for the first time in Egypt from agricultural field soil cultivated with alfalfa (Trifolium alexandrinum) in El-Minia, Egypt. This fungus was found to be an active bio-control agent against P. ultimum var. ultimum, the damping-off organism of wheat. In agar plates, P. oligandrum parasitized P. ultimum var. ultimum hyphae with the aid of thin haustorial branches or infection pegs, eventually leading to host destruction. Incorporation of P. oligandrum into carboxymethylcellulose seed coating successfully eliminated pre-emergence damping-off of wheat caused by P. ultimum var. ultimum, whereas Post-emergence damping-off was prevented by adding inocula of P. oligandrum to the soil. PMID:16284719

Abdelzaher, H M; Elnaghy, M A; Fadl-Allah, E M

1997-01-01

354

Isolation of Pythium oligandrum from Egyptian soil and its mycoparasitic effect on Pythium ultimum var. ultimum the damping-off organism of wheat.  

UK PubMed Central (United Kingdom)

Pythium oligandrum Drechsler bearing spherical sporangia with complex subglobose elements was isolated for the first time in Egypt from agricultural field soil cultivated with alfalfa (Trifolium alexandrinum) in El-Minia, Egypt. This fungus was found to be an active bio-control agent against P. ultimum var. ultimum, the damping-off organism of wheat. In agar plates, P. oligandrum parasitized P. ultimum var. ultimum hyphae with the aid of thin haustorial branches or infection pegs, eventually leading to host destruction. Incorporation of P. oligandrum into carboxymethylcellulose seed coating successfully eliminated pre-emergence damping-off of wheat caused by P. ultimum var. ultimum, whereas Post-emergence damping-off was prevented by adding inocula of P. oligandrum to the soil.

Abdelzaher HM; Elnaghy MA; Fadl-Allah EM

1997-01-01

355

Micropropagation of Two Sugarcane (Saccharum officinarum) Varieties from Callus Culture  

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Full Text Available Protocol for induction of callus and regeneration response of two sugarcane varieties (Isd-16, Isd-28) was established through callus culture using leaf sheath. Multiple shoot regeneration at various frequencies was observed using different concentrations and combinations of growth regulators. The highest percentage of callus induction was observed in the medium containing 3.0 mg l -1 2,4-D with 10% coconut water (CM). The best response in terms of multiple shoot formation was observed that on MS medium supplemented with BAP 1.0 mg l -1 +IBA 0.5 mg l -1. NAA (3.0 mg l -1) was found effective in the production of roots. The variety Isd-16 showed better response than the variety Isd-28 towards shoot multiplication. Seventy percent of the plantlets produced from in vitro culture method survived in the ex vitro condition.

M.Z. Karim; M.N. Amin; M.A. Hossain; S. Islam; Faruk Hossin; R. Alam

2002-01-01

356

Obstrução intestinal por Pythium insidiosum em um cão: relato de caso Intestinal obstruction by Pythium insidiosum in a dog: case report  

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Full Text Available Relata-se um caso de pitiose intestinal em um Husky Siberiano, de um ano de idade, macho atendido em um Hospital Veterinário Escola com sinais de obstrução intestinal. Ao exame físico, notou-se massa cilíndrica na região abdominal cranial, posteriormente confirmada por meio de radiografia e ultrassonografia. Durante a laparotomia exploratória, constatou-se massa extraluminal envolvendo o jejuno e alterações na parede do órgão. Realizou-se a ressecção da porção afetada do intestino e, posteriormente, anastomose. O exame histológico do tecido evidenciou inflamação piogranulomatosa acentuada. Na coloração de prata metenamina de Grocott, hifas septadas foram observadas. O diagnóstico de infecção por Pythium insidiosum foi confirmado por meio da imunoistoquímica. Após a cirurgia, o animal restabeleceu a defecação; no 30° dia pós-cirúrgico, foi relatada ainda presença de diarreia. O tratamento com itraconazol e terbinafina foi instituído durante 60 dias. Após dois anos do procedimento cirúrgico e do tratamento com antifúngicos orais, o cão não apresentou recidiva.A case of intestinal pythiosis in a one-year-old male Siberian Husky treated at a Veterinary School Hospital with signs of intestinal obstruction is reported. At physical examination, a cylindrical mass was palpable in the cranial abdomen, later confirmed by radiography and ultrasonography. During the exploratory laparotomy, it was evidenced an extraluminal mass involving the jejunum and alterations of the wall in the organ. After that, a resection of the affected portion of the intestine was made followed by anastomosis. The histologic examination evidenced accented pyogranulomatous inflammation. By the Grocott methenamine silver stain, branching hyphae were observed. The diagnosis of infection by Pythium insidiosum was confirmed by immunohistochemistry. The animal reestablished the defecation after the surgery; on the 30th postoperative day, it was also reported the presence of diarrhea. The treatment with itraconazol and terbinafina was instituted for 60 days. Two years after the surgical procedure and treatment with oral antifungals, the dog did not show recurrence.

P.S. Hunning; G. Rigon; C.S. Faraco; S.P. Pavarini; D. Sampaio; W. Beheregaray; D. Driemeier

2010-01-01

357

Obstrução intestinal por Pythium insidiosum em um cão: relato de caso/ Intestinal obstruction by Pythium insidiosum in a dog: case report  

Scientific Electronic Library Online (English)

Full Text Available Abstract in portuguese Relata-se um caso de pitiose intestinal em um Husky Siberiano, de um ano de idade, macho atendido em um Hospital Veterinário Escola com sinais de obstrução intestinal. Ao exame físico, notou-se massa cilíndrica na região abdominal cranial, posteriormente confirmada por meio de radiografia e ultrassonografia. Durante a laparotomia exploratória, constatou-se massa extraluminal envolvendo o jejuno e alterações na parede do órgão. Realizou-se a ressecção da porç (more) ão afetada do intestino e, posteriormente, anastomose. O exame histológico do tecido evidenciou inflamação piogranulomatosa acentuada. Na coloração de prata metenamina de Grocott, hifas septadas foram observadas. O diagnóstico de infecção por Pythium insidiosum foi confirmado por meio da imunoistoquímica. Após a cirurgia, o animal restabeleceu a defecação; no 30° dia pós-cirúrgico, foi relatada ainda presença de diarreia. O tratamento com itraconazol e terbinafina foi instituído durante 60 dias. Após dois anos do procedimento cirúrgico e do tratamento com antifúngicos orais, o cão não apresentou recidiva. Abstract in english A case of intestinal pythiosis in a one-year-old male Siberian Husky treated at a Veterinary School Hospital with signs of intestinal obstruction is reported. At physical examination, a cylindrical mass was palpable in the cranial abdomen, later confirmed by radiography and ultrasonography. During the exploratory laparotomy, it was evidenced an extraluminal mass involving the jejunum and alterations of the wall in the organ. After that, a resection of the affected portion (more) of the intestine was made followed by anastomosis. The histologic examination evidenced accented pyogranulomatous inflammation. By the Grocott methenamine silver stain, branching hyphae were observed. The diagnosis of infection by Pythium insidiosum was confirmed by immunohistochemistry. The animal reestablished the defecation after the surgery; on the 30th postoperative day, it was also reported the presence of diarrhea. The treatment with itraconazol and terbinafina was instituted for 60 days. Two years after the surgical procedure and treatment with oral antifungals, the dog did not show recurrence.

Hunning, P.S.; Rigon, G.; Faraco, C.S.; Pavarini, S.P.; Sampaio, D.; Beheregaray, W.; Driemeier, D.

2010-08-01

358

Chemo sterilization of the sugarcane borer Diatraea saccharalis (Fabricius, 1794) (Lepidoptera: Crambidae) with sugar solution bait and insecticides of insect growth regulators group; Esterilizacao quimica da broca da cana-de-acucar Diatraea saccharalis (Fabricius, 1794) (Lepidoptera: Crambidae) atraves de isca com melaco e inseticidas do grupo dos reguladores de crescimento de insetos  

Energy Technology Data Exchange (ETDEWEB)

The sugarcane borer Diatraea saccharalis (Fabricius, 1794) (Lepidoptera: Crambidae) is an important pest in Brazilian sugarcane crops. Currently, biological control is the most frequently used method for controlling D saccharalis. However, in several locations, the parasitoid Cotesia flavipes (Cameron) (Hymenoptera: Braconidae) has not been effective for controlling this pest, and it has been recorded infestation intensity above 25%. In this context, the Sterile Insect Technique could be an additional control method in Integrated Pest Management, because it is compatible with other control methods. The use of insecticides that interferes in hormone homeostasis involved in the ecdyse's process with exogenous hormone sources or synthetic analogues (agonists or antagonists) can result in the interruption of the reproductive process or abnormal development of the insect?s embryo. Then, the objective of this study was to evaluate the insecticides that regulates the insect growth on the D. saccharalis reproduction. The insecticides tested were: chlorfluazuron (1,0 and 1,5 g a.i./L), diflubenzuron (3,75; 5,0 and 7,5 g a.i./L), flufenoxuron (1,0 g a.i./L), lufenuron (0,75; 1,0 and 2,0 g a.i./L), novaluron (0,5 and 1,0 g a.i./L) pyriproxyfen (1,0; 1,5; 1,8 and 2,0 g a.i./L) and teflubenzuron (1,5; 3,0 and 6,0 g a.i./L). Each insecticide was provided to 1-day moths on soaked cotton with a sugar solution at 10% as a bait. All treatments, except to of the lowest concentration of lufenuron (0,75 g a.i./L) decreased the egg production in relation to the control. Flufenoxuron (1,00 g g a.i./L) and chlorfluazuron (1,50 g a.i./L) decreased the lifespan of both sexes treated by ingestion. Lufenuron (2,0 g a.i./L), novaluron (1,0 g a.i./L) and teflubenzuron (3,0 g a.i./L) decreased the male's lifespan. The most effective treatments for sterilization were pyriproxyfen (1,8 g a.i./L and 2,0 g a.i./L) and lufenuron (2,0 g a.i./L), witch showed efficiencies greater or close to 80%. (author)

Sazaki, Catia Sumie Shimatai. E-mail csazaki@yahoo.com.br

2006-07-01

359

Evaluation of transgenic Bacillus thuringiensis corn hybrids against Cry1Ab-susceptible and -resistant sugarcane borer (Lepidoptera: Crambidae).  

Science.gov (United States)

A Louisiana strain of the sugarcane borer, Diatraea saccharalis (F.) (Lepidoptera: Crambidae), was selected for resistance to the CrylAb protein of Bacillus thuringiensis (Bt) by using an F2 screening procedure. Survival of Bt-resistant, -susceptible, and -heterozygous genotypes of sugarcane borer was evaluated on vegetative and reproductive stages of five non-Bt and seven Bt field corn, Zea mays L., hybrids in a greenhouse study. Larval survival was recorded 21 d after infestation of neonates on potted plants. Larval survival across the three sugarcane borer genotypes and five non-Bt corn hybrids after 21 d ranged from 23.6 +/- 5.2% (mean +/- SEM) to 57.5 +/- 5.2%. Mean survival of Cry1Ab-resistant larvae on vegetative and reproductive plant stages was 12 and 21%, respectively. During the vegetative stages, all seven Bt corn hybrids were highly efficacious against Cry1Ab-susceptible and -heterozygous genotypes of sugarcane borer, with a larval survival rate of <2% for the Bt-susceptible genotype and < or =5% for the heterozygotes. However, 8-18% of the heterozygous genotype survived on reproductive stage plants for four of the seven Bt corn hybrids tested. The variation in performance of Bt corn cultivars at vegetative and reproductive growth stages against Cry1Ab resistant sugarcane borer suggests differential seasonal expression that may hasten resistance in the field. Bt corn hybrids expressing a "high dose" for European corn borer, Ostrinia nubilalis (Hübner), may not produce a sufficient high dose for the sugarcane borer. PMID:18232406

Wu, Xiaoyi; Huang, Fangneng; Leonard, B Rogers; Moore, Steven H

2007-12-01

360

Control of Chinese-kale damping-off caused by Pythium aphanidermatum by antifungal metabolites of Trichoderma virens  

Directory of Open Access Journals (Sweden)

Full Text Available Seven strains of Trichoderma virens were isolated from Chinese-kale planting soil in Nakhon Si Thammarat province. Efficacy of those isolates to inhibit mycelial growth and overgrow on mycelia ofPythium aphanidermatum, a causal agent of damping-off on Chinese-kale, were determined by a dual culture test. All strains significantly inhibited growth and overgrew on mycelia of P. aphanidermatum on potato dextrose agar (PDA) as compared with the control. Strains T-NST-01, T-NST-05 and T-NST-07 gave high values of inhibition by 85.5, 82.5 and 78.5%, respectively. For efficacy to overgrow on mycelia of pathogen test, strains T-NST-05, T-NST-07 and T-NST-01 provided 48.3, 47.0 and 46.1% of mycelial overgrowth, respectively. Antifungal metabolites were extracted from three promising strains and tested against mycelial growth and sporangium production of P. aphanidermatum. The results showed that 1,000 mg/L of all metabolites completely inhibited mycelial growth and sporangium production. Under laboratory condition, all metabolites (1,000 mg/L) significantly increased the number of Chinese-kale seedling germination, especially the metabolites from T-NST-01 and T-NST-07 provided germination of 92.5 and 87.5%, respectively. Under glasshouse conditions, Chinese-kale seedlings treated with 1,000 mg/L of metabolites from strains T-NST-01 and T-NST-07 survived by 90.5 and 87.5%, respectively, while the control 1 (sterile water) and control 2 (2% methanol) had 19.0 and 18.5% of survived seedlings, respectively. In P. aphanidermatum viability test, mycelia of P. aphanidermatum treated with antifungal metabolites from three strains of T. virens showed no visible growth, while the control with 2% methanol or sterile water, mycelia of P. aphanidermatum rapidly grew and covered whole surface of PDA in of the Petri dish within 4 days.

Warin Intana; Chiradej Chamswarng

2007-01-01

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