Do rice water weevils and rice stem borers compete when sharing a host plant?*

Science.gov (United States)

Shi, Sheng-wei; He, Yan; Ji, Xiang-hua; Jiang, Ming-xing; Cheng, Jia-an

2008-01-01

The rice water weevil (RWW) Lissorhoptrus oryzophilus Kuschel (Coleoptera: Curculionidae) is an invasive insect pest of rice Oryza sativa L. in China. Little is known about the interactions of this weevil with indigenous herbivores. In the present study, adult feeding and population density of the weevil, injury level of striped stem borer Chilo suppressalis (Walker) (Lepidoptera: Pyralidae) and pink stem borer Sesamia inferens (Walker) (Lepidoptera: Noctuidae) to rice, as well as growth status of their host plants were surveyed in a rice field located in Southeastern Zhejiang, China, in 2004 with the objective to discover interspecific interactions on the rice. At tillering stage, both adult feeding of the weevil and injury of the stem borers tended to occur on larger tillers (bearing 5 leaves) compared with small tillers (bearing 2~4 leaves), but the insects showed no evident competition with each other. At booting stage, the stem borers caused more withering/dead hearts and the weevil reached a higher density on the plants which had more productive tillers and larger root system; the number of weevils per tiller correlated negatively with the percentage of withering/dead hearts of plants in a hill. These observations indicate that interspecific interactions exist between the rice water weevil and the rice stem borers with negative relations occurring at booting or earlier developmental stages of rice. PMID:18600788

N transfer in three species grass-clover mixtures with chicory, ribwort plantain or caraway

DEFF Research Database (Denmark)

Dhamala, Nawa Raj; Rasmussen, Jim; Carlsson, Georg

2017-01-01

Background and aimsThere is substantial evidence that legume-derived Nitrogen (N) is transferred to neighboring non-legumes in grassland mixtures. However, there is sparse information about how deep rooted non-legume forage herbs (forbs) influence N transfer in multi-species grasslands. Methodology......Red clover (Trifolium pretense L.) was grown together with perennial ryegrass (Lolium perenne L.) and one of three forb species: chicory (Cichorium intybus L.), ribwort plantain (Plantago lanceolata L.) or caraway (Carum carvi L.) in a field experiment. During the first year after the establishment, red...... clover leaves were labeled with 15N-urea to determine the N transfer from red clover to companion ryegrass and forbs. ResultsOn an annual basis, up to 15 % of red clover N was transferred to the companion ryegrass and forbs, but predominantly to the grass. The forb species did not differ in their ability...

Crystal Structure of Green Fluorescent Protein Clover and Design of Clover-Based Redox Sensors.

Science.gov (United States)

Campbell, Benjamin C; Petsko, Gregory A; Liu, Ce Feng

2018-02-06

We have determined the crystal structure of Clover, one of the brightest fluorescent proteins, and found that its T203H/S65G mutations relative to wild-type GFP lock the critical E222 side chain in a fixed configuration that mimics the major conformer of that in EGFP. The resulting equilibrium shift to the predominantly deprotonated chromophore increases the extinction coefficient (EC), opposes photoactivation, and is responsible for the bathochromic shift. Clover's brightness can further be attributed to a π-π stacking interaction between H203 and the chromophore. Consistent with these observations, the Clover G65S mutant reversed the equilibrium shift, dramatically decreased the EC, and made Clover photoactivatable under conditions that activated photoactivatable GFP. Using the Clover structure, we rationally engineered a non-photoactivatable redox sensor, roClover1, and determined its structure as well as that of its parental template, roClover0.1. These high-resolution structures provide deeper insights into structure-function relationships in GFPs and may aid the development of excitation-improved ratiometric biosensors. Copyright © 2017 Elsevier Ltd. All rights reserved.

Fold distributions at clover, crystal and segment levels for segmented clover detectors

International Nuclear Information System (INIS)

Kshetri, R; Bhattacharya, P

2014-01-01

Fold distributions at clover, crystal and segment levels have been extracted for an array of segmented clover detectors for various gamma energies. A simple analysis of the results based on a model independant approach has been presented. For the first time, the clover fold distribution of an array and associated array addback factor have been extracted. We have calculated the percentages of the number of crystals and segments that fire for a full energy peak event

Effects of entomopathogenic fungus species, and impact of fertilizers, on biological control of pecan weevil (Coleoptera: Curculionidae).

Science.gov (United States)

Shapiro-Ilan, David I; Gardner, Wayne A; Wells, Lenny; Cottrell, Ted E; Behle, Robert W; Wood, Bruce W

2013-04-01

The pecan weevil, Curculio caryae (Horn), is a key pest of pecan, Carya illinoinensis (Wangenh.) K. Koch. Prior research indicated the potential for use of Hypocreales fungi to suppress C. caryae. We compared the efficacy of two fungal spp., Beauveria bassiana (GHA strain) and Metarhizium brunneum (F52), in their ability to cause C. caryae mortality. The fungus, B. bassiana, was applied to trunks of pecan trees (a method previously shown to be effective in C. caryae suppression) and efficacy was compared with M. brunneum applied to the ground or to the trunk with or without SoyScreen Oil as an ultraviolet protecting agent. Results indicated B. bassiana to be superior to M. brunneum regardless of application method; consequently, the potential for applying B. bassiana to control C. caryae was explored further. Specifically, the impact of different fertilizer regimes (as used by pecan growers) on the persistence of B. bassiana (GHA) in soil was determined. B. bassiana was applied to soil in a pecan orchard after one of several fertilizer treatments--i.e., ammonium nitrate, crimson clover, poultry litter, clover plus poultry litter, and a no-fertilizer control. B. bassiana persistence up to 49 d in 2009 and 2010 was assessed by plating soil onto selective media and determining the number of colony forming units, and by baiting soil with a susceptible host, Galleria mellonella (L.). Fertilizer treatments did not impact B. bassiana persistence. We conclude that standard fertilizers for nitrogen management, when applied according to recommended practices, are unlikely to negatively impact survival of B. bassiana in pecan orchards when the fungus is applied for C. caryae suppression during weevil emergence. Additional research on interactions between entomopathogenic fungi and fertilizer amendments (or other tree nutrition or soil management practices) is merited.

Investigation of Amino Acids As Herbicides for Control of Orobanche minor Parasitism in Red Clover.

Science.gov (United States)

Fernández-Aparicio, Mónica; Bernard, Alexandre; Falchetto, Laurent; Marget, Pascal; Chauvel, Bruno; Steinberg, Christian; Morris, Cindy E; Gibot-Leclerc, Stephanie; Boari, Angela; Vurro, Maurizio; Bohan, David A; Sands, David C; Reboud, Xavier

2017-01-01

Certain amino acids induce inhibitory effects in plant growth due to feedback inhibition of metabolic pathways. The inhibition patterns depend on plant species and the plant developmental stage. Those amino acids with inhibitory action on specific weeds could be utilized as herbicides, however, their use for weed control has not been put into practice. Orobanche minor is a weed that parasitizes red clover. O. minor germination is stimulated by clover root exudates. The subsequent seedling is an obligated parasite that must attach quickly to the clover root to withdraw its nutrients. Early development of O. minor is vulnerable to amino acid inhibition and therefore, a series of in vitro , rhizotron, and field experiments were conducted to investigate the potential of amino acids to inhibit O. minor parasitism. In in vitro experiments it was found that among a collection of 20 protein amino acids, lysine, methionine and tryptophan strongly interfere with O. minor early development. Field research confirmed their inhibitory effect but revealed that methionine was more effective than lysine and tryptophan, and that two successive methionine applications at 308 and 543 growing degree days inhibited O. minor emergence in red clover up to 67%. We investigated additional effects with potential to influence the practical use of amino acids against broomrape weeds, whether the herbicidal effect may be reversible by other amino acids exuded by host plants or may be amplified by inducing host resistance barriers against O. minor penetration. This paper suggests that amino acids may have the potential to be integrated into biorational programs of broomrape management.

Investigation of Amino Acids As Herbicides for Control of Orobanche minor Parasitism in Red Clover

Directory of Open Access Journals (Sweden)

Mónica Fernández-Aparicio

2017-05-01

Full Text Available Certain amino acids induce inhibitory effects in plant growth due to feedback inhibition of metabolic pathways. The inhibition patterns depend on plant species and the plant developmental stage. Those amino acids with inhibitory action on specific weeds could be utilized as herbicides, however, their use for weed control has not been put into practice. Orobanche minor is a weed that parasitizes red clover. O. minor germination is stimulated by clover root exudates. The subsequent seedling is an obligated parasite that must attach quickly to the clover root to withdraw its nutrients. Early development of O. minor is vulnerable to amino acid inhibition and therefore, a series of in vitro, rhizotron, and field experiments were conducted to investigate the potential of amino acids to inhibit O. minor parasitism. In in vitro experiments it was found that among a collection of 20 protein amino acids, lysine, methionine and tryptophan strongly interfere with O. minor early development. Field research confirmed their inhibitory effect but revealed that methionine was more effective than lysine and tryptophan, and that two successive methionine applications at 308 and 543 growing degree days inhibited O. minor emergence in red clover up to 67%. We investigated additional effects with potential to influence the practical use of amino acids against broomrape weeds, whether the herbicidal effect may be reversible by other amino acids exuded by host plants or may be amplified by inducing host resistance barriers against O. minor penetration. This paper suggests that amino acids may have the potential to be integrated into biorational programs of broomrape management.

Effects of Titanium Dioxide Nanoparticles on Red Clover and Its Rhizobial Symbiont.

Science.gov (United States)

Moll, Janine; Okupnik, Annette; Gogos, Alexander; Knauer, Katja; Bucheli, Thomas D; van der Heijden, Marcel G A; Widmer, Franco

2016-01-01

Titanium dioxide nanoparticles (TiO2 NPs) are in consideration to be used in plant protection products. Before these products can be placed on the market, ecotoxicological tests have to be performed. In this study, the nitrogen fixing bacterium Rhizobium trifolii and red clover were exposed to two TiO2 NPs, i.e., P25, E171 and a non-nanomaterial TiO2. Growth of both organisms individually and their symbiotic root nodulation were investigated in liquid and hydroponic systems. While 23 and 18 mg l-1 of E171 and non-nanomaterial TiO2 decreased the growth rate of R. trifolii by 43 and 23% respectively, P25 did not cause effects. Shoot length of red clover decreased between 41 and 62% for all tested TiO2 NPs. In 21% of the TiO2 NP treated plants, no nodules were found. At high concentrations certain TiO2 NPs impaired R. trifolii as well as red clover growth and their symbiosis in the hydroponic systems.

Effects of Titanium Dioxide Nanoparticles on Red Clover and Its Rhizobial Symbiont.

Directory of Open Access Journals (Sweden)

Janine Moll

Full Text Available Titanium dioxide nanoparticles (TiO2 NPs are in consideration to be used in plant protection products. Before these products can be placed on the market, ecotoxicological tests have to be performed. In this study, the nitrogen fixing bacterium Rhizobium trifolii and red clover were exposed to two TiO2 NPs, i.e., P25, E171 and a non-nanomaterial TiO2. Growth of both organisms individually and their symbiotic root nodulation were investigated in liquid and hydroponic systems. While 23 and 18 mg l-1 of E171 and non-nanomaterial TiO2 decreased the growth rate of R. trifolii by 43 and 23% respectively, P25 did not cause effects. Shoot length of red clover decreased between 41 and 62% for all tested TiO2 NPs. In 21% of the TiO2 NP treated plants, no nodules were found. At high concentrations certain TiO2 NPs impaired R. trifolii as well as red clover growth and their symbiosis in the hydroponic systems.

Relationships between Nitrate and Oxygen Supply in Symbiotic Nitrogen Fixation by White Clover

DEFF Research Database (Denmark)

Minchin, F. R.; Ines Minguez, M.; Sheedy, J. E.

1986-01-01

Exposure of mature, nodulated plants of white clover (Trifolium repens) cv. Blanca to 330 mg dm−3 NO3-N for 8 d caused nitrogenase activity per plant to decrease by 80%. Total nodulated root respiration was not significantly affected but analysis of its components showed an 81% decrease in nitrog...

Effect of red clover on the microbial transformation of phenanthrene and octadecane in the soil

Science.gov (United States)

Nazarov, A. V.; Shestakova, E. A.; Anan'yina, L. N.

2017-08-01

The influence of red clover ( Trifolium pratense L.) plants on the decomposition of phenanthrene and octadecane in the soil has been studied. Effect of plant root mass on the abundance of hydrocarbondegrading bacteria, the composition of their communities, and the degradation of hydrocarbons in the soil has been revealed. Changes in the taxonomic composition of hydrocarbon-degrading bacteria under the effect of red clover are characterized by an increase in the abundance of species from the genera Acinetobacter, Kaistia, Novosphingobium, Pseudomonas, and Xanthomonas. A positive effect of the studied microbial-plant association on the degradation of octadecane and especially phenanthrene in the soil has been revealed.

Do boll weevils really diapause?

Science.gov (United States)

Boll weevil, Anthonomus grandis grandis Boheman, diapause has been poorly understood since the term was first used 50 yrs ago to describe the pest’s winter dormancy in temperate regions. This literature-based study found that low temperature and changes in photoperiod are the boll weevil diapause-i...

Arbuscular mycorrhiza enhanced arsenic resistance of both white clover (Trifolium repens Linn.) and ryegrass (Lolium perenne L.) plants in an arsenic-contaminated soil

Energy Technology Data Exchange (ETDEWEB)

Dong Yan; Zhu Yongguan [Department of Soil Environmental Science, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China); Smith, F. Andrew [Soil and Land Systems, School of Earth and Environmental Sciences, Waite Campus, University of Adelaide, Adelaide, SA 5005 (Australia); Wang Youshan [Institute of Plant Nutrition and Resources, Beijing Academy of Agriculture and Forestry, Beijing 100089 (China); Chen Baodong [Department of Soil Environmental Science, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085 (China)], E-mail: bdchen@rcees.ac.cn

2008-09-15

In a compartmented cultivation system, white clover (Trifolium repens Linn.) and ryegrass (Lolium perenne L.), with their roots freely intermingled, or separated by 37 {mu}m nylon mesh or plastic board, were grown together in an arsenic (As) contaminated soil. The influence of AM inoculation on plant growth, As uptake, phosphorus (P) nutrition, and plant competitions were investigated. Results showed that both plant species highly depended on mycorrhizas for surviving the As contamination. Mycorrhizal inoculation substantially improved plant P nutrition, and in contrast markedly decreased root to shoot As translocation and shoot As concentrations. It also showed that mycorrhizas affected the competition between the two co-existing plant species, preferentially benefiting the clover plants in term of nutrient acquisition and biomass production. Based on the present study, the role of AM fungi in plant adaptation to As contamination, and their potential use for ecological restoration of As contaminated soils are discussed. - Both white clover and ryegrass highly depend on the mycorrhizal associations for surviving heavy arsenic contamination.

Arbuscular mycorrhiza enhanced arsenic resistance of both white clover (Trifolium repens Linn.) and ryegrass (Lolium perenne L.) plants in an arsenic-contaminated soil

International Nuclear Information System (INIS)

Dong Yan; Zhu Yongguan; Smith, F. Andrew; Wang Youshan; Chen Baodong

2008-01-01

In a compartmented cultivation system, white clover (Trifolium repens Linn.) and ryegrass (Lolium perenne L.), with their roots freely intermingled, or separated by 37 μm nylon mesh or plastic board, were grown together in an arsenic (As) contaminated soil. The influence of AM inoculation on plant growth, As uptake, phosphorus (P) nutrition, and plant competitions were investigated. Results showed that both plant species highly depended on mycorrhizas for surviving the As contamination. Mycorrhizal inoculation substantially improved plant P nutrition, and in contrast markedly decreased root to shoot As translocation and shoot As concentrations. It also showed that mycorrhizas affected the competition between the two co-existing plant species, preferentially benefiting the clover plants in term of nutrient acquisition and biomass production. Based on the present study, the role of AM fungi in plant adaptation to As contamination, and their potential use for ecological restoration of As contaminated soils are discussed. - Both white clover and ryegrass highly depend on the mycorrhizal associations for surviving heavy arsenic contamination

Effect of Pseudomonas fluorescens and pyoverdine on the phytoextraction of cesium by red clover in soil pots and hydroponics.

Science.gov (United States)

Hazotte, Alice; Péron, Olivier; Gaudin, Pierre; Abdelouas, Abdesselam; Lebeau, Thierry

2018-05-12

With the aim of improving the phytoextraction rate of cesium (Cs), the effect of Pseudomonas fluorescens ATCC 17400 and its siderophore pyoverdine (PVD) on the uptake of Cs by red clover was studied in soil pots. This work also provides a mechanistic understanding of the Cs-bacteria (or PVD)-illite-plant interactions by using a simplified experimental design, i.e., hydroponics with either Cs in solution or Cs-spiked illite in suspension. For soil spiked with 11.2 mmol kg -1 (1480 mg kg -1 ) of Cs, 0.43% of total Cs was taken up by red clover in 12 days (119 μmol g -1 (16 mg g -1 ) of Cs dry matter in roots and 40 μmol g -1 (5 mg g -1 ) in shoots). In hydroponics with Cs in solution (0.1 mmol L -1 or 13 mg L -1 ), 75% of Cs was taken up vs. only 0.86% with Cs-spiked illite suspension. P. fluorescens and PVD did not increase Cs concentrations in aboveground parts and roots of red clover and even decreased them. The damaging effect of PVD on red clover growth was demonstrated with the biomass yielding 66% of the control in soil pots (and 100% mortality after 12 days of exposition) and only 56% in hydroponics (78% with illite in suspension). Nonetheless, PVD and, to a lesser extent, P. fluorescens increased the translocation factor up to a factor of 2.8. This study clearly showed a direct damaging effect of PVD and to a lower extent the retention of Cs by biofilm covering both the roots and illite, both resulting in the lower phytoextraction efficiency.

Early interspecific interference in the wheat/faba bean (Triticum aestivum/ Vicia faba ssp. minor and rapeseed/squarrosum clover (Brassica napus var. oleifera/Trifolium squarrosum intercrops

Directory of Open Access Journals (Sweden)

Paolo Benincasa

2012-04-01

Full Text Available Most of research on intercrops evaluate performances and interference between species on the basis of final yield, while little knowledge is available on the interference in early stages and at the root level, at least for cultivated intercrops. In fact, in the few studies on this subject species are often combined minding at experimental needs (e.g. common substrate, temperature and water requirements, easy root separation more than at their actual use in the farm. The present work evaluates interspecific interference during early developmental stages for two intercrops of agricultural interest: soft wheat-faba bean and rapeseed-squarrosum clover. Improving this knowledge would help intercrop growth modelling and rational cultivation. The experiments were carried out on soft wheat (Triticum aestivum, faba bean (Vicia faba var. minor, rapeseed (Brassica napus var. oleifera and squarrosum clover (Trifolium squarrosum, germinated and grown until 32 days after sowing (DAS as one-species stands or as wheat/faba bean and rapeseed/squarrosum clover intercrops, with different densities and proportions for the two species in each couple. Germination was studied in controlled-temperature chamber, plantlet growth was studied on pots in the greenhouse. During germination no interspecific interference was observed for both wheat/faba bean and rapeseed/squarrosum clover intercrops. During plantlet growth, interspecific interference occurred in both intercrops causing variations in whole plant and root dry matter accumulation. In the wheat/faba bean intercrop each species suffered from the competitive effect of the companion species and faba bean was the dominant species when present in lower proportion than wheat. The unexpectedly high aggressivity of faba bean may be explained either with the greater seed size that could have represented an initial advantage within the short duration of the experiment or with the competition towards wheat for substrate N

Production of N2O in grass-clover pastures

International Nuclear Information System (INIS)

Carter, M.S.

2005-09-01

Agricultural soils are known to be a considerable source of the strong greenhouse gas nitrous oxide (N 2 O), and in soil N 2 O is mainly produced by nitrifying and denitrifying bacteria. In Denmark, grass-clover pastures are an important component of the cropping system in organic as well as conventional dairy farming, and on a European scale grass-clover mixtures represent a large part of the grazed grasslands. Biological dinitrogen (N 2 ) fixation in clover provides a major N input to these systems, but knowledge is sparse regarding the amount of fixed N 2 lost from the grasslands as N2O. Furthermore, urine patches deposited by grazing cattle are known to be hot-spots of N 2 O emission, but the mechanisms involved in the N 2 O production in urine-affected soil are very complex and not well understood. The aim of this Ph.D. project was to increase the knowledge of the biological and physical-chemical mechanisms, which control the production of N2O in grazed grass-clover pastures. Three experimental studies were conducted with the objectives of: 1: assessing the contribution of recently fixed N 2 as a source of N 2 O. 2: examining the link between N 2 O emission and carbon mineralization in urine patches. 3: investigating the effect of urine on the rates and N 2 O loss ratios of nitrification and denitrification, and evaluating the impact of the chemical conditions that arise in urine affected soil. The results revealed that only 3.2 ± 0.5 ppm of the recently fixed N 2 was emitted as N2O on a daily basis. Thus, recently fixed N released via easily degradable clover residues appears to be a minor source of N2O. Furthermore, increased N 2 O emission following urine application at rates up to 5.5 g N m -2 was not caused by enhanced denitrification stimulated by labile compounds released from scorched plant roots. Finally, the increase of soil pH and ammonium following urine application led to raised nitrification rate, which appeared to be the most important factor

Boll weevil invasion process in Argentina

Science.gov (United States)

The boll weevil, Anthonomus grandis grandis Boheman, is the most destructive cotton pest in the Western Hemisphere. In 1993, the pest was reported in Argentina, and in 1994 boll weevils were captured in cotton fields in the Formosa Province on the border between Argentina and Paraguay. The pest ha...

The protection of the poppy plant (Papaver somniferum L. against poppy weevil (Stenocarus ruficornis Stephens by foliar application

Directory of Open Access Journals (Sweden)

Karel Sikora

2008-01-01

Full Text Available Poppy seed (Papaver somniferum L. is an annual autumn or spring plant. This crop is cultivated generally for seed which is used as a foodstuff in food processing industry. The biological efficacy of different tested active ingredients (lambda-cyhalothrin, bifenthrin, aplha-cypermethrin, DE-225 and combination chlorpyrifos + cypermethrin on poppy weevil (Stenocarus ruficornis S. was evaluated in comparison with reference active ingredient (carbofuran used as a standard treatment. The active ingredients were applied against the mentioned pest once in the season and were used in doses which were similar to those used against stem weevils in winter oil seed rape. Reference active ingredient was used in the dose which was authorised in the Czech Republic as standard ones against the poppy weevil. All active ingredients revealed efficacy which was measured (as a size of injuries both on leaves and roots. Two trials were performed in 2001–2002 in which efficacy and selectivity were assessed.

Laboratory and field evaluation of sterile male boll weevil competitiveness

International Nuclear Information System (INIS)

McGovern, W.L.

1976-01-01

The production of pheromone by boll weevils, Anthonomus grandis Boheman, treated with 10,000 rad of CO-60 gamma irradiation compared favorably with that of control weevils for 5 days; however, feeding (determined by frass collection) was reduced from the first day post-treatment. No direct correlation was found between production of pheromone and elimination of frass. Overwintered male boll weevils were found to produce small quantities of pheromone and the ratio of components was less attractive at the same concentration as the standard laboratory formulation of grandlure. Most healthy sterilized male weevils should be more attractive than overwintered males. Laboratory-reared sterilized male boll weevils can be as attractive to female weevils as overwintered field males. Weevils treated with busulfan (1,4-butanediol dimethanesulfonate) alone were more attractive than those treated with combinations of busulfan and hempa. In general, sterilization reduced the attractiveness of laboratory males by about 50 percent. Evidence is presented for the existence of ''super-males.''

Preliminary Results of Clover and Grass Coverage and Total Dry Matter Estimation in Clover-Grass Crops Using Image Analysis

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Anders K. Mortensen

2017-12-01

Full Text Available The clover-grass ratio is an important factor in composing feed ratios for livestock. Cameras in the field allow the user to estimate the clover-grass ratio using image analysis; however, current methods assume the total dry matter is known. This paper presents the preliminary results of an image analysis method for non-destructively estimating the total dry matter of clover-grass. The presented method includes three steps: (1 classification of image illumination using a histogram of the difference in excess green and excess red; (2 segmentation of clover and grass using edge detection and morphology; and (3 estimation of total dry matter using grass coverage derived from the segmentation and climate parameters. The method was developed and evaluated on images captured in a clover-grass plot experiment during the spring growing season. The preliminary results are promising and show a high correlation between the image-based total dry matter estimate and the harvested dry matter ( R 2 = 0.93 with an RMSE of 210 kg ha − 1 .

White clover regenerative ability under N fertilizing and grazing

Directory of Open Access Journals (Sweden)

Josip Leto

2008-12-01

Full Text Available Recently, ecological and economic factors in milk and meat production stimulate use of legumes and grass-legumes mixtures, with zero or minimum mineral N as alternative to grass monoculture with high rate of mineral N. Research objective was to examine the effect of N application (0-N0 and 150 kg ha-1 year-1-N150 and rotational grazing by cattle (C and sheep (S on white clover: growing points number, stolon lenght, stolon dry weight, dry matter yield and clover contribution to total annual herbage production. N150 significantly reduced the growing points number, stolon length and stolon dry weight for more than 70 % compared to N0. Grazing treatment affected stolon population density only in interaction with N application because of N150 significantly reduced white clover population density only in sheep grazing. S-treatment had higher clover DM yield (0.21 t ha-1 than C-treatment (0.13 t ha-1. N0 had higher clover DM yield (0.25 t ha-1 than N150 (0.09 t ha-1. However, the interaction grazing management x N rate was significant for clover DM yield and clover contribution to total DM yield. N150 reduced both parameters for 80 % only in sheep grazing while difference in DM yield and clover contribution to total DM yield between grazing treatment was recorded only in N0 Sheep grazing increased DM yield for 150 % and clover contribution for 99 % compared to cattle grazing.

Phenoloxidase and melanization test for mango seed weevil

International Nuclear Information System (INIS)

Heather, N.W.

1999-01-01

This project was initiated to determine whether the phenoloxidase test successfully developed for fruit flies would be applicable to mango seed weevil, Sternochetus mangiferae (Fabricius). Mango seed weevil represents a quarantine impediment to the entry of mangoes to mainland USA and some other countries. It is not a destructive pest and rarely causes fruit damage even in late maturing varieties in which adults can emerge from ripe fruit. The main problem with the weevils come from nursery propagators who are concerned about possible effects on germination. It is questionable whether this is adequate justification for the level of quarantine importance with which this pest is currently regarded. It should not be confused with the mango pulp weevil Sternochetus frigidus Fabricius which does damage all infested fruit. (author)

Olfactory cues are subordinate to visual stimuli in a neotropical generalist weevil.

Directory of Open Access Journals (Sweden)

Fernando Otálora-Luna

Full Text Available The tropical root weevil Diaprepes abbreviatus is a major pest of multiple crops in the Caribbean Islands and has become a serious constraint to citrus production in the United States. Recent work has identified host and conspecific volatiles that mediate host- and mate-finding by D. abbreviatus. The interaction of light, color, and odors has not been studied in this species. The responses of male and female D. abbreviatus to narrow bandwidths of visible light emitted by LEDs offered alone and in combination with olfactory stimuli were studied in a specially-designed multiple choice arena combined with a locomotion compensator. Weevils were more attracted to wavelengths close to green and yellow compared with blue or ultraviolet, but preferred red and darkness over green. Additionally, dim green light was preferred over brighter green. Adult weevils were also attracted to the odor of its citrus host + conspecifics. However, the attractiveness of citrus + conspecific odors disappeared in the presence of a green light. Photic stimulation induced males but not females to increase their speed. In the presence of light emitted by LEDs, turning speed decreased and path straightness increased, indicating that weevils tended to walk less tortuously. Diaprepes abbreviatus showed a hierarchy between chemo- and photo-taxis in the series of experiments presented herein, where the presence of the green light abolished upwind anemotaxis elicited by the pheromone + host plant odor. Insight into the strong responses to visual stimuli of chemically stimulated insects may be provided when the amount of information supplied by vision and olfaction is compared, as the information transmission capacity of compound eyes is estimated to be several orders of magnitude higher compared with the olfactory system. Subordination of olfactory responses by photic stimuli should be considered in the design of strategies aimed at management of such insects.

X-ray CT in the detection of palm weevils

International Nuclear Information System (INIS)

Ma, A.K.W.; Alghamdi, A.A.; Spyrou, N.M.

2012-01-01

Early detection of the red palm weevils (RPW) is a major challenge in agriculture among all kinds of palm trees due to the nature of the insect and the difficulty to trace them through their life stages associated with the tree life. Many methods have been applied for the weevil detection such as X-ray diffraction techniques, fluoroscopy and ultrasound. On the other hand, the idea of tomography has been used for other purposes such as the determination of the age of the tree and for applied environmental studies. Such technology can also reveal the weevil in principle. In this study, we explore the use of X-ray CT for weevil detection with the Monte Carlo method. A model of the stem of a palm tree is developed for simulations. MCNPX is chosen to carry out the simulations for the radiography tally in the code. The tally records the 2D data of the X-ray beams irradiating the tree model. An iterative reconstruction method for cone beam CT is applied to obtain the 3D slices of the tree model. We are exploring the minimum number of projection angles and the detectability of the weevil. We shall also report the sensitivity of weevil detection using X-ray CT with a large set of simulations with different weevil sizes and tree diameters. (author)

Measurements on a prototype segmented Clover detector

CERN Document Server

Shepherd, S L; Cullen, D M; Appelbe, D E; Simpson, J; Gerl, J; Kaspar, M; Kleinböhl, A; Peter, I; Rejmund, M; Schaffner, H; Schlegel, C; France, G D

1999-01-01

The performance of a segmented Clover germanium detector has been measured. The segmented Clover detector is a composite germanium detector, consisting of four individual germanium crystals in the configuration of a four-leaf Clover, housed in a single cryostat. Each crystal is electrically segmented on its outer surface into four quadrants, with separate energy read-outs from nine crystal zones. Signals are also taken from the inner contact of each crystal. This effectively produces a detector with 16 active elements. One of the purposes of this segmentation is to improve the overall spectral resolution when detecting gamma radiation emitted following a nuclear reaction, by minimising Doppler broadening caused by the opening angle subtended by each detector element. Results of the tests with sources and in beam will be presented. The improved granularity of the detector also leads to an improved isolated hit probability compared with an unsegmented Clover detector. (author)

Pine weevil (Hylobius abietis) antifeedants from lodgepole pine (Pinus contorta).

Science.gov (United States)

Bratt, K; Sunnerheim, K; Nordenhem, H; Nordlander, G; Langström, B

2001-11-01

Pine weevils (Hylobius abietis) fed less on bark of lodgepole pine (Pinus contorta) than on bark of Scots pine (P. sylvestris). Two pine weevil antifeedants, ethyl trans-cinnamate and ethyl 2,3-dibromo-3-phenyl-propanoate, were isolated from bark of lodgepole pine. These two compounds significantly reduced pine weevil feeding in a laboratory bioassay. In field assays, the second compound significantly decreased pine weevil damage on planted seedlings. Ethyl 2,3-dibromo-3-phenylpropanoate has not previously been reported as a natural product.

Eradication of sweet potato weevil using Co-60 gamma radiation

International Nuclear Information System (INIS)

Tokunaga, Taizo

2007-01-01

Sweet potato weevil which is a harmful insect injuring sweet potatoes was found out at Yoron Island in 1915 for the first time in Kagoshima prefecture, Japan. Here the eradication of sweet potato weevils using cobalt 60 irradiation achieved at Kikai Island is described. The mass-reared male weevils in potatoes are in pasture after sterilized by gamma irradiation. If the sexually sterile male copulates with a wild female, the egg does not incubate. By the repeated sterilization during several generations, the eradication of sweet potato weevils was accomplished. (M.H.)

A model for long-distance dispersal of boll weevils (Coleoptera: Curculionidae)

Science.gov (United States)

Westbrook, John K.; Eyster, Ritchie S.; Allen, Charles T.

2011-07-01

The boll weevil, Anthonomus grandis (Boheman), has been a major insect pest of cotton production in the US, accounting for yield losses and control costs on the order of several billion US dollars since the introduction of the pest in 1892. Boll weevil eradication programs have eliminated reproducing populations in nearly 94%, and progressed toward eradication within the remaining 6%, of cotton production areas. However, the ability of weevils to disperse and reinfest eradicated zones threatens to undermine the previous investment toward eradication of this pest. In this study, the HYSPLIT atmospheric dispersion model was used to simulate daily wind-aided dispersal of weevils from the Lower Rio Grande Valley (LRGV) of southern Texas and northeastern Mexico. Simulated weevil dispersal was compared with weekly capture of weevils in pheromone traps along highway trap lines between the LRGV and the South Texas / Winter Garden zone of the Texas Boll Weevil Eradication Program. A logistic regression model was fit to the probability of capturing at least one weevil in individual pheromone traps relative to specific values of simulated weevil dispersal, which resulted in 60.4% concordance, 21.3% discordance, and 18.3% ties in estimating captures and non-captures. During the first full year of active eradication with widespread insecticide applications in 2006, the dispersal model accurately estimated 71.8%, erroneously estimated 12.5%, and tied 15.7% of capture and non-capture events. Model simulations provide a temporal risk assessment over large areas of weevil reinfestation resulting from dispersal by prevailing winds. Eradication program managers can use the model risk assessment information to effectively schedule and target enhanced trapping, crop scouting, and insecticide applications.

Predicting Dry Matter Composition of Clover Grass Leys Using Data Simulation and Camera-based Segmentation of Field Canopies into White Clover, Red Clover, Grass and Weeds

DEFF Research Database (Denmark)

Skovsen, Søren; Dyrmann, Mads; Eriksen, Jørgen

2018-01-01

species in the biomass. In our setup, we exploit the top-down canopy view of the clover grass ley to estimate the volumetric composition of the yield, and predict the composition of the dry matter of the forage. Using a deep learning approach, the canopy image is automatically pixel-wise segmented....... The biggest hindrance to training a fully convolutional deep neural network is the requirement of labeled data. Due to the complexity, the high number of leaves and high levels of occlusions in clover grass canopies, hand labeling the data requires roughly 20 hours of manual labor per image. The need...... for hundreds or thousands labeled training images renders this approach unfeasible. We have shown that implementation of image simulation of distinct clover grass fields can reduce the labeling task significantly. Investing less than 20 hours of labor, thousands of simulated images and corresponding labels can...

Modeling of clover detector in addback mode

Science.gov (United States)

Kshetri, R.

2012-07-01

Based on absorption and scattering of gamma-rays, a formalism has been presented for modeling the clover germanium detector in addback mode and to predict its response for high energy γ-rays. In the present formalism, the operation of a bare clover detector could be described in terms of three quantities only. Considering an additional parameter, the formalism could be extended for suppressed clover. Using experimental data on relative single crystal efficiency and addback factor as input, the peak-to-total ratio has been calculated for three energies (Eγ = 3.401, 5.324 and 10.430 MeV) where direct measurement of peak-to-total ratio is impossible due to absence of a radioactive source having single monoenergetic gamma-ray of that energy. The experimental validation and consistency of the formalism have been shown considering data for TIGRESS clover detector. In a recent work (R. Kshetri, JINST 2012 7 P04008), we showed that for a given γ-ray energy, the formalism could be used to predict the peak-to-total ratio as a function of number of detector modules. In the present paper, we have shown that for a given composite detector (clover detector is considered here), the formalism could be used to predict the peak-to-total ratio as a function of γ-ray energy.

Modeling of clover detector in addback mode

International Nuclear Information System (INIS)

Kshetri, R

2012-01-01

Based on absorption and scattering of gamma-rays, a formalism has been presented for modeling the clover germanium detector in addback mode and to predict its response for high energy γ-rays. In the present formalism, the operation of a bare clover detector could be described in terms of three quantities only. Considering an additional parameter, the formalism could be extended for suppressed clover. Using experimental data on relative single crystal efficiency and addback factor as input, the peak-to-total ratio has been calculated for three energies (E γ = 3.401, 5.324 and 10.430 MeV) where direct measurement of peak-to-total ratio is impossible due to absence of a radioactive source having single monoenergetic gamma-ray of that energy. The experimental validation and consistency of the formalism have been shown considering data for TIGRESS clover detector. In a recent work (R. Kshetri, JINST 2012 7 P04008), we showed that for a given γ-ray energy, the formalism could be used to predict the peak-to-total ratio as a function of number of detector modules. In the present paper, we have shown that for a given composite detector (clover detector is considered here), the formalism could be used to predict the peak-to-total ratio as a function of γ-ray energy.

Phenylphenalenones Accumulate in Plant Tissues of Two Banana Cultivars in Response to Herbivory by the Banana Weevil and Banana Stem Weevil.

Science.gov (United States)

Hölscher, Dirk; Buerkert, Andreas; Schneider, Bernd

2016-08-25

Phenylphenalenone-type compounds accumulated in the tissues of two banana cultivars-Musa acuminata cv. "Grande Naine" (AAA) and Musa acuminata × balbisiana Colla cv. "Bluggoe" (ABB)-when these were fed on by the banana weevil (Cosmopolites sordidus (Germ.) (Coleoptera: Curculionidae)) and the banana stem weevil (Odoiporus longicollis (Oliver) (Coleoptera: Curculionidae)). The chemical constituents of the banana material were separated by means of chromatographic techniques and identified by NMR spectroscopy. One new compound, 2-methoxy-4-phenylphenalen-1-one, was found exclusively in the corm material of "Bluggoe" that had been fed on by the weevils.

Medium-term response of microbial community to rhizodeposits of white clover and ryegrass and tracing of active processes induced by 13C and 15N labelled exudates

DEFF Research Database (Denmark)

Kusliene, Gedrime; Rasmussen, Jim; Kuzyakov, Yakov

2014-01-01

and actinomycetes was unaffected by plant species, but pool of Gram-negative and Gram-positive bacteria was greater under white clover at the 10 percent significance level. In the short term, microorganisms more actively utilised fresh exudates (13C-labelled) of ryegrass than of white clover. We expected ryegrass...... microbial groups in soil under white clover (Trifolium repens L.) and ryegrass (Lolium perenne L.) following leaf-labelling with 13C-bicarbonate and 15N-urea. In this way microbial N and 15N and the composition of PLFAs reflect the medium-term (two months) response of microorganisms to rhizodeposits......, whereas the 13C-label of the PLFAs reflects the short-term (one week) utilisation of root exudates following labelling of shoots. In the medium term, microbial biomass N and 15N were greater under the ryegrass, whereas total PLFA was higher under white clover. The relative abundance of fungi...

A study of the wet deposit and foliar uptake of iodine and strontium on rye-grass and clover

International Nuclear Information System (INIS)

Angeletti, Livio; Levi, Emilio; Commission of the European Communities, Ispra

1977-12-01

Foliar uptake of iodine and strontium by rye-grass and clover was studied as a function of aspersion intensities. At the same time, the contribution of root sorption to foliar uptake was measured. The effective half-lives of radionuclides of standing and harvested grass were also determined together with their uptake under the action of demineralized water aspersion [fr

Complementary effects of red clover inclusion in ryegrass-white clover swards for grazing and cutting

DEFF Research Database (Denmark)

Eriksen, Jørgen; Askegaard, Margrethe; Søegaard, Karen

2014-01-01

Increasing plant species diversity in grasslands may improve productivity and stability of yields. In a field experiment, we investigated the herbage dry-matter (DM) yield and crude protein content of two-species swards of perennial ryegrass–white clover (Lolium perenne L.–Trifolium repens L...... clover in sown swards are discussed. These may include higher nitrogen-use efficiency in ruminants, increased soil fertility and improved sward flexibility to cope with changing managements. The findings also suggest positive yield effects of alternating between cutting and grazing within the season...

The beneficial effect of dual inoculation of vesicular-arbuscular mycorrhizae + rhizobium on growth of white clover

Directory of Open Access Journals (Sweden)

Lin, XG.

1993-01-01

Full Text Available Investigation on the effect of phosphorus on vesicular-arbuscular mycorrhizal infection, and dual inoculation of vesicular-arbuscular mycorrhizae + rhizobium on growth of white clover under field microplots and pot experiments was conducted on fluvo-aquic soils of semi-arid region in north China. The results showed that 60 kg P205 ha in form of superphosphate was the most favorable phosphorus level for vesicular-arbuscular mycorrhizal infection ; mycorrhizal infection, nodulation, dry weight of shoots and roots, total uptake of nitrogen, phosphorus and other elements, the final yields and recovery of phosphorus of white clover were significantly increased by vesicular-arbuscular mycorrhizal inoculation and dual inoculation with vesicular-arbuscular mycorrhizal fungi and rhizobium. The highest response of inoculation was obtained by adding fertilizer phosphorus at the level of 60 kg P205 ha in form of superphosphate.

A first principle approach for clover detector

Science.gov (United States)

Kshetri, R.

2012-08-01

A simple model based on probability flow arguments has been presented for understanding the clover germanium detector. Using basic concepts of absorption and scattering of gamma-rays, the operation of the clover detector has been described in terms of six probability amplitudes and a parameter. Instead of using an empirical method or simulation, this work presents the first attempt to calculate the peak-to-total and peak-to-background ratios of the clover detector using experimental data of relative single crystal efficiency and addback factor as an input. A unique feature of our approach is that these ratios could be calculated for energies where their direct measurement is impossible due to absence of a radioactive source having single monoenergetic gamma-ray of that energy. Results for four gamma-ray energies (Eγ = 1.408, 3.907, 7.029 and 10.430 MeV) have been discussed. Agreement between experimental data and analysis results has been observed. The present approach could describe clover-type detectors as well. As an example, the nine element detector has been considered. We have demonstrated that our formalism can describe both finite and infinite interactions of γ-rays with the clover crystals. The work presented in this paper follows similar philosophy as presented in a recent paper (R. Kshetri, JInst 2012 7 P04008), which deals with modeling of encapsulated type composite detectors like miniball, cluster and SPI (Spectrometer for INTEGRAL satellite).

A first principle approach for clover detector

International Nuclear Information System (INIS)

Kshetri, R

2012-01-01

A simple model based on probability flow arguments has been presented for understanding the clover germanium detector. Using basic concepts of absorption and scattering of gamma-rays, the operation of the clover detector has been described in terms of six probability amplitudes and a parameter. Instead of using an empirical method or simulation, this work presents the first attempt to calculate the peak-to-total and peak-to-background ratios of the clover detector using experimental data of relative single crystal efficiency and addback factor as an input. A unique feature of our approach is that these ratios could be calculated for energies where their direct measurement is impossible due to absence of a radioactive source having single monoenergetic gamma-ray of that energy. Results for four gamma-ray energies (E γ = 1.408, 3.907, 7.029 and 10.430 MeV) have been discussed. Agreement between experimental data and analysis results has been observed. The present approach could describe clover-type detectors as well. As an example, the nine element detector has been considered. We have demonstrated that our formalism can describe both finite and infinite interactions of γ-rays with the clover crystals. The work presented in this paper follows similar philosophy as presented in a recent paper (R. Kshetri, JInst 2012 7 P04008), which deals with modeling of encapsulated type composite detectors like miniball, cluster and SPI (Spectrometer for INTEGRAL satellite).

Phenylphenalenones Accumulate in Plant Tissues of Two Banana Cultivars in Response to Herbivory by the Banana Weevil and Banana Stem Weevil

Directory of Open Access Journals (Sweden)

Dirk Hölscher

2016-08-01

Full Text Available Phenylphenalenone-type compounds accumulated in the tissues of two banana cultivars—Musa acuminata cv. “Grande Naine” (AAA and Musa acuminata × balbisiana Colla cv. “Bluggoe” (ABB—when these were fed on by the banana weevil (Cosmopolites sordidus (Germ. (Coleoptera: Curculionidae and the banana stem weevil (Odoiporus longicollis (Oliver (Coleoptera: Curculionidae. The chemical constituents of the banana material were separated by means of chromatographic techniques and identified by NMR spectroscopy. One new compound, 2-methoxy-4-phenylphenalen-1-one, was found exclusively in the corm material of “Bluggoe” that had been fed on by the weevils.

Molecular diagnostic for boll weevil (Coleoptera: Curculionidae) based on amplification of three species-specific microsatellites.

Science.gov (United States)

Kim, Kyung Seok; Szendrei, Zsofia; Rodriguez-Saona, Cesar; Mulder, Phillip G; Sappington, Thomas W

2009-04-01

The boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), is a serious pest of cultivated cotton, Gossypium hirsutum L., in the Americas, and reinfestation of zones from which they have been eradicated is of perpetual concern. Extensive arrays of pheromone traps monitor for reintroductions, but occasionally the traps collect nontarget weevils that can be misidentified by scouts. For example, the congeneric pepper weevil, Anthonomus eugenii Cano, and other superficially similar weevils are attracted to components of the boll weevil lure or trap color. Although morphologically distinguishable by trained personnel, the potential for misidentification is compounded when captured weevils are dismembered or partially consumed by ants or ground beetles that sometimes feed on them in the traps. Because misidentification can have expensive consequences, a molecular diagnostic tool would be of great value to eradication managers. We demonstrate that a cocktail of three primer pairs in a single polymerase chain reaction (PCR) amplify species-specific microsatellites that unambiguously distinguish the boll weevil from three other weevil species tested, including pepper weevil; cranberry weevil, Anthonomus eugenii musculus Say; and pecan weevil, Curculio caryae Horn. However, it does not distinguish the boll weevil from the subspecific "thurberia" weevil. A universal internal transcribed spacer primer pair included in the cocktail cross-amplifies DNA from all species, serving as a positive control. Furthermore, the diagnostic primers amplified the target microsatellites from various boll weevil adult body parts, indicating that the PCR technology using the primer cocktail is sensitive enough to positively identify a boll weevil even when the body is partly degraded.

Production of N{sub 2}O in grass-clover pastures

Energy Technology Data Exchange (ETDEWEB)

Carter, M.S.

2005-09-01

Agricultural soils are known to be a considerable source of the strong greenhouse gas nitrous oxide (N{sub 2}O), and in soil N{sub 2}O is mainly produced by nitrifying and denitrifying bacteria. In Denmark, grass-clover pastures are an important component of the cropping system in organic as well as conventional dairy farming, and on a European scale grass-clover mixtures represent a large part of the grazed grasslands. Biological dinitrogen (N{sub 2}) fixation in clover provides a major N input to these systems, but knowledge is sparse regarding the amount of fixed N{sub 2} lost from the grasslands as N2O. Furthermore, urine patches deposited by grazing cattle are known to be hot-spots of N{sub 2}O emission, but the mechanisms involved in the N{sub 2}O production in urine-affected soil are very complex and not well understood. The aim of this Ph.D. project was to increase the knowledge of the biological and physical-chemical mechanisms, which control the production of N2O in grazed grass-clover pastures. Three experimental studies were conducted with the objectives of: 1: assessing the contribution of recently fixed N{sub 2} as a source of N{sub 2}O. 2: examining the link between N{sub 2}O emission and carbon mineralization in urine patches. 3: investigating the effect of urine on the rates and N{sub 2}O loss ratios of nitrification and denitrification, and evaluating the impact of the chemical conditions that arise in urine affected soil. The results revealed that only 3.2 {+-} 0.5 ppm of the recently fixed N{sub 2} was emitted as N2O on a daily basis. Thus, recently fixed N released via easily degradable clover residues appears to be a minor source of N2O. Furthermore, increased N{sub 2}O emission following urine application at rates up to 5.5 g N m{sup -2} was not caused by enhanced denitrification stimulated by labile compounds released from scorched plant roots. Finally, the increase of soil pH and ammonium following urine application led to raised

Effects of elevated temperature and CO2 on aboveground-belowground systems: a case study with plants, their mutualistic bacteria and root / shoot herbivores

Directory of Open Access Journals (Sweden)

James Michael William Ryalls

2013-11-01

Full Text Available Interactions between above- and belowground herbivores have been prominent in the field of aboveground-belowground ecology from the outset, although little is known about how climate change affects these organisms when they share the same plant. Additionally, the interactive effects of multiple factors associated with climate change such as elevated temperature (eT and elevated atmospheric carbon dioxide (eCO2 are untested. We investigated how eT and eCO2 affected larval development of the lucerne weevil (Sitona discoideus and colonisation by the pea aphid (Acyrthosiphon pisum, on three cultivars of a common host plant, lucerne (Medicago sativa. Sitona discoideus larvae feed on root nodules housing N2-fixing rhizobial bacteria, allowing us to test the effects of eT and eCO2 on three trophic levels. Moreover, we assessed the influence of these factors on plant growth. eT increased plant growth rate initially (6, 8 and 10 weeks after sowing, with cultivar ‘Sequel’ achieving the greatest height. Inoculation with aphids, however, reduced plant growth at week 14. eT severely reduced root nodulation by 43%, whereas eCO2 promoted nodulation by 56%, but only at ambient temperatures. Weevil presence increased net root biomass and nodulation, by 31 and 45%, respectively, showing an overcompensatory plant growth response. Effects of eT and eCO2 on root nodulation were mirrored by weevil larval development; eT and eCO2 reduced and increased larval development, respectively. Contrary to expectations, aphid colonisation was unaffected by eT or eCO2, but there was a near-significant 10% reduction in colonisation rates on plants with weevils present belowground. The contrasting effects of eT and eCO2 on weevils potentially occurred through changes in root nodulation patterns.

Edge effect on weevils and spiders

OpenAIRE

Horváth, R.; Magura, T.; Péter, G.; Tóthmérész, B.

2002-01-01

The edge effect on weevils and spiders was tested along oak forest – meadow transects using sweep-net samples at the Síkfökút Project in Hungary. For spiders the species richness was significantly higher in the forest edge than either in the meadow or the forest interior. For weevils the species richness of the forest edge was higher than that of the meadow, but the difference was not statistically significant whereas the species richness of the forest...

Non-perturbative improvement of stout-smeared three flavour clover fermions

Energy Technology Data Exchange (ETDEWEB)

Cundy, N.; Goeckeler, M. [Regensburg Univ. (Germany). Inst. fuer Theoretische Physik; Horsley, R. [Edinburgh Univ. (GB). School of Physics and Astronomy] (and others)

2009-01-15

We discuss a 3-flavour lattice QCD action with clover improvement in which the fermion matrix has single level stout smearing for the hopping terms together with unsmeared links for the clover term. With the (tree-level) Symanzik improved gluon action this constitutes the Stout Link Non-perturbative Clover or SLiNC action. To cancel O(a) terms the clover term coefficient has to be tuned. We present here results of a non-perturbative determination of this coefficient using the Schroedinger functional and as a by-product a determination of the critical hopping parameter. Comparisons of the results are made with lowest order perturbation theory. (orig.)

Alfalfa weevil male: effect of γ-radiation and weevil age on mating competitiveness and sperm transfer

International Nuclear Information System (INIS)

Wollam, J.D.; Hower, A.A. Jr.

1977-01-01

Virgin male Hypera postica (Gyllenhal) were irradiated at 1, 2, 3, 4, and 5 weeks of age. Alfalfa weevils from each age group were subjected to γ-radiation doses of 0, 2, 3, 4, 5, and 6 krads. Mating competitiveness was reduced by the 5 to 6 krad doses in all age groups except those 4 weeks old. Weevils irradiated at 1 week of age showed a reduction in competitiveness at doses above 2 krad. Radiation dose and age at irradiation had little noticeable effect on sperm transfer

Edge effect on weevils and spiders

Directory of Open Access Journals (Sweden)

R. Horváth

2002-05-01

Full Text Available The edge effect on weevils and spiders was tested along oak forest – meadow transects using sweep-net samples at the Síkfökút Project in Hungary. For spiders the species richness was significantly higher in the forest edge than either in the meadow or the forest interior. For weevils the species richness of the forest edge was higher than that of the meadow, but the difference was not statistically significant whereas the species richness of the forest interior was significantly lower than that of the forest edge and the meadow. The composition of the spider assemblage of the edge was more similar to the forest, while the composition of weevils in the edge was more similar to the meadow. Our results based on two invertebrate groups operating on different trophic levels suggest that there is a significant edge effect for the studied taxa resulting in higher species richness in the edge.

Impact on Clover-Grass Yield from Wheel Load and Tyre Pressure

DEFF Research Database (Denmark)

Green, Ole; Jørgensen, Rasmus Nyholm; Sørensen, Claus Aage Grøn

2009-01-01

Traffic intensities have been shown to have a negative influence on the yield of grass and clover. A full scale grass-clover field trial was established to estimate the effect on clover-grass yields as a function of different wheel loads and tire pressures. The trial comprised 16 different traffi...

Comparisons of boll weevil (Coleoptera: Curculionidae) pheromone traps with and without kill strips.

Science.gov (United States)

Suh, C P C; Armstrong, J S; Spurgeon, D W; Duke, S

2009-02-01

Boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), eradication programs typically equip pheromone traps with an insecticide-impregnated kill strip. These strips are intended to kill captured insects, thereby simplifying trap servicing and reducing the loss of weevils from predation and escape. However, the effectiveness of kill strips has not been extensively evaluated. We examined the influences of kill strips on weevil captures, trap servicing, and the incidences of weevil predation and trap obstruction (e.g., by spider webs). Evaluations were conducted weekly during three different production periods (pre- to early-, late-, and postseason) of cotton, Gossypium hirsutum L., to represent different environmental conditions and weevil population levels. Within each period, mean weekly captures of weevils in traps with and without kill strips were statistically similar. On average, traps with kill strips took 9 s longer to service than traps without kill strips, but statistical differences were only detected during the late-season period. Overall, the mean weekly proportion of traps with evidence of weevil predation or trap obstruction was significantly lower for traps with kill strips (0.25) than for traps without kill strips (0.37). However, this reduction in the frequency of weevil predation or trap obstruction was too small to produce a corresponding increase in the numbers of weevils captured. In light of these findings, the use of kill strips is likely unnecessary in eradication programs, but may be a consideration in situations when the numbers of deployed traps are reduced and chronic problems with weevil predation or trap obstruction exist.

Selective breeding for increased pheromone production in the boll weevil (Coleoptera: Curculionidae)

International Nuclear Information System (INIS)

McCoy, J.R.; Wright, J.E.

1990-01-01

The male boll weevil, Anthonomus grandis grandis Boheman, uses an aggregating pheromone to attract females, after which mating often occurs. Sterile boll weevil release programs depend upon this phenomenon to produce sterile matings with feral females. In an effort to increase the effectiveness of the individual sterile male and thereby reduce the number of sterile males required per hectare, a selective-breeding system was used to increase the total pheromone produced by individual male boll weevils. This breeding program increased the total pheromone production by individual male boll weevils to 4.5 times that of the parent population. After irradiation-induced sterilization, there remained 2.2 times more pheromone produced by the selected strain. Therefore, these sterile weevils should be about 2.2 times more attractive to feral females than the parent weevils now in use, and they have the potential to reduce the number of sterile males required in a sterile release program

Sources of N2O in organic grass-clover pastures

OpenAIRE

Ambus, P.

2002-01-01

Organic farming practises, and in particular dairy production systems based on grass-clover pastures are becoming increasingly abundant within Danish agriculture. Grass-clover pastures may provide a mitigation option to reduce grassland nitrous oxide (N2O) emissions (Velthof et al. 1998). The objectives of this work was to examine the relationship between N2O emissions and transformations of inorganic N in organically managed grass-clover pastures of different ages. Results from the projec...

Application of various technological processes in red clover seed processing

OpenAIRE

Đokić, Dragoslav; Stanisavljević, Rade; Terzić, Dragan; Marković, Jordan; Radivojević, Gordana; Anđelković, Bojan; Barać, Saša

2012-01-01

This paper presents the results of the processing of natural red clover seed on the processing equipment using different technological methods. Red clover seed, for the establishment and crop utilization, must be of high purity, germination, and high genetic values. These requirements are achieved by processing, or removing impurities and poor quality seeds. Red clover seed processing involves a number of operations, of which the most important are: cleaning, packaging, labeling and storage. ...

The influence of phosphorus deficiency on growth and nitrogen fixation of white clover plants

OpenAIRE

Høgh-Jensen, Dr Henning; Schjoerring, Dr Jan K.; Soussana, Dr Jean-Francois

2002-01-01

The effects of P deficiency on growth, N2‐fixation and photosynthesis in white clover (Trifolium repens L.) plants were investigated using three contrasting relative addition rates of P, or following abrupt withdrawal of the P supply. Responses to a constant below‐optimum P supply rate consisted of a decline in N2‐fixation per unit root weight and a small reduction in the efficiency with which electrons were allocated to the reduction of N2 in nodules. Abrupt removal of P arrested nodule grow...

Pine weevil feeding in Scots pine and Norway spruce regenerations

OpenAIRE

Wallertz, Kristina

2009-01-01

Damage caused by the pine weevil, Hylobius abietis (L) feeding on conifer seedlings is a major problem in reforested areas in many parts of Europe. The adult weevil feeds on the stem-bark of young seedlings, frequently killing a large proportion of newly planted seedlings. The aims of the studies underlying this thesis were to investigate whether additional food supplies could decrease the damage caused by pine weevil to seedlings, and to determine whether access to extra food might explain w...

Response of banana hybrids to the banana weevil (Cosmopolites ...

African Journals Online (AJOL)

ACSS

Response of banana hybrids to the banana weevil (Cosmopolites sordidus Germar) .... A number of physical and chemical factors are .... The total number of weevils trapped were then counted and recorded. Agronomic characteristics. Bunch weight, girth and height. In addition to corm damage assesment, data was also ...

Collection of pheromone from atmosphere surrounding boll weevils,Anthonomus grandis.

Science.gov (United States)

Chang, J F; Benedict, J H; Payne, T L; Camp, B J; Vinson, S B

1989-02-01

An effluvial method was developed to collect the pheromone, grandlure from actively calling male boll weevils,Anthonomus grandis Boheman. The adsorbant, Porapak Q (ethylvinylbenzene-divinylbenzene), was utilized to trap and concentrate the pheromone. Captured pheromone was desorbed from columns packed with Porapak Q by elution withn-pentane and quantified by capillary column gas-liquid chromatography. In recovery studies with known amounts of synthetic grandlure, we found that the amount of each pheromone component collected was a function of collection duration, elution volume, and initial concentration. This effluvial method was capable of recovering as much as 94.9% of a known quantity (80 μg) of grandlure. The chromatograms were free of extraneous peaks. In studies of insect-produced pheromone, the effluvial method was used to collect pheromone from the air space surrounding male boll weevils as they fed on flower buds from CAMD-E cotton. The quantity and quality of boll-weevil-produced pheromone was determined for days 6, 8, 10, 11, 12, 13, and 14 of boll weevil adulthood. The maximum quantity of natural pheromone was produced on day 13 (4.2 μg/weevil) with a pheromone component ratio of 2.41∶2.29∶0.95∶1 for components I, II, III, and IV, respectively. The effluvial method described in this report is an efficient method to collect and quantify boll weevil pheromone from the atmosphere surrounding actively calling insects. Other applications of this method are suggested.

Specific activity isolation and determination of radioactive Estrogenic Substances in White Clover

International Nuclear Information System (INIS)

Pupiales T, G.; Mejia M, G.

1986-01-01

Due to high number of leguminous that exhibit estrogenic activity, subterranean clover between others, which causes infertility in sheep that eat it. It has been considered that white clover (Trifolium repens, variety Ladino, is an specie of low estrogenic activity, however at Bogota City (Colombia) it has high estrogenic activity and may cause reduction in the dairy cattle fertility. Research done in the IAN (today Ingeominas) over this clover variety, showed that the radioactivity substances presents in the white clover have high activity for stradiol, affecting organs from mouse females; Isoflavonoids from vegetables have an anabolism and utero tropic action; estrogenic activity of clover leaves, was exponentially proportional to the amount of ultraviolet radioactivity, falling upon plants during leaves development stage

Response of banana cultivars to banana weevil attack | Kiggundu ...

African Journals Online (AJOL)

East African Highland Bananas (EAHB) (Musa AAA, 'Matooke' group) are a major staple food in the East African region. However, banana weevil (Cosmopolites sorllidus) is a major production constraint to bananas and may cause damage levels of up to 100%. Pesticides can effectively control banana weevil but these are ...

Fate in Soil of Flavonoids Released from White Clover (Trifolium repens L.)

DEFF Research Database (Denmark)

Carlsen, Sandra C. K.; Pedersen, Hans A.; Spliid, Niels H.

2012-01-01

the presence in soil of bioactive secondary metabolites from clover has received limited attention. In this paper we examine for the first time the release of flavonoids both from field-grown white clover and from soil-incorporated white clover plants of flavonoids, as analyzed by LC-MS/MS. The dominant...... flavonoid aglycones were formononetin, medicarpin, and kaempferol. Soil-incorporated white clover plants generated high concentrations of the glycosides kaempferol-Rha-Xyl-Gal and quercetin-Xyl-Gal. Substantial amounts of kaempferol persisted in the soil for days while the other compounds were degraded...

Boll weevil eradication: a model for sea lamprey control?

Science.gov (United States)

Smith, James W.; Swink, William D.

2003-01-01

Invasions of boll weevil (Anthonomus grandis) into the United States and sea lamprey (Petromyzon marinus) into the Great Lakes were similar in many ways. Important species (American cotton, Gossypium hirsutum, and lake trout, Salvelinus namaycush) and the industries they supported were negatively affected. Initial control efforts were unsuccessful until pesticides and application technologies were developed. For boll weevils, controls relying on pesticides evolved into an integrated program that included recommended farming practices and poisoned baits. However, the discovery of a boll weevil sex pheromone in 1964 allowed adoption of an ongoing program of eradication. Despite opposition over concept and cost, insecticides, pheromone traps, poisoned baits, and approved farming practices were used to eradicate boll weevils from Virginia, North Carolina, South Carolina, Georgia, Florida, and Alabama by 1999. Using the working back approach along the path of the original invasion, eradication was nearly completed by 2002 in Mississippi and eradication programs were underway in Arkansas, Tennessee, Oklahoma, Louisiana, and parts of Texas. Insecticide use for cotton production decreased 50 to 90%, and cotton yields and farm income increased an average of 78 kg/ha and $190 U.S./ha in areas where boll weevils were eradicated. For sea lampreys, integrated management uses lampricides, barriers to migration, trapping, and release of sterilized males. Although sea lamprey eradication is not currently feasible, recent research on larval and sex pheromones might provide the tools to make it possible. A successful eradication program for sea lampreys starting in Lake Superior and expanding to the lower Great Lakes would ultimately provide huge ecological and economic benefits by eliminating lampricide applications, removing barriers that block teleost fishes, and facilitating the recovery of lake trout. Should the opportunity arise, the concept of sea lamprey eradication should

Reduction in clover-grass yield caused by different traffic intensities

DEFF Research Database (Denmark)

Green, Ole; Jørgensen, Rasmus Nyholm; Kristensen, Kristian

Different traffic intensities have been shown to have a negative influence on the yield of grass and clover. A full scale grass-clover field trial was established to estimate the effect on clover-grass yields as a function of different wheel loads and tire pressures. The trial comprised 16...... close to the north, south and east border of the field. No significant interactions were found between the timing of crop and soil damage as affected by wheel load and tire pressure. However, at specific times, there was a significant effect of wheel load and secondary by the tire pressure. At all...... measurement times, the yield was lower using a wheel load of 4745 kg than for a wheel load of 2865 kg.     Key words (for Electronic Reference Library) Traffic intensities, tire load/pressure, clover/grass, yield loss, ...

Diapause in the Boll Weevil (Coleopetra: Curculionidae) : Life-Stage Sensitivity to Enviromental Cues

Science.gov (United States)

Terence L. Wagner; Eric J. Villavaso; Jefferey L. Willers

1999-01-01

This study examines the diapause response in naturally occurring boll weevils under field and simulated field environments of north Mississippi. Squares containing early-stage weevils were collected in July, August, and September and subsamples from each group were installed into similar dynamic environments in the laboratory. In this manner, some weevils experienced...

Phenylphenalenones Accumulate in Plant Tissues of Two Banana Cultivars in Response to Herbivory by the Banana Weevil and Banana Stem Weevil

OpenAIRE

H?lscher, Dirk; Buerkert, Andreas; Schneider, Bernd

2016-01-01

Phenylphenalenone-type compounds accumulated in the tissues of two banana cultivars—Musa acuminata cv. “Grande Naine” (AAA) and Musa acuminata × balbisiana Colla cv. “Bluggoe” (ABB)—when these were fed on by the banana weevil (Cosmopolites sordidus (Germ.) (Coleoptera: Curculionidae)) and the banana stem weevil (Odoiporus longicollis (Oliver) (Coleoptera: Curculionidae)). The chemical constituents of the banana material were separated by means of chromatographic techniques and identified by N...

Effects of oil sands effluent on cattail and clover: photosynthesis and the level of stress proteins

Energy Technology Data Exchange (ETDEWEB)

Crowe, A.U.; Han, B.; Kermode, A.R.; Bendell-Young, L.I.; Plant, A.L. [Simon Fraser University, Burnaby (Canada). Dept. of Biological Sciences

2001-07-01

The oil sands industry located in northeastern Alberta, Canada, generates large volumes of effluent characterized by a high level of dissolved ions and naphthenic acids. The dikes used to store the effluent seep, creating wetlands which are subsequently invaded by obligate wetland flora such as cattail (Typha latifolia L.). The appearance of these wetlands prompted the oil sands industry to consider wetlands as part of their reclamation strategy. However, to ensure long-term viability of such wetlands, the response of the flora to the industrial effluent needed to be determined. To this end, apparent photosynthesis (APS), the level of ribulose-1,5-bisphosphate carboxylase (RuBisCo) large subunit, dehydrin-related polypeptides, and protein disulphide isomerase (PDI) were evaluated in cattail and alsike clover plants (Trifolium hybridum L.) exposed to the oil sands effluent. APS measured in plants impacted by oil sands effluent was significantly higher than that of plants in the non-impacted off-site location. Among the on-site locations, plants growing in the natural wetlands site had higher APS compared to all other sites. The level of RuBisCo was not increased in cattail or clover growing in effluent-contaminated sites indicating that enhanced photosynthesis was not due to greater levels of this enzyme. Dehydrin-related polypeptides were detected only in the roots of cattail and were absent in clover. The polypeptide profile was altered in cattail exposed to oil sands effluent indicating that they were responding to an osmotic stress. The level of PDI was unaffected in the leaves of cattail regardless of the nature of the effluent to which they were exposed. Overall, the data indicate that cattail and clover are adapted to the oil sands effluent, although further studies are needed to assess their long-term ability to survive in the presence of this anthropogenic stress. (Author)

A semiochemical-based push-pull management strategy for pepper weevil

Science.gov (United States)

The pepper weevil Anthonomus eugeenii is a serious pest on peppers in southern United States. The weevils lay their eggs in flower buds and immature fruit where the larvae feed on the developing seed. Consequently, infestations are hard to control by pesticide applications. The aggregation pheromo...

Polygalacturonase from Sitophilus oryzae: Possible horizontal transfer of a pectinase gene from fungi to weevils

Directory of Open Access Journals (Sweden)

Zhicheng Shen

2003-08-01

Full Text Available Endo-polygalacturonase, one of the group of enzymes known collectively as pectinases, is widely distributed in bacteria, plants and fungi. The enzyme has also been found in several weevil species and a few other insects, such as aphids, but not in Drosophila melanogaster, Anopheles gambiae, or Caenorhabditis elegans or, as far as is known, in any more primitive animal species. What, then, is the genetic origin of the polygalacturonases in weevils? Since some weevil species harbor symbiotic microorganisms, it has been suggested, reasonably, that the symbionts' genomes of both aphids and weevils, rather than the insects' genomes, could encode polygalacturonase. We report here the cloning of a cDNA that encodes endo-polygalacturonase in the rice weevil, Sitophilus oryzae (L., and investigations based on the cloned cDNA. Our results, which include analysis of genes in antibiotic-treated rice weevils, indicate that the enzyme is, in fact, encoded by the insect genome. Given the apparent absence of the gene in much of the rest of the animal kingdom, it is therefore likely that the rice weevil polygalacturonase gene was incorporated into the weevil's genome by horizontal transfer, possibly from a fungus.

Fractionated vs acute irradiation: the effects of treating adult boll weevils (Coleoptera: Curculionidae) at different ages

International Nuclear Information System (INIS)

Haynes, J.W.; Wright, J.E.; Mattix, E.

1979-01-01

When 6-7 days old mass-reared ebony boll weevils, Anthonomus grandis Boheman, were given 25 doses of γ-irradiation totaling 6625 rads, mortality was 14%-15% less 1 week later than when young weevils (1-2 day-old) were similarly treated. However, giving older weevils an acute dose of 6625 rads did not reduce mortality. Seven-day-old weevils receiving the acute treatment mated 10% more than weevils that were 3 days old at the time of treatment. Seven-day-old male weevils exposed to the fractionated treatment transferred sperm to 12% more females than 7-day-old males exposed to the acute treatment. (Auth.)

Clover, Red (Trifolium pretense)

Science.gov (United States)

Genetic modification of plants by the insertion of transgenes can be a powerful experimental approach to answer basic questions about gene product function. This technology can also be used to make improved crop varieties for use in the field. To apply this powerful tool to red clover, an important ...

Survival and preference of cotton boll weevil adults for alternative food sources

Directory of Open Access Journals (Sweden)

M. Pimenta

Full Text Available Abstract Plants that have potential as alternative food source (floral nectar, pollen and plant tissues to the boll weevil during the intercropping season were evaluated considering the prevalent conditions of Cerrado in the Central Brazil. Initially, we tested the nutritional adequacy for the survival of the insect of flower resource (pollen and nectar provided by eight plant species (fennel, mexican sunflower, castor bean, okra, hibiscus, sorghum, pigeonpea and sunn hemp. Subsequently, we tested if the resources provided by the selected plants continued to be exploited by the boll weevil in the presence of cotton plant, its main food source average longevity of boll weevil adults was significantly longer when they were fed on hibiscus’ flowers (166.6 ± 74.4 and okra flowers (34.7 ± 28.9 than when they fed on flowers of other six species. Subsequently, the preference of the boll weevil in the use of resources was compared between okra or hibiscus and cotton plants, in dual choice experiments. Boll weevils preferred plants of the three species in the reproductive stages than those in vegetative stages. Although the cotton plant in the reproductive stage was the most preferred plant of all, boll weevils preferred flowering okra and hibiscus than cotton at the vegetative stage.

Captures of Boll Weevils (Coleoptera: Curculionidae) in Relation to Trap Orientation and Distance From Brush Lines.

Science.gov (United States)

Spurgeon, Dale W

2016-04-01

Eradication programs for the boll weevil (Anthonomus grandis grandis Boheman) rely on pheromone-baited traps to trigger insecticide treatments and monitor program progress. A key objective of monitoring in these programs is the timely detection of incipient weevil populations to limit or prevent re-infestation. Therefore, improvements in the effectiveness of trapping would enhance efforts to achieve and maintain eradication. Association of pheromone traps with woodlots and other prominent vegetation are reported to increase captures of weevils, but the spatial scale over which this effect occurs is unknown. The influences of trap distance (0, 10, and 20 m) and orientation (leeward or windward) to brush lines on boll weevil captures were examined during three noncropping seasons (October to February) in the Rio Grande Valley of Texas. Differences in numbers of captured weevils and in the probability of capture between traps at 10 or 20 m from brush, although often statistically significant, were generally small and variable. Variations in boll weevil population levels, wind directions, and wind speeds apparently contributed to this variability. In contrast, traps closely associated with brush (0 m) generally captured larger numbers of weevils, and offered a higher probability of weevil capture compared with traps away from brush. These increases in the probability of weevil capture were as high as 30%. Such increases in the ability of traps to detect low-level boll weevil populations indicate trap placement with respect to prominent vegetation is an important consideration in maximizing the effectiveness of trap-based monitoring for the boll weevil.

Behavioural response of Heterorhabditis megidis towards plant roots and insect larvae

NARCIS (Netherlands)

Boff, M.I.C.; Tol, van R.W.H.M.; Smits, P.H.

2002-01-01

The behavioural response of infective juveniles (IJs) of Heterorhabditis megidis (strain NLH-E87.3) to cues from roots of strawberry (Fragaria x ananassa Duch.), thuja (Thuja occidentalis L.) and to larvae of the black vine weevil, Otiorhynchus sulcatus, was studied. Choice assays were conducted in

Estimating grass-clover ratio variations caused by traffic intensities using image analysis

DEFF Research Database (Denmark)

Jørgensen, Rasmus Nyholm; Sørensen, Claus Grøn; Green, Ole

Grass and especially clover have a negative yield response as a function of  traffic intensity.  Conventional grass-clover production for silage have high traffic intensity due to fertilizing with slurry, cutting the grass, rolling the grass into swaths, and collecting and chopping the grass...... to fulfill the aim [1]http://www.ruralni.gov.uk/index/publications/press_articles/dairy-2/role-of-clover.htm...

In situ carbon and nitrogen dynamics in ryegrass-clover mixtures

DEFF Research Database (Denmark)

Rasmussen, J.; Eriksen, J.; Jensen, Erik Steen

2007-01-01

=9). 15N-enriched compounds were not detected in percolating pore water, which may be caused by either dilution from irrigation or low availability of leachable N compounds. 14C was found solely as 14CO2 in the pore water indicating that dissolved organic carbon (DOC) did not originate from fresh......Carbon (C) and nitrogen (N) dynamics in a third production year ryegrass–clover mixture were investigated in the field. Cylinders (diameter 29.7 cm) were installed to depths of 20, 40 and 60 cm and equipped with suction cups to collect percolating pore water. Ryegrass and clover leaves were cross......-labelled with 14C- and 15N-enriched urea and the fate of the two tracers was studied for 3 months during summer. Transfer of 14C occurred mainly from ryegrass to clover, whereas the largest transfer of 15N was in the opposite direction. The average transfer of N from clover was 40% (SE±3.1, n=9) of N in ryegrass...

Use of sterile male technique for insects to eradicate red palm weevil

International Nuclear Information System (INIS)

Al-Turaihi, E.H.

2012-01-01

The date palm plantations in the Middle East countries are infested by a devastating insect which is called red palm weevil originally from India and spread firstly into the Arab Gulf countries through imported palm trees. Red palm weevil is mainly controlled by using synthetic chemical pesticides and aggregative pheromone traps. Use of chemical pesticides has dramatically increased during recent years and posed many poisoning cases, pollution of environment, killed beneficial and non-target insects. The aim of this study is to highlight the application of Sterile Insect Technique to suppress or eradicate red palm weevil. The results revealed that the application of Sterile Insect Technique to control cotton boll weevil (Anthonomus grandis) in USA could be considered as an ideal example to apply the Sterile Insect Technique against red palm weevil because both species have similarities such as : both are exotic pests; have protected larval and pupal stages; have limited hosts; have economic importance; have an aggregative pheromone that attracts males and females; that can be used for detection and survey; and finally both insects are Coleopterans belonging to the same family.

Potential for yield in red clover (Trifolium pratense L. varieties

Directory of Open Access Journals (Sweden)

Vasiljević Sanja

2010-01-01

Full Text Available Red clover (Trifolium pratense L. is botanically a perennial, although it often behaves as a biennial. The crop usually lives 2 to 3 seasons in most clover-growing regions of the world and is generally conceded to be lacking in persistence. The objective of this investigation was to analyze the production potential and persistence of domestic and imported red clover varieties. Experiments were conducted at Rimski Šančevi Experiment Field during the period 2004-2006. The experimental materials were six varieties (K-17, Kolubara, Una, Viola, Start, Nike which were analyzed for the most important production characteristics: yield of green mass, dry matter yield and persistence. .

Attraction of milkweed stem weevils, Rhyssomatus spp. (Coleoptera: Curculiondae), to grandlure

Science.gov (United States)

A trapping study was initiated in the spring of 2010 to compare the attraction of boll weevils to standard grandlure (synthesized boll weevil pheromone) and a new experimental formulation of grandlure. Both formulations contained the same four pheromone components, but differed in the proportion of...

Olfactory responses of banana weevil predators to volatiles from banana pseudostem tissue and synthetic pheromone.

Science.gov (United States)

Tinzaara, W; Gold, C S; Dicke, M; van Huis, A

2005-07-01

As a response to attack by herbivores, plants can emit a variety of volatile substances that attract natural enemies of these insect pests. Predators of the banana weevil, Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae) such as Dactylosternum abdominale (Coleoptera: Hydrophilidae) and Pheidole megacephala (Hymenoptera: Formicidae), are normally found in association with weevil-infested rotten pseudostems and harvested stumps. We investigated whether these predators are attracted to such environments in response to volatiles produced by the host plant, by the weevil, or by the weevil plant complex. We evaluated predator responses towards volatiles from banana pseudostem tissue (synomones) and the synthetic banana weevil aggregation pheromone Cosmolure+ in a two-choice olfactometer. The beetle D. abdominale was attracted to fermenting banana pseudostem tissue and Cosmolure+, whereas the ant P. megacephala was attracted only to fermented pseudostem tissue. Both predators were attracted to banana pseudostem tissue that had been damaged by weevil larvae irrespective of weevil presence. Adding pheromone did not enhance predator response to volatiles from pseudostem tissue fed on by weevils. The numbers of both predators recovered with pseudostem traps in the field from banana mats with a pheromone trap were similar to those in pseudostem traps at different distance ranges from the pheromone. Our study shows that the generalist predators D. abdominale and P. megacephala use volatiles from fermented banana pseudostem tissue as the major chemical cue when searching for prey.

Effect of mulching on banana weevil movement relative to pheromone traps

NARCIS (Netherlands)

Tinzaara, W.; Gold, C.S.; Dicke, M.; Huis, van A.; Ragama, P.E.

2008-01-01

Banana weevil (Cosmopolites sordidus) is a major pest in East Africa causing yield losses of up to 14 metric tonnes per hectare annually. A study was conducted in Uganda to determine the effect of mulching on banana (Musa spp. L.) weevil, Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae),

Reproductive dormancy in boll-weevil from populations of the midwest of Brazil.

Science.gov (United States)

Paula, D P; Claudino, D; Timbó, R V; Miranda, J E; Bemquerer, M P; Ribeiro, A C J; Sujii, E R; Fontes, E M G; Pires, C S S

2013-02-01

The boll weevil (Anthonomus grandis Boheman) (Coleoptera: Curculionidae) is an introduced pest in Brazil, which in 30 yr has successfully expanded to various eco-regions and became the most important pest of cotton (Gossypium hirsutum, Malvaceae). Given the limited knowledge about the adaptive mechanisms that allowed successful establishment of the pest population in a tropical region, in this work we studied the potential of the Midwest population of boll weevils to enter a reproductive dormancy and identified the importance of the feeding source for induction of dormancy. We investigated morphological and physiological characters as indicators of the dormancy. We also investigated the occurrence of reproductive dormancy in boll weevils populations from cotton farms of the Midwestern region of Brazil during the cotton and noncotton seasons of 2009 and 2010. The studies revealed that boll weevils entered facultative reproductive dormancy; however, unlike what has been observed for boll weevils from temperate and subtropical regions, the hypertrophy of fat body and hexamerin levels did not straightly correlated to reproductive dormancy. The food source and field conditions during early adult development were decisive factor for the induction of reproductive dormancy. The incidence of reproductive dormancy increased progressively as the phenology of cotton plant advanced, reaching approximately 90% at the end of the crop season. During the noncotton season, the boll weevil was predominantly found in reproductive dormancy, especially females; however, there is evidence of use of multiple adaptive strategies to colonize the next harvest.

Leaching of cyanogenic glucosides and cyanide from white clover green manure

DEFF Research Database (Denmark)

Bjarnholt, Nanna; Lægdsmand, Mette; Hansen, Hans Chr. Bruun

2008-01-01

Use of crops for green manure as a substitute for chemical fertilizers and pesticides is an important approach towards more sustainable agricultural practices. Green manure from white clover is rich in nitrogen but white clover also produces the cyanogenic glucosides (CGs) linamarin...... and lotaustralin; CGs release toxic hydrogen cyanide (HCN) upon hydrolysis which may be utilized for pest control. We demonstrate that applying CGs in the form of a liquid extract of white clover to large columns of intact agricultural soils can result in leaching of toxic cyanide species to a depth of at least 1...

Stable isotope tracer marking of individual boll weevils

International Nuclear Information System (INIS)

James, W.D.; Showler, A.T.; Armstrong, J.S.; Westbrook, J.K.

2006-01-01

Stable isotope markers have been used to study animal nutrition for several decades and more recently to study the foraging and cultural habits of imported fire ants. In this work, we have extended that effort to evaluate the potential for marking boll weevils, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), with the rare earth element samarium to aid in studies of insect invasion and pest eradication protocols. Neutron activation analysis (NAA) was performed on the marked boll weevils as well as plant material from the cotton squares on which the insects were fed. Samarium levels in non-dosed insects average about 20 ng/g or about 100 pg total element per insect. Our computed average determination limit was 36 pg samarium/weevil. The determination limit for cotton plant squares and leaves averaged 3.5 ng/g and 8.2 ng/g, respectively. These initial results indicate the NAA method is capable of identifying individual marked insects which have assimilated 1 ng of samarium, a ten-fold increase in content over average blank values. (author)

Enhancing banana weevil ( Cosmopolites sordidus ) resistance by ...

African Journals Online (AJOL)

Enhancing banana weevil (Cosmopolites sordidus) resistance by plant genetic modification: A perspective. Andrew Kiggundu, Michael Pillay, Altus Viljoen, Clifford Gold, Wilberforce Tushemereirwe, Karl Kunert ...

Estimating the content of clover and grass in the sward using a consumer camera and image processing

DEFF Research Database (Denmark)

Mortensen, Anders Krogh; Karstoft, Henrik; Søegaard, Karen

the dry matter ratio of clover and grass in clover grass fields from sparse close up images. First, the light conditions is determined, which is used for selecting model parameters to estimate the coverage of both clover and grass. Next, the clover and grass coverage are transformed to give the dry matter...

Captures of Boll Weevils (Coleoptera: Curculionidae) in Relation to Trap Distance From Cotton Fields.

Science.gov (United States)

Spurgeon, Dale W

2016-12-01

The boll weevil (Anthonomus grandis grandis Boheman) has been eradicated from much of the United States, but remains an important pest of cotton (Gossypium spp.) in other parts of the Americas. Where the weevil occurs, the pheromone trap is a key tool for population monitoring or detection. Traditional monitoring programs have placed traps in or near the outermost cotton rows where damage by farm equipment can cause loss of trapping data. Recently, some programs have adopted a trap placement adjacent to but outside monitored fields. The effects of these changes have not been previously reported. Captures of early-season boll weevils by traps near (≤1 m) or far (7-10 m) from the outermost cotton row were evaluated. In 2005, during renewed efforts to eradicate the boll weevil from the Lower Rio Grande Valley of Texas, far traps consistently captured more weevils than traps near cotton. Traps at both placements indicated similar patterns of early-season weevil captures, which were consistent with those previously reported. In 2006, no distinction between trap placements was detected. Early-season patterns of captures in 2006 were again similar for both trap placements, but captures were much lower and less regular compared with those observed in 2005. These results suggest magnitude and likelihood of weevil capture in traps placed away from cotton are at least as high as for traps adjacent to cotton. Therefore, relocation of traps away from the outer rows of cotton should not negatively impact ability to monitor or detect the boll weevil. Published by Oxford University Press on behalf of Entomological Society of America 2016. This work is written by a US Government employee and is in the public domain in the US.

Some factors affecting reproduction in the Rice weevil Sitophilus Oryzae (L.)

International Nuclear Information System (INIS)

Hasaballa, Z.A.; Abdelkawy, F.K.

1992-01-01

Laboratory investigations on the effects or radiation, type of food and population density on the reproductive potential of the rice weevil. Sitophilus Oryzae were conducted at 30 degree C. and 75% R.H. The results indicate that the survival number of adult weevils infesting wheat grains increased markedly after 45 and 90 days of infestation. The survival and reproductive potential of the rice weevils declined significantly after exposure to gamma rays. This decline was more pronounced after 90 days and appeared to be markedly dose dependent. It was noticed that the rate of reproduction of the rice weevils was greatly influenced by insect crowding, science adults of S. Oryzae reared under crowded conditions failed to increase in numbers for 3 months as was expected. The reproduction of S. Oryzae was affected by the type of food. Wheat grains were more suitable than rice and maize grains as the average survival numbers of S. Oryzae reared on wheat grains were more after 45 and 90 days than those reared on rice and maize grains.3 tab

Value loss from weevil-caused defects in eastern white pine lumber

Science.gov (United States)

Myron D. Ostrander; Carl H. Stoltenberg

1957-01-01

Owners of eastern white pine stands suffer financially in several ways from attacks by the white-pine weevil (Pissodes strobi). Crooks, forks, and other weevil-caused tree-bole deformities increase bucking, logging, and sawing costs, and they reduce recoverable volumes. The injuries also reduce the average value of the lumber recovered. It is only with this reduction...

Cumulative effects of white clover residues on the changes in soil ...

African Journals Online (AJOL)

White clover grows naturally all over the Himalayan regions including the hilly areas of the state of Azad Jammu and Kashmir (AJK), Pakistan. This study was conducted to investigate the effects of white clover residues alone or in combination with phosphorus (P) fertilizer on maize (Zea mays L.) yield, nutrient uptake and ...

Effect of age, female mating status and density on the banana weevil ...

African Journals Online (AJOL)

The banana (Musa spp.) weevil (Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae) is a major pest in East Africa causing yield losses of up to 14 metric tonnes per hectare annually. Laboratory and field experiments were conducted to determine whether the response of the banana weevil, Cosmopolites sordidus ...

Linyphiid spider populations in sustainable wheat‐clover bi‐cropping compared to conventional wheat‐growing practice

DEFF Research Database (Denmark)

Gravesen, Eigil Vestergaard

2008-01-01

Linyphiid web densities in wheat-clover bi-crop systems where winter wheat was grown in an under-storey of white clover were compared with web densities estimated in conventional wheat-growing systems. The web densities in the wheat-clover bi-crop systems were on average between 200 and 250 webs ...

Effect of microgravity on stress ethylene and carbon dioxide production in sweet clover (Melilotus alba L.)

Science.gov (United States)

Gallegos, Gregory L.; Odom, William R.; Guikema, James A.

1995-01-01

The study of higher plant growth and development in the microgravity (micro-g) environment continues to be a challenge. This is in part a result of the available flight qualified hardware with restrictive closed gas environments. This point is underscored by considering that gas exchange of seedlings grown in microgravity may be further limited owing to a thicker layer of water wicked onto the roots and to the absence of convective mixing. We hypothesized that seedlings grown under such conditions will experience greater hypoxia in microgravity than at Earth gravity, and thus produce greater stress ethylene. We compared flight and ground samples of sweet clover seedlings grown in the Fluid Processing Apparatus (FPA) during STS-57 and found them to contain extremely high levels of carbon dioxide (CO2) and stress ethylene. There were time dependent increases for both gases, and seedling growth was greatly inhibited. We repeated these experiments aboard STS-60 using modified chambers which increased, by fifty fold, the air available to the developing seedlings. Sweet clover seed germination and subsequent seedling growth to eight days within the FPA modified with a gas permeable membrane is not compromised by the microgravity environment.

Evidence for volatile male-produced pheromone in banana weevilCosmopolites sordidus.

Science.gov (United States)

Budenberg, W J; Ndiege, I O; Karago, F W

1993-09-01

Females of the banana weevil,Cosmopolites sordidus, were attracted to and made longer visits to live conspecific males, trapped volatiles from males, and dissected male hindguts in a still-air olfactometer. Male weevils were attracted to volatiles trapped from males and made longer visits to live males and volatiles from males. Live females, collected volatiles from females and female hindguts, elicited small or no behavioral responses from either sex. Electroantennogram (EAG) responses from both male and female antennae were elicited by collected volatiles from males and by dichloromethane extracts of male hindguts and bodies but not by surface washes of males. No significant EAG responses were given to equivalent material from females. It is therefore suggested that male banana weevils release an aggregation pheromone via their hindgut.

Evaluation of extended-life pheromone formulations used with and without dichlorvos for boll weevil (Coleoptera: Curculionidae) trapping.

Science.gov (United States)

Armstrong, J Scott; Greenberg, Shoil M

2008-04-01

Boll weevil traps baited with a ComboLure (25 of mg grandlure + 30 mg of eugenol + 90 of mg dichlorvos [DDVP]), an extended-release lure (25 mg of grandlure + 30 mg of eugenol + 60 of mg DDVP kill-strip), and extended-release lure with no DDVP were evaluated for boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), captures in South Texas cotton, Gossypium hirsutum L., fields during February-March 2005 and March-April 2006. The traps were serviced once a week for five consecutive weeks by using the same methodology as active boll weevil eradication programs. Mean captured boll weevils from extended-release lures with no DDVP were significantly higher in five of 10 trapping weeks compared with captures of the ComboLure and extended lure. Weekly mortality of boll weevils captured was similar for the ComboLure (72.6 +/- 4.7%) and extended lure + DDVP (73.5 +/- 4.0%), and both were significantly higher than the extended lure (32.8 +/- 5.0%) with no DDVP. The presence or absence of DDVP did not significantly affect the sex ratio of field-captured boll weevils. We found no functional reasoning for using DDVP in large scale trapping of boll weevils regardless of the formulation or presentation in the trap. We conducted two additional trapping evaluations after the 2005 and 2006 studies, but the numbers of boll weevils captured were too low for statistical comparisons, indicating that boll weevil eradication is reducing populations in the Rio Grande Valley of Texas.

Screening of promising maize genotypes against maize weevil (Sitophilus zeamais Motschulky in storage condition

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Ram B Paneru

2017-12-01

Full Text Available The maize weevil (Sitophilus zeamais Motschulsky is a serious pest of economic importance in stored grains. It causes major damage to stored maize grain thereby reducing its weight, quality and germination. An experiment was conducted in randomized complete block design (RCBD with 3 replications to screen 32 maize genotypes against maize weevil in no-choice and free-choice conditions at Entomology Division, Khumaltar, Lalitpur (Room temperature: Maximum 24-32°C and Minimum 18-27°C. The findings showed that the maize genotypes had different response to maize weevil damage ranging from susceptible to tolerance. The genotypes Manakamana-3, Lumle White POP Corn and Ganesh-2 showed their tolerance to S. zeamais as evidenced by lower number of weevil emerged/attracted, lower amount of grain debris release and lower proportion of bored grains, while the genotype ZM-627 was the most susceptible to weevil damage in both tests. The other remaining genotypes were intermediate types. This information is useful to improve grain protection in storage and varietal improvement/release program.

Estimation of the Botanical Composition of Clover-Grass Leys from RGB Images Using Data Simulation and Fully Convolutional Neural Networks

Science.gov (United States)

Steen, Kim Arild; Green, Ole; Karstoft, Henrik

2017-01-01

Optimal fertilization of clover-grass fields relies on knowledge of the clover and grass fractions. This study shows how knowledge can be obtained by analyzing images collected in fields automatically. A fully convolutional neural network was trained to create a pixel-wise classification of clover, grass, and weeds in red, green, and blue (RGB) images of clover-grass mixtures. The estimated clover fractions of the dry matter from the images were found to be highly correlated with the real clover fractions of the dry matter, making this a cheap and non-destructive way of monitoring clover-grass fields. The network was trained solely on simulated top-down images of clover-grass fields. This enables the network to distinguish clover, grass, and weed pixels in real images. The use of simulated images for training reduces the manual labor to a few hours, as compared to more than 3000 h when all the real images are annotated for training. The network was tested on images with varied clover/grass ratios and achieved an overall pixel classification accuracy of 83.4%, while estimating the dry matter clover fraction with a standard deviation of 7.8%. PMID:29258215

Reducing boll weevil populations by clipping terminal buds and removing abscised fruiting bodies

Science.gov (United States)

The boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae) punctures cotton squares and young bolls during feeding and oviposition, causing abscission of flower buds (squares) in the instance of oviposition. Fallen squares are a source of next generation adult boll weevils that...

Assessment of nickel bioavailability through chemical extractants and red clover (Trifolium pratense L.) in an amended soil: Related changes in various parameters of red clover.

Science.gov (United States)

Shahbaz, Ali Khan; Iqbal, Muhammad; Jabbar, Abdul; Hussain, Sabir; Ibrahim, Muhammad

2018-03-01

Application of immobilizing agents may efficiently reduce the bioavailability of nickel (Ni) in the soil. Here we report the effect of biochar (BC), gravel sludge (GS) and zeolite (ZE) as a sole treatment and their combinations on the bioavailability of Ni after their application into a Ni-polluted soil. The bioavailability of Ni after the application of immobilizing agents was assessed through an indicator plant (red clover) and chemical indicators of bioavailability like soil water extract (SWE), DTPA and Ca(NO 3 ) 2 extracts. Additionally, the effects of Ni bioavailability and immobilizing agents on the growth, physiological and biochemical attributes of red clover were also observed. Application of ZE significantly reduced Ni concentrations in all chemical extracts compared to rest of the treatments. Similarly, the combined application of BC and ZE (BC+ ZE) significantly reduced Ni concentrations, reactive oxygen species (ROS) whereas, significant enhancement in the growth, physiological and biochemical attributes along with an improvement in antioxidant defence machinery of red clover plant, compared to rest of the treatments, were observed. Furthermore, BC+ ZE treatment significantly reduced bioconcentration factor (BCF) and bioaccumulation factor (BAF) of Ni in red clover, compared to rest of the treatments. The Ni concentrations in red clover leaves individually reflected a good correlation with Ni concentrations in the extracts (SWE at R 2 =0.79, DTPA extract at R 2 =0.84 and Ca(NO 3 ) 2 extracts at R 2 =0.86). Our results indicate that combined application of ZE and BC can significantly reduce the Ni bioavailability in the soil while in parallel improve the antioxidant defence mechanism in plants. Copyright © 2017 Elsevier Inc. All rights reserved.

Temperature influences on diapause induction and survival in the boll weevil (Coleoptera: Curculionidae)

Science.gov (United States)

The boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), has been the most important pest of cotton (Gossypium spp.) wherever it occurs. Although eradication programs in the U.S. have reduced the range of this pest, the weevil remains an intractable problem in subtropical Tex...

Flora and Fauna on Backs of Large Papuan Moss-Forest Weevils.

Science.gov (United States)

Gressitt, J L; Sedlacek, J; Szent-Ivany, J J

1965-12-31

Large, living, flightless weevils feeding on leaves of woody plants high moss forest on various New Guinea mountain ranges have plant growth on their backs. Fungi and algae have been found on 11 species of Gymnopholus, lichens on six species, and liverworts on one species. In other genera of weevils, on the same mountains, there are additional specific associations with fungi, algae, lichens, and liverworts. The fungi and lichens, at least, are inhabited by oribatid mites of a new family, which may spread the plants from beetle to beetle. Also, nematodes, rotifers, psocids, and diatoms occur among the plants. Specialized scales or hairs, and a secretion, in depressions on the weevils' backs, appear to be associated with cpcouragement of the plant growth. Mutualistic symbiotic relationships seem to be clearly indicated.

Modelling interactions in grass-clover mixtures

NARCIS (Netherlands)

Nassiri Mahallati, M.

1998-01-01

The study described in this thesis focuses on a quantitative understanding of the complex interactions in binary mixtures of perennial ryegrass (Lolium perenne L.) and white clover (Trifolium repens L.) under cutting. The first part of the study describes the dynamics of growth, production

Boll weevil: experimental sterilization of large numbers by fractionated irradiation

International Nuclear Information System (INIS)

Haynes, J.W.; Wright, J.E.; Davich, T.B.; Roberson, J.; Griffin, J.G.; Darden, E.

1978-01-01

Boll weevils, Anthonomus grandis grandis Boheman, 9 days after egg implantation in the larval diet were transported from the Boll Weevil Research Laboratory, Mississippi State, MS, to the Comparative Animal Research Laboratory, Oak Ridge, TN, and irradiated with 6.9 krad (test 1) or 7.2 krad (test 2) of 60 Co gamma rays delivered in 25 equal doses over 100 h. In test 1, from 600 individual pairs of T (treated) males x N (normal) females, only 114 eggs hatched from a sample of 950 eggs, and 47 adults emerged from a sample of 1042 eggs. Also, from 600 pairs of T females x N males, 6 eggs hatched of a sample of 6 eggs and 12 adults emerged from a sample of 20 eggs. In test 2, from 700 individual pairs of T males x N females, 54 eggs hatched from a sample of 1510, and 10 adults emerged from a sample of 1703 eggs. Also, in T females x N males matings, 1 egg hatched of a sample of 3, and no adults emerged from a sample of 4. Transportation and handling in the 2nd test reduced adult emergence an avg of 49%. Thus the 2 replicates in test 2 resulted in 3.4 x 10 5 and 4.3 x 10 5 irradiated weevils emerging/day for 7 days. Bacterial contamination of weevils was low

Boll weevil within season and off-season activity monitored using a pheromone-and-glue reusable tube trap

Directory of Open Access Journals (Sweden)

Robério Carlos dos Santos Neves

Full Text Available ABSTRACT: The boll weevil colonizes cotton fields as early as cotton squaring, causing significant losses due to feeding and protected development inside fruiting structures throughout crop phenology. Successful control depends on control of adults and their accurate detection when they colonize the crops. The commercial trap and boll weevil attract-and-control tubes (BWACT are the only available tools to monitor and attract-and-kill boll weevil, despite limitation in efficacy, and insecticide in BWACT is not allowed in organic production. A grandlure-and-glue reusable and insecticide-free tube (GGT made with polyvinyl chloride tube, smeared with entomological glue, and lured with pheromone was tested to detect boll weevil activity across various seasons. Boll weevil showed activity during growing season and off-season from 2009 to 2012 in the Semiarid and with higher numbers captured in GGT in comparisons to commercial traps. GGT was able to detect early weevils in the field right after planting. Further, the overall averages resulted in 34-, 16.8-, and 7.5-times more weevils captured in GGTs compared to the traps during stalk destruction in the Semiarid 2011 and Cerrado season 2012/13 and during the harvesting period in the Cerrado season 2011/12, respectively. Therefore, boll weevils were captured actively during season and off-season and early captures obtained in GGT compared to traps showed a better correlation between captures and square damage.

Parasitoids of boll weevil Anthonomus grandis and resident predators in kaolin-treated cotton

Directory of Open Access Journals (Sweden)

Roberta Leme Santos

2013-12-01

Full Text Available Simultaneous use of control methods is essential to reach success in managing arthropod pests. The current study investigated the effect of kaolin application on resident predators in the cotton plant canopy and parasitism of boll weevil on abscised squares in the field, and parasitism of boll weevil in the laboratory. Predators Araneae, Formicidae, Chrysopidae, and Coccinellidae showed similar seasonal densities for kaolin-treated and untreated cotton fields as well as the emergence rate of the parasitoids Bracon vulgaris Ashmead (Hymenoptera: Braconidae and Catolaccus grandis Burks (Hymenoptera: Pteromalidae from abscised field-collected structures. Under laboratory conditions, the parasitism of boll weevil larvae infesting squares was similar when treated and untreated squares with kaolin were offered to the parasitoid under free choice test. Therefore, the results show that spraying cotton fields with kaolin does not affect the natural biological control by parasitoids of boll weevil and pink bollworm and resident predators naturally occurring in cotton fields.

A radioisotope technique for laboratory studies of the dispersal of rice weevil in grain

International Nuclear Information System (INIS)

Khan, M.Z.A.; Robertson, G.B.

1979-01-01

Adult rice weevils (Sitophilus oryzae (L.)) were marked with paint containing Scandium-46 and detected in a column of wheat 4.5 cm diam by means of a γ-scintillation counter. The radioactive paint had no effect on the mobility and longevity of the insects. Two weevils marked with Sc-46 could be located if they were more than 2.5 cm apart. An account is given of the use of the technique to follow the movements of a single pair of male and female weevils over 8 days. (Auth.)

The influence of silvicultural practices on genetic improvement: height growth and weevil resistance in eastern white pine

Science.gov (United States)

F. Thomas Ledig; D.M. Smith

1981-01-01

When grown in a common environment, the progeny of white pine (Pinus strobus L.) from weeviled stands improved by selection thinning outperformed the progeny of wolfy dominants from untreated stands in both height and weevil resistance. Within families, weevils tended to attack the tallest trees. Among families the relationship was not as strong and...

Investigating the potential of an autodissemination system for managing populations of vine weevil, Otiorhynchus sulcatus (Coleoptera: Curculionidae) with entomopathogenic fungi.

Science.gov (United States)

Pope, Tom W; Hough, Gemma; Arbona, Charlotte; Roberts, Harriet; Bennison, Jude; Buxton, John; Prince, Gill; Chandler, Dave

2018-05-01

Vine weevil, also known as black vine weevil, (Otiorhynchus sulcatus) is an economically important pest affecting soft fruit and nursery stock in temperate regions. We used laboratory and polytunnel experiments to investigate a novel control system based on autodissemination of spores of an entomopathogenic fungus to populations of adult vine weevils. The fungus was applied as a conidial powder, used on its own or formulated with talc, to a simple plastic refuge for vine weevils. The potential for adult weevils to disseminate the fungus was investigated first in polytunnel experiments using fluorescent powders applied to the refuge in lieu of fungal conidia. In this system, 88% of adult weevils came in contact with the powder within 48 h. When the powder was applied to five adult weevils that were then placed within a population of 35 potential recipients, it was transmitted on average to 75% of the recipient population within 7 days. Three isolates of entomopathogenic fungi (Beauveria bassiana isolate codes 433.99 and 1749.11 and Metarhizium brunneum isolate code 275.86), selected from a laboratory virulence screen. These three isolates were then investigated for efficacy when applied as conidial powders in artificial refuges placed among populations of adult weevils held in experimental boxes in the laboratory at 20 °C. Under this regime, the fungal isolates caused 70-90% mortality of adult weevils over 28 days. A final polytunnel experiment tested the efficacy of conidial powders of M. brunneum 275.86 placed in artificial refuges to increase vine weevil mortality. Overall weevil mortality was relatively low (26-41%) but was significantly higher in cages in which the conidial powders were placed in refuge traps than in cages with control traps. The lower weevil mortality recorded in the polytunnel experiment compared to the laboratory test was most likely a consequence of the greater amounts of inoculum required to kill adult weevils when conditions

Efficacy of the organic-certified insecticide Diatect II against the boll weevil (Anthonomus grandis) in cotton.

Science.gov (United States)

Sappington, Thomas W

2002-10-01

The efficacy of the organic insecticide Diatect II against boll weevil (Anthonomus grandis Boheman) in cotton (Gossypium hirsutum L) in the Lower Rio Grande Valley of Texas were assessed in small-plot field trials and greenhouse cage tests using azinphos-methyl treatments as a standard for comparison. Plastic sheets were placed in the furrows of the treated plots to retrieve boll weevils which dropped from the plants after being killed by the insecticides. Samples of live weevils taken by a tractor-mounted vacuum sampler revealed a modest, but significant, reduction in boll weevil populations in Diatect II plots. However, samples of dead weevils indicated that this reduction was due to movement of weevils out of the plots rather than to mortality. This interpretation is supported by greenhouse cage studies, where mortality in Diatect II treated cages was no greater than that in untreated control cages. The effects of insecticide treatments in small plots can be confounded easily and quickly by interplot movement of target insects. Although the relative effects of various compounds can usually be assessed by sampling the populations in plots soon after treatment, the best measure of efficacy is obtained by directly sampling insects that have died in the plot. This parameter is insulated from the effects of interplot movement, unless the toxicant is slow to immobilize the target insect. Taken together, our results indicate little efficacy by Diatect II against boll weevil under our test conditions.

Investigation of pheromone-based factors that may reduce capture of boll weevils in traps

Science.gov (United States)

Boll weevil (Anthonomus grandis Boheman) eradication programs rely almost exclusively on pheromone traps to detect weevils, assess populations, and indicate the need for insecticide treatment. However, instances have been reported recently in Medina Co., TX, where field infestations occur without p...

Rhizobium leguminosarum bv. trifolii rosR is required for interaction with clover, biofilm formation and adaptation to the environment

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Piersiak Tomasz

2010-11-01

Full Text Available Abstract Background Rhizobium leguminosarum bv. trifolii is a symbiotic nitrogen-fixing bacterium that elicits nodules on roots of host plants Trifolium spp. Bacterial surface polysaccharides are crucial for establishment of a successful symbiosis with legumes that form indeterminate-type nodules, such as Trifolium, Pisum, Vicia, and Medicago spp. and aid the bacterium in withstanding osmotic and other environmental stresses. Recently, the R. leguminosarum bv. trifolii RosR regulatory protein which controls exopolysaccharide production has been identified and characterized. Results In this work, we extend our earlier studies to the characterization of rosR mutants which exhibit pleiotropic phenotypes. The mutants produce three times less exopolysaccharide than the wild type, and the low-molecular-weight fraction in that polymer is greatly reduced. Mutation in rosR also results in quantitative alterations in the polysaccharide constituent of lipopolysaccharide. The rosR mutants are more sensitive to surface-active detergents, antibiotics of the beta-lactam group and some osmolytes, indicating changes in the bacterial membranes. In addition, the rosR mutants exhibit significant decrease in motility and form a biofilm on plastic surfaces, which differs significantly in depth, architecture, and bacterial viability from that of the wild type. The most striking effect of rosR mutation is the considerably decreased attachment and colonization of root hairs, indicating that the mutation affects the first stage of the invasion process. Infection threads initiate at a drastically reduced rate and frequently abort before they reach the base of root hairs. Although these mutants form nodules on clover, they are unable to fix nitrogen and are outcompeted by the wild type in mixed inoculations, demonstrating that functional rosR is important for competitive nodulation. Conclusions This report demonstrates the significant role RosR regulatory protein plays in

Forensic pollen geolocation techniques used to identify the origin of boll weevil reinfestation

Science.gov (United States)

The boll weevil, Anthonomus grandis, entered the United States of America in the early 20th century and became a major pest in cotton, Gossypium spp. Shortly after the passage of Tropical Storm Erin on 16 August 2007 through the South Texas/Winter Garden boll weevil eradication zone, over 150 boll ...

A study on the life cycle and the effect of radiation on rice weevil, sitophilus oryzae L.

Energy Technology Data Exchange (ETDEWEB)

1969-12-31

Studies on the life cycle and the effect of radiation on rice weevil, Sitophilus oryzae L. were made. Each stage of development of rice weevil was determined. The egg, larval and pupal stage was 7-9, 13-17 and 7-11 days respectively. The highest rate of oviposition was at 3-6 days. Rice weevils in different stages were exposed to various doses of gamma-radiation and the effects were recorded. It was observed that the males were more susceptible to radiation than females. A dose of 3500-5000 rads induced sterility in adult stage and no hatchability was observed at a dose of 5000 rads. The LD{sub 50} in egg, larval, pupal and adult stage was 15, 120, 1300 and 28400 rads respectively. The response of adult weevils to gamma radiation obtained from Co-60 and the reactor (U{sup 235}) appeared nearly the same. No radioresistance was observed in the second and third generations of rice weevils when adult parents were irradiated at a dose of 2500 rads. There was no recovery of germ cells in male insects following radiation exposure of about 5000 rads. A decrease in the population of rice weevils was noted when the irradiated males were introduced to mate with the non-irradiated females. The Sterile Male Release Technique could be well applied to reduce the number of rice weevils in storage places.

Population density of oil palm pollinator weevil Elaeidobius kamerunicus based on seasonal effect and age of oil palm

Science.gov (United States)

Daud, Syarifah Nadiah Syed Mat; Ghani, Idris Abd.

2016-11-01

The pollinating weevil, Elaedobius kamerunicus (EK) has been known to be the most efficient insect pollinator of oil palm, and has successfully improved the oil palm pollination and increased the yield. Its introduction has greatly reduced the need for assisted pollination. The purpose of this study was to identify the population density of oil palm pollinator weevil EK using the concept of pollinator force and to relate the population density with the seasonal effect and the age of oil palm at Lekir Oil Palm Plantation Batu 14, Perak, Peninsular Malaysia. The pollinator force of the weevil was sustained at a range between 3095.2 to 19126.1 weevils per ha. The overall mean of weevil per spikelet shows that the range of weevil was between 13.51 and 54.06 per spikelet. There was no correlation between rainfall and population density of EK. However, positive correlation was obtained between weevil density and the number of anthesising female inflorescence of oil palm (r= 0.938, poil palm stands had significantly different population density than that of a 8-year old oil palm stand. The information of this study should be useful as a baseline data to investigate why there is such a wide range of weevils per ha or spikelet. Further study should also be done to relate the number pollinator force per spikelete and the Fresh fruit Bunch (FFB), fruit set or fruit to bunch ratio.

Effects of photoperiod on boll weevil (Coleoptera: Curculionidae) development, survival, and reproduction.

Science.gov (United States)

Greenberg, S M; Sappington, T W; Adamczyk, J J; Liu, T-X; Setamou, M

2008-12-01

Effects of photoperiod on development, survival, feeding, and oviposition of boll weevils, Anthonomus grandis grandis Boheman, were assessed under five different photophases (24, 14, 12, 10, and 0 h) at a constant 27 degrees C temperature and 65% RH in the laboratory. Analyses of our results detected positive relationships between photoperiod and puncturing (mean numbers of oviposition and feeding punctures per day), and oviposition (oviposition punctures/oviposition+feeding punctures) activities, and the proportion of squares attacked by boll weevil females. When boll weevil females developed in light:darkness cycles, they produced a significantly higher percentage of eggs developing to adulthood than those developed in 24-h light or dark conditions. In long photoperiod (24:0 and 14:10 h), the number of female progeny was significantly higher and their development time was significantly shorter than those developed in short photoperiod (0:24 and 10:14 h). Lifetime oviposition was significantly highest at 12- and 14-h photophase, lowest at 0- and 10-h photophase, and intermediate at 24 h of light. Life table calculations indicated that boll weevil populations developed in a photoperiod of 14:10 and 12:12 (L:D) h will increase an average of two-fold each generation (Ro) compared with boll weevils developed in 24:0- and 10:14-h photoperiods and 15-fold compared with those at 0:24 h. Knowledge of the photoperiod-dependent population growth potential is critical for understanding population dynamics to better develop sampling protocols and timing insecticide applications.

Efficacy of aggregation pheromone in trapping red palm weevil (Rhynchophorus ferrugineus Olivier) and rhinoceros beetle (Oryctes rhinoceros Linn.) from infested coconut palms.

Science.gov (United States)

Chakravarthy, A K; Chandrashekharaiah, M; Kandakoor, Subhash B; Nagaraj, D N

2014-05-01

Red palm weevil and Rhinoceros beetle are the major pests inflicting severe damage to coconut palms. Due to ineffectiveness of the current management practices to control the two important pests on coconut, a study was conducted to know the attractiveness of red palm weevil and rhinoceros beetle to aggregation pheromone. Olfactometer studies indicated that the aggregation pheromone of red palm weevil and rhinoceros beetle attracted significantly more number of weevils (13.4 females and 7.6 male weevils) and beetles (6.5 male and 12.3 female beetles), respectively than control. Similarly, field studies found that both 750 and 1000 mg pheromone dosage lures of red palm weevil and rhinoceros beetle trapped significantly higher numbers of weevils (695.80 and 789 weevils, respectively) and beetles (98 and 108 beetles, respectively) in traps (P rhinoceros beetle population got trapped. Observations indicated activity of red palm weevil throughout the year and of rhinoceros beetle from September to March around Bangalore, South India. Pheromone traps for red palm weevil can be placed in fields from June to August and October to December and September to February for rhinoceros beetle. Population reductions of the two coleopteran pests by pheromone traps are compatible with mechanical and cultural management tools with cumulative effects.

Tenancy, Marriage, and the Boll Weevil Infestation, 1892-1930.

Science.gov (United States)

Bloome, Deirdre; Feigenbaum, James; Muller, Christopher

2017-06-01

In the early twentieth century, the cotton-growing regions of the U.S. South were dominated by families of tenant farmers. Tenant farming created opportunities and incentives for prospective tenants to marry at young ages. These opportunities and incentives especially affected African Americans, who had few alternatives to working as tenants. Using complete-count Census of Population data from 1900-1930 and Census of Agriculture data from 1889-1929, we find that increases in tenancy over time increased the prevalence of marriage among young African Americans. We then study how marriage was affected by one of the most notorious disruptions to southern agriculture at the turn of the century: the boll weevil infestation of 1892-1922. Using historical Department of Agriculture maps, we show that the boll weevil's arrival reduced the share of farms worked by tenants as well as the share of African Americans who married at young ages. When the boll weevil infestation altered African Americans' opportunities and incentives to marry, the share of African Americans who married young fell accordingly. Our results provide new evidence about the effect of economic and political institutions on demographic transformations.

A Robust Recognition System for Pecan Weevil using Artificial Neural Networks

OpenAIRE

Saleh Mufleh Al-Saqer

2012-01-01

Problem statement: Pecan Weevil is a widely found pest among pecan trees and these pests are known to cause significant damage to the pecan trees resulting in enormous annual losses to pecan growers. Traditional identification techniques for pecan weevil include traps with pheromones to detect the infestation of these pests. However, these traditional methods require expensive labor hours to set-up the traps and their monitoring. These techniques are also unreliable for early detection of pec...

Ecology and phenology of the boll weevil (Coleoptera: Curculionidae) on an unusual wild host, Hibiscus pernambucensis, in southeastern Mexico.

Science.gov (United States)

Arzaluz, I O; Jones, R W

2001-12-01

The phenology and ecology of Hibiscus pernambucensis Arruda and its interaction and importance in maintaining populations of the boll weevil, Anthonomus grandis Boheman, were studied over a period of 3 yr in the Soconusco Region of the state of Chiapas, Mexico. H. pernambucensis is a small tree of Neotropical distribution, restricted to lowland areas, and generally associated with halophytic vegetation. This species is found exclusively along the shores of brackish estuaries, in or near mangrove swamps in southeastern Mexico. In this region, H. pernambucensis has a highly seasonal flowering pattern in which the greatest bud production occurs shortly after the start of the rainy season in May and the highest fruit production occurs in July and August. Boll weevil larvae were found in buds of H. pernambucensis during all months but February and densities of buds and weevils were highest from May through September. The percentage of buds infested with boll weevil larvae rarely exceeded 30%. Because plant densities and reproductive output of H. pernambucensis is relatively low and, consequently, the number of oviposition and larval development sites for boll weevils is limited, the importance of this plant as a source of boll weevils with potential of attacking commercial cotton is minimal in comparison with the quantity produced in cultivated cotton. However, the plant could be important as a reservoir of boll weevils in areas of boll weevil quarantine and eradication programs. The factors and circumstances that may have led to this apparent recent host shift of the boll weevil in this region are discussed.

Failure of pheromone traps in detecting incipient populations of boll weevils (Coleoptera: Curculionidae): Investigation of two potential contributing factors

Science.gov (United States)

Progress towards complete eradication of the boll weevil has been delayed in some areas of Texas due to the inconsistent performance of pheromone traps in detecting incipient weevil populations. In 2008 substantial infestations of boll weevils, Anthonomus grandis Boheman, were detected in several c...

Phenotypic evidence suggests a possible major-gene element to weevil resistance in Sitka spruce

Science.gov (United States)

John N. King; René I. Alfaro; Peter Ott; Lara vanAkker

2012-01-01

The weevil resistance breeding program against the white pine weevil, Pissodes strobi Peck (Coleoptera: Curculionidae), particularly for Sitka spruce (Picea sitchensis (Bong.) Carr), is arguably one of the most successful pest resistance breeding programs for plantation forest species, and it has done a lot to rehabilitate...

Transformation kinetics of corn and clover residues in mineral substrates of different composition

Science.gov (United States)

Pinskii, D. L.; Maltseva, A. N.; Zolotareva, B. N.; Dmitrieva, E. D.

2017-06-01

Mineralization kinetics of corn and clover residues in quartz sand, loam, sand + 15% bentonite, and sand + 30% kaolinite have been studied. A scheme has been proposed for the transformation of plant residues in mineral substrates. Kinetic parameters of mineralization have been calculated with the use of a first-order two-term exponential polynomial. It has been shown that the share of labile organic carbon pool in the clover biomass is higher (57-63%) than in the corn biomass (47-49%), which is related to the biochemical composition of plant residues. The mineralization constants of clover residues generally significantly exceed those of corn because of the stronger stabilization of the decomposition products of corn residues. The turnover time of the labile clover pool (4-9 days) in all substrates and that of the labile corn pool (8-10 days) in sands and substrates containing kaolinites and bentonite are typical for organic acids, amino acids, and simple sugars. In the loamy substrate, the turnover time of labile corn pool is about 46 days due to the stronger stabilization of components of the labile pool containing large amounts of organic acids. The turnover time of the stable clover pool (0.95 years) is significantly lower than that of the stable corn pool (1.60 years) and largely corresponds to the turnover time of plant biomass.

A New NPGS Special Collection: Norman L. Taylor University of Kentucky Clover Collection

Science.gov (United States)

Dr. Norman L. Taylor was a world renowned Professor and clover breeder in the Department of Plant and Soil Sciences at the University of Kentucky for 48 years. Following retirement in 2001, he continued working on clovers up until his death in 2010. Dr. Taylor’s entire career was devoted to enhancin...

The Clover detector

Energy Technology Data Exchange (ETDEWEB)

Beck, F A; Byrski, Th; Durien, D; Duchene, G; France, G de; Kharraja, B; Wei, L [Strasbourg-1 Univ., 67 (France). Centre de Recherches Nucleaires; Butler, P; Jones, G; Jones, P [Liverpool Univ. (United Kingdom). Oliver Lodge Lab.; Hannachi, F [Daresbury Lab. (United Kingdom)

1992-08-01

The EUROGAM Phase I device is almost running for experiments and new technical developments are in progress for its second phase. For example, a composite Ge detector should enable: a very large photopeak efficiency with good energy and timing resolutions; and, the covering, with Ge, of a large portion of 4{pi}-Str. The Clover detector, proposed by the CRN, Strasbourg, is one of this new generation of Ge detectors. It is currently developed in France by the EUROGAM collaboration. The design, the technical characteristics of the counter and the first results of the prototype tests are discussed in this contribution. (author). 1 ref., 2 tabs., 2 refs.

Inclusion of caraway in the ryegrass-red clover mixture modifies soil microbial community composition

DEFF Research Database (Denmark)

Cong, Wenfeng; Jing, Jingying; Søegaard, Karen

-containing grass-clover mixtures may potentially affect soil microbial community structure, biomass and associated ecosystem functions, but it is yet to be elucidated. We hypothesized that inclusion of plantain in the grass-clover mixture would enhance soil microbial biomas and functions through its high biomass...

Attraction of dispersing boll weevils from surrounding habitats relative to simulated pheromone diffusion from traps

Science.gov (United States)

The ability to detect populations of boll weevils, Anthonomus grandis (Boheman), with pheromone traps has contributed significantly in progress toward eradication of the boll weevil. However, new information is needed to aid in the interpretation of trap captures, such as identification of habitats...

Effects of soybean Kunitz trypsin inhibitor on the cotton boll weevil (Anthonomus grandis).

Science.gov (United States)

Franco, Octávio L; Dias, Simoni C; Magalhães, Claudio P; Monteiro, Ana C S; Bloch, Carlos; Melo, Francislete R; Oliveira-Neto, Osmundo B; Monnerat, Rose G; Grossi-de-Sá, Maria Fátima

2004-01-01

The cotton boll weevil, Anthonomus grandis, is an economically important pest of cotton in tropical and subtropical areas of several countries in the Americas, causing severe losses due to their damage in cotton floral buds. Enzymatic assays using gut extracts from larval and adult boll weevil have demonstrated the presence of digestive serine proteinase-like activities. Furthermore, in vitro assays showed that soybean Kunitz trypsin inhibitor (SKTI) was able to inhibit these enzymes. Previously, in vivo effects of black-eyed pea trypsin chymotrypsin inhibitor (BTCI) have been demonstrated towards the boll weevil pest. Here, when neonate larvae were reared on an artificial diet containing SKTI at three different concentrations, a reduction of larval weight of up to 64% was observed for highest SKTI concentration 500 microM. The presence of SKTI caused an increase in mortality and severe deformities of larvae, pupae and adult insects. This work therefore represents the first observation of a Kunitz trypsin inhibitor active in vivo and in vitro against A. grandis. Bioassays suggested that SKTI could be used as a tool in engineering crop plants, which might exhibit increased resistance against cotton boll weevil.

Components of competitiveness in sterile male boll weevils (Coleoptera: Curculionidae)

International Nuclear Information System (INIS)

Villavaso, E.J.; McGovern, W.L.; Wagner, T.L.; Willers, J.L.

1998-01-01

This study examines the relative importance of age at the time of irradiation on attractiveness, mating ability, sperm transfer, prior mating, and longevity as factors of competitiveness in sterile male boll weevil, Anthonomus grandis grandis Boheman. The amount of sperm transferred by irradiated males appeared to be the most important factor in competitiveness. More sperm was transferred by virgin males irradiated on day 5 than by virgin males irradiated on day 2, and males irradiated on day 5 had greater impact on egg hatch than those irradiated on day 2. The amount of sperm in spermathecae of females mated to virgin mates irradiated on day 5 was indistinguishable from that in females mated to virgin control males. Mating ability of males of all treatments was similar. Comparable numbers of boll weevils were captured in traps baited with males irradiated at 2 or 5 d during the first 4-5 d after irradiation, but thereafter, generally more weevils were captured in traps baited with males irradiated at 2 d or with control males. Attractiveness of males irradiated at 2 d was generally comparable to that of control males. More than 91% of irradiated males individually caged on cotton, Gossypium hirsutum L., plants lived for 10 d in the field, and 40% lived for 14 d; all individually caged control males lived 14 d. When released into cotton fields, however, the numbers of both irradiated and control males declined sharply over 14 d. Thus, the potential for an effective 2-wk life span in the field suggested by the caged study did not appear to apply to laboratory-reared weevils released into cotton fields

The boll weevil plague and its effect on the southern agricultural sector, 1889–1929

DEFF Research Database (Denmark)

Ager, Philipp; Brueckner, Markus; Herz, Benedikt

2017-01-01

In the early 1890s, cotton fields in the American South were ravaged by the boll weevil. Using a model that controls for differences in the intensity of cotton production at the county level, we show how the boll weevil significantly changed southern agricultural labor arrangements and labor market...

Evolution: Weevils Get Tough on Symbiotic Tyrosine.

Science.gov (United States)

Dale, Colin

2017-12-04

Weevils, which represent one of the most diverse groups of terrestrial insects in nature, obtain a tough exoskeleton through the activity of an ancient bacterial symbiont with a tiny genome that serves as a factory for the production of tyrosine. Copyright © 2017 Elsevier Ltd. All rights reserved.

Genetics of resistance to stored grain weevil (Sitophilus oryzae L. in maize

Directory of Open Access Journals (Sweden)

Rajkumar Zunjare

2015-12-01

Full Text Available Stored grain weevil (Sitophilus oryzae has emerged as important storage grain pest of maize, causing substantial economic losses. Owing to high costs and environmental hazards of pesticides, host plant resistance holds promise for effective control of weevils. In the present study, a set of experimental maize hybrids generated using line × tester mating design were evaluated against S. oryzae. Significant variation for grain weight loss (GWL (6.0–49.1%, number of insect progeny emerged (NIP (17.8–203.3, grain hardness (GH (263.1–495.4 N, and pericarp thickness (PT (60.3–161.0 μm was observed. Strong positive association was observed between GWL and NIP. GH and PT did not show any correlation with GWL and NIP. Additive and non-additive gene actions were important for both GWL and NIP. Promising inbreds and experimental crosses identified can be effectively utilized in the resistance breeding programme. In majority of promising crosses having desirable SCA effects, one of the parents had desirable GCA effects, indicating that selection of inbred parents based on per se performance for generating resistant crosses may be possible. The commercial hybrid checks were highly susceptible compared to experimental hybrids. The inbreds and experimental hybrids identified hold promise in developing weevil resistant maize cultivars offering sustainable solution to management of weevils in maize.

Mechanical damage in cotton buds caused by the boll weevil

Directory of Open Access Journals (Sweden)

Santos Roseane Cavalcanti

2003-01-01

Full Text Available The boll weevil (Anthonomus grandis Boheman causes high levels of bud abscission in cotton plants due to feeding or oviposition punctures. It has been reported that abscission is mainly due to enzymes present in the insect's saliva, but mechanical damage could also contribute to square abscission. The objective of this paper was to undertake an analysis of the morphological damages caused by the insect in cotton squares using microscopy. Anthers and ovules are the main target of boll weevil feeding. The process initiates by perforation of young sepal and petal tissues and proceeds with subsequent alimentation on stamen and ovary leading to abscission of floral structures.

Genotypic variation for maize weevil resistance in eastern and ...

African Journals Online (AJOL)

ACSS

Uganda Journal of Agricultural Sciences by National Agricultural Research Organisation ... damage, median development period, Dobie's index of susceptibility, and ... resistance and grain yield, suggesting that breeding for maize weevil ...

Feeding and oviposition deterrent activities of flower buds of globemallow,Sphaeralcea emoryi torrey, against boll weevil,Anthonomus grandis Boheman (Coleoptera: Curculionidae).

Science.gov (United States)

Honda, H; Bowers, W S

1996-01-01

The globemallow,Sphaeralcea emoryi Torrey, a plant native to Arizona was evaluated as a source of feeding or oviposition deterrents to the boll weevil,Anthonomus grandis Boheman. Feeding and oviposition responses of reproductive weevils to the flower buds and artificial diets spiked with dry powder or extracts of the globemallow buds were determined. Boll weevils were deterred from feeding and ovipositing in the flower buds unless the calyxes were removed. Male and virgin female weevils were discouraged from feeding as much as gravid weevils. Secondary chemicals in the flower buds served primarily as feeding deterrents but also prevented oviposition. The concentration of these chemicals was highest in the calyxes of the buds, and potent deterrent activity could be extracted from the calyxes with methanol. Boll weevils were able to perceive the deterrents by contact chemosensory organs on the antennae, maxillary palps and labial palps.

Effect of fertilizer type on cadmium and fluorine concentrations in clover herbage

International Nuclear Information System (INIS)

McLaughlin, M.J.

2002-01-01

This study investigated whether changing phosphatic fertilizer type affects the accumulation of cadmium (Cd) and fluorine (F) in pasture herbage. North Carolina phosphate rock and partially acidulated fertilizers derived from this rock generally have higher Cd and F concentrations compared to single superphosphate currently manufactured in Australia. Clover herbage from sites of the National Reactive Phosphate Rock (RPR) trial was collected and analysed for concentrations of Cd (11 sites) and F (4 sites). A comparison was made between pastures fertilized with 4 rates of single superphosphate, North Carolina phosphate rock, and partially acidulated phosphate rock having Cd concentrations of 283, 481, and 420 mg Cd/kg P respectively, and 170, 271, and 274 g F/kg P respectively. One site used Hemrawein (Egypt) phosphate rock (HRP) having a Cd and F concentration of 78 mg Cd/kg P and 256 g F/kg P respectively. To help identify differences in herbage Cd concentrations between sites, unfertilised soils from each site were analyzed for total and extractable Cd contents. At one site Cd concentrations in bulk herbage (clover, grasses and weeds) were related to infestation of the pasture by capeweed (Arctotheca calendula L. Levyns). There were no significant differences between F in herbage from plots fertilized with single superphosphate, partially acidulated phosphate rock or North Carolina phosphate rock, or between sites. Concentrations of F in herbage were low, generally less than 10 mg F /kg. However, there were large differences in Cd concentrations in herbage between sites, while differences between fertilizer treatments were small in comparison. The site differences were only weakly related to total or extractable (0.01 mol/L CaCl 2 ) Cd concentrations in soil. Significant differences in Cd concentrations in clover due to fertilizer type were found at 5 sites. North Carolina phosphate rock treatments had significantly higher Cd concentrations in clover compared to

Effects of clover density on N2O emissions and plant-soil N transfers in a fertilised upland pasture

DEFF Research Database (Denmark)

Klumpp, Katja; Bloor, Juliette M. G.; Ambus, Per

2011-01-01

regression analysis revealed that water-filled pore space (WFPS) and clover dry mass were the main factors driving cumulative N2O emissions in the high clover treatment, whereas variation in cumulated N2O emissions in the low clover treatment was best explained by WFPS and grass mass. We hypothesize...

Rice weevil response to basil oil fumigation

Science.gov (United States)

Basil oil, Ocimum basilicum L., is a volatile plant essential oil that is known to have insecticidal activity against stored product pests such as rice weevil, Sitophilus oryzae (L.). Basil oil was diluted in acetone and applied to a sponge held inside a tea strainer for fumigations in containers wi...

Effect of age, female mating status and density on the banana weevil response to aggregation pheromone

NARCIS (Netherlands)

Tinzaara, W.; Gold, C.S.; Dicke, M.; Huis, van A.; Ragama, P.E.

2011-01-01

The banana (Musa spp.) weevil (Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae) is a major pest in East Africa causing yield losses of up to 14 metric tonnes per hectare annually. Laboratory and field experiments were conducted to determine whether the response of the banana weevil,

Arbuscular mycorrhizal fungi can decrease the uptake of uranium by subterranean clover grown at high levels of uranium in soil

International Nuclear Information System (INIS)

Rufyikiri, Gervais; Huysmans, Lien; Wannijn, Jean; Hees, May van; Leyval, Corinne; Jakobsen, Iver

2004-01-01

Subterranean clover inoculated or not with the arbuscular mycorrhizal (AM) fungus Glomus intraradices was grown on soil containing six levels of 238 U in the range 0-87 mg kg -1 . Increasing U concentration in soil enhanced the U concentration in roots and shoots of both mycorrhizal and nonmycorrhizal plants but had no significant effects on plant dry matter production or root AM colonization. Mycorrhizas increased the shoot dry matter and P concentration in roots and shoots, while in most cases, it decreased the Ca, Mg and K concentrations in plants. The AM fungus influenced U concentration in plants only in the treatment receiving 87 mg U kg -1 soil. In this case, U concentration in shoots of nonmycorrhizal plants was 1.7 times that of shoots of mycorrhizal plants. These results suggested that mycorrhizal fungi can limit U accumulation by plants exposed to high levels of U in soil. - Plant mycorrhization may decrease U concentration in shoots of plants grown at high level of U in soil

Components of male aggregation pheromone of strawberry blossom weevil, Anthonomus rubi herbst. (Coleoptera:Curculionidae).

Science.gov (United States)

Innocenzi, P J; Hall, D R; Cross, J V

2001-06-01

The strawberry blossom weevil, Anthonomus rubi, is a major pest of strawberries in the United Kingdom and continental Europe. As part of a project to develop noninsecticidal control methods, the pheromone system of this species was investigated. Comparison of volatiles produced by field-collected, overwintering individuals of each sex led to identification of three male-specific compounds--(Z)-2-(3,3-dimethylcyclohexylidene)ethanol, (cis)-1-methyl-2-(1-methylethenyl)cyclobutaneethanol, and 2-(1-methylethenyl)-5-methyl-4-hexen-1-ol (lavandulol)--in amounts of 6.1, 1.2, and 0.82 microg/day/ male. The first two compounds are components of the aggregation pheromone of the boll weevil, Anthonomus grandis, grandlure II and grandlure I, respectively. Grandlure I was the (1R,2S)-(+) enantiomer and lavandulol was a single enantiomer, although the absolute configuration was not determined. Trace amounts of the other two grandlure components (Z)-(3,3-dimethylcyclohexylidene)acetaldehyde (grandlure III) and (E)-(3,3-dimethylcyclohexylidene)acetaldehyde (grandlure IV) were also detected. (E,E)-1-(1-Methylethyl)-4-methylene-8-methyl-2,7-cyclo-decadiene (germacrene-D), a known volatile from strawberry plants, Fragaria ananassa, was collected in increased amounts in the presence of pheromone-producing weevils. Male weevils only produced pheromone on F. ananassa and not on scented mayweed, Matracaria recutita, or cow parsley, Anthriscus sylvestris, although these are known food sources. In field trials using various combinations of synthetic grandlures I, II, III, and IV and lavandulol, significantly more weevils were caught in traps baited with blends containing grandlure I and II and lavandulol than in those baited with blends without lavandulol or unbaited controls. Addition of grandlure III and IV had no significant effect on attractiveness. Horizontal sticky traps were found to be more effective than vertical sticky traps or standard boll weevil traps. In mid-season females

Argentine stem weevil ( Listronotus bonariensis, Coleoptera: Curculionidae) population dynamics in Canterbury, New Zealand dryland pasture.

Science.gov (United States)

Goldson, S L; Barron, M C; Kean, J M; van Koten, C

2011-06-01

The Argentine stem weevil (Listronotus bonariensis) was an economically important pest in New Zealand pastures until the release of the parasitoid Microctonus hyperodae. This contribution uses historical data to investigate the regulation of the pest populations prior to, and somewhat during, the establishment of this parasitoid in dryland Canterbury, New Zealand. Thus, a significant goal of this study is to provide an L. bonariensis population dynamics baseline for any future work that aims to analyse the full effects of M. hyperodae on the weevil, now that equilibrium with the weevil host has been reached.The population dynamics of L. bonariensis, based on a life-table approach, were investigated using data collected regularly for eight years from populations in Canterbury, New Zealand. The key factor affecting end-of-season L. bonariensis density was found to be variation in second generation fourth instar prepupal and pupal mortality. This may have been caused by arrested development and ongoing mortality resulting from the onset of cooler autumnal conditions.A compensatory response was found in recruitment to the second summer weevil generation, whereby the realised fecundity of the emergent first summer generation of weevils was found to be negatively related to the density of adult weevils per ryegrass tiller. This is the first time that this has been found via long-term population analysis of L. bonariensis, although indications of this have been found elsewhere in caging, pot and small plot experiments.In this study, the effect of the parasitoid biocontrol agent Microctonus hyperodae on L. bonariensis population dynamics was unclear, as the analysis covered a period when the parasitoid Microctonus hyperodae was introduced and still establishing. It does, however, raise important questions for future analysis in terms of the interaction between parasitism and unrealised fecundity.The results in this contribution also highlighted regional differences

Morphology, diet, and temperature dependent host-free survival of the boll weevil, Anthonomus grandis (Coleoptera: Curculionidae)

Science.gov (United States)

The boll weevil, Anthonomus grandis grandis Boheman, is an important pest of cotton (Gossypium spp.) in South America, Mexico, and southernmost Texas in the United States. A key factor in the persistence of the boll weevil is its ability to survive the non-cotton season. Mechanisms facilitating this...

Control of Cowpea Weevil, Callosobruchus Maculatus (F.) (Coleoptera: Bruchidae), Using Natural Plant Products

OpenAIRE

Tiroesele, Bamphitlhi; Thomas, Kesegofetse; Seketeme, Seipati

2014-01-01

A laboratory study was conducted to investigate the effects of natural products on the reproduction and damage of Callosobruchus maculatus, the cowpea weevil, on cowpea seeds at Botswana College of Agriculture in Gaborone, Botswana. The cowpea variety Blackeye was used in the study. Fifty grams of each plant product (garlic, peppermint and chilies) was added to 500 g of the cowpea seeds. Findings of this experiment revealed that chilies and garlic had negative effects on cowpea weevils for al...

Improving Cry8Ka toxin activity towards the cotton boll weevil (Anthonomus grandis).

Science.gov (United States)

Oliveira, Gustavo R; Silva, Maria C M; Lucena, Wagner A; Nakasu, Erich Y T; Firmino, Alexandre A P; Beneventi, Magda A; Souza, Djair S L; Gomes, José E; de Souza, José D A; Rigden, Daniel J; Ramos, Hudson B; Soccol, Carlos R; Grossi-de-Sa, Maria F

2011-09-09

The cotton boll weevil (Anthonomus grandis) is a serious insect-pest in the Americas, particularly in Brazil. The use of chemical or biological insect control is not effective against the cotton boll weevil because of its endophytic life style. Therefore, the use of biotechnological tools to produce insect-resistant transgenic plants represents an important strategy to reduce the damage to cotton plants caused by the boll weevil. The present study focuses on the identification of novel molecules that show improved toxicity against the cotton boll weevil. In vitro directed molecular evolution through DNA shuffling and phage display screening was applied to enhance the insecticidal activity of variants of the Cry8Ka1 protein of Bacillus thuringiensis. Bioassays carried out with A. grandis larvae revealed that the LC50 of the screened mutant Cry8Ka5 toxin was 3.15-fold higher than the wild-type Cry8Ka1 toxin. Homology modelling of Cry8Ka1 and the Cry8Ka5 mutant suggested that both proteins retained the typical three-domain Cry family structure. The mutated residues were located mostly in loops and appeared unlikely to interfere with molecular stability. The improved toxicity of the Cry8Ka5 mutant obtained in this study will allow the generation of a transgenic cotton event with improved potential to control A. grandis.

Improving Cry8Ka toxin activity towards the cotton boll weevil (Anthonomus grandis

Directory of Open Access Journals (Sweden)

Gomes José E

2011-09-01

Full Text Available Abstract Background The cotton boll weevil (Anthonomus grandis is a serious insect-pest in the Americas, particularly in Brazil. The use of chemical or biological insect control is not effective against the cotton boll weevil because of its endophytic life style. Therefore, the use of biotechnological tools to produce insect-resistant transgenic plants represents an important strategy to reduce the damage to cotton plants caused by the boll weevil. The present study focuses on the identification of novel molecules that show improved toxicity against the cotton boll weevil. In vitro directed molecular evolution through DNA shuffling and phage display screening was applied to enhance the insecticidal activity of variants of the Cry8Ka1 protein of Bacillus thuringiensis. Results Bioassays carried out with A. grandis larvae revealed that the LC50 of the screened mutant Cry8Ka5 toxin was 3.15-fold higher than the wild-type Cry8Ka1 toxin. Homology modelling of Cry8Ka1 and the Cry8Ka5 mutant suggested that both proteins retained the typical three-domain Cry family structure. The mutated residues were located mostly in loops and appeared unlikely to interfere with molecular stability. Conclusions The improved toxicity of the Cry8Ka5 mutant obtained in this study will allow the generation of a transgenic cotton event with improved potential to control A. grandis.

7 CFR 202.44 - Proceedings under section 305(b) to determine whether foreign alfalfa or red clover seed is not...

Science.gov (United States)

2010-01-01

... foreign alfalfa or red clover seed is not adapted for general agricultural use in the United States. 202... Proceedings under section 305(b) to determine whether foreign alfalfa or red clover seed is not adapted for... for the purpose of determining whether seed of alfalfa or red clover from any foreign country or...

Insects in IBL-4 pine weevil traps

Science.gov (United States)

I. Skrzecz

2003-01-01

Pipe traps (IBL-4) are used in Polish coniferous plantations to monitor and control the pine weevil (Hylobius abietis L.). This study was conducted in a one-year old pine plantation established on a reforested clear-cut area in order to evaluate the impact of these traps on non-target insects. Evaluation of the catches indicated that species of

Association of phytoplasmas and viruses with malformed clovers

Czech Academy of Sciences Publication Activity Database

Fránová, Jana; Paltrinieri, S.; Botti, S.; Šimková, Marie; Bertaccini, A.

2004-01-01

Roč. 49, č. 5 (2004), s. 617-624 ISSN 0015-5632 R&D Projects: GA AV ČR IBS5051014 Institutional research plan: CEZ:AV0Z5051902 Keywords : mycoplasma-like organismus * viruses * clovers * classification Subject RIV: EE - Microbiology, Virology Impact factor: 1.034, year: 2004

Evaluation of the Boll Weevil Anthonomus grandis Boheman (Coleoptera: Curculionidae) suppression program in the state of Goiás, Brazil.

Science.gov (United States)

de Lima, I S; Degrande, P E; Miranda, J E; dos Santos, W J

2013-02-01

The boll weevil Anthonomus grandis Boheman (Coleoptera: Curculionidae) is the most important cotton pest in Brazil. A large-scale field-testing of a Boll Weevil Suppression Program (BWSP) was implemented to assess its technical and operational feasibility for boll weevil suppression in the state of Goiás, Brazil. The pilot plan focused on 3,608 ha of cotton during the 2006/2007 and 6,011 ha in the 2007/2008 growing seasons; the areas were divided into four inner zones with an outer buffer zone. We analyzed data on boll weevil captures using pheromone traps installed in the BWSP fields, on the detection of the first insect and the first damaged floral bud, greatest damage, and number of insecticide applications. The nonparametric Mann-Whitney U test was used to evaluate the differences between presuppression and suppression years. Fourteen pheromone-baited trapping evaluations were used to compare the weevil populations from 2006/2007 and 2007/2008 growing seasons. The BWSP regime reduced in-season boll weevil captures from 15- to 500-fold compared to presuppression levels in the preceding year. The low capture rates were related to delays in infestation and damage by weevils. The smaller population size measured by trapping and field monitoring reduced the number of required insecticide treatments. The BWSP strategy was efficient in suppressing populations of this pest and is a viable program for cotton production in subtropical and tropical regions, with long-term economic and environmental benefits.

Nitrogen fertilization of grass/clover swards under cutting or grazing by dairy cows

DEFF Research Database (Denmark)

Søegaard, Karen

2009-01-01

farms over a period of three years. Nitrogen was applied at four rates (0, 75, 150, and 225 kg N year-1) with cutting or grazing regime in Year 1 and Year 2, after establishment. A spring-only application of 150 kg N was compared with four applications during the season, which was the fertilization...... affected. The results indicate different possibilities for strategic fertilization both at farm and field level, and in swards with a high clover content it demonstrates how the clover content can be used as a buffer both for maximizing the N-response and for manipulating the production profile.......Intensively managed perennial ryegrass/white clover (Lolium perenne L. and Trifolium repens L.) swards receive relatively high levels of fertilizer N, and high N surpluses can subsequently be found. The N-fertilization effects on growth, yield, and herbage quality were therefore examined on three...

Karyotypic analysis of the cotton boll weevil, Anthonomus grandis Boheman.

Science.gov (United States)

McNally, L R; Beck, M L; Biggers, C J

2000-01-01

The diploid chromosome number of the cotton boll weevil, Anthonomus grandis Boheman, is 44. Both C- and N-banding techniques of mitotic cells demonstrated constitutive heterochromatin in the p arm of the eight largest chromosomes, the p arm of the X chromosome, and the centromeric region of autosomal groups A-D. Neither the y nor the group E autosomes appeared to contain constitutive heterochromatin. Supernumerary chromosomes were not found in the boll weevil. Restriction endonuclease banding of primary spermatocytes revealed a rod-shaped Xy tetrad in which the X and y were terminally associated. The p arm of the large, submetacentric X was C-band positive. While two of the autosomal tetrads were typically ring-shaped in primary spermatocytes, the remaining 19 autosomal tetrads were rod-shaped.

THE USE OF GRIGNARD REAGENT IN PHEROMONE SYNTHESIS FOR PALM WEEVIL (Rhynchorus, Sp

Directory of Open Access Journals (Sweden)

Warsito Warsito

2010-06-01

Full Text Available In an integrated controlling system of palm weevil, using of synthetic feromoid is strickly needed. The research is aimed to synthesize pheromone which secreted by the weevil, e.g. 4-methyl-5-nonanol (R. ferrugineus and 3-methyl-4-octanol (R. schach through Grignard reagent which formed in situ. The synthesis was proceded by retrosynthesis to determine the precursor, valeraldehyde. The precursor was reacted with Grignard reagent of sec-amyl magnesium bromide (R. ferrugenieus and sec-butyl magnesium bromide (R. shach which made in situ. Characterization of the synthetic molecular pheromone was performed by Gas Chromatography-mass spectroscopy and Fourier Transformed Infra Red. The bioassay of the molecule was carried out by olfactometer. The result showed that the conversion of the reactions were 51.28% (4-methyl-5-nonanol and 85.90% (3-methyl-4-octanol. The character of physico-chemical and bioactivity of the synthetic pheromone are identic with natural pheromones.   Keywords: palm weevil, pheromone, grignard reagent

Proteolytic processing of the vitellogenin precursor in the boll weevil, Anthonomus grandis.

Science.gov (United States)

Heilmann, L J; Trewitt, P M; Kumaran, A K

1993-01-01

The soluble proteins of the eggs of the coleopteran insect Anthonomus grandis Boheman, the cotton boll weevil, consist almost entirely of two vitellin types with M(r)s of 160,000 and 47,000. We sequenced their N-terminal ends and one internal cyanogen bromide fragment of the large vitellin and compared these sequences with the deduced amino acid sequence from the vitellogenin gene. The results suggest that both the boll weevil vitellin proteins are products of the proteolytic cleavage of a single precursor protein. The smaller 47,000 M(r) vitellin protein is derived from the N-terminal portion of the precursor adjacent to an 18 amino acid signal peptide. The cleavage site between the large and small vitellins at amino acid 362 is adjacent to a pentapeptide sequence containing two pairs of arginine residues. Comparison of the boll weevil sequences with limited known sequences from the single 180,000 M(r) honey bee protein show that the honey bee vitellin N-terminal exhibits sequence homology to the N-terminal of the 47,000 M(r) boll weevil vitellin. Treatment of the vitellins with an N-glycosidase results in a decrease in molecular weight of both proteins, from 47,000 to 39,000 and from 160,000 to 145,000, indicating that about 10-15% of the molecular weight of each vitellin consists of N-linked carbohydrate. The molecular weight of the deglycosylated large vitellin is smaller than that predicted from the gene sequence, indicating possible further proteolytic processing at the C-terminal of that protein.

Cultural control of banana weevils in Ntungamo, southwestern Uganda

NARCIS (Netherlands)

Okech, S.H.; Gold, C.S.; Bagamba, F.; Masanza, M.; Tushemereirwe, W.; Ssennyonga, J.

2005-01-01

The International Institute of Tropical Agriculture and the Uganda National Banana Research Programme tested and evaluated selected cultural management options for the banana weevil through on-farm farmer participatory research in Ntungamo district, Uganda between 1996 and 003. A farmer adoption

(Allium sativum L.) Liliaceae as protectants against the maize weevil ...

African Journals Online (AJOL)

REV. FR. ANTHONY

2014-03-05

, was evaluated as a possible grain protectant against the maize weevil, Sitophilus zeamais (Motsch.). Each experiment was set out in completely randomized design (CRD) with four replications and a control treatment. Adult.

Transcriptome analysis of Gossypium hirsutum flower buds infested by cotton boll weevil (Anthonomus grandis) larvae.

Science.gov (United States)

Artico, Sinara; Ribeiro-Alves, Marcelo; Oliveira-Neto, Osmundo Brilhante; de Macedo, Leonardo Lima Pepino; Silveira, Sylvia; Grossi-de-Sa, Maria Fátima; Martinelli, Adriana Pinheiro; Alves-Ferreira, Marcio

2014-10-04

Cotton is a major fibre crop grown worldwide that suffers extensive damage from chewing insects, including the cotton boll weevil larvae (Anthonomus grandis). Transcriptome analysis was performed to understand the molecular interactions between Gossypium hirsutum L. and cotton boll weevil larvae. The Illumina HiSeq 2000 platform was used to sequence the transcriptome of cotton flower buds infested with boll weevil larvae. The analysis generated a total of 327,489,418 sequence reads that were aligned to the G. hirsutum reference transcriptome. The total number of expressed genes was over 21,697 per sample with an average length of 1,063 bp. The DEGseq analysis identified 443 differentially expressed genes (DEG) in cotton flower buds infected with boll weevil larvae. Among them, 402 (90.7%) were up-regulated, 41 (9.3%) were down-regulated and 432 (97.5%) were identified as orthologues of A. thaliana genes using Blastx. Mapman analysis of DEG indicated that many genes were involved in the biotic stress response spanning a range of functions, from a gene encoding a receptor-like kinase to genes involved in triggering defensive responses such as MAPK, transcription factors (WRKY and ERF) and signalling by ethylene (ET) and jasmonic acid (JA) hormones. Furthermore, the spatial expression pattern of 32 of the genes responsive to boll weevil larvae feeding was determined by "in situ" qPCR analysis from RNA isolated from two flower structures, the stamen and the carpel, by laser microdissection (LMD). A large number of cotton transcripts were significantly altered upon infestation by larvae. Among the changes in gene expression, we highlighted the transcription of receptors/sensors that recognise chitin or insect oral secretions; the altered regulation of transcripts encoding enzymes related to kinase cascades, transcription factors, Ca2+ influxes, and reactive oxygen species; and the modulation of transcripts encoding enzymes from phytohormone signalling pathways. These

PERSISTENCE ASSESSMENT OF RED CLOVER (Trifolium pratense L. IN TÂRGOVISTE PLAIN

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D. DUNEA

2008-05-01

Full Text Available Since the most important deficiency of forage stands is the inability to maintain adequate legume participation in mixture, it is the purpose of this paper to examine persistence in red clover in Târgoviste Plain eco-climatic conditions, together with the factors that affect it. Six red clover cultivars (Napoca-Tetra, Dacia Tetra, Vesna – tetraploids; Flora, Roxana, Start – diploids and one white clover diploid cultivar (Karina were used in pure culture and in mixture (50:50 with hybrid ryegrass (Zefir – tetraploid in a randomized block design with three replicates. Ground cover assessment in early spring was a suggestive indicator of the stand persistence to define the stability and sustainability boundaries of a reliable intensive system. In the beginning of the third year of cropping, ground cover was 54.33% for tetraploid cultivars (CV = 43.25%, and 67% for diploid cultivars (CV = 6.83% in pure stands. Same ground cover average of 27% was established both for tetraploid cultivars (CV = 36.47%, and for diploid cultivars (CV = 16.97% in mixtures with hybrid ryegrass.

A screening method for banana weevil ( Cosmopolites sordidus ...

African Journals Online (AJOL)

The banana weevil (Cosmopolites sordidus Germar) is a serious pest in most banana-growing areas of the world. Host-plant resistance is considered to be the most feasible and sustainable method for its control. However, a quick and effective method for screening banana genotypes for resistance against the banana ...

Screening of promising maize genotypes against maize weevil (Sitophilus zeamais Motschulky) in storage condition

OpenAIRE

Ram B Paneru; Resham B Thapa

2017-01-01

The maize weevil (Sitophilus zeamais Motschulsky) is a serious pest of economic importance in stored grains. It causes major damage to stored maize grain thereby reducing its weight, quality and germination. An experiment was conducted in randomized complete block design (RCBD) with 3 replications to screen 32 maize genotypes against maize weevil in no-choice and free-choice conditions at Entomology Division, Khumaltar, Lalitpur (Room temperature: Maximum 24-32°C and Minimum 18-27°C). The fin...

Genetic profiling to determine potential origins of boll weevils (Coleoptera: Curculionidae) captured in a Texas eradication zone: endemicity, immigration, or sabotage?

Science.gov (United States)

Kim, Kyung Seok; Sappington, Thomas W; Allen, Charles T

2008-12-01

Thirty-seven boll weevils, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), were captured in pheromone traps near Lubbock, TX, in the Southern High Plains/Caprock eradication zone during August-October 2006. No boll weevils had been captured in this zone or neighboring zones to the north earlier in the year, and only very low numbers had been captured in neighboring zones to the south and east. Therefore, the captures near Lubbock were unexpected. Five of the weevils captured the last week of August were preserved and genotyped at 10 microsatellite loci for comparison with a database of genotypes for 22 boll weevil populations sampled from eight U.S. states and four locations in Mexico. The Lubbock population itself is an unlikely source, suggesting that the captured weevils probably did not originate from a low-level endemic population. Populations from eastern states, Mexico, and Big Spring, TX, can be confidently excluded as potential source regions. Although the Weslaco and Kingsville, TX, areas cannot be statistically excluded, they are unlikely sources. The most likely sources are nearby areas in New Mexico, TX, or southwest Oklahoma, or from areas of eastern Texas represented by Waxahachie and El Campo populations. Together, genetic and circumstantial evidence suggest either that the trapped boll weevils are the offspring of alone mated female that immigrated from eastern Texas earlier in the summer or that weevils originally captured near Waxahachie but now long-dead were planted in the traps by a disgruntled employee of the eradication program.

Genetic variation of white clover ( Trifolium repens L.) collections ...

African Journals Online (AJOL)

amplified polymorphic DNA (RAPD) and simple sequence repeat (SSR) to investigate the genetic relationships among white clover germplasms of China, and four commercial cultivars were included for a comparison. The results revealed that the populations showed diverse morphological traits, RAPD and SSR patterns.

Boll weevil (Coleoptera: Curculionidae) response to and volatilization rates of grandlure when combined with varying doses of eugenol in the extended-life pheromone lure.

Science.gov (United States)

Armstrong, J S

2010-04-01

Boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), trapping and pheromone quantitative analysis of extended-life pheromone lures manufactured with 0, 10, 20, and 30 mg of eugenol was conducted in the Rio Grande Valley of Texas under spring and summer conditions. Boll weevils responded positively to eugenol on one of 12 trapping weeks when densities were high, but when densities were low (30 degrees C, accumulative grandlure loss per week may be too high, leaving too little residual grandlure to effectively attract boll weevils at the end of 3 wk of trapping. Eugenol plays no role in reserving or encouraging the release of grandlure, or in increasing boll weevil captures when boll weevil densities are low.

Replication of Chilo iridescent virus in the cotton boll weevil, Anthonomus grandis, and development of an infectivity assay.

Science.gov (United States)

Henderson, C W; Johnson, C L; Lodhi, S A; Bilimoria, S L

2001-01-01

The boll weevil, Anthonomus grandis Boheman, is a devastating pest of cotton. Chemical pesticides are problematic due to relative lack of target specificity and resistance. Microbial pesticides may provide viable alternatives because of their narrow host range. Chilo iridescent virus (CIV) is the type species for genus Iridovirus, family Iridoviridae: large, icosahedral cytoplasmic viruses containing a double-stranded DNA genome. Earlier work suggested that CIV replicated in the boll weevil; however, efficiency or production of infectious virus was not established. We showed that CIV undergoes a productive cycle in A. grandis. CIV DNA levels in boll weevil pupae increased significantly from 0 to 3 days post infection. Moreover, virogenic stromata and complete virus particles were observed in the cytoplasm by 7 days. An endpoint dilution assay using viral DNA replication as indicator suggested a 10(5)-fold increase in infectious virus titer over 7 days. This is the first such demonstration in larval infections with genus Iridovirus. Our study establishes that CIV undergoes a productive cycle in the boll weevil and provides an important and useful model system for replication at the organismal level. These results have important implications for the potential of CIV and its components in boll weevil control.

Influence of Rice Seeding Rate on Efficacies of Neonicotinoid and Anthranilic Diamide Seed Treatments against Rice Water Weevil

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Jason Hamm

2014-12-01

Full Text Available Rice in the U.S. is frequently seeded at low rates and treated before sowing with neonicotinoid or anthranilic diamide insecticides to target the rice water weevil. A previous study of the influence of seeding rate on rice water weevil densities showed an inverse relationship between seeding rates and immature weevil densities. This study investigated interactive effects of seeding rate and seed treatment on weevil densities and rice yields; in particular, experiments were designed to determine whether seed treatments were less effective at low seeding rates. Four experiments were conducted over three years by varying seeding rates of rice treated at constant per seed rates of insecticide. Larval suppression by chlorantraniliprole was superior to thiamethoxam or clothianidin, and infestations at low seeding rates were up to 47% higher than at high seeding rates. Little evidence was found for the hypothesis that seed treatments are less effective at low seeding rates; in only one of four experiments was the reduction in weevil densities by thiamethoxam greater at high than at low seeding rates. However, suppression of larvae by neonicotinoid seed treatments in plots seeded at low rates was generally poor, and caution must be exercised when using the neonicotioids at low seeding rates.

INVESTIGATIONS ON THE RESISTANCE OF SOME BULGARIAN COMMON BEAN GENOTYPES TOWARDS BEAN WEEVIL (ACANTHOSCELIDES OBTECTUS SAY

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Elena Dimitrova Apostolova

2013-12-01

Full Text Available The most effective, environmentally sound and safety way to fight pests with biological means is the use of resistant varieties to them. In the present study were indicated the reactions of 30 Bulgarian common bean genotypes to the most economically important enemy – bean weevil (Acanthoscelidis obtectus Say. For this purpose, the following indicators were traced – seed damages and young adult insects, which largely characterized the response of different common bean genotypes to that biological pest enemy. The results of this investigation present a sensitive response to the sustainability of different genotypes to the bean weevil. The Bulgarian common bean varieties Plovdiv 11M, Abritus, Crystal and Bulgari can be used in breeding programs as donors of resistance to the bean weevil.

Soil properties and clover establishment six years after surface application of calcium-rich by-products

Energy Technology Data Exchange (ETDEWEB)

Ritchey, K.D.; Belesky, D.P.; Halvorson, J.J. [USDA ARS, Beaver, WV (US). Appalachian Farming Systems Research Center

2004-12-01

Calcium-rich soil amendments can improve plant growth by supplying Ca and reducing detrimental effects of soil acidity, but solubility and neutralizing capacity of Ca sources vary. Our objectives were to evaluate effects of calcitic dolomite and several coal combustion by-products on soil properties at various depths 6 yr after surface application and their influence on grass-clover herbage accumulation. Calcium and Mg soil amendments were surface-applied to an acidic grassland in 1993, and orchardgrass (Dactylis glomerata L.) and tall fescue (Lolium arundinaceum (Schreb.) Darbyshire) were oversown in 1994. In 1998, amendment treatment plots were split to accommodate sod seeding with red clover (Trifolium pratense L.) or white clover (T. repens L.) as well as a nonseeded control. No N fertilizer was applied after sod seeding. Six years after amendment application, reductions in soil Al and Mn and increases in Ca and pH from 4654 kg ha{sup -1} calcitic dolomite, 15 000 kg ha{sup -1} fluidized bed combustion residue, or 526 kg ha{sup -1} MgO amendment were greatest in the surface 2.5 cm while rates of gypsum as high as 32 000 kg ha{sup -1} left little residual effect except for decreases in Mg. Percentage clover in the sward tripled as pH increased from 4.3 to 5.0 while herbage mass increased 75% as clover percentage increased. Herbage mass was generally more closely correlated with properties of soil samples collected from the surface 2.5 cm than from deeper samples.

Effects of field characteristics on abundance of bumblebees (Bombus spp.) and seed yield in red clover fields

DEFF Research Database (Denmark)

Wermuth, Kirsten Haugaard; Dupont, Yoko L.

2010-01-01

Red clover is a key floral ressource for bumblebees (Bombus spp.).We here investigate variation within and among red clover fields in species richness and abundance of Bombus spp. in addition to Apis mellifera. Bumblebee individuals were grouped into the following functional groups, based on castes...

Mitigation of salt stress in white clover (Trifolium repens) by Azospirillum brasilense and its inoculation effect.

Science.gov (United States)

Khalid, Muhammad; Bilal, Muhammad; Hassani, Danial; Iqbal, Hafiz M N; Wang, Hang; Huang, Danfeng

2017-12-01

Salinity is one of the increasingly serious environmental problems worldwide for cultivating agricultural crops. The present study was aimed to ascertain the potential of beneficial soil bacterium Azospirillum brasilense to alleviate saline stress in Trifolium repens. Experimental plants (white clover) were grown from seeds and inoculated with or without A. brasilense bacterial strain supplemented with 0, 40, 80, or 120 mM NaCl into soil. The growth attributes including, shoot heights, root lengths, fresh and dry weights, leaf area and chlorophyll content were significantly enhanced in T. repens plants grown in A. brasilense inoculated soil than un-inoculated controls, particularly under elevated salinity conditions (40, 80 and 120 mM NaCl). Malondialdehyde content of leaf was recorded to be declined under saline conditions. Moreover, the K + /Na + ratio was also improved in bacterium-inoculated plants, since A. brasilense significantly reduced the root and shoot Na + level under high salty environment. Results revealed that soil inoculation with A. brasilense could significantly promote T. repens growth under both non-saline and saline environments, and this study might be extended to other vegetables and crops for the germination and growth enhancement.

Effects of grass-clover management and cover crops on nitrogen cycling and nitrous oxide emissions in a stockless organic crop rotation

DEFF Research Database (Denmark)

Brozyna, Michal Adam; Petersen, Søren O; Chirinda, Ngoni

2013-01-01

Nitrogen (N) supply in stockless organic farming may be improved through use of grass-clover for anaerobic digestion, producing biogas and digested manure for use as fertilizer in the crop rotation. We studied the effects of grass-clover management on N cycling, nitrous oxide (N2O) emissions...... in the rotation (spring barley, potato and winter wheat); actual digestion of grass-clover cuttings was not possible, instead digested pig manure was used as substitute for digested grass-clover. Nitrous oxide fluxes were monitored between April 2008 and May 2009. In general, application of digested manure had...

Rational Practices to Manage Boll Weevils Colonization and Population Growth on Family Farms in the Semiárido Region of Brazil.

Science.gov (United States)

Neves, Robério C S; Colares, Felipe; Torres, Jorge B; Santos, Roberta L; Bastos, Cristina S

2014-10-31

Because boll weevil, Anthonomus grandis Boh. develops partially protected inside cotton fruiting structures, once they become established in a field, they are difficult to control, even with nearly continuous insecticide spray. During two cotton-growing seasons in the Semiárido region of Pernambuco State, Brazil, we tested the use of kaolin sprays to disrupt plant colonization through visual cue interference, combined with removal of fallen fruiting bodies to restrain boll weevil population growth after colonization. Kaolin spray under non-choice trials resulted in 2.2×, 4.4×, and 8.6× fewer weevils, oviposition and feeding punctures on kaolin-treated plants, respectively, despite demonstrating no statistical differences for colonization and population growth. Early season sprays in 2010 occurred during a period of rainfall, and hence, under our fixed spraying schedule no significant differences in boll weevil colonization were detected. In 2011, when kaolin sprays were not washed out by rain, delayed boll weevil colonization and reduction on attacked fruiting bodies were observed in eight out of 12 evaluations, and kaolin-treated plots had 2.7× fewer damaged fruiting bodies compared to untreated plots. Adoption of simple measures such as removal of fallen fruiting bodies and prompt reapplication of kaolin sprays after rainfall show promise in reducing boll weevil infestation.

Studies on food preferences of maize weevil, Sitophilus zeamais Mots. to different crops in Chitwan, Nepal

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Sheela Devi Sharma

2016-12-01

Full Text Available Food preference by the maize weevil, Sitophilus zeamais Motschulsky was studied on seven different crops and varieties including maize, wheat and rice. They were maize cultivars namely Arun-2, Manakamana-4, Deuti, buckwheat local cultivar, wheat cultivar namely Annapurna-1, polished rice-Radha 4 and unshelled rice cultivar Mansuli under storage condition at Institute of Agriculture and Animal Science, Rampur, Chitwan, Nepal from June 2013 to February 2014 . The hosts were tested using completely randomized design with three replications and were laid in free-choice and no-choice conditions. The maximum number of grain loss was recorded in wheat followed by polished rice respectively. Similarly, the highest weight loss was recorded in polished rice followed by Wheat in both conditions. F1 progeny emergence of weevil was highest in wheat followed by polished rice in free-choice and in no choice conditions, the highest progeny were emerged from polished rice followed by wheat. The lowest numbers of weevils emerged from rice in both conditions. Maximum germination losses were recorded in wheat (24.33% and lowest in Arun-2 (9.67. The rice showed a relatively higher preference to maize weevil under storage condition.

Feeding deterrent compounds to the boll weevil,Anthonomus grandis Boheman in Rose-of-Sharon,Hibiscus syriacus L.

Science.gov (United States)

Bird, T G; Hedin, P A; Burks, M L

1987-05-01

The Rose-of-Sharon,Hibiscus syriacus (L.), can be a significant alternate host plant for the boll weevil,Anthonomus gradis (Boh.). Boll weevils are known to be deterred from feeding and ovipositing in the buds unless the calyx is removed. This investigation was initiated to identify calyx allelochemicals that deter feeding with the eventual strategy of breeding for cotton lines high in these allelochemicals in the appropriate tissues. The feeding deterrency of calyx tissue from the buds of Rose-of-Sharon for the boll weevil was confirmed. The most active deterrent fraction was found to contain mostly fatty acids and their methyl esters. Saturated fatty acids and their methyl esters were generally found to be stimulatory, while the unsaturated species were found to be deterrent. Higher quantities of the fatty acids, particularly the unsaturated species, were found in Rose-of-Sharon calyx tissue than in the buds without calyx. This supports the hypothesis developed through the isolational work and testing of standards that the unsaturated fatty acids are significant deterrents of boll weevil feeding.

Molecular cloning of a cysteine proteinase cDNA from the cotton boll weevil Anthonomus grandis (Coleoptera: Curculionidae).

Science.gov (United States)

De Oliveira Neto, Osmundo Brilhante; Batista, João Aguiar Nogueira; Rigden, Daniel John; Franco, Octávio Luiz; Fragoso, Rodrigo Rocha; Monteiro, Ana Carolina Santos; Monnerat, Rose Gomes; Grossi-De-Sa, Maria Fátima

2004-06-01

The cotton boll weevil (Anthonomus grandis) causes severe cotton crop losses in North and South America. This report describes the presence of cysteine proteinase activity in the cotton boll weevil. Cysteine proteinase inhibitors from different sources were assayed against total A. grandis proteinases but, unexpectedly, no inhibitor tested was particularly effective. In order to screen for active inhibitors against the boll weevil, a cysteine proteinase cDNA (Agcys1) was isolated from A. grandis larvae using degenerate primers and rapid amplification of cDNA ends (RACE) techniques. Sequence analysis showed significant homologies with other insect cysteine proteinases. Northern blot analysis indicated that the mRNA encoding the proteinase was transcribed mainly in the gut of larvae. No mRNA was detected in neonatal larvae, pupae, or in the gut of the adult insect, suggesting that Agcys1 is an important cysteine proteinase for larvae digestion. The isolated gene will facilitate the search for highly active inhibitors towards boll weevil larvae that may provide a new opportunity to control this important insect pest.

Effects of gamma radiation on the response of the rice weevil, sitophilus oryzae to heat and humidity

International Nuclear Information System (INIS)

Wakid, A.M.; Hilmy, N.M.; El-Monairy, O.M.

1991-01-01

The rice weevil, sitophilus oryzae L.was irradiated with 4 doses of gamma radiation (20,40,60 and 80 krad) and then examined for its response towards two different temperatures (45 and 25 degree C) or humidities (10 and 70% R.H.) For this purpose, two different apparatus were used. Each two temperature or humidity combinations were given to the weevils at the same time. The irradiated insects with 20 or 40 krad showed a marked increase in their speed at the warm side (45 degree C) than the controls. Those irradiated with 60 and 80 krad decreased their speed to about the control level. When the irradiated weevils were given the choice between 45 degree C and 25 degree C, their intensity of reaction towards the cooler side was decreased with increasing the doses. The rate of movement at 10% R.H. was not changed at 20 krad. However, at 40, 60 or 80 krad, it was increased with increasing the dose. The intensity of reaction of the irradiated weevils increased towards the dry side with increasing the dose.2 tab

Phyto-oestrogens in herbage and milk from cows grazing whiteclover, red clover, lucerne or chicory-rich pastures

DEFF Research Database (Denmark)

Andersen, C; Nielsen, T S; Purup, S

2009-01-01

A grazing experiment was carried out to study the concentration of phyto-oestrogens in herbage for cattle and in milk during two periods (May and June). Forty-eight Danish Holstein cows were divided into four groups with four treatment diets; white clover, red clover, lucerne and chicory-rich pas...

Pea weevil damage and chemical characteristics of pea cultivars determining their resistance to Bruchus pisorum L.

Science.gov (United States)

Nikolova, I

2016-04-01

Bruchus pisorum (L.) is one of the most intractable pest problems of cultivated pea in Europe. Development of resistant cultivars is very important to environmental protection and would solve this problem to a great extent. Therefore, the resistance of five spring pea cultivars was studied to B. pisorum: Glyans, Modus; Kamerton and Svit and Pleven 4 based on the weevil damage and chemical composition of seeds. The seeds were classified as three types: healthy seeds (type one), damaged seeds with parasitoid emergence holes (type two) and damaged seeds with bruchid emergence holes (type three). From visibly damaged pea seeds by pea weevil B. pisorum was isolated the parasitoid Triaspis thoracica Curtis (Hymenoptera, Braconidae). Modus, followed by Glyans was outlined as resistant cultivars against the pea weevil. They had the lowest total damaged seed degree, loss in weight of damaged seeds (type two and type three) and values of susceptibility coefficients. A strong negative relationship (r = -0.838) between the weight of type one seeds and the proportion of type three seeds was found. Cultivars with lower protein and phosphorus (P) content had a lower level of damage. The crude protein, crude fiber and P content in damaged seeds significantly or no significantly were increased as compared with the healthy seeds due to weevil damage. The P content had the highest significant influence on pea weevil infestation. Use of chemical markers for resistance to the creation of new pea cultivars can be effective method for defense and control against B. pisorum.

Sterilization of boll weevil pupae with fractionated doses of gamma irradiation

International Nuclear Information System (INIS)

Haynes, J.W.; Mitlin, N.; Davich, T.B.; Dawson, J.R.; McGovern, W.L.; McKibben, G.H.

1977-01-01

Fractionated doses of 6,250-8,000 rads of gamma irradiation administered to pupae of the boll weevil, Anthonomus grandis Boh., sexually sterilized both sexes. Mortality of males thus treated with 6,250 and 8,000 rads via fractionation was 14% and 27% respectively, by 5 days posttreatment compared with 46% mortality when an equivalent acute dose was administered to newly emerged adults. Pheromone production of males irradiated at 6,250 rads was one-third that of the control for the first 4 days, but equal that of the control during 5-11 days posttreatment. This procedure lends itself to the large-scale sterilization of weevils needed in an eradication program. This technique is applicable to other insects that are highly susceptible to acute doses

Improving Resilience of Northern Field Crop Systems Using Inter-Seeded Red Clover: A Review

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William Deen

2013-02-01

Full Text Available In light of the environmental challenges ahead, resilience of the most abundant field crop production systems must be improved to guarantee yield stability with more efficient use of nitrogen inputs, soil and water resources. Along with genetic and agronomic innovations, diversification of northern agro-ecosystems using inter-seeded legumes provides further opportunities to improve land management practices that sustain crop yields and their resilience to biotic and abiotic stresses. Benefits of legume cover crops have been known for decades and red clover (Trifolium pratense is one of the most common and beneficial when frost-seeded under winter wheat in advance of maize in a rotation. However, its use has been declining mostly due to the use of synthetic fertilizers and herbicides, concerns over competition with the main crop and the inability to fully capture red clover benefits due to difficulties in the persistence of uniform stands. In this manuscript, we first review the environmental, agronomic, rotational and economical benefits associated with inter-seeded red clover. Red clover adaptation to a wide array of common wheat-based rotations, its potential to mitigate the effects of land degradation in a changing climate and its integration into sustainable food production systems are discussed. We then identify areas of research with significant potential to impact cropping system profitability and sustainability.

Ethnobotanicals for Storage Pest Management: Effect of powdered leaves of Olax zeylanica in suppressing infestations of rice weevil Sitophilus oryzae (Coleoptera: Curculionidae

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Sachini Dinusha Fernando

2012-05-01

Full Text Available Abstract The rice weevil Sitophilus oryzae is considered the major problem in stored rice in Sri Lanka. Due to the adverse effects of pesticide usage, research on the re-evaluation and use of many ethnobotanicals as alternative storage pest control agents has been intensified. Although plant materials with insecticidal properties provide small-scale farmers with a locally available, eco-friendly and inexpensive method of control of storage insect pests, lack of understanding and knowledge prevent their widespread application. The present study was therefore undertaken to investigate the effectiveness of the botanical Olax zeylanica in controlling infestations of the rice weevil with the view of fulfilling this lack. In two separate bioassays, contact/feeding and fumigant toxicity of powdered leaves of O. zeylanica were tested against 1-7 days old adults under laboratory conditions. All experiments were conducted using a no-choice bioassay apparatus. Contact/feeding toxicity was tested by directly exposing weevils to 1.0, 3.0, 5.0 and 7.5g of leaf powder mixed with 100g of rice grains while fumigant toxicity was evaluated by using the same doses where weevils were exposed to fumes emitted from the leaf powders. In both bioassays 100% mortality of the weevils was observed within 18 hours of exposure to 3.0, 5.0 and 7.5g doses of leaf powder. Percentage weevil mortality in treated rice tested with three doses of leaf powder at all the time intervals (except for 1.0g was significantly higher (p < 0.05 than that of the corresponding control. No Contact/feeding toxicity was recorded when weevils were directly exposed to 1.0g leaf powder whereas only 14% weevil mortality was observed even after 24hours of exposure to fumes of leaf powder. Results also revealed that weevil mortality increased both with increasing dose and time of exposure. It is of interest to note that in both bioassays a 100% weevil mortality was obtained after 18 hours of exposure to

Assessment of Qualitative and Quantitative Characters of Two Persian Clover Ecotypes Inoculated by Rhizobium leguminosarum biovartrifoli and Pesudomonas putida Bacteria

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R Azamei

2016-02-01

to an increase in the growth of quantitative traits. Inoculation with Rhizobium and Pseudomonas putida in most of the cases combined with the highest growth and treatments without inoculation (control had the lowest growth as well. Dilip Kumar et al. (1 demonstrated that the combined inoculation of pea seeds with Rhizobium and Pseudomonas leads to an increase in plant height, root length and dry weight compared to control treatments. However the present study has shown the positive impacts of biological fertilizers on some of the growth parameters, but the important thing is the proper use of biological fertilizers. It was also concluded that the date of planting in spring is very important and delayed planting can affect forage quality. Conclusions This study showed that biofertilizers can have positive effects on growth characters of clover, and requires more research.

Preliminary research on amino acid composition and nutritional value of clover proteins

Directory of Open Access Journals (Sweden)

L. Kłyszejko-Stefanowicz

2015-06-01

Full Text Available The amino acid composition and nutritional value of 5 clover varieties including 3 Polish ones ('Gloria', 'Hruszowska', 'Skrzeszowicka' and 2 of foreign origin ('Rotra' and 'Violetta' were investigated. No significant differences in the total protein content (19.2–20.0% of dry matter as well as in qualitative amino acid composition were found among the clover varieties under examination. EAA index (Essential amino acid index calculated according to Oser for 'Gloria' and 'Hruszowska' showed the highest nutritional value was – 40. The lowest value of EAA index was found for 'Violetta' cvar. – 32, intermediate values however for Rotra and Skrzeszowicka was 37 and 36.

Analysis of the effects of pair production for the suppressed clover detector

International Nuclear Information System (INIS)

Kshetri, R.

2014-01-01

Full energy peak, single escape peak and double escape peak areas have been extracted for an escape suppressed clover detector. Results have been obtained for the single crystal and addback modes of operation as well as the active and passive suppression cases at several gamma energies. We have compared the ratio of single escape peak areas in addback mode with that of single crystal mode to study if the single escape peak gains or loses counts due to addback mode. Detailed analysis has been performed for quantifying the advantages of using addback mode and active suppression. Comparison is made for different types of clover detectors with different volumes

Molecular evolution of the Li/li chemical defence polymorphism in white clover (Trifolium repens L.).

Science.gov (United States)

Olsen, K M; Sutherland, B L; Small, L L

2007-10-01

White clover (Trifolium repens) is naturally polymorphic for cyanogenesis (hydrogen cyanide release following tissue damage). The ecological factors favouring cyanogenic and acyanogenic plants have been examined in numerous studies over the last half century, making this one of the best-documented examples of an adaptive polymorphism in plants. White clover cyanogenesis is controlled by two, independently segregating Mendelian genes: Ac/ac controls the presence/absence of cyanogenic glucosides; and Li/li controls the presence/absence of their hydrolysing enzyme, linamarase. In this study, we examine the molecular evolution and population genetics of Li as it relates to the cyanogenesis polymorphism. We report here that Li exists as a single-copy gene in plants possessing linamarase activity, and that the absence of enzyme activity in li/li plants is correlated with the absence of much or all of the gene from the white clover genome. Consistent with this finding, we confirm by reverse transcription-polymerase chain reaction that Li gene expression is absent in plants lacking enzyme activity. In a molecular population genetic analysis of Li and three unlinked genes using a worldwide sample of clover plants, we find an absence of nucleotide variation and statistically significant deviations from neutrality at Li; these findings are consistent with recent positive directional selection at this cyanogenesis locus.

Microbiological quality of raw and roasted African palm weevil ...

African Journals Online (AJOL)

Microbiological quality of raw and roasted African palm weevil ( Rhynchophorus phoenicis ) consumed in the south eastern Nigeria. ... Rhynchophorus phoenicis though reported to be highly nutritious in terms of amino acid profile and presence of unsaturated fatty acid can be a source of food poison if not properly handled ...

Efficacy of Topical Application, Leaf Residue or Soil Drench of Blastospores of Isaria fumosorosea for Citrus Root Weevil Management: Laboratory and Greenhouse Investigations

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Pasco B. Avery

2016-11-01

Full Text Available The efficacy of topical, leaf residue, and soil drench applications with Isaria fumosorosea blastospores (Ifr strain 3581 was assessed for the management of the citrus root weevil, Diaprepes abbreviatus (L.. Blastospores of Ifr were applied topically at a rate of 107 blastospores mL−1 on both the larvae and adults, and each insect stage was incubated in rearing cups with artificial diet at 25 °C, either in the dark or in a growth chamber under a 16 h photophase for 2 weeks, respectively. Percent larval and adult mortality due to the infection of Ifr was assessed after 14 days as compared to untreated controls. Leaf residue assays were assessed by feeding the adults detached citrus leaves previously sprayed with Ifr (107 blastospores mL−1 in Petri dish chambers and then incubating them at 25 °C for 2–3 weeks. Efficacy of the soil drench applications was assessed on five larvae feeding on the roots of a Carrizo hybrid citrus seedling ~8.5–10.5 cm below the sterile sand surface in a single 16 cm × 15.5 cm pot inside a second pot lined with plastic mesh to prevent escapees. Drench treatments per pot consisted of 100 mL of Ifr suspension (107 blastospores mL−1, flushed with 400, 900, or 1400 mL of water compared to 500, 1000, and 1500 mL of water only for controls. The mean concentration of Ifr propagules as colony forming units per gram (CFUs g−1 that leached to different depths in the sand profile per treatment drench rate was also determined. Two weeks post-drenching of Ifr treatments, larvae were assessed for percent mortality, size differences, and effect of treatments in reducing feeding damage to the plant root biomass compared to the controls. Topical spray applications caused 13 and 19% mortality in larvae and adults after 7 days compared to none in the control after 14 days, respectively. Adults feeding on a single Ifr treated leaf for 24 h consumed less than the control, and resulted in 100% mortality 35 days post

Toxicity to cotton boll weevil Anthonomus grandis of a trypsin inhibitor from chickpea seeds.

Science.gov (United States)

de P G Gomes, Angélica; Dias, Simoni C; Bloch, Carlos; Melo, Francislete R; Furtado, José R; Monnerat, Rose G; Grossi-de-Sá, Maria F; Franco, Octávio L

2005-02-01

Cotton (Gossypium hirsutum L.) is an important agricultural commodity, which is attacked by several pests such as the cotton boll weevil Anthonomus grandis. Adult A. grandis feed on fruits and leaf petioles, reducing drastically the crop production. The predominance of boll weevil digestive serine proteinases has motivated inhibitor screenings in order to discover new ones with the capability to reduce the digestion process. The present study describes a novel proteinase inhibitor from chickpea seeds (Cicer arietinum L.) and its effects against A. grandis. This inhibitor, named CaTI, was purified by using affinity Red-Sepharose Cl-6B chromatography, followed by reversed-phase HPLC (Vydac C18-TP). SDS-PAGE and MALDI-TOF analyses, showed a unique monomeric protein with a mass of 12,877 Da. Purified CaTI showed significant inhibitory activity against larval cotton boll weevil serine proteinases (78%) and against bovine pancreatic trypsin (73%), when analyzed by fluorimetric assays. Although the molecular mass of CaTI corresponded to alpha-amylase/trypsin bifunctional inhibitors masses, no inhibitory activity against insect and mammalian alpha-amylases was observed. In order to observe CaTI in vivo effects, an inhibitor rich fraction was added to an artificial diet at different concentrations. At 1.5% (w/w), CaTI caused severe development delay, several deformities and a mortality rate of approximately 45%. These results suggested that CaTI could be useful in the production of transgenic cotton plants with enhanced resistance toward cotton boll weevil.

White clover fractions as protein source for monogastrics - Dry matter digestibility and Protein Digestibility-Corrected Amino Acid Scores

DEFF Research Database (Denmark)

Stødkilde, Lene; Damborg, Vinni K; Jørgensen, Henry

2018-01-01

BACKGROUND: The aim was to evaluate white clover as an alternative protein source for monogastrics. White clover plant and leaves were processed using a screw-press resulting in a solid pulp and a juice from which protein was acid-precipitated. The chemical composition of all fractions...... was determined and digestibility of dry matter (DM) and protein was assessed in an experiment with growing rats. RESULTS: Protein concentrates were produced with crude protein (CP) content of 451 g/kg DM and 530 g/kg DM for white clover plant and leaves, respectively and a pulp with CP content of 313 and 374 g...

The use of aggregation pheromone to enhance dissemination of Beauveria bassiana for the control of the banana weevil in Uganda

NARCIS (Netherlands)

Tinzaara, W.; Gold, C.S.; Dicke, M.; Huis, van A.; Nankinga, C.M.; Kagezi, G.H.; Ragama, P.E.

2007-01-01

Candidate strains of Beauveria bassiana were identified for use in integrated pest management of the banana weevil Cosmopolites sordidus. Horizontal field transmission of B. bassiana between banana weevils using different delivery systems, including aggregation pheromones, was investigated. We

Effects of Temperature and Adult Diet on Development of Hypertrophied Fat Body in Prediapausing Boll Weevil (Coleoptera Curculionidae)

Science.gov (United States)

Terence L. Wagner; Eric J. Villavaso

1999-01-01

This study examines the effects of temperature and adult diet on the development of hypertrophied fat bodies in prediapausing adult boll weevils, Anthonomus grandis grandis Boheman. Simulation models derived from this work are used to estimate the minimal ages at which male and female boll weevils exhibit diapause morphology, based on conditions...

Rational Practices to Manage Boll Weevils Colonization and Population Growth on Family Farms in the Semiárido Region of Brazil

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Robério C. S. Neves

2014-10-01

Full Text Available Because boll weevil, Anthonomus grandis Boh. develops partially protected inside cotton fruiting structures, once they become established in a field, they are difficult to control, even with nearly continuous insecticide spray. During two cotton-growing seasons in the Semiárido region of Pernambuco State, Brazil, we tested the use of kaolin sprays to disrupt plant colonization through visual cue interference, combined with removal of fallen fruiting bodies to restrain boll weevil population growth after colonization. Kaolin spray under non-choice trials resulted in 2.2×, 4.4×, and 8.6× fewer weevils, oviposition and feeding punctures on kaolin-treated plants, respectively, despite demonstrating no statistical differences for colonization and population growth. Early season sprays in 2010 occurred during a period of rainfall, and hence, under our fixed spraying schedule no significant differences in boll weevil colonization were detected. In 2011, when kaolin sprays were not washed out by rain, delayed boll weevil colonization and reduction on attacked fruiting bodies were observed in eight out of 12 evaluations, and kaolin-treated plots had 2.7× fewer damaged fruiting bodies compared to untreated plots. Adoption of simple measures such as removal of fallen fruiting bodies and prompt reapplication of kaolin sprays after rainfall show promise in reducing boll weevil infestation.

Genetic variation of white clover (Trifolium repens L.) collections ...

African Journals Online (AJOL)

STORAGESEVER

2010-05-24

May 24, 2010 ... incompatibility mechanism of disomic inheritance (Thomas,. 1987). In essence ..... Badr A, Sayed-Ahmed H, El-Shanshouri A, Watson LE (2002). Ancestors of white ... Caradus JR, Woodfield DR (1997). World checklist of ... within a natural population of white clover (Trifolium repense L). J. Ecol. 73: 615-624 ...

Growth of bermudagrass with white clover or nitrogen fertilizer

Science.gov (United States)

White clover (Trifolium repens) var ‘Durana’ was oversown into established bermudagrass (Cynodon dactylon) in 2009. Soil analysis indicated potassium (K) was low and potash at 112 and 336 kg/ha was added as main plots. Nitrogen as ammonium nitrate or an ammonium sulfate/urea blend was added as 0, 34...

Oviposition Decision of the Weevil Exapion ulicis on Ulex europaeus Depends on External and Internal Pod Cues

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Jean-Sébastien Pierre

2013-09-01

Full Text Available Understanding mechanisms underlying insects’ host choice and plant susceptibility is important to the study of plant-insect interactions in general, and in the context of plant invasions. This study investigates the oviposition and feeding choices of the specialist weevil Exapion ulicis on the invasive plant species Ulex europaeus, gorse. To do so, we studied the oviposition and feeding preferences of the weevil in choice experiments, using pods and flowers, respectively, from gorses grown in a common garden. The plants used came from regions with different infestation histories: Brittany and Scotland belong to the native range, where the weevil is present, while Reunion and New Zealand belong to the invasive range, where the weevil was not initially introduced with gorse. Results of these experiments suggest that the oviposition choice of E. ulicis females is driven by cues located at the surface of pods and inside them, including pod size and pod seed content. Feeding-choice experiments showed a different pattern of preference compared to oviposition. Taken together with previous studies, our results reveal that E. ulicis uses several traits to choose its host, including whole-plant traits, flower traits and pod traits.

Effects of two pheromone trap densities against banana weevil Cosmopolites sordidus, populations and their impact on plant damage in Uganda

NARCIS (Netherlands)

Tinzaara, W.; Gold, C.S.; Kagezi, G.H.; Dicke, M.; Huis, van A.; Nankinga, C.; Tushemereirwe, W.; Ragama, P.E.

2005-01-01

An on-farm study to evaluate the effect of pheromone trap density on the population of the banana weevil, Cosmopolites sordidus (Germar) (Col., Curculionidae) was conducted in Masaka district, Uganda. The pheromone used was Cosmolure+, a commercially available weevil aggregation pheromone. Forty-two

Irradiated boll weevils: pheromone production determined by GLC analysis

International Nuclear Information System (INIS)

McGovern, W.L.; McKibben, G.H.; Gueldner, R.C.; Cross, W.H.

1975-01-01

The production of pheromone by Anthonomus grandis Boheman when treated with 10,000 rad of 60 Co gamma irradiation compared favorably with that of control weevils for 5 days; however, feeding (determined by frass collection) was reduced from day one. No direct correlation was found between production of pheromone and elimination of frass

Is the Invasive Species Listronotus bonariensis (Kuschel) (Coleoptera: Curculionidae) (Argentine Stem Weevil) a Threat to New Zealand Natural Grassland Ecosystems?

Science.gov (United States)

Barratt, Barbara I P; Barton, Diane M; Philip, Bruce A; Ferguson, Colin M; Goldson, Stephen L

2016-01-01

Listronotus bonariensis (Argentine stem weevil) is a stem-boring weevil that has become a major pasture pest in New Zealand, and cool climate turf grass in Australia. This species is also frequently found in native tussock grassland in New Zealand. Laboratory and field trials were established to determine the risk posed to both seedlings and established plants of three native grass species compared to what happens with a common host of this species, hybrid ryegrass (L. perenne X L. multiflorum). Adult weevil feeding damage scores were higher on Poa colensoi and Festuca novae-zelandiae than Chionochloa rigida. Oviposition was lower on P. colensoi than hybrid ryegrass, and no eggs were laid on F. novae-zelandiae. In field trials using the same four species established as spaced plants L. bonariensis laid more eggs per tiller in ryegrass in a low altitude pasture site than in ryegrass in a higher altitude site. No eggs were found on the three native grass species at the tussock sites, and only low numbers were found on other grasses at the low altitude pasture site. Despite this, numbers of adult weevils were extracted from the plants in the field trials. These may have comprised survivors of the original weevils added to the plants, together with new generation weevils that had emerged during the experiment. Irrespective, higher numbers were recovered from the tussock site plants than from those from the pasture site. It was concluded that L. bonariensis is likely to have little overall impact, but a greater impact on native grass seedling survival than on established plants.

Cleaning the Soil from Zinc Using Red Clovers “Arimaičiai”

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Audronė Mikalajūnė

2011-02-01

Full Text Available Zinc as a nutrition element is required to plants in small quantities to maintain normal functions of metabolism mechanisms. Our work analyses the efficiency of red clovers “Arimaičiai” for cleaning zinc from the soil contaminated with zinc under laboratory conditions. Seeds were sown in three differently polluted soils: clean soil, once contaminated with zinc and periodically contaminated with zinc soil. Zinc concentration in one time contaminated soil was 45 mg/kg. After 6 months of phytoremediation, the remained zinc concentration in the soil was 3 times lower comparing with the initial concentration. It was also determined that under such conditions, the uptake of red clovers made approximately 65% of zinc. Permanent soil contamination with zinc increased concentration before phytoremediation up to 80 mg/kg. After 6 months of phytoremediation, zinc concentration was determined to be 1.9 times lower. Otherwise, the soil was permanently contaminated with larger zinc quantities and after application of which reached 300 mg/kg. In this case, following half a year of phytoremediation, zinc concentration in the soil was 1.7 times lower comparing with the initial concentration after contamination. It was determined that the uptake of red clovers made approximately 17% of zinc.Article in Lithuanian

The conundrum of chemical boll weevil control in subtropical regions

Science.gov (United States)

The boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), is a tropical Mesoamerican insect that invaded the United States in 1893, spreading across the Cotton Belt as the key pest of cotton and causing billions of dollars in yield losses and insecticide-based control efforts;...

Brilliant camouflage : photonic crystals in the diamond weevil, Entimus imperialis

NARCIS (Netherlands)

Wilts, Bodo D.; Michielsen, Kristel; Kuipers, Jeroen; Raedt, Hans De; Stavenga, Doekele G.

2012-01-01

The neotropical diamond weevil, Entimus imperialis, is marked by rows of brilliant spots on the overall black elytra. The spots are concave pits with intricate patterns of structural-coloured scales, consisting of large domains of three-dimensional photonic crystals that have a diamond-type

Kinetics and optimization of red clover pulp drying

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A. A. Shevtsov

2013-01-01

Full Text Available The kinetics of the drying process conducted with bagasse red clover on an experimental dry¬er superheated steam at atmospheric pressure in the active hydrodynamic regimes were study¬ing. The rational intervals of parameter changes were obtained. The problem of optimization, which allowed allocating the optimum range of variation of the input factors according to three criteria through compromise was solved.

A survey of the weevils of Ukraine (Coleoptera: Curculionoidea).

Science.gov (United States)

Yunakov, Nikolai; Nazarenko, Vitalij; Filimonov, Rostislav; Volovnik, Semyon

2018-04-05

The fauna of weevils Curculionoidea of Ukraine numbers 1453 species equivalent to 25.3% of European fauna. They belong to 10 families and 364 genera. A total of 51 species are recorded from Ukraine for the first time. Assessment of inventory completeness indicates that 62% of the area of Ukraine are covered by samples. Spatial join analysis has reveals strong collecting biases and shows maximal richness in cells which fall into well-sampled provinces. A total of 22 out of 33 studied model sites are well-sampled (C>0.5). In total, we estimate ca.1470 species of Curculionoidea living in Ukraine. Curculionidae comprise the majority (82%) of the fauna, with 1202 species and 266 genera, and with remarkably high proportion of the three largest subfamilies: Entiminae (26%), Curculioninae (19%), and Ceutorhynchinae (18%). Consolidated data analysis shows highest richness (678-822 spp.) in provinces which fall into the mountain areas. Aggregated species richness for each of five ecoregions uncovers highest values in Pontic steppe (665 species) and East European forest-steppe (593 species). Habitat distribution of weevils is strongly uneven. Most of the richness (565 spp.) is harboured in lowland broadleaf forests. Salt marshes, salt steppes and sands are extreme habitats with low richness but high proportion of habitat specialists. Only 141 dominant species representing 18% of the total fauna but make up to 63% of the total population of weevils in Ukraine. Endemic species comprise a small proportion of the fauna but are remarkably concentrated in the mountains of Crimea (24 species) and the Carpathians (25 species). Along with 'true' endemics, 210 species are narrowly-ranged non-endemics and also have higher concentration in Crimea and the Carpathians (105 and 38 spp.). A total of 82 species are qualified as widely-ranged with high concentration in Central European Mixed Forests and East European Forest Steppe (71 spp. on average per province).        The high

Salt tolerance in red clover (Trifolium pratense L.) seedlings

African Journals Online (AJOL)

Jane

2011-08-15

Aug 15, 2011 ... This study was conducted to investigate the effect of salt stress on germination of 28 red clover. (Trifolium pratense ... tolerance with the aim of improving crop plants (Zhu,. 2001) or soil .... The interaction of salinity and population in terms of PI ... in shoot growth is probably due to hormonal signals generated ...

Resistance of maize varieties to the maize weevil Sitophilus zeamais

African Journals Online (AJOL)

This study aimed at evaluating commonly used maize varieties, collected from Melkasa and Bako Agricultural Research Centers and Haramaya University, Ethiopia, against the maize weevil Sitophilus zeamais Motsch., one of the most important cosmopolitan stored product pests in maize. A total of 13 improved maize ...

Estimating impact on clover-grass yield caused by traffic intensities

DEFF Research Database (Denmark)

Jørgensen, R N; Green, Ole; Kristensen, Kristian

2009-01-01

Steer and a 15 m3 Kimadan slurry tanker on two axels, was used to perform the simulated traffic treatment on the parcels. The different traffic intensities are combinations of different tire pressure (1,0 and 2,5 bar), tire load (3000 and 6000 kg), time of year and number of passes (variating from 0 to 8...... components must be determined.   The objective of this paper was to measure yield affects on clover-grass as a consequence of different traffic intensities. The experiments were carried out in the context of a full scale field trial. A 14 hectare full scale grass-clover field trial with 24 different traffic......). The harvesting procedure was preformed with a Haldrup plot harvester modified with RTK-GPS. This paper shows the initial results from measuring the yield affects References M.A. Hamza, M.A.; Anderson, W.K 2005. Soil compaction in cropping systems: A review of the nature, causes and possible solutionsRaper , R...

Efficacy of fipronil aerially applied in oil adjuvants and drift retardants against boll weevils, Anthonomus Grandis Boheman (Coleoptera:Curculionidae)

Science.gov (United States)

Joseph E. Mulrooney

2002-01-01

Results of aerial application tests in the field and insecticide transfer tests in the laboratory showed that cottonseed oil was the most effective oil adjuvant to use with fipronil for controlling boll weevils under field conditions and for transferring fipronil from cotton leaf surfaces to boll weevils. The mineral oil and mineral oil + drift retardant more...

Host-plant preference and performance of the vine weevil Otiorhynchus sulcatus

NARCIS (Netherlands)

van Tol, R.W.H.M.; van Dijk, N.; Sabelis, M.W.

2004-01-01

The relationship between reproductive performance and preference for potential host plants of the vine weevil is investigated, as shown in tests on contact (or feeding) preference, presented herein, and tests on olfactory preference, published elsewhere. Assessment of reproductive performance shows

Host plant preference and performance of the vine weevil Otiorhynchus sulcatus

NARCIS (Netherlands)

Tol, van R.W.H.M.; Dijk, van N.; Sabelis, M.W.

2004-01-01

1. The relationship between reproductive performance and preference for potential host plants of the vine weevil is investigated, as shown in tests on contact (or feeding) preference, presented herein, and tests on olfactory preference, published elsewhere. 2. Assessment of reproductive performance

Detection and quantification of Leptographium wageneri, the cause of black-stain root disease, from bark beetles (Coleoptera: Scolytidae) in North California using regular and real-time PCR

Science.gov (United States)

Wolfgang Schweigkofler; William J. Otrosina; Sheri L. Smith; Daniel R. Cluck; Kevin Maeda; Kabir G. Peay; Matteo Garbelotto

2005-01-01

Black-stain root disease is a threat to conifer forests in western North America. The disease is caused by the ophiostomatoid fungus Leptographium wageneri (W.B. Kendr.) M.J. Wingf., which is associated with a number of bark beetle (Coleoptera: Scolytidae) and weevil species (Coleoptera: Curculionidae). We developed a polymerase chain reaction test...

Joseph Clover and the cobra: a tale of snake envenomation and attempted resuscitation with bellows in London, 1852.

Science.gov (United States)

Ball, C

2010-07-01

The Industrial Revolution saw the creation of many new jobs, but probably none more curious than that of zookeeper. The London Zoological Gardens, established for members in 1828, was opened to the general public in 1847. In 1852 the "Head Keeper in the Serpent Room", Edward Horatio Girling, spent a night farewelling a friend departing for Australia. He arrived at work in an inebriated state and was bitten on the face by a cobra that he was handling in a less than sensible manner. He was taken by cab to University College Hospital where he was resuscitated by a number of doctors, including Joseph Clover then the resident medical officer to the hospital and later to become the leading anaesthetist in London. Clover recorded this event in his diary along with the resuscitation method used. The patient eventually died but his treatment created a flurry of correspondence in the medical and lay press. Interestingly, the attempted resuscitation was with bellows, which had been abandoned by the Royal Humane Society twenty years earlier Clover records other cases of resuscitation with bellows at University College Hospital during his time as a resident medical officer there (1848 to 1853). There is a casebook belonging to Joseph Clover in the Geoffrey Kaye Museum, in Melbourne. This story is one of the many interesting stories uncovered during a study of this book and Clover's other personal papers.

Assessment of dietary ratios of red clover and corn silages on milk production and milk quality in dairy cows.

Science.gov (United States)

Moorby, J M; Ellis, N M; Davies, D R

2016-10-01

Twenty-four multiparous Holstein-Friesian dairy cows were used in a replicated 3×3 Latin square changeover design experiment to test the effects of changing from corn (Zea mays) silage to red clover (Trifolium pratense) silage in graded proportions on feed intakes, milk production, and whole-body N and P partitioning. Three dietary treatments with ad libitum access to 1 of 3 forage mixtures plus a standard allowance of 4kg/d dairy concentrates were offered. The 3 treatment forage mixtures were, on a dry matter (DM) basis: (1) R10: 90% corn silage and 10% red clover silage, (2) R50: 50% corn silage and 50% red clover silage, and (3) R90: 10% corn silage and 90% red clover silage. In each of 3 experimental periods, there were 21d for adaptation to diets, and 7d for measurements. Diet crude protein intakes increased, and starch intakes decreased, as the silage mixture changed from 90% corn to 90% red clover, although the highest forage DM intakes and milk yields were achieved on diet R50. Although milk fat yields were unaffected by diet, milk protein yields were highest with the R 0250 diet. Whole-body partitioning of N was measured in a subset of cows (n=9), and both the daily amount and proportion of N consumed that was excreted in feces and urine increased as the proportion of red clover silage in the diet increased. However, the apparent efficiency of utilization of feed N for milk protein production decreased from 0.33g/g for diet R10 to 0.25g/g for diet R90. The urinary excretion of purine derivatives (sum of allantoin and uric acid) tended to increase, suggesting greater flow of microbial protein from the rumen, as the proportion of red clover silage in the diet increased, and urinary creatinine excretion was affected by diet. Fecal shedding of E. coli was not affected by dietary treatment. In conclusion, even though microbial protein flow may have been greatest from the R 0450 diet, optimum feed intakes and milk yields were achieved on a diet that contained a

Classical Biological Control of Water Hyacinth, Eichhornia Crassipes (Liliales: Pomteridiaeae), Using Neochentina Spp, Weevils (Curculionidae), During the Re-Inversion Period in the Lake victoria

International Nuclear Information System (INIS)

Ochiel, G.R.S.

2002-01-01

The paper presents recent results from an ongoing classical biological control programme for water hyacinth, implemented by Kenya Agricultural Research Institute Under the Lake Environmental Project. After the successful control of the weed, a re-inversion in the lake was experienced in August 2000 in Nyakach Bay. Between november 2000 and June 2001, approximately 5600 adults Neochetina spp. (coleoptera: Curculionidae) weevils, biological control agents for water hyacinth Eichhornia crassipes (Liliales: Ponteridaceae) were harvested, from the Kibos rearing facility, Namba-Okana 'field security' and community weevil rearing units. Weevils were released on water hyacinth at thirteen sites in Berkeley, Nyakach, Osodo, Kendu, Homa and Karungu and Muhuru Bays, at Kuja-Migori river tributaries and upstream of Nzoia, Yala and Sondu-Miriu rivers. In general, reproductive and growth potential (number of daughter plants, petiole length and laminar area) and fresh weight of the weed was suppressed. there was a gradual increase in insect population levels (number of weevils plant -1 ) and damage to plants by weevil larvae. there is need to carry out an aerial survey to verify the visual estimates of water hyacinth cover and intensify mass rearing and releases of weevils in hotspot areas and to concentrate releases in riverine systems

Disinfestation of stored rice and corn grains by gamma irradiation. 3. Survival values for irradiated rice weevil and flour beetle and comparison of gamma irradiation and fumigation of weevil infested grains

International Nuclear Information System (INIS)

Manoto, E.C.; Villarcarlos, L.T.

1976-02-01

Survival values for Sitophilus oryzae and Tribolium castaneum adults were studied using gamma radiation dosage of 25, 50, 100 and 150 krad. Results with the two species seemed similar, although the rice weevil appeared the more sensitive. Rice and corn grains were artificially infested with Sitophilus oryzae and then treated with gamma radiation or fumigation. Both treatment reduced or eliminated adult emergence although fumigation left some insecticidal residues in corn. Sterility in the adult weevils was induced by 15 or 25 krad treatment of gamma radiation. A practical control level for bulk irradiation of rice or corn grains could probably be achieved by a 25 krad treatment although complete disinfestation should be achieved by a 50 krad treatment

Evaluation of the Weevil-damaged Sweet Potato as Substrate for Microbial Protein Obtaining

Directory of Open Access Journals (Sweden)

Lic. Antonio Montes-de-Oca-Olivares

2015-11-01

Full Text Available The production of microbial protein from agricultural and agroindustrial wastes is an important way to supply the demand of this essential nutritional principle. Sweet potato (Ipomea batata tubercles damaged by weevil (Cylas formicarius are considered a waste due to their unpleasant flavor. This research deal in the characterization of sweet potato damaged by weevil, as an alternative substratefor the culture of the fodder yeast Candida utilis. It was found that the damaged tubercle had a similar composition that the healthy one, concerning dry matter, total reducing sugars, nitrogen and minerals; the high content of reducing sugars (30-40 % dry weight recommends the use of this waste as a substrate for single cell protein production. Several fungal strains were assayed to enzymatic degradation of sweet potato polysaccharides; from these ones, Aspergillus oryzae H/28-1 and Neurospora sp. were the more actives to release reducing sugars to the culture medium, being the last one the more prominent. Theyeast Candida utilis showed a satisfactory growth in media formulated in basis to weevil-damaged sweet potato, reaching reducing sugar consumptions over 80 % and biomass yields of 37-58 %; addition of urea as nitrogen source improved both parameters of the growth. The fermentation’s end-product acquired a pleasant flavor, which suggests a better palatability.

Dataset on the regulation of banana weevil abundance and corm damage associated with plant richness and the ground-dwelling arthropods’ food web

Directory of Open Access Journals (Sweden)

Charlotte Poeydebat

2017-12-01

Full Text Available The data presented in this article are related to the research article entitled ̎Plant richness enhances banana weevil regulation in a tropical agroecosystem by affecting a multitrophic food web ̎ [1]. It provides information about plant species richness, weevil corm damage and the abundance of different arthropod groups, including the banana weevil and its potential natural enemies and alternative preys.

Relationships of abscised cotton fruit to boll weevil (Coleoptera: Curculionidae) feeding, oviposition, and development.

Science.gov (United States)

Showler, Allan T

2008-02-01

Abscised cotton, Gossypium hirsutum L., fruit in field plots planted at different times were examined to assess adult boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), use of squares and bolls during 2002 and 2003 in the Lower Rio Grande Valley of Texas. Although boll abscission is not necessarily related to infestation, generally more bolls abscised than squares and abundances of fallen bolls were not related to the planting date treatments. During 2003, fallen squares were most abundant in the late-planted treatment. Although large squares (5.5-8-mm-diameter) on the plant are preferred for boll weevil oviposition, diameter of abscised squares is not a reliable measurement because of shrinkage resulting from desiccation and larval feeding. Fallen feeding-punctured squares and bolls were most abundant in late plantings but differences between fallen feeding-punctured squares versus fallen feeding-punctured bolls were found in only one treatment in 2003. During the same year, fallen oviposition-punctured squares were more numerous in the late-planted treatment than in the earlier treatments. Treatment effects were not found on numbers of oviposition-punctured bolls, but fallen oviposition-punctured squares were more common than bolls in the late-planted treatment compared with earlier treatments each year. Dead weevil eggs, larvae, and pupae inside fallen fruit were few and planting date treatment effects were not detected. Living third instars and pupae were more abundant in fallen squares of the late-planted treatment than in the earlier treatments and bolls of all three treatments. This study shows that fallen squares in late-planted cotton contribute more to adult boll weevil populations than bolls, or squares of earlier plantings.

EVALUATION OF NATURAL ENEMIES IN CONTROLLING OF THE BANANA WEEVIL BORER Cosmopolites sordidus Germar IN WEST SUMATRA

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Ahsol Hasyim

2016-10-01

Full Text Available The banana weevil, Cosmopolites sordidus Germar, is an important pest of highland banana and plantain in Africa, but it exists in low densities in presumed area of origin in Southeast Asia such as in Indonesia. This suggests a possible existence of effective co-evolved natural enemies in the origin area of Indonesia, especially West Sumatra. The objectives of this study were: (1 to evaluate banana weevil pest status at selected sites in West Sumatra, (2 to survey parasitoids and predators, and (3 to determine the control potential of the most important natural enemies. Surveys were undertaken in March 2002-August 2003 in five locations in West Sumatra, i.e., Bukittinggi, Sitiung, Pariaman, Pasaman, and Batusangkar. Five farms per site were selected randomly among all farms that contained banana stands of > 0.5 ha. Sampling for banana weevil adults and damage, and for predators was done throughout small banana stands and within a 20 m x 40 m (0.08 ha subplot on larger farms. Field-collected larvae were taken to the laboratory and reared on corm pieces (3 cm x 3 cm x 3 cm until pupation. Larvae were collected from pseudostem as well as corm residues. To estimate the abundance of non-social predators, i.e., those other than ants, 10 residues each on each farm were examined from plants that had been harvested 1-4 weeks, 5-8 weeks or 9 or more weeks before our visit to the site. Samples of the different morphospecies were saved in alcohol for later identification. The result showed that the banana weevil incidence was found to be low,  0.6-1.7 adults per trap. Plant damage indices were below 2.2%. We collected and reared 24,360 eggs and 3118 larvae, but no parasitism was detected. Phorids (Megaselia sp. and drosophilids were recovered from larval rearings, but most likely were scavengers. A complex of predators was detected, the most important of which was the histerid beetles,  Plaesius javanus Erichson. In laboratory tests, adults and larvae

Cool-season annual pastures with clovers to supplement wintering beef cows nursing calves

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Gunter Stacey A

2012-07-01

Full Text Available Abstract In December of 3 years, 87 beef cows with nursing calves (594 ± 9.8 kg; calving season, September to November at side were stratified by body condition score, body weight, cow age, and calf gender and divided randomly into 6 groups assigned to 1 of 6 cool-season annual pastures (0.45 ha/cow that had been interseeded into a dormant common bermudagrass (Cynodon dactylon [L.] Pers./bahiagrass (Paspalum notatum Flugge sod. Pastures contained 1 of the following 3 seeding mixtures (2 pastures/mixture: 1 wheat (Triticum aestivum L. and ryegrass (Lolium multiflorum Lam., WRG, 2 wheat and ryegrass plus red clover (Trifolium pretense L., WRR, or 3 wheat and ryegrass plus white (Trifolium repens L. and crimson clovers (Trifolium incarnatum L., WRW. All groups had ad libitum access to grass hay (12% crude protein; 58% total digestible nutrients. The second week in December, cow estrous cycles were synchronized and artificially inseminated. In late December, a bull was placed with each group for 60-d. Data were analyzed with an analysis of variance using a mixed model containing treatment as the fixed effect and year as the random effect. Body weight and condition scores did not differ (P ≥ 0.27 among cows between February and June. Calf birth weights or average daily gain did not differ (P ≥ 0.17 among treatments; however, calves grazing pastures with clovers did tend (P = 0.06 to weigh more than calves grazing grass only. Weaning weight per cow exposed to a bull was greater (P = 0.02 for WRR and WRW than WRG. Cows grazing winter-annual pastures containing clovers tended to wean more calf body weight per cow exposed to a bull than cows grazing the grass only pastures.

Inhibitory potential of pure isoflavonoids, red clover, and alfalfa extracts on hemoglobin glycosylation

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Mohsen Hosseini

2015-03-01

Full Text Available BACKGROUND: Non-enzymatic glycosylation of hemoglobin is complications of diabetes. Antioxidant system imbalance can result in the emergence of free radicals’ destructive effects in the long-term. Red clover (Trifolium pratense L. and alfalfa (Medicago sativa L. contain isoflavonoids and have antioxidant activity. This experimental study evaluated the inhibitory activity of pure isoflavonoids (daidzein and genistein, red clover and alfalfa extracts on hemoglobin glycosylation. METHODS: This study was performed in Iran. Stock solution of hydroalcoholic extracts of red clover and alfalfa in concentrations of 1 and 10 g/100 ml and stock solution of daidzein and genistein in concentrations of 250 ng, 500 ng, 25 µg and 250 µg/100 ml were prepared as case groups. Control group was without hydroalcoholic extracts of plants and pure isoflavonoids. All experiments were performed in triplicate. Hemoglobin was prepared and antioxidant activities were investigated to estimate degree of nonenzymatic hemoglobin glycosylation. RESULTS: There was no significantly difference between used extracts (extract of red clover and alfalfa and control of the hemoglobin glycosylation but using daidzein (P = 0.046, 0.029 and 0.021, respectively and genistein (P = 0.034, 0.036 and 0.028 significantly inhibited (P < 0.050 this reaction in 25 µg/100 ml, 250 and 500 ng/100 ml concentrations when compared to control. in 25 µg/100 ml, 250 ng and 500 ng/100 ml concentrations percentage of inhibition were 32, 80 and 74.5% respectively with used of daidzein and were 21, 83 and 76% respectively with consumption of genistein. CONCLUSION: According to decrease of glycation of hemoglobin with isoflavonoids, two used plant in this study containing isoflavonoid may be useful on diabetes.   

Attractant compositions for weevils of the genus Otiorhynchus and uses thereof

NARCIS (Netherlands)

Bruck, D.J.; Tol, van R.W.H.M.; Griepink, F.C.

2011-01-01

The present invention relates to formulations of volatile organic compounds having effects on Otiorhynchus weevils e.g., Otiorhynchus sulcatus. In some embodiments, volatile organic compounds selected from (E)-2-hexenol, (Z)-2-pentenol, methyl eugenol and a combination thereof are effective for

Enchytraeids as indicator of soil quality in temporary organic grass-clover leys under contrasting management

DEFF Research Database (Denmark)

Maraldo, Kristine; Schmelz, Rüdiger; Larsen, Thomas

2015-01-01

One objective in organic farming is to sustain the quality of the soil resource. Because enchytraeids are an important soil faunal component, they stand as bioindicators of soil quality. We tested this candidature in a field experiment on loamy sand soil with 1- and 4-year old grass-clover leys...... interactions among soil physical, chemical and biological properties suggest that enchytraeid abundance is not a feasible stand-alone indicator of management impacts on soil quality in temporary grass-clover leys but may candidate as one of several biological key parameters in more comprehensive soil quality...

Field evaluation of Bt cotton crop impact on nontarget pests: cotton aphid and boll weevil.

Science.gov (United States)

Sujii, E R; Togni, P H B; de A Ribeiro, P; de A Bernardes, T; Milane, P V G N; Paula, D P; Pires, C S S; Fontes, E M G

2013-02-01

Bt cotton plants expressing Cry1Ac protein have high specificity for the control of lepidopteran larvae. However, studies conducted in several countries have shown these plants have a differential impact on nontarget herbivores. The aim of this study was to compare the colonization rates and population abundance of the cotton aphid, Aphis gossypii Glover (Hemiptera: Aphididae) and the boll weevil, Anthonomus grandis Boheman (Coleoptera: Curculionidae), in plots of Bt (Nuopal) and non-Bt cotton (Delta Opal) in an experimental field in Brasilia, DF, Brazil. No difference was observed in the preference and colonization by winged aphids to plants from the two treatments. There was no significant difference in abundance of wingless aphids or in the production of winged aphids between treatments. Apparently, the parameters that control factors such as fecundity, survival, and dispersal were similar on both Bt and non-Bt plants. Monitoring of plants for coccinellids, a specialist predator of aphids, and ants that act on the dispersal of aphids among plants showed no significant difference between Bt and non-Bt plants, supporting the inference above. Regarding the effect on boll weevil, there was also no significant difference between treatments in the total number of fruiting structures attacked in each plot, the percentage of fruiting structures attacked per plant or on the number of weevils emerging from fruits with boll weevil damage from egg-laying, when damaged fruit samples were held in the laboratory. Based on these results, we conclude that there is no impact of Bt cotton crop expressing Cry1Ac on the nontarget herbivores tested under field conditions.

Effects of combining microbial and chemical insecticides on mortality of the Pecan Weevil (Coleoptera: Curculionidae).

Science.gov (United States)

Shapiro-Ilan, David I; Cottrell, Ted E; Wood, Bruce W

2011-02-01

The pecan weevil, Curculio caryae (Horn), is a key pest of pecan [Carya illinoinensis (Wangenh.) K. Koch]. Current control recommendations are based on chemical insecticide applications. Microbial control agents such as the entomopathogenic nematode, Steinernema carpocapsae (Weiser) and the fungus Beauveria bassiana (Balsamo) Vuillemin occur naturally in southeastern U.S. pecan orchards and have shown promise as alternative control agents for C. caryjae. Conceivably, the chemical and microbial agents occur simultaneously within pecan orchards or might be applied concurrently. The objective of this study was to determine the interactions between two chemical insecticides that are used in commercial C. caryae control (i.e., carbaryl and cypermethrin applied below field rates) and the microbial agents B. bassiana and S. carpocapsae. In laboratory experiments, pecan weevil larval or adult mortality was assessed after application of microbial or chemical treatments applied singly or in combination (microbial + chemical agent). The nature of interactions (antagonism, additivity, or synergy) in terms of weevil mortality was evaluated over 9 d (larvae) or 5 d (adults). Results for B. bassiana indicated synergistic activity with carbaryl and antagonism with cypermethrin in C. caryae larvae and adults. For S. carpocapsae, synergy was detected with both chemicals in C. caryae larvae, but only additive effects were detected in adult weevils. Our results indicate that the chemical-microbial combinations tested are compatible with the exception of B. bassiana and cypermethrin. In addition, combinations that exhibited synergistic interactions may provide enhanced C. caryae control in commercial field applications; thus, their potential merits further exploration.

Continued pheromone release by boll weevils (Coleoptera: curculionidae) following host removal

Science.gov (United States)

Pheromone traps are a key component of management and eradication programs directed against the boll weevil, Anthonomus grandis (Boheman), but trap data remain difficult to interpret because of the day-to-day variability in captures. Our prior observations suggested a substantial proportion of boll...

White clover fractions as protein source for monogastrics: dry matter digestibility and protein digestibility-corrected amino acid scores.

Science.gov (United States)

Stødkilde, Lene; Damborg, Vinni K; Jørgensen, Henry; Laerke, Helle N; Jensen, Søren K

2018-05-01

The present study aimed to evaluate the use of white clover as an alternative protein source for monogastrics. White clover plant and leaves were processed using a screw-press resulting in a solid pulp and a juice from which protein was acid-precipitated. The chemical composition of all fractions was determined and digestibility of dry matter (DM) and protein was assessed in an experiment with growing rats. Protein concentrates were produced with crude protein (CP) contents of 451 g kg -1 and 530 g kg -1 DM for white clover plant and leaves, respectively, and a pulp with CP contents of 313 and 374 g kg -1 DM from plant and leaves, respectively. The amino acid composition ranged from 4.72 to 6.49 g per 16 g of nitrogen (N) for lysine, 1.82-2.6 g per 16 g N for methionine and cysteine, and 3.66-5.24 g per 16 g N for threonine. True faecal digestibility of protein varied from 0.81 to 0.88, whereas DM digestibility was in the range 0.72-0.80. Methionine and cysteine were found to be limiting in all fractions, regardless of the reference group used. A high digestibility of white clover protein was found irrespective of the physical fractionation. Together with a well-balanced amino acid composition, this makes white clover a promising protein source for monogastrics. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Oleoresin crystallization in eastern white pine: relationships with chemical components of cortical oleoresin and resistance to the white-pine weevil

Science.gov (United States)

Ronald C. Wilkinson

1979-01-01

Natural and weevil-larva-induced crystallization of oleoresin from 45 eastern white pine trees with known resin acid and monoterpene composition, and from 59 pairs of nonweeviled and heavily weeviled trees from the same seed sources, was examined in mid- and late spring. Very little difference was found between larva-induced and natural crystallization. Strobic acid-...

Control of Pecan Weevil With Microbial Biopesticides.

Science.gov (United States)

Shapiro-Ilan, David I; Cottrell, Ted E; Bock, Clive; Mai, Kim; Boykin, Debbie; Wells, Lenny; Hudson, William G; Mizell, Russell F

2017-12-08

The pecan weevil, Curculio caryae (Horn) (Coleoptera: Curculionidae), is a key pest of pecans Carya illinoinensis ([Wangenh.] K. Koch) (Fagales: Juglandaceae). Control recommendations rely on broad spectrum chemical insecticides. Due to regulatory and environmental concerns, effective alternatives for C. caryae control must be sought for pecan production in conventional and organic systems. We explored the use of microbial biopesticides for control of C. caryae in Georgia pecan orchards. Three experiments were conducted. The first investigated an integrated microbial control approach in an organic system at two locations. Three microbial agents, Grandevo (based on byproducts of the bacterium Chromobacterium subtsugae Martin, Gundersen-Rindal, Blackburn & Buyer), the entomopathogenic nematode Steinernema carpocapsae (Weiser), and entomopathogenic fungus Beauveria bassiana (Balsamo) Vuillemin, were applied to each treatment plot (0.6 ha) at different times during the season. A second experiment compared the effects of S. carpocapsae and B. bassiana applied as single treatments relative to application of both agents (at different times); survival of C. caryae was assessed approximately 11 mo after larvae were added to pots sunk in an organic pecan orchard. In a conventional orchard (with 1.0 ha plots), the third experiment compared Grandevo applications to a commonly used regime of chemical insecticides (carbaryl alternated with a pyrethroid). All experiments were repeated in consecutive years. The combined pest management tactic (experiment 1) reduced C. caryae infestation relative to non-treated control plots in both locations in 2014 and one of the two locations in 2015 (the other location had less than 1% infestation). In experiment 2, no differences among combined microbial treatments, single-applied microbial treatments or different numbers of application were observed, yet all microbial treatments reduced C. caryae survival relative to the control. In the third

Stable integration and expression of a cry1Ia gene conferring resistance to fall armyworm and boll weevil in cotton plants.

Science.gov (United States)

Silva, Carliane Rc; Monnerat, Rose; Lima, Liziane M; Martins, Érica S; Melo Filho, Péricles A; Pinheiro, Morganna Pn; Santos, Roseane C

2016-08-01

Boll weevil is a serious pest of cotton crop. Effective control involves applications of chemical insecticides, increasing the cost of production and environmental pollution. The current genetically modified Bt crops have allowed great benefits to farmers but show activity limited to lepidopteran pests. This work reports on procedures adopted for integration and expression of a cry transgene conferring resistance to boll weevil and fall armyworm by using molecular tools. Four Brazilian cotton cultivars were microinjected with a minimal linear cassette generating 1248 putative lines. Complete gene integration was found in only one line (T0-34) containing one copy of cry1Ia detected by Southern blot. Protein was expressed in high concentration at 45 days after emergence (dae), decreasing by approximately 50% at 90 dae. Toxicity of the cry protein was demonstrated in feeding bioassays revealing 56.7% mortality to boll weevil fed buds and 88.1% mortality to fall armyworm fed leaves. A binding of cry1Ia antibody was found in the midgut of boll weevils fed on T0-34 buds in an immunodetection assay. The gene introduced into plants confers resistance to boll weevil and fall armyworm. Transmission of the transgene occurred normally to T1 progeny. All plants showed phenotypically normal growth, with fertile flowers and abundant seeds. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Use of some inorganic and organic compounds as decontaminants for cobalt-60 and caesium-134 by clover plant grown on Inshas sandy soil

Energy Technology Data Exchange (ETDEWEB)

Abdel Sabour, M.F.; El-Naggar, H.A.; Soliman, S.M. (Atomic Energy Establishment, Cairo (Egypt). Nuclear Chemistry Dept.)

1991-01-01

Outdoor lysimeter experiments were carried out to elucidate the effect of 4 inorganic and 3 organic salts on {sup 60}Co and {sup 134}Cs uptake and dry matter yield of three cuts of clover in the soils of Inshas. A new concept was proposed for assessing the difference in capacity of soil to supply radionuclides to plants as affected by applied inorganic or organic compounds. A relation of plant tissue radionuclide content with time can be expressed in an exponential equation with corresponding regression coefficients. When the same plant species is grown on the same soil differing only in the applied compounds (e.g. Fe-EDDHA, Fe-DTPA, Fe-OAC, Fe(COO){sub 2}, Al(OH){sub 3}, Ca(H{sub 2}PO{sub 4}){sub 2}, Fe{sub 2}O{sub 3}) the derived equation will change. Differences of either Co or Cs accumulation with time between control and any other treatment were evaluated. The data also show that Fe-DTPA is preferred for {sup 60}Co as enhancing compound for plant uptake (for decontamination use), compared with other applied salts, on the other hand, any tested salts did not significantly effect {sup 134}Cs taken by clover. It was also found that more than 70% of the total cobalt uptake was accumulated in the roots which indicate that Co is less mobile in plants than Cs. (orig.).

Use of some inorganic and organic compounds as decontaminants for cobalt-60 and caesium-134 by clover plant grown on Inshas sandy soil

International Nuclear Information System (INIS)

Abdel Sabour, M.F.; El-Naggar, H.A.; Soliman, S.M.

1991-01-01

Outdoor lysimeter experiments were carried out to elucidate the effect of 4 inorganic and 3 organic salts on 60 Co and 134 Cs uptake and dry matter yield of three cuts of clover in the soils of Inshas. A new concept was proposed for assessing the difference in capacity of soil to supply radionuclides to plants as affected by applied inorganic or organic compounds. A relation of plant tissue radionuclide content with time can be expressed in an exponential equation with corresponding regression coefficients. When the same plant species is grown on the same soil differing only in the applied compounds (e.g. Fe-EDDHA, Fe-DTPA, Fe-OAC, Fe(COO) 2 , Al(OH) 3 , Ca(H 2 PO 4 ) 2 , Fe 2 O 3 ) the derived equation will change. Differences of either Co or Cs accumulation with time between control and any other treatment were evaluated. The data also show that Fe-DTPA is preferred for 60 Co as enhancing compound for plant uptake (for decontamination use), compared with other applied salts, on the other hand, any tested salts did not significantly effect 134 Cs taken by clover. It was also found that more than 70% of the total cobalt uptake was accumulated in the roots which indicate that Co is less mobile in plants than Cs. (orig.) [de

Factors influencing pheromone trap effectiveness in attracting the banana weevil, Cosmopolites sordidus

NARCIS (Netherlands)

Tinzaara, W.; Gold, C.S.; Dicke, M.; Huis, van A.; Ragama, P.E.

2005-01-01

Studies were conducted in Uganda to evaluate the influence of distance, environmental factors, trap location and trap type on catches of Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae) in pheromone-baited traps. Marked weevils were released at recorded locations within plots. Trap

Genetic variations between two ecotypes of Egyptian clover by inter ...

African Journals Online (AJOL)

Aghomotsegin

2015-06-10

Jun 10, 2015 ... Four Egyptian clover (Trifolium alexandrinum L) cultivars representing two ecotypes were used in the present study. Fahl cultivar is prevalent in whole Egypt and is good for single cut as it has poor regeneration ability, whereas Serw1, Giza6 and Gemmiza1 give 5-6 cuts of good fodder. Techniques based ...

Relationship between nitrogen cycling and nitrous oxide emission in grass-clover pasture

OpenAIRE

Ambus, P.

2005-01-01

The paper reports on a work assessing the relationship between gross N transformations in grass-clover soils and emissions of nitrous oxide. By this manner, the source strength of the biogenic processes responsible for nitrous oxide production is evaluated.

Deleterious effects of plant cystatins against the banana weevil Cosmopolites sordidus.

Science.gov (United States)

Kiggundu, Andrew; Muchwezi, Josephine; Van der Vyver, Christell; Viljoen, Altus; Vorster, Juan; Schlüter, Urte; Kunert, Karl; Michaud, Dominique

2010-02-01

The general potential of plant cystatins for the development of insect-resistant transgenic plants still remains to be established given the natural ability of several insects to compensate for the loss of digestive cysteine protease activities. Here we assessed the potential of cystatins for the development of banana lines resistant to the banana weevil Cosmopolites sordidus, a major pest of banana and plantain in Africa. Protease inhibitory assays were conducted with protein and methylcoumarin (MCA) peptide substrates to measure the inhibitory efficiency of different cystatins in vitro, followed by a diet assay with cystatin-infiltrated banana stem disks to monitor the impact of two plant cystatins, oryzacystatin I (OC-I, or OsCYS1) and papaya cystatin (CpCYS1), on the overall growth rate of weevil larvae. As observed earlier for other Coleoptera, banana weevils produce a variety of proteases for dietary protein digestion, including in particular Z-Phe-Arg-MCA-hydrolyzing (cathepsin L-like) and Z-Arg-Arg-MCA-hydrolyzing (cathepsin B-like) proteases active in mildly acidic conditions. Both enzyme populations were sensitive to the cysteine protease inhibitor E-64 and to different plant cystatins including OsCYS1. In line with the broad inhibitory effects of cystatins, OsCYS1 and CpCYS1 caused an important growth delay in young larvae developing for 10 days in cystatin-infiltrated banana stem disks. These promising results, which illustrate the susceptibility of C. sordidus to plant cystatins, are discussed in the light of recent hypotheses suggesting a key role for cathepsin B-like enzymes as a determinant for resistance or susceptibility to plant cystatins in Coleoptera. 2009 Wiley Periodicals, Inc.

Phenotypic and genetic characterization of wildland collections of western and Searls prairie clovers for rangeland revegetation in the western USA

Science.gov (United States)

Kishor Bhattarai

2010-01-01

Western prairie clover [Dalea ornata (Douglas ex Hook.) Eaton & J. Wright] is a perennial legume that occurs in the northern Great Basin, Snake River Basin, and southern Columbia Plateau, whereas Searls prairie clover [Dalea searlsiae (A. Gray) Barneby], also a perennial legume, occurs in the southern Great Basin and surrounding areas. Understanding the genetic and...

The effects of island forest restoration on open habitat specialists: the endangered weevil Hadramphus spinipennis Broun and its host-plant Aciphylla dieffenbachii Kirk

Directory of Open Access Journals (Sweden)

Emily D. Fountain

2015-02-01

Full Text Available Human alteration of islands has made restoration a key part of conservation management. As islands are restored to their original state, species interactions change and some populations may be impacted. In this study we examine the coxella weevil, (Hadramphus spinipennis Broun and its host-plant Dieffenbach’s speargrass (Aciphylla dieffenbachii Kirk, which are both open habitat specialists with populations on Mangere and Rangatira Islands, Chathams, New Zealand. Both of these islands were heavily impacted by the introduction of livestock; the majority of the forest was removed and the weevil populations declined due to the palatability of their host-plant to livestock. An intensive reforestation program was established on both islands over 50 years ago but the potential impacts of this restoration project on the already endangered H. spinipennis are poorly understood. We combined genetic and population data from 1995 and 2010–2011 to determine the health and status of these species on both islands. There was some genetic variation between the weevil populations on each island but little variation within the species as a whole. The interactions between the weevil and its host-plant populations appear to remain intact on Mangere, despite forest regeneration. A decline in weevils and host-plant on Rangatira does not appear to be caused by canopy regrowth. We recommend that (1 these populations be monitored for ongoing effects of long-term reforestation, (2 the cause of the decline on Rangatira be investigated, and (3 the two populations of weevils be conserved as separate evolutionarily significant units.

Influence of arbuscular mycorrhizae on biomass production and nitrogen fixation of berseem clover plants subjected to water stress.

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Sergio Saia

Full Text Available Several studies, performed mainly in pots, have shown that arbuscular mycorrhizal symbiosis can mitigate the negative effects of water stress on plant growth. No information is available about the effects of arbuscular mycorrhizal symbiosis on berseem clover growth and nitrogen (N fixation under conditions of water shortage. A field experiment was conducted in a hilly area of inner Sicily, Italy, to determine whether symbiosis with AM fungi can mitigate the detrimental effects of drought stress (which in the Mediterranean often occurs during the late period of the growing season on forage yield and symbiotic N2 fixation of berseem clover. Soil was either left under water stress (i.e., rain-fed conditions or the crop was well-watered. Mycorrhization treatments consisted of inoculation of berseem clover seeds with arbuscular mycorrhizal spores or suppression of arbuscular mycorrhizal symbiosis by means of fungicide treatments. Nitrogen biological fixation was assessed using the 15N-isotope dilution technique. Arbuscular mycorrhizal symbiosis was able to mitigate the negative effect of water stress on berseem clover grown in a typical semiarid Mediterranean environment. In fact, under water stress conditions, arbuscular mycorrhizal symbiosis resulted in increases in total biomass, N content, and N fixation, whereas no effect of crop mycorrhization was observed in the well-watered treatment.

Influence of arbuscular mycorrhizae on biomass production and nitrogen fixation of berseem clover plants subjected to water stress.

Science.gov (United States)

Saia, Sergio; Amato, Gaetano; Frenda, Alfonso Salvatore; Giambalvo, Dario; Ruisi, Paolo

2014-01-01

Several studies, performed mainly in pots, have shown that arbuscular mycorrhizal symbiosis can mitigate the negative effects of water stress on plant growth. No information is available about the effects of arbuscular mycorrhizal symbiosis on berseem clover growth and nitrogen (N) fixation under conditions of water shortage. A field experiment was conducted in a hilly area of inner Sicily, Italy, to determine whether symbiosis with AM fungi can mitigate the detrimental effects of drought stress (which in the Mediterranean often occurs during the late period of the growing season) on forage yield and symbiotic N2 fixation of berseem clover. Soil was either left under water stress (i.e., rain-fed conditions) or the crop was well-watered. Mycorrhization treatments consisted of inoculation of berseem clover seeds with arbuscular mycorrhizal spores or suppression of arbuscular mycorrhizal symbiosis by means of fungicide treatments. Nitrogen biological fixation was assessed using the 15N-isotope dilution technique. Arbuscular mycorrhizal symbiosis was able to mitigate the negative effect of water stress on berseem clover grown in a typical semiarid Mediterranean environment. In fact, under water stress conditions, arbuscular mycorrhizal symbiosis resulted in increases in total biomass, N content, and N fixation, whereas no effect of crop mycorrhization was observed in the well-watered treatment.

Assessment of Protective Effect of Some Modern Agrochemicals against Ozone-Induced Stress in Sensitive Clover and Tobacco Cultivars

OpenAIRE

Blum, Oleg; Didyk, Nataliya; Pavluchenko, Nataliya; Godzik, Barbara

2011-01-01

Some modern agrochemicals with antioxidant potential were tested for their protective effect against ozone injury using clover and tobacco ozone-sensitive cultivars as model plants subjected to ambient ozone at two sites (Kyiv city in Ukraine and Szarów village in Poland). All used agrochemicals showed partial protective effects against ozone injury on clover and tobacco. Conducted studies confirmed the effectiveness of modern fungicides belonging to strobilurin group as protectants of sensit...

Effects of gamma radiation and irradiated bean seeds on the dry bean weevil, Acanthoscelides obtectus say (Coleoptera: Bruchidae)

International Nuclear Information System (INIS)

Ignatowicz, S.; Brzostek, G.

1988-01-01

Low dosages of gamma radiation affected the development of immature stages of the bean weevil, Acanthoscelides obtectus Say. Radiosensitivity of the bean weevils decreased during their development, and adults seemed to be the most resistant stage for gamma radiation. There were no significant differences in mortality of immature stages of the pest during their development in beans treated with gamma radiation at dosages up to 1.06 kGy. Moreover, the females showed no ovipositional preference for untreated or irradiated beans

Crystallization and preliminary X-ray diffraction analysis of red clover necrotic mosaic virus

International Nuclear Information System (INIS)

Martin, Stanton L.; Guenther, Richard H.; Sit, Tim L.; Swartz, Paul D.; Meilleur, Flora; Lommel, Steven A.; Rose, Robert B.

2010-01-01

Virions of red clover necrotic mosaic virus have been purified and crystallized. The space group was determined to be I23, with unit-cell parameter a = 377.8 Å. The crystals diffracted to 4 Å resolution. Red clover necrotic mosaic virus (RCNMV) is a species that belongs to the Tombusviridae family of plant viruses with a T = 3 icosahedral capsid. RCNMV virions were purified and were crystallized for X-ray analysis using the hanging-drop vapor-diffusion method. Self-rotation functions and systematic absences identified the space group as I23, with two virions in the unit cell. The crystals diffracted to better than 4 Å resolution but were very radiation-sensitive, causing rapid decay of the high-resolution reflections. The data were processed to 6 Å in the analysis presented here

Cumulative effects of white clover residues on the changes in soil ...

African Journals Online (AJOL)

STORAGESEVER

2009-05-18

May 18, 2009 ... The residual effects of white clover on soil properties indicated a significant increase in saturation percentage (17–23%) and .... determined by leaching the soil with KCl followed by extraction of ...... accumulation, and oil quality of French basil. ... of the Final Workshop of the Farming System Integrated Pest.

effect of age, female mating status and density on the banana weevil ...

African Journals Online (AJOL)

journal

Laboratory bioassays were conducted using a double pitfall olfactometer, while a bucket pitfall trap was ... baited trap. The response of the weevils to the pheromone was not significantly (P>0.05) influenced by its previous density. Key Words: Cosmopolites sordidus, mating status, ...... evolutionary ecological perspective.

A fungal endophyte helps plants to tolerate root herbivory through changes in gibberellin and jasmonate signaling.

Science.gov (United States)

Cosme, Marco; Lu, Jing; Erb, Matthias; Stout, Michael Joseph; Franken, Philipp; Wurst, Susanne

2016-08-01

Plant-microbe mutualisms can improve plant defense, but the impact of root endophytes on below-ground herbivore interactions remains unknown. We investigated the effects of the root endophyte Piriformospora indica on interactions between rice (Oryza sativa) plants and its root herbivore rice water weevil (RWW; Lissorhoptrus oryzophilus), and how plant jasmonic acid (JA) and GA regulate this tripartite interaction. Glasshouse experiments with wild-type rice and coi1-18 and Eui1-OX mutants combined with nutrient, jasmonate and gene expression analyses were used to test: whether RWW adult herbivory above ground influences subsequent damage caused by larval herbivory below ground; whether P. indica protects plants against RWW; and whether GA and JA signaling mediate these interactions. The endophyte induced plant tolerance to root herbivory. RWW adults and larvae acted synergistically via JA signaling to reduce root growth, while endophyte-elicited GA biosynthesis suppressed the herbivore-induced JA in roots and recovered plant growth. Our study shows for the first time the impact of a root endophyte on plant defense against below-ground herbivores, adds to growing evidence that induced tolerance may be an important root defense, and implicates GA as a signal component of inducible plant tolerance against biotic stress. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

Weevil x Insecticide: Does 'Personality' Matter?

Science.gov (United States)

Morales, Juliana A; Cardoso, Danúbia G; Della Lucia, Terezinha Maria C; Guedes, Raul Narciso C

2013-01-01

An insect's behavior is the expression of its integrated physiology in response to external and internal stimuli, turning insect behavior into a potential determinant of insecticide exposure. Behavioral traits may therefore influence insecticide efficacy against insects, compromising the validity of standard bioassays of insecticide activity, which are fundamentally based on lethality alone. By extension, insect 'personality' (i.e., an individual's integrated set of behavioral tendencies that is inferred from multiple empirical measures) may also be an important determinant of insecticide exposure and activity. This has yet to be considered because the behavioral studies involving insects and insecticides focus on populations rather than on individuals. Even among studies of animal 'personality', the relative contributions of individual and population variation are usually neglected. Here, we assessed behavioral traits (within the categories: activity, boldness/shyness, and exploration/avoidance) of individuals from 15 populations of the maize weevil (Sitophilus zeamais), an important stored-grain pest with serious problems of insecticide resistance, and correlated the behavioral responses with the activity of the insecticide deltamethrin. This analysis was performed at both the population and individual levels. There was significant variation in weevil 'personality' among individuals and populations, but variation among individuals within populations accounted for most of the observed variation (92.57%). This result emphasizes the importance of individual variation in behavioral and 'personality' studies. When the behavioral traits assessed were correlated with median lethal time (LT50) at the population level and with the survival time under insecticide exposure, activity traits, particularly the distance walked, significantly increased survival time. Therefore, behavioral traits are important components of insecticide efficacy, and individual variation should be

Effect of Light Availability on the Interaction between Maritime Pine and the Pine Weevil: Light Drives Insect Feeding Behavior But Also the Defensive Capabilities of the Host

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Estefanía Suárez-Vidal

2017-08-01

Full Text Available Light is a major environmental factor that may determine the interaction between plants and herbivores in several ways, including top-down effects through changes in herbivore behavior and bottom-up effects mediated by alterations of plant physiology. Here we explored the relative contribution of these two regulation processes to the outcome of the interaction of pine trees with a major forest pest, the pine weevil (Hylobius abietis. We studied to what extent light availability influence insect feeding behavior and/or the ability of pines to produce induced defenses in response to herbivory. For this purpose, 3-year old Pinus pinaster plants from three contrasting populations were subjected to 6 days of experimental herbivory by the pine weevil under two levels of light availability (complete darkness or natural sunlight independently applied to the plant and to the insect in a fully factorial design. Light availability strongly affected the pine weevil feeding behavior. The pine weevil fed more and caused larger feeding scars in darkness than under natural sunlight. Besides, under the more intense levels of weevil damage (i.e., those registered with insects in darkness, light availability also affected the pine’s ability to respond to insect feeding by producing induced resin defenses. These results were consistent across the three studied populations despite they differed in weevil susceptibility and inducibility of defenses. Morocco was the most damaged population and the one that induced more defensive compounds. Overall, results indicate that light availability modulates the outcome of the pine–weevil interactions through both bottom-up and top-down regulation mechanisms.

Between-season attraction of cotton boll weevil, Anthonomus grandis Boh. (Coleoptera: Curculionidae adults by its aggregation pheromone

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Fernandes Wedson Desidério

2001-01-01

Full Text Available The present study was undertaken to investigate the attractiveness of boll weevil adults by its aggregation pheromone under winter field conditions. Two experimental fields were utilized at "Casa Branca", SP, Brazil. For each one, three areas were established near the refuge vegetation, sparated 500 m from each other. Each area was divided in three sub-areas or blocks of 100 m² to receive pheromone applications (2.5 g per block. In addition to the pre-application counting, five additional evaluations were carried out after the pheromone applicaton. Ten randomized sampling points per block were considered in each evaluation process. A. grandis adults responded immediately to the pheromone applications, and were captured for 14 days . The highest level of attractiveness was observed 24 hours after application. The application of the boll weevil aggregation pheromone during winter could increase the predation by natural enemies, due to the increase of prey availability. Chemical control can be recommended 24 hours after pheromone applications in small plots as a between-season strategy for the suppression of boll weevil adults.

Control of the mango weevil with the emphasis on radurisation

International Nuclear Information System (INIS)

Kok, I.B.

1979-01-01

The mango weevil is one of the most important mango insect pests. Although it is of lesser importance in the case of early maturing cultivars, it is of greater significance in late maturing cultivars. In these cultivars most of the insects are in die adult beetle stage at harvesting. The beetles are then inclined to leave the seed and tunnel through the edible portion of the fruit, leaving an unsightly scar on the outside of the fruit. This also serves as a suitable site for secondary fungal development. By spraying the mango trees during the winter, or early spring, the beetle population may be significantly reduced. Orchard sanitation and the destruction of the pips which are usually scattered over the farm, also contributes markedly to the reduction of the beetle population. Radurisation of matured, i.e. marketable fruit, protects it from damage in that it prevents the emergence of the weevil. The most effective dosages ranged from 0,5 to 0,85 kGy. Dosages in excess of 0,85 kGy tended to be phytotoxic to the fruit. It is hoped that this research will lead to commercial radurisation treatments [af

effect of age, female mating status and density on the banana weevil ...

African Journals Online (AJOL)

journal

volatiles and the synthetic pheromone. Entomologia Experimentalis et Applicata. 106:169-175. Tinzaara, W., Tushemereirwe, W. and Kashaija,. I. 2000. Efficiency of pheromones and trap types in the capture of the banana weevil. Cosmopolites sordidus Germar in Uganda. Uganda Journal of Agricultural Sciences. 5:91-97.

Preferential Edge Habitat Colonization by a Specialist Weevil, Rhinoncomimus latipes (Coleoptera: Curculionidae)

Science.gov (United States)

Understanding the behavioral basis of dispersal and colonization is critical in biological control systems, where success of a natural enemy depends in part on its ability to find and move to new host patches. We studied behavior of the specialist weevil Rhinoncomimus latipes Korotyaev, a biological...

Relative infestation of some local and developed chickpea genotypes by cowpea weevil

International Nuclear Information System (INIS)

Moustafa, R.A.K.; Abdelkawy, F.K.

1993-01-01

Six chickpea genotypes, half of them are local varieties (Giza 1, Giza 88 and Giza 2) and the other three were developed either by hybridization or through a mutation breeding programme L 1, L 2 and L 3) were evaluated for resistant to cowpea weevil callosobruchus maculatus (F.). Giza 1, Giza 88, L 1 and L 2 are large seeded type, while Giza 2 and L 3 have small seeds. Results indicated that L 1 was more resistant to cowpea weevil than the other large seeded genotypes. On the other hand, L 3 exhibited much more resistant to this pest than Giza 2. However L 1 and L 3 are characterized by high seed yield/plant and have rounded seeds with smooth cream test a. These traits are desirable for the common consumers in Egypt. This means that L 1 and L 3 as a new chickpea germplasm may be of value for the egyptian farmers planting this crop. 3 tab

The occurrence of fungi on the stem base and roots of spring wheat (Triticum aestivum L. grown in monoculture depending on tillage systems and catch crops

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Piotr Kraska

2012-12-01

Full Text Available The present study was carried out in the period 2006-2008 based on an experiment established in 2005. The study evaluated the effect of conservation and plough tillage as well as of four catch crops on the level of infection by fungal pathogens of the stem base and roots of the spring wheat cultivar ‘Zebra’ grown in monoculture. The species composition of fungi colonizing the stem base and roots of spring wheat was determined. The split-plot design of the experiment set up on rendzina soil included plough tillage and conservation tillage with autumn and spring disking of catch crops. The experiment used four methods for regeneration of the spring wheat monoculture stand using the following: undersown red clover and Westerwolds ryegrass crops as well as lacy phacelia and white mustard stubble crops. Plots without catch crops were the control treatment. Red clover and Westerwolds ryegrass catch crops as well as lacy phacelia and white mustard stubble crops had a significant effect on the decrease in the stem base and root infection index of spring wheat compared to the control without catch crops. The disease indices in the tillage treatments under evaluation did not differ significantly from one another. The stem base and roots of spring wheat were most frequently infected by fungi of the genus Fusarium, with F. culmorum being the dominant pathogen of cereals. Compared to conservation tillage, in plough tillage the pathogenic fungus Bipolaris sorokiniana was not found to occur on the stem base and roots. The Westerwolds ryegrass catch crop promoted the occurrence of F. culmorum, both on the stem base and roots of spring wheat.

Effect of Plant Density on Growth Characteristics and Yield of Summer Savory (Satureja hortensis L. and Persian Clover (Trifolium resupinatum L. Intercropping

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f Hassanzadeh Aval

2012-02-01

Full Text Available Abstract In order to evaluate intercropping of summer savory (Satureja hortensis L. and Persian clover (Trifolium resupinatum L., an experiment was conducted in the Agricultural Research Station of Ferdowsi University of Mashhad in 2004 growing season. Treatments were sole cropping of Persian clover (eight rows, double-row intercropping of Persian clover and summer savory with 27, 40 and 80 plants.m-2 (eight rows and sole cropping of summer savory with 27, 40 and 80 plants m-2 (eight rows. For this purpose a complete randomized block design with 4 replications was used. Shoot and stem percentage of summer savory in sole crop treatments were significantly higher than in intercrop. In sole crop treatments, these parameters decreased by increasing plant density, in contrast to the intercrop. Leaf percentage and leaf and flower to stem ratio of summer savory in sole crop treatments were significantly lower than in intercrop. In sole crop treatments, these parameters were increased by increasing plant density, in contrast to intercrop. Effect of different treatments on essential oil percentage of summer savory was not significant. In sole cropping of Persian clover treatment, dry weight of vegetative organs and stem percentage of Persian clover in the first harvest, was lower than other treatments. By decreasing plant density these parameters were decreased in intercropping. In the second and third harvests a reversed pattern was observed. The highest Area Time Equivalent Ratio was obtained in intercropping of persian clover and summer savory with 27 plants.m-2. Keywords: Intercropping, Plant density, Satureja hortensis, Trifolium resupinatum, Essential oil percentage, Area Time Equivalent Ratio

EFFECT OF PLANT ESSENTIAL OILS ON THE DEVELOPMENT AND FERTILITY OF GRAIN WEEVIL (SITOPHILUS GRANARIUS L.

Directory of Open Access Journals (Sweden)

MARIA WAWRZYNIAK

2010-06-01

Full Text Available There was analyzed the effect of selected essential oils (orange, lemon, vanilla, linden blossom, thyme, geranium and tea oils on the development and fertility of the most dangerous cereal grain storage pest, grain weevil. Based on the results obtained, it was observed that a strong effect limiting the population of grain weevil was found for vanilla and orange oils. In the experiment combinations which involved essential oils, there was observed a prolonged pest development cycle and a higher mortality of maternal individuals than in the other tests. On the other hand, the lowest fecundity rate was recorded in the combination in which thyme oil was tested.

Induced Jasmonate Signaling Leads to Contrasting Effects on Root Damage and Herbivore Performance1

Science.gov (United States)

Lu, Jing; Robert, Christelle Aurélie Maud; Riemann, Michael; Cosme, Marco; Mène-Saffrané, Laurent; Massana, Josep; Stout, Michael Joseph; Lou, Yonggen; Gershenzon, Jonathan; Erb, Matthias

2015-01-01

Induced defenses play a key role in plant resistance against leaf feeders. However, very little is known about the signals that are involved in defending plants against root feeders and how they are influenced by abiotic factors. We investigated these aspects for the interaction between rice (Oryza sativa) and two root-feeding insects: the generalist cucumber beetle (Diabrotica balteata) and the more specialized rice water weevil (Lissorhoptrus oryzophilus). Rice plants responded to root attack by increasing the production of jasmonic acid (JA) and abscisic acid, whereas in contrast to in herbivore-attacked leaves, salicylic acid and ethylene levels remained unchanged. The JA response was decoupled from flooding and remained constant over different soil moisture levels. Exogenous application of methyl JA to the roots markedly decreased the performance of both root herbivores, whereas abscisic acid and the ethylene precursor 1-aminocyclopropane-1-carboxylic acid did not have any effect. JA-deficient antisense 13-lipoxygenase (asLOX) and mutant allene oxide cyclase hebiba plants lost more root biomass under attack from both root herbivores. Surprisingly, herbivore weight gain was decreased markedly in asLOX but not hebiba mutant plants, despite the higher root biomass removal. This effect was correlated with a herbivore-induced reduction of sucrose pools in asLOX roots. Taken together, our experiments show that jasmonates are induced signals that protect rice roots from herbivores under varying abiotic conditions and that boosting jasmonate responses can strongly enhance rice resistance against root pests. Furthermore, we show that a rice 13-lipoxygenase regulates root primary metabolites and specifically improves root herbivore growth. PMID:25627217

Reproductive Plasticity of an Invasive Insect Pest, Rice Water Weevil (Coleoptera: Curculionidae).

Science.gov (United States)

Huang, Yunshang; Ao, Yan; Jiang, Mingxing

2017-12-05

Reproductive plasticity is a key determinant of species invasiveness. However, there are a limited number of studies addressing this issue in exotic insects. The rice water weevil Lissorhoptrus oryzophilus Kuschel (Coleoptera: Curculionidae), which is native to North America, is one of the most invasive insect pests in east Asia. In this study, we investigated the reproductive status of first-generation females (progeny of overwintered weevils) from five geographic regions in southern and northern China in the field, and reproductive status and ovipositional features of females provided with suitable host plants in the laboratory after collection. Under field conditions, a proportion of females oviposited, while the rest remained in diapause from all three southern regions investigated, but reproductive development did not take place in females from the two northern regions, where the weevil produces only one generation per year. However, when fed host plants in the laboratory, females from all regions laid eggs. They typically had a very short ovipositional period (3-6 d on average on rice at a temperature of 27°C), laid a low number of eggs, and did not die soon after oviposition; this was different from common reproductive females. We concluded that first-generation L. oryzophilus females, which largely enter diapause after emergence, are highly plastic in their reproductive performance and are ready to reproduce under favorable conditions. Our results indicate the significance of their reproductive plasticity for geographic spread and population development. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Olfactory antennal responses of the black vine weevil (Otiorhynchus sulcatus) to plant volatiles

NARCIS (Netherlands)

Tol, van R.W.H.M.; Visser, J.H.

2002-01-01

Electroantennograms (EAGs) were recorded from the vine weevil, Otiorhynchus sulcatus F. (Coleoptera: Curculionidae) to a broad range of volatile plant compounds. The response profile is restricted to a small number of volatiles that evoke substantial EAGs. Large EAG responses were particularly found

Analysis of the soil food web structure under grass and grass clover

NARCIS (Netherlands)

Eekeren, van N.J.M.; Smeding, F.W.; Vries, de F.T.; Bloem, J.

2006-01-01

The below ground biodiversity of soil organisms plays an important role in the functioning of the the soil ecosystem, and consequently the above ground plant production. The objective of this study is to investigate the effect of grass or grass-clover in combination with fertilisation on the soil

Effects of titanium dioxide nanoparticles on red clover and its rhizobial symbiont

NARCIS (Netherlands)

Moll, Janine; Okupnik, Annette; Gogos, Alexander; Knauer, Katja; Bucheli, Thomas D.; Van Der Heijden, Marcel G A; Widmer, Franco

2016-01-01

Titanium dioxide nanoparticles (TiO2 NPs) are in consideration to be used in plant protection products. Before these products can be placed on the market, ecotoxicological tests have to be performed. In this study, the nitrogen fixing bacterium Rhizobium trifolii and red clover were exposed to two

Molecular and morphological tools to distinguish Scyphophorus acupunctatus Gyllenhal, 1838: a new weevil pest of the endangered Eggers Agave from St Croix, US Virgin Islands

Science.gov (United States)

The Agave Snout Weevil (ASW) or Sisal Weevil, Scyphophorus acupunctatus Gyllenhal, is one of the most destructive pests of agave plants, capable of destroying up to 70% of commercial crops, costing millions of dollars in damage to global industries including tequila, mezcal, perfume, henequen, nardo...

Characterisation of a compton suppressed clover detector for high energy gamma rays (5 MeV ≤ E ≤ 11 MeV)

International Nuclear Information System (INIS)

Saha Sarkar, M.; Kshetri, Ritesh; Raut, Rajarshi; Mukherjee, A.; Goswami, A.; Ray, S.; Basu, P.; Majumder, H.; Bhattacharya, S.; Dasmahapatra, B.; Sinha, Mandira; Ray, Maitreyee

2004-01-01

The Clover detectors in their add back mode have been seen to be excellent tools for detecting high energy gamma rays (≥ 2 MeV). Recently studies were carried out on the characteristics of a Compton suppressed Clover germanium detector up to 5 MeV using a radioactive 66 Ga (T 1/2 =9.41 h) source for the first time

Damage by the Sitka spruce weevil (Pissodes strobi) and growth patterns for 10 spruce species and hybrids over 26 years in the Pacific Northwest.

Science.gov (United States)

Russel G. Mitchell; Kenneth H. Wright; Norman E. Johnson

1990-01-01

Ten species and hybrids of spruce (Picea spp.) were planted and observed annually for 26 years at three coastal locations in Oregon and Washington to evaluate growth rates and susceptibility to the Sitka spruce weevil (= white pine weevil), Pissodes strobi The 10 spruce were: Sitka spruce, Norway spruce, Lutz spruce, black...

New Approach of Beauveria bassiana to Control the Red Palm Weevil (Coleoptera: Curculionidae) by Trapping Technique.

Science.gov (United States)

Hajjar, M J; Ajlan, A M; Al-Ahmad, M H

2015-04-01

This work is the first study to investigate the efficacy of the commercial formulation of Beauveria bassiana (Broadband) to control adults of red palm weevil (Rhynchophorus ferrugineus (Olivier)). This fungus could be applied as one of the biological tactics in controlling red palm weevil. Bioassay experiments for medium lethal concentrate and medium time to cause death of 50% of red palm weevil adults were carried out. The result showed that the LC50 of B. bassiana (Broadband) was 2.19×10(7) and 2.76×10(6) spores/ml at 9 and 23 d of treatment, respectively. The LT50 was 13.95 and 4.15 d for concentration of 1×10(7) and 1×10(8) spores/ml, respectively, whereas 1×10(9) spores/ml caused 100% mortality after 24 h. Additionally, a red palm weevil pheromone trap was designed to attract the adults to be contaminated with spores of Broadband, which was applied to the sackcloth fabric that coated the internal surfaces of the bucket trap. The mating behavior was studied to determine direct and indirect infection of the spores from male to female and vice versa. The results showed a high efficacy of Broadband suspension at 1×10(9) spores/ml; 40 ml of suspension at this concentration treated to cloth in a trap caused death of contaminated adults with B. bassiana spores directly and indirectly. The 100% mortality was obtained even after 13 d of traps treatment with 40 ml of the suspension at 1×10(9) spores/ml. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Receptor chirality and behavioral specificity of the boll weevil,Anthonomus grandis Boh. (Coleoptera: Curculionidae), for its pheromone, (+)-grandisol.

Science.gov (United States)

Dickens, J C; Mori, K

1989-02-01

Electrophysiological recordings from antennal olfactory receptors and field behavioral experiments showed both male and female boll weevils,Anthonomus grandis Boh. (Coleoptera: Curculionidae), to respond specifically to (+)-grandisol, an enantiomer of compound I of the boll weevil aggregation pheromone. Single-cell recordings revealed antennal olfactory neurons in both male and female weevils keyed to (+)-grandisol. Electroantennograms in response to serial dilutions of the grandisol enaniiomers showed a threshold 100 to 1000 times lower for (+)-grandisol relative to its antipode. In field behavioral experiments, both sexes were significantly more attracted to (+)-grandisol in combination with the three other pheromone components than the combination with (-)-grandisol. When (-)-grandisol was placed with the (+)-enantiomer at equal dosages, a slight although statistically insignificant inhibition occurred. Subsequent field tests showed that the low level of attraction exhibited by (-)-grandisol in combination with the other three pheromone components could be attributed to the other three components alone. These results are in contrast with an earlier study, which found (-)-grandisol to be as attractive as the (+)-enantiomer.

Forbs enhance productivity of unfertilised grass-clover leys and support low-carbon bioenergy

DEFF Research Database (Denmark)

Cong, Wen-Feng; Jing, Jingying; Rasmussen, Jim

2017-01-01

Intensively managed grasslands are dominated by highly productive grass-clover mixtures. Increasing crop diversity by inclusion of competitive forbs may enhance biomass production and sustainable biofuel production. Here we examined if one or all of three forbs (chicory, Cichorium intybus L.; car...

An irradiation marker for mango seed weevil

International Nuclear Information System (INIS)

Heather, N.W.; Lescano, H.G.; Congdon, B.C.

1999-01-01

The objective of this study was to look for a method to determine whether live mango seed weevil, Sternochetus mangifera (Fabricius) present in fruit had been irradiated at a quarantine dose or lower. We looked specifically for anatomical effects on the supra-oesophageal ganglion of larvae and tested a biochemical method for detection of the effects of irradiation on the protein profile of pupae. Neither method was successful. However, because for most international export markets mangoes need only be found free of the pest at inspection sourcing from pest-free production orchards and quality control systems incorporating requisite pest management components could prove practicable and satisfy most markets. (author)

Modelling Gene Flow between Fields of White Clover with Honeybees as Pollen Vectors

DEFF Research Database (Denmark)

Løjtnant, Christina; Boelt, Birte; Clausen, Sabine Karin

2012-01-01

The portion-dilution model is a parametric restatement of the conventional view of animal pollination; it predicts the level of pollinator-mediated gene dispersal. In this study, the model was applied to white clover (Trifolium repens) and its most frequent pollinator, the honeybee (Apis mellifera......). One of the three parameters in the portion-dilution model is the mean number of flowers a pollinator visits in one foraging bout. An alternative method to estimate this parameter was developed that was not depending on pollinator hive-seeking behaviour. The new estimation method, based on nectar......% with an estimated 95% percentile of 70%. The results show that the European Union threshold limit of 0.9% GM admixture for food and feed will likely be exceeded at times and especially organic farmers that do not accept GM admixture and often have clover and clover–grass fields might face challenges with admixture...

Effects of field characteristics on abundance of bumblebees (Bombus spp.) and seed yield in red clover fields

DEFF Research Database (Denmark)

Wermuth, Kirsten Haugaard; Dupont, Yoko L.

2010-01-01

Red clover is a key floral ressource for bumblebees (Bombus spp.).We here investigate variation within and among red clover fields in species richness and abundance of Bombus spp. in addition to Apis mellifera. Bumblebee individuals were grouped into the following functional groups, based on castes...... and tongue length: (1) all queens, (2) all workers, (3) short-tongued workers and (4) long-tongued workers. In 14 study fields, no spatial or diurnal within-field differences were found in abundances of bee groups. However, seasonal differences were detected. On average 6.3±0.6 Bombus spp. were observed...

Effects of the diet on the microbiota of the red palm weevil (Coleoptera: Dryophthoridae.

Directory of Open Access Journals (Sweden)

Matteo Montagna

Full Text Available Rhynchophorus ferrugineus, also known as the red palm weevil, is regarded as the major pest of palm trees. Although studies of the microbiota associated with this species have been performed in recent years, little attention has been dedicated to the influence of the diet in shaping the host bacterial community. Here, we investigated the influence of food sources (i.e. palm tissues vs apple based substrate on the microbial diversity associated with RPW, which was compared with the microbiota associated with wild individuals of the sister species Rhynchophorus vulneratus. The bacterial characterization was performed using a culture independent approach, i.e. the 16S rRNA pyrotag, and a culture dependent approach for a subset of the samples, in order to obtain bacterial isolates from RPW tissues. The bacterial community appeared significantly influenced by diet. Proteobacteria resulted to be the most abundant clade and was present in all the specimens of the three examined weevil groups. Within Proteobacteria, Enterobacteriaceae were identified in all the organs analysed, including hemolymph and reproductive organs. The apple-fed RPWs and the wild R. vulneratus showed a second dominant taxon within Firmicutes that was scarcely present in the microbiota associated with palm-fed RPWs. A comparative analysis on the bacteria associated with the palm tissues highlighted that 12 bacterial genera out of the 13 identified in the plant tissues were also present in weevils, thus indicating that palm tissues may present a source for bacterial acquisition.

Effects of the Diet on the Microbiota of the Red Palm Weevil (Coleoptera: Dryophthoridae)

KAUST Repository

Montagna, Matteo

2015-01-30

Rhynchophorus ferrugineus, also known as the red palm weevil, is regarded as the major pest of palm trees. Although studies of the microbiota associated with this species have been performed in recent years, little attention has been dedicated to the influence of the diet in shaping the host bacterial community. Here, we investigated the influence of food sources (i.e. palm tissues vs apple based substrate) on the microbial diversity associated with RPW, which was compared with the microbiota associated with wild individuals of the sister species Rhynchophorus vulneratus. The bacterial characterization was performed using a culture independent approach, i.e. the 16S rRNA pyrotag, and a culture dependent approach for a subset of the samples, in order to obtain bacterial isolates from RPW tissues. The bacterial community appeared significantly influenced by diet. Proteobacteria resulted to be the most abundant clade and was present in all the specimens of the three examined weevil groups. Within Proteobacteria, Enterobacteriaceae were identified in all the organs analysed, including hemolymph and reproductive organs. The apple-fed RPWs and the wild R. vulneratus showed a second dominant taxon within Firmicutes that was scarcely present in the microbiota associated with palm-fed RPWs. A comparative analysis on the bacteria associated with the palm tissues highlighted that 12 bacterial genera out of the 13 identified in the plant tissues were also present in weevils, thus indicating that palm tissues may present a source for bacterial acquisition.

Acorn fall and weeviling in a northern red oak seedling orchard

Science.gov (United States)

Daniel R. Miller; Scott E. Schlarbaum

2005-01-01

In 2000, we determined levels of damage by acorn weevils (Curculio spp.) and patterns of acorn fall in a northern red oak (Quercus rubra L.) seedling orchard in eastern Tennessee. The mean (±SE) production of acorns among 43 selected trees was 5,930 ± 586 acorns per tree with a maximum production level of 16,969 acorns for one tree...

Some recent developments in white-pine weevil research in the Northeast

Science.gov (United States)

H. A. Jaynes

1958-01-01

Eastern white pine is one of the most important sawtimber species in the Northeast. This species would have still greater potential value were it not for the white-pine weevil, Pissodes strobi (Peck), its most serious insect pest. This is a native insect that occurs throughout the range of eastern white pine. A large percentage of the white pines in...

Preferential edge habitat colonization by a specialist weevil, Rhinoncomimus latipes (Coleoptera: Curculionidae)

Science.gov (United States)

J.A. Hough-Goldstein; E. Lake; V. D' Amico; S.H. Berg

2012-01-01

Understanding the behavioral basis of dispersal and colonization is critical in biological control systems, where success of a natural enemy depends in part on its ability to find and move to new host patches. We studied behavior of the specialist weevil Rhinoncomimus latipes Korotyaev, a biological control agent of mile-a-minute weed, ...

Loss of phytotelmata due to an invasive bromeliad-eating weevil and its potential effects on faunal diversity and biogeochemical cycles

Science.gov (United States)

Cooper, Teresa M.; Frank, J. Howard; Cave, Ronald D.

2014-01-01

Epiphytic tank bromeliads are important ecosystem engineers because they form phytotelmata that create habitat, increase species richness and abundance, create water sources and nutrient reservoirs in the canopy, and collect and redirect nutrients in forest ecosystems. Native bromeliad populations have been devastated in Florida (USA) because an invasive bromeliad-eating weevil (Metamasius callizona) has been destroying the plants. Tillandsia utriculata is a tank bromeliad that was once widespread from central to south Florida. Its populations have been hit hard by the weevil and are declining rapidly. This study quantifies the mortality rate caused by the weevil in a population of T. utriculata at the Enchanted Forest Sanctuary in central Florida and estimates the associated loss of phytotelmata. Estimations of phytotelmata were calculated for the T. utriculata baseline population, the population at 6 months into the study when 87% of the population was destroyed, and at the end of the study when less than 3% of the bromeliad population remained (99% of all deaths were caused by the weevil). The baseline population contained 16,758 L of water. At six months, there were 3180 L, and at the end of the study, there were 408 L. The loss of phytotelmata results in the loss of habitat, a decrease in biological diversity, and altered water and nutrient cycles and availability.

Changes in soil solution Zn and pH and uptake of Zn by arbuscular mycorrhizal red clover in Zn-contaminated soil.

Science.gov (United States)

Li, X; Christie, P

2001-01-01

Red clover plants inoculated with Glomus mosseae were grown in a sterile pasture soil containing 50 mg Zn kg(-1) in 'Plexiglas' (acrylic) containers with nylon net partitions (30 microm mesh) designed to separate the soil into a central root zone and two outer zones for hyphal growth with no root penetration. Two porous plastic soil moisture samplers were installed in each pot, one in the root compartment and the other in one of the hyphal compartments. The soil in the outer compartments was amended with one of the four application rates of Zn (as ZnSO4) ranging from 0 to 1000 mg kg(-1). Non-mycorrhizal controls were included, and there were five replicates of each treatment in a randomised block in a glasshouse. Uninoculated plants received supplementary P to avoid yield limitation due to low soil P status. Plants grew in the central compartment for nine weeks. Soil moisture samples were collected 4, 24 and 62 days after sowing to monitor changes in the Zn concentration and pH of the soil solution. At harvest, the mean mycorrhizal infection rate of inoculated plants ranged from 29% to 34% of total root length and was little affected by Zn application. Root and shoot yields were not affected by mycorrhizal infection. Plant Zn concentration and uptake were lower in mycorrhizal plants than non-mycorrhizal controls, and this effect was more pronounced with increasing Zn application rate to the soil. Soil solution Zn concentrations were lower and pH values were higher in mycorrhizal treatments than non-mycorrhizal controls and the mycorrhiza effect was more pronounced at higher Zn application rates. The protective effect of mycorrhiza against plant Zn uptake may have been associated with changes in Zn solubility mediated by changes in the soil solution pH, or by immobilisation of Zn in the extraradical mycelium.

Eradication of the cotton boll weevil (Anthonomus grandis) in the United States - A successful multi-regional approach

International Nuclear Information System (INIS)

Cunningham, Gary L.; Grefenstette, William J.

2000-01-01

The cotton boll weevil, Anthonomus grandis Boheman, is believed to have entered the US from Mexico and was first detected in South Texas in 1892. Since that time, the pest has spread throughout most of the nation's cotton-producing areas and has become the industry's number one nemesis. More than US$13 billion in economic losses have occurred since its introduction, with recent annual expenditures of more than US$300 million for control costs alone. Although the weevil has been eradicated from over 4 million acres, its presence in non-programme areas continues to dictate production practices within the mid-south, Texas and Oklahoma

Environmental Impact Research Program: White Clover (Trifolium repens). Section 7.3.5, US Army Corps of Engineers Wildlife Resources Management Manual.

Science.gov (United States)

1986-07-01

types where they are common (Kohn and Mooty 1971). Rumen analyses of white-tailed deer in Montana showed that forbs comprised 80% of summer samples...frequency of occurrence in deer rumens collected from January through March in the Northern Black Hills. Bluegrass- white clover meadows are also...CAUTIONS AND LIMITATIONS White clover, like most legumes, occasionally causes bloat in animals, particularly cattle and sheep that have overfilled

The "clover technique" as a novel approach for correction of post-traumatic tricuspid regurgitation.

Science.gov (United States)

Alfieri, O; De Bonis, M; Lapenna, E; Agricola, E; Quarti, A; Maisano, F

2003-07-01

To describe a novel technique, named "clover," to correct complex post-traumatic tricuspid valve lesions. Five patients with severe post-traumatic tricuspid insufficiency underwent valve reconstruction with the clover technique, a new surgical approach that consists of stitching together the middle point of the free edges of the tricuspid leaflets, producing a clover-shaped valve. The mechanism of tricuspid regurgitation was complex in all patients, and right ventricular function was always moderately to severely depressed. An echocardiographic study was performed after cardiopulmonary bypass, at discharge, and at follow-up. Cardiopulmonary bypass time was 32 +/- 6.3 minutes and crossclamp time was 23 +/- 7.4. There was no hospital mortality or morbidity. Intraoperative transesophageal and predischarge transthoracic echocardiography showed perfect results in all patients. No late deaths occurred. At the latest follow-up, extending to 14.2 months (mean 11.3; median 12.4), all patients were asymptomatic (New York Heart Association class I) with trivial (2 patients) or no residual regurgitation (3 patients) on 2-dimensional echocardiogram. No transvalvular gradient was revealed in any patient. A significant reduction of the right ventricular end-diastolic dimensions was noted as well (from 54 +/- 7.1 mm to 40 +/- 7.5 mm, P tricuspid valve repair in case of severe traumatic tricuspid valve insufficiency, leading to very satisfactory mid-term results even in the presence of complex lesions or dilatation and deterioration of the right ventricle.

Honeybees tolerate cyanogenic glucosides from clover nectar and flowers

DEFF Research Database (Denmark)

Lecocq, Antoine; Green, Amelia Ann; Pinheiro de Castro, Érika Cristina

2018-01-01

Honeybees (Apis mellifera) pollinate flowers and collect nectar from many important crops. White clover (Trifolium repens) is widely grown as a temperate forage crop, and requires honeybee pollination for seed set. In this study, using a quantitative LC-MS (Liquid Chromatography-Mass Spectrometry...... indicates that plant secondary metabolites found in nectar may protect pollinators from disease or predators. In a laboratory survival study with chronic feeding of secondary metabolites, we show that honeybees can ingest the cyanogenic glucosides linamarin and amygdalin at naturally occurring...

Plant genotypes affect aboveground and belowground herbivore interactions by changing chemical defense.

Science.gov (United States)

Li, Xiaoqiong; Guo, Wenfeng; Siemann, Evan; Wen, Yuanguang; Huang, Wei; Ding, Jianqing

2016-12-01

Spatially separated aboveground (AG) and belowground (BG) herbivores are closely linked through shared host plants, and both patterns of AG-BG interactions and plant responses may vary among plant genotypes. We subjected invasive (USA) and native (China) genotypes of tallow tree (Triadica sebifera) to herbivory by the AG specialist leaf-rolling weevil Heterapoderopsis bicallosicollis and/or the root-feeding larvae of flea beetle Bikasha collaris. We measured leaf damage and leaves rolled by weevils, quantified beetle survival, and analyzed flavonoid and tannin concentrations in leaves and roots. AG and BG herbivores formed negative feedbacks on both native and invasive genotypes. Leaf damage by weevils and the number of beetle larvae emerging as adults were higher on invasive genotypes. Beetles reduced weevil damage and weevils reduced beetle larval emergence more strongly for invasive genotypes. Invasive genotypes had lower leaf and root tannins than native genotypes. BG beetles decreased leaf tannins of native genotypes but increased root tannins of invasive genotypes. AG herbivory increased root flavonoids of invasive genotypes while BG herbivory decreased leaf flavonoids. Invasive genotypes had lower AG and BG herbivore resistance, and negative AG-BG herbivore feedbacks were much stronger for invasive genotypes. Lower tannin concentrations explained overall better AG and BG herbivore performances on invasive genotypes. However, changes in tannins and flavonoids affected AG and BG herbivores differently. These results suggest that divergent selection on chemical production in invasive plants may be critical in regulating herbivore performances and novel AG and BG herbivore communities in new environments.

First record of plicidentine in Synapsida and patterns of tooth root shape change in Early Permian sphenacodontians.

Science.gov (United States)

Brink, Kirstin S; LeBlanc, Aaron R H; Reisz, Robert R

2014-11-01

Recent histological studies have revealed a diversity of dental features in Permo-Carboniferous tetrapods. Here, we report on the occurrence of plicidentine (infolded dentine around the base of the tooth root) in Sphenacodontia, the first such documentation in Synapsida, the clade that includes mammals. Five taxa were examined histologically, Ianthodon schultzei, Sphenacodon ferocior, Dimetrodon limbatus, Dimetrodon grandis, and Secodontosaurus obtusidens. The tooth roots of Ianthodon possess multiple folds, which is generally viewed as the primitive condition for amniotes. Sphenacodon and D. limbatus have distinctive "four-leaf clover"-shaped roots in cross section, whereas Secodontosaurus has an elongate square shape with only subtle folding. The most derived and largest taxon examined in this study, D. grandis, has rounded roots in cross section and therefore no plicidentine. This pattern of a loss of plicidentine in sphenacodontids supports previous functional hypotheses of plicidentine, where teeth with shallow roots require folds to increase the area of attachment to the tooth-bearing element, whereas teeth with long roots do not. This pattern may also reflect differences in diet between co-occurring sphenacodontids as well as changes in feeding niche through time, specifically in the apex predator Dimetrodon.

Quantification of dichlorvos released from kill strips used in boll weevil eradication programs

Science.gov (United States)

Two types of kill strips, Hercon Vaportape II and Plato Insecticide Strip, are used by boll weevil, Anthonomus grandis (Boheman), eradication programs in the U.S. Both types utilize dichlorvos as the killing agent and are marketed to last up to a month in traps. Consequently, programs typically re...

NUTRITIVE VALUES OF SOME ANNUAL CLOVERS (Trifolium sp. AT DIFFERENT GROWTH STAGES

Directory of Open Access Journals (Sweden)

A TEKELI

2006-05-01

Full Text Available This study was conducted between the years of 2001-2002 in the experimental area and laboratory of Field Crops Department of Agriculture Faculty in Trakya University, Tekirdağ (Turkey. Five different clovers [Persian (Trifolium resupinatum L. var. majus Boiss., Mediterranean (T. spumosum L., narrow-leaved (T. angustifolium L., hedgehog (T. echinatum M. Bieb. and lappa (T. lappaceum L. clovers] were used. Each plot consisted of 8 rows with a length of 5 m. Row spacing of 30 cm and sowing rate of 10 kg ha-1 were used. Sowing times were on 2.25.2001 and on 2.28.2002. Plots were not irrigated and fertilized after sown and harvest. One cut was taken in both years at 4 growing stages such as pre-bud, pre-bloom, 50% bloom and full-bloom. The central 1 m-2 sections was cut at ground level for dry matter. Approximately 500g samples were dried at 55 °C for 24 hours and stored for one day at room temperature then found dry matter. Crude protein (% was determined by Kjeldahl method.

Alternative food sources and overwintering feeding behavior of the boll weevil, Anthonomus grandis boheman (Coleoptera: Curculionidae) under the tropical conditions of Central Brazil.

Science.gov (United States)

Ribeiro, Paulina de A; Sujii, Edison R; Diniz, Ivone R; Medeiros, Maria A de; Salgado-Labouriau, Maria L; Branco, Marina C; Pires, Carmen S S; Fontes, Eliana M G

2010-01-01

The boll weevil causes serious damage to the cotton crop in South America. Several studies have been published on this pest, but its phenology and behavior under the tropical conditions prevailing in Brazil are not well-known. In this study the feeding behavior and main food sources of adult boll weevils throughout the year in Central Brazil was investigated. The digestive tract contents of insects captured in pheromone traps in two cotton fields and two areas of native vegetation (gallery forest and cerrado sensu stricto) were analyzed. The insect was captured all through the year only in the cerrado. It fed on pollen of 19 different plant families, on Pteridophyta and fungi spores and algae cysts. Simpson Index test showed that the cerrado provided greater diversity of pollen sources. In the beginning of the cotton cycle, the plant families used for pollen feeding were varied: in cotton area 1, the weevil fed on Poaceae(50%), Malvaceae and Smilacaceae (25% each); in cotton area 2 the pollen sources were Malvaceae (50%), Asteraceae (25%) and Fabaceae and Clusiaceae (25% each); in the cerrado they were Chenopodiaceae (67%) and Scheuchzeriaceae (33%). No weevils were collected in the gallery forest in this period. After cotton was harvested, the family Smilacaceae was predominant among the food plants exploited in all the study areas. These results help to explain the survivorship of adult boll weevil during cotton fallow season in Central Brazil and they are discussed in the context of behavioral adaptations to the prevailing tropical environmental conditions.

The performance of a white clover-based dairy system in comparison with a grass/fertiliser-N system. II. Animal production, economics and environment

NARCIS (Netherlands)

Schils, R.L.M.; Boxem, T.; Jagtenberg, C.J.; Verboom, M.C.

2000-01-01

The performance of a white clover based dairy system in comparison with a grass/fertiliser-N system was studied during three years. Both systems had 59 cows, plus young stock, on an area of 40.6 ha for grass/clover and 34.4 ha for grass/fertiliser-N. During the grazing season, the cows in both

Searls prairie clover (Dalea searlsiae) for rangeland revegetation: Phenotypic and genetic evaluations

Science.gov (United States)

Kishor Bhattarai; Shaun Bushman; Douglas A. Johnson; John G. Carman

2011-01-01

Few North American legumes are available for use in rangeland revegetation in the western USA, but Searls prairie clover [Dalea searlsiae (A. Gray) Barneby] is one that holds promise. Commercial-scale seed production of this species could address the issues of unreliable seed availability and high seed costs associated with its wildland seed collection. To evaluate its...

Employing in vitro directed molecular evolution for the selection of α-amylase variant inhibitors with activity toward cotton boll weevil enzyme.

Science.gov (United States)

da Silva, Maria Cristina Mattar; Del Sarto, Rafael Perseghini; Lucena, Wagner Alexandre; Rigden, Daniel John; Teixeira, Fabíola Rodrigues; Bezerra, Caroline de Andrade; Albuquerque, Erika Valéria Saliba; Grossi-de-Sa, Maria Fatima

2013-09-20

Numerous species of insect pests attack cotton plants, out of which the cotton boll weevil (Anthonomus grandis) is the main insect in Brazil and must be controlled to avert large economic losses. Like other insect pests, A. grandis secretes a high level of α-amylases in the midgut lumen, which are required for digestion of carbohydrates. Thus, α-amylase inhibitors (α-AIs) represent a powerful tool to apply in the control of insect pests. Here, we applied DNA shuffling and phage display techniques and obtained a combinatorial library containing 10⁸ α-AI variant forms. From this library, variants were selected exhibiting in vitro affinity for cotton boll weevil α-amylases. Twenty-six variant sequences were cloned into plant expression vectors and expressed in Arabidopsis thaliana. Transformed plant extracts were assayed in vitro to select specific and potent α-amylase inhibitors against boll weevil amylases. While the wild type inhibitors, used to create the shuffled library, did not inhibit the A. grandis α-amylases, three α-AI mutants, named α-AIC3, α-AIA11 and α-AIG4 revealed high inhibitory activities against A. grandis α-amylases in an in vitro assay. In summary, data reported here shown the potential biotechnology of new α-AI variant genes for cotton boll weevil control. Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.

Microbial protein synthesis, digestion and lactation responses of cows to grass or grass-red clover silage diet supplemented with barley or oats

Directory of Open Access Journals (Sweden)

A. VANHATALO

2008-12-01

Full Text Available The study was conducted to evaluate effects of silage type (grass-red clover vs. pure grass and grain supplement (oats vs. barley on rumen fermentation, post-ruminal nutrient flows, diet digestion and milk production. Four primiparous Finnish Ayrshire cows fitted with cannulae in the rumen and duodenum were used in a 4 × 4 Latin square experiment with four 28-d experimental periods and 2 × 2 factorial arrangements of treatments. Using red clover-containing (40% silage rather than pure grass silage had minor effects on rumen fermentation or diet digestion but increased non-ammonia nitrogen (N flow in terms of increased flows of microbial and dietary N entering to the small intestine. This was reflected as a reduced ruminal N degradability on grass-red clover diets. Furthermore, grass-red clover diets in comparison to grass silage diets increased milk lactose concentration and yields of milk, protein and lactose. Feeding oats in replacement for barley had minor effects on rumen fermentation or post-ruminal non-ammonia N flows but reduced digestibility of organic matter and neutral detergent fibre in the diet. Using oats rather than barley increased yields of milk and lactose but reduced milk protein concentration. Oats also increased proportions of C18:0 and C18:1 in milk fat and reduced those of C10:0 to C16:0. It is concluded that inclusion of red clover and replacement of barley with oats in grass silage based diets have beneficial effects in dairy cow production.;

Boll weevil (Anthonomus grandis) population genomics as a tool for monitoring and management

Science.gov (United States)

Despite the success of eradication efforts across most of the cotton-producing regions of the U.S., the cotton boll weevil (Anthonomus grandis grandis Boheman) remains a major pest of cotton in much of the New World. The area along the Texas border with northern Mexico has been a particularly troub...

Radiation induced changes in the cuticular hydrocarbons of the granary weevil and their relationships to desiccation and adult mortality: Half yearly report, February 16 to August 15, 1987

International Nuclear Information System (INIS)

Sriharan, S.

1987-01-01

This report outlines studies on the rate of moisture-loss in irradiated weevils and correlation loss of water with mortality. Further changes in the cuticular hydrocarbons of weevils as a result of gamma radiation were determined. 2 figs., 10 tabs

Cytoskeleton-amyloplast interactions in sweet clover

Science.gov (United States)

Guikema, J. A.; Hilaire, E.; Odom, W. R.; Spooner, B. S. (Principal Investigator)

1993-01-01

The distribution of organelles within columella cells of sweet clover was examined by transmission electron microscopy following growth under static or clinorotating conditions. A developmentally conditioned polarity was observed, with a proximal location of the nucleus and a distal accumulation of the endoplasmic reticulum. This polarity was insensitive to clinorotation. In contrast, clinorotation altered the location of amyloplasts. Application of cytoskeletal poisons (colchicine, cytochalasin D, taxol, and phalloidin), especially during clinorotation, had interesting effects on the maintenance of columella cell polarity, with a profound effect on the extent, location, and structure of the endoplasmic reticulum. The site of cytoskeletal interactions with sedimenting amyloplasts is thought to be the amyloplast envelope. An envelope fraction, having over 17 polypeptides, was isolated using immobilized antibody technology, and will provide a means of assessing the role of specific peptides in cytoskeleton/amyloplast interactions.

Biochar application rate affects biological nitrogen fixation in red clover conditional on potassium availability

NARCIS (Netherlands)

Mia, S.; van Groeningen, J.W.; Van de Voorde, T.F.J.; Oram, N.J.; Bezemer, T.M.; Mommer, Liesje; Jeffery, S.

2014-01-01

Increased biological nitrogen fixation (BNF) by legumes has been reported following biochar application to soils, but the mechanisms behind this phenomenon remain poorly elucidated. We investigated the effects of different biochar application rates on BNF in red clover (Trifolium pratense L.). Red

Sensitivity of the quarantine pest rough sweetpotato weevil, Blosyrus asellus to postharvest irradiation treatment

Science.gov (United States)

Rough sweetpotato weevil, Blosyrus asellus (Olivier), is a new quarantine pest of Hawaii sweetpotatoes. Currently, sweetpotatoes can be exported from Hawaii to the U.S. mainland using a postharvest irradiation treatment of 150 Gy to control three other regulated insect pests. Studies were conducted...

Starvation-induced morphological responses of the boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae)

Science.gov (United States)

Status of the boll weevil, Anthonomus grandis grandis Boheman, as a pest of cotton (Gossypium spp.) in the United States has diminished because of progress by eradication programs. However, this pest remains of critical importance in South America, and intractable populations in extreme South Texas ...

Effects of High Carbon Dioxide Level on the Emergence of Oil Palm Pollinating Weevil, Elaeidobius Kamerunicus

International Nuclear Information System (INIS)

Amanina, N.S.; Hasnudin, M.Y.; Haniff, M.H.; Roslan, M.N.; A'fifah, A.R.; Ramle, M.

2016-01-01

Elaeidobius kamerunicus is the main pollinating insect of oil palm in Malaysia. The increase of ambient carbon dioxide (CO 2 ) may promote greater crop growth and yield of oil palm. However, E. kamerunicus' adaptability and survival under high CO 2 level are still unknown. An oil palm weevil emergence study was conducted in plant growth chambers with two CO 2 levels, 400 Parts Per Million and 800 Parts Per Million. The plant growth chambers were set at 27 degree celcius and 70% relative humidity for the entire study period. Spikelets were taken from apical, middle and basal regions of anthesising male inflorescences from 6-year old DxP palms under normal field conditions. The sampled spikelets were placed in clear plastic tubes with both open ends covered with muslin cloth. The emergence of adults was observed at two-day interval until 10 days after incubation. The total number of weevils which emerged from the spikelets at 400 Parts Per Million and 800 Parts Per Million CO 2 levels were 240 and 233 individuals, respectively. Doubling the ambient CO 2 level to 800 Parts Per Million had no effect on E. kamerunicus emergence in controlled condition. Further study on oil palm weevil adaptability and survival under high CO 2 level is needed to provide information on the effects of future climate change scenario and oil palm yield. (author)

External and internal structure of weevils (Insecta: Coleoptera) investigated with phase-contrast X-ray imaging

International Nuclear Information System (INIS)

Hoennicke, M.G.; Cusatis, C.; Rigon, L.; Menk, R.-H.; Arfelli, F.; Foerster, L.A.; Rosado-Neto, G.H.

2010-01-01

Weevils (Coleoptera: Curculionidae) are identified by the external structure (dorsal, ventral and lateral features) and also by internal structure. The genitalia can be used to distinguish the sex and to identify the insects when the external structure appears identical. For this purpose, a destructive dissecting microscopy procedure is usually employed. In this paper, phase contrast X-ray imaging (radiography and tomography) is employed to investigate the internal structure (genitalia) of two entire species of weevils that presents very similar external structures (Sitophilus oryzae and Sitophilus zeamais). The detection of features, which looks like the genital structure, shows that such non-destructive technique could be used as an alternative method for identification of insects. This method is especially useful in examining the internal features of precious species from museum collections, as already described in the recent literature.

Phenotypic and genetic characterization of western prairie clover collections from the western USA

Science.gov (United States)

Kishor Bhattarai; B. Shaun Bushman; Douglas A. Johnson; John G. Carman

2010-01-01

Few North American legumes are available for rangeland revegetation in the semiarid western United States. Western prairie clover (Dalea ornata [Douglas ex Hook.] Eaton & J. Wright) is a perennial legume with desirable forage characteristics and is distributed in the northern Great Basin, Snake River Basin, and southern Columbia Plateau. Understanding the...

CHEMICAL CONTROL OF BEAN WEEVIL, ACANTHOSCELIDES OBTECTUS SAY IN STORAGE CONDITION

Directory of Open Access Journals (Sweden)

M PORCA

2003-12-01

Full Text Available The paper presents the positive results obtained by some pesticides applied against the bean weevil - Acanthoscelides obtectus Say, after a synthetic rewiew of the potential chemical methods which may be used in the chemical control of the insectes harmful to the stored bean seeds. The chemical control is realised treatments wits syntetic pyrethroid (permetrin, deltametrin and organophosphoric insecticides (malation, pirimifos metil, fenitrotion and chlrorpirifos-metil.

Alternative food sources and over wintering feeding behavior of the boll weevil, Anthonomus grandis boheman (coleoptera: curculionidae) under the tropical conditions of central Brazil

International Nuclear Information System (INIS)

Ribeiro, Paulina de A.; Sujii, Edison R.; Pires, Carmen S.S.; Fontes, Eliana M.G.; Diniz, Ivone R.; Salgado-Labouriau, Maria L.

2010-01-01

The boll weevil causes serious damage to the cotton crop in South America. Several studies have been published on this pest, but its phenology and behavior under the tropical conditions prevailing in Brazil are not well-known. In this study the feeding behavior and main food sources of adult boll weevils throughout the year in Central Brazil was investigated. The digestive tract contents of insects captured in pheromone traps in two cotton fields and two areas of native vegetation (gallery forest and cerrado sensu stricto) were analyzed. The insect was captured all through the year only in the cerrado. It fed on pollen of 19 different plant families, on Pteridophyta and fungi spores and algae cysts. Simpson Index test showed that the cerrado provided greater diversity of pollen sources. In the beginning of the cotton cycle, the plant families used for pollen feeding were varied: in cotton area 1, the weevil fed on Poaceae (50%), Malvaceae and Smilacaceae (25% each); in cotton area 2 the pollen sources were Malvaceae (50%), Asteraceae (25%) and Fabaceae and Clusiaceae (25% each); in the cerrado they were Chenopodiaceae (67%) and Scheuchzeriaceae (33%). No weevils were collected in the gallery forest in this period. After cotton was harvested, the family Smilacaceae was predominant among the food plants exploited in all the study areas. These results help to explain the survivorship of adult boll weevil during cotton fallow season in Central Brazil and they are discussed in the context of behavioral adaptations to the prevailing tropical environmental conditions. (author)

Alternative food sources and over wintering feeding behavior of the boll weevil, Anthonomus grandis boheman (coleoptera: curculionidae) under the tropical conditions of central Brazil

Energy Technology Data Exchange (ETDEWEB)

Ribeiro, Paulina de A.; Sujii, Edison R.; Pires, Carmen S.S.; Fontes, Eliana M.G. [EMBRAPA Recursos Geneticos e Biotecnologia (CENARGEN), Brasilia, DF (Brazil)], e-mail: paulina723@hotmail.com, e-mail: sujii@cenargen.embrapa.br, e-mail: cpires@cenargen.embrapa.br, e-mail: eliana@cenargen.embrapa.br; Diniz, Ivone R. [Universidade de Brasilia (UnB), DF (Brazil). Dept. de Zoologia], e-mail: irdiniz@unb.br; Medeiros, Maria A. de; Branco, Marina C. [EMBRAPA Hortalicas, Brasilia, DF (Brazil)], e-mail: medeiros@cnph.embrapa.br, e-mail: marina@cnph.embrapa.br; Salgado-Labouriau, Maria L. [Universidade de Brasilia (UnB), DF (Brazil). Dept. de Geologia], e-mail: mlea@unb.br

2010-01-15

The boll weevil causes serious damage to the cotton crop in South America. Several studies have been published on this pest, but its phenology and behavior under the tropical conditions prevailing in Brazil are not well-known. In this study the feeding behavior and main food sources of adult boll weevils throughout the year in Central Brazil was investigated. The digestive tract contents of insects captured in pheromone traps in two cotton fields and two areas of native vegetation (gallery forest and cerrado sensu stricto) were analyzed. The insect was captured all through the year only in the cerrado. It fed on pollen of 19 different plant families, on Pteridophyta and fungi spores and algae cysts. Simpson Index test showed that the cerrado provided greater diversity of pollen sources. In the beginning of the cotton cycle, the plant families used for pollen feeding were varied: in cotton area 1, the weevil fed on Poaceae (50%), Malvaceae and Smilacaceae (25% each); in cotton area 2 the pollen sources were Malvaceae (50%), Asteraceae (25%) and Fabaceae and Clusiaceae (25% each); in the cerrado they were Chenopodiaceae (67%) and Scheuchzeriaceae (33%). No weevils were collected in the gallery forest in this period. After cotton was harvested, the family Smilacaceae was predominant among the food plants exploited in all the study areas. These results help to explain the survivorship of adult boll weevil during cotton fallow season in Central Brazil and they are discussed in the context of behavioral adaptations to the prevailing tropical environmental conditions. (author)

Effect of crop sanitation on banana weevil Cosmopolites sordidus (Germar) populations and associated damage

NARCIS (Netherlands)

Masanza, M.

2003-01-01

The banana weevil, Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae) is a serious pest of bananas. However, its ecology is not well elucidated especially in East Africa where plantations are up to 50 years old and are under various management and cropping systems. No single

Olfactory responses of banana weevil predators to volatiles from banana pseudostem tissue and synthetic pheromone

NARCIS (Netherlands)

Tinzaara, W.; Gold, C.S.; Dicke, M.; Huis, van A.

2005-01-01

As a response to attack by herbivores, plants can emit a variety of volatile substances that attract natural enemies of these insect pests. Predators of the banana weevil, Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae) such as Dactylosternum abdominale (Coleoptera: Hydrophilidae) and

Radiosensitivity studies on the different stages and ages of orchid weevil, orchidophilus aterrimus (waterhouse)

International Nuclear Information System (INIS)

Manoto, E.C.; Obra, G.B.; Reyes, M.R.; Resilva, S.R.

1996-01-01

The effect of different radiation doses on the different stages and ages of orchid weevil, Orchidophilus aterrimus (Waterhouse) was investigated. Among the different stages, the egg was found the most sensitive while the adult weevil was the most resistant to gamma radiation. The younger the insect within a stage, the more sensitive they are to the lethal effect of radiation. For instance, one-to three-day-old eggs were found most sensitive followed by four-to seven-day-old eggs, two- to four-day-old and 30-day-old larvae and early pupae. Late pupae and adults were the most radioresistant when irradiated with doses ranging from 150 to 450 Gy. Furthermore, young adults treated with 150 to 460 Gy did not lay any eggs while mature adults lay a few eggs but none of them hatched. Our data indicate that gamma radiation may be used as an alternative quarantine treatment for disinfestation of orchids. (author)

Pine weevil feeding on Norway spruce bark has a stronger impact on needle VOC emissions than enhanced ultraviolet-B radiation

International Nuclear Information System (INIS)

Blande, James D.; Turunen, Katariina; Holopainen, Jarmo K.

2009-01-01

Plants can respond physiologically to damaging ultraviolet-B radiation by altering leaf chemistry, especially UV absorbing phenolic compounds. However, the effects on terpene emissions have received little attention. We conducted two field trials in plots with supplemented UV-B radiation and assessed the influence of feeding by pine weevils, Hylobius abietis L., on volatile emissions from 3-year old Norway spruce trees (Picea abies L. Karst.). We collected emissions from branch tips distal to the feeding weevils, and from whole branches including the damage sites. Weevil feeding clearly induced the emission of monoterpenes and sesquiterpenes, particularly linalool and (E)-β-farnesene, from branch tips, and the sums of monoterpenes and sesquiterpenes emitted by whole branches were substantially increased. We discovered little effect of UV-B radiation up to 30% above the ambient level on volatile emissions from branch tips distal to damage sites, but there was a possible effect on bark emissions from damage sites. - Chronic exposure to enhanced UV-B radiation has little effect on volatile emissions of Norway spruce

Irradiation as a potential phytosanitary treatment for the mango pulp weevil sternochetus frigidus (Fabr.) (Coleoptera: Curculionidae) in Philippine sugar mango

International Nuclear Information System (INIS)

Obra, Glenda B.; Resilva, Sotero S.; Lorenzana, Louella Rowena J.

2013-01-01

Irradiation was explored as a method of quarantine disinfestation treatment for the mango pulp weevil Sternochetus frigidus (Fabr.) S. frigidus is an important quarantine pest preventing the export of mangoes from the Philippines to countries with strict quarantine regulations. Mangoes obtained from Guimaras Island are exempt from this ban as they are certified to be free from seed weevil and pulp weevil infestation. In the dose-response tests, S. frigidus larvae, pupae and adults in mangoes were irradiated at target doses of 25, 50, 75, 100, 150, 300 and 400 Gy. The number of eggs laid by adult females decreased with increasing dose. Treatment with irradiation doses ≥75 Gy resulted in sterility in adults developing from larvae and pupae while doses of ≥100 Gy resulted in sterility in irradiated adults. The adult was the most tolerant stage based on sterility or prevention of adult reproduction. Significant differences were observed in adult longevity among treatment doses in S. frigidus, but none between sexes and in the interaction between dose and sex. (author)

Effects of feeding level and NDF content of grass-clover silages on chewing activity, fecal particle size and NDF digestibility in dairy heifers

DEFF Research Database (Denmark)

Schulze, Anne-Katrine Skovsted; Weisbjerg, Martin Riis; Nørgaard, Peder

2014-01-01

intake (PRumination time per kg DM intake (Pcontents (Prumination with greater...... NDF content (Prumination time increased with greater NDF content (Pcontent (P...The objective of this study was to assess effects of feed intake and NDF content of highly digestible grass-clover silage on chewing behavior, fecal particle size distribution and apparent digestibility in restrictively fed heifers. Four grass-clover silages (Lolium perenne, Trifolium pratense...

Local and neighboring patch conditions alter sex-specific movement in banana weevils.

Science.gov (United States)

Carval, Dominique; Perrin, Benjamin; Duyck, Pierre-François; Tixier, Philippe

2015-12-01

Understanding the mechanisms underlying the movements and spread of a species over time and space is a major concern of ecology. Here, we assessed the effects of an individual's sex and the density and sex ratio of conspecifics in the local and neighboring environment on the movement probability of the banana weevil, Cosmopolites sordidus. In a "two patches" experiment, we used radiofrequency identification tags to study the C. sordidus movement response to patch conditions. We showed that local and neighboring densities of conspecifics affect the movement rates of individuals but that the density-dependent effect can be either positive or negative depending on the relative densities of conspecifics in local and neighboring patches. We demonstrated that sex ratio also influences the movement of C. sordidus, that is, the weevil exhibits nonfixed sex-biased movement strategies. Sex-biased movement may be the consequence of intrasexual competition for resources (i.e., oviposition sites) in females and for mates in males. We also detected a high individual variability in the propensity to move. Finally, we discuss the role of demographic stochasticity, sex-biased movement, and individual heterogeneity in movement on the colonization process.

SPECIES COMPOSITION AND ECOLOGICAL-ZOOGEOGRAPHICAL ANALYSIS OF THE WEEVILS (CURCULIONIDAE IN THE INNER-MOUNTAINOUS DAGESTAN

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Gul'nara Magomedovna Mukhtarova

2015-01-01

Full Text Available Aim. The purpose of this research study is to determine the species composition of the study area, ecological and zoogeographical analysis, identification of trophic specialization, showing the dependence of the weevils to certain life forms of plants. Location. The work is based on observations and contributions received as a result of complex expeditions Ecological-geographical faculty of the Dagestan State University and the Institute of Applied Ecology in the territory of Inner Mountainous Dagestan.Methods. Materials presented of collection: of assistant professor of the Department Biology and Biodiversity Dagestan State University - Gul'nara Mukhtarova (Magomedova 1995 – 2002; of professor of the Department Biology and Biodiversity Dagestan State University - Madina Ismailova 1990, 1992, 1995 – 2002; of professor of the Department Biology and Biodiversity Dagestan State University - Gaiirbeg Abdurakhmanov 1985, 1986, 1987, 1996 – 2002. Analysis ranges of species of the studied fauna carried out using the classical works on zoogeography.Results. As a result of faunal studies for the study area recorded 415 species of the weevils. Conducted research and analysis of published data identified food connections for 94 % species of the fauna of weevils in the study area. Zoogeographical analysis of the faunal showed that the Palaearctic complex are most numerous and presented by 109 species (26%, the Caucasian complex – 83 (20%, the Steppe complex – 47 (11.3%, the European complex – 36 (8,67%, the Euro-Mediterranean complex – 30, the Turan complex – 28, the European-Siberian complex – 28, the Eastern Mediterranean complex 19, the Mediterranean complex – 17 (4.1%, the Persian complex – 10, the Holarctic complex – 5, the Cosmopolitan complex – 2, and the Paleotropics complex – 1. Main conclusions. Analysis of the findings shows a great similarity in the composition of the forage base of weevils for the different areas

Molecular Diagnostic for Boll Weevil (Coleoptera: Curculionidae) Based on Amplification of Three Species-specific Microsatellites

Science.gov (United States)

The boll weevil, Anthonomus grandis Boheman (Coleoptera: Curculionidae), is a serious pest of cultivated cotton in the Americas, and reinfestation of zones from which they have been eradicated is of perpetual concern. Extensive arrays of pheromone traps monitor for reintroductions, but occasionally...

Chitinolitic activity in proteic extracts of Bacillus thuringiensis toxic to boll weevil (Anthonomus grandis)

Energy Technology Data Exchange (ETDEWEB)

Silva, T.S; Rocha, T.L. [EMBRAPA Recursos Geneticos e Biotecnologia, DF (Brazil); Vasconcelos, E.A.R [Universidade de Brasilia (UnB), DF (Brazil); Grossi-de-Sa, M.F. [Universidade Catolica de Brasilia, DF (Brazil)

2008-07-01

Full text: Bacillus thuringiensis (Bt) is a spore forming bacteria, which produces Cry proteins toxic towards several insect orders. Bt S 811 strain produces at least three Cry toxins: Cry1Ab, Cry1Ia12, and Cry8, and shown toxicity to insects from Coleoptera order. In order to characterize the production of theses toxins, and check its activity against Boll weevil larvae, proteic extracts from Bt cells and supernatant proteins from the bacterial culture, were obtained at different stages of cell cycle; 8, 16, 24, and 32 hours after inoculation (HAI). Proteins from 32 HAI of the supernatant, and 8 HAI of the cellular fractions, shown highest activity towards the Boll weevil larvae. Western blotting assays using anti-Cry8 and anti-Cry1I were carried out to analyse these toxins in the Bt proteic extracts. The existence of a Cry8 was detected at 8 HAI in the cellular fraction, what allow associate this molecule with the toxicity of this fraction. However, toxicity observed at 32 HAI in the supernatant fraction, was not possible to be associated with Cry8 or Cry1Ia toxins, indicating that there are another protein(s) responsible for the toxicity. A protein homo log to Cry1Ab was identified by 'Peptide Mass Fingerprint' at 32 HAI of the supernatant fraction and a chitin binding protein was identified by 2DE/MS/MS in this same stage and chitinolitic activity was also observed by enzymatic assay. All our data suggest a possible synergism between Cry toxins and a chitinase in the activity of this strain towards Boll weevil.

Estimating legume N-2 fixation in grass-clover mixtures of a grazed organic cropping system using two N-15 methods

DEFF Research Database (Denmark)

Vinther, F.P.; Jensen, E.S.

2000-01-01

The input of Nitrogen (N) through symbiotic N-2 fixation (SNF) in grass-clover mixtures was determined in an organic cropping. system for grazing during 3 years. The mixture of perennial ryegrass (Lolium perenne L.) and white clover (Trifolium repens L.) was established by undersowing in spring...... barley (Hordeum vulgare L.) and maintained subsequently for two production years. Dinitrogen fixation was determined using the N-15 isotope dilution techniques and two labelling procedures. Using either pre-labelling of the soil with immobilisation of the N-15 by addition of a carbon source before...

Transfection of cultured cells of the cotton boll weevil, Anthonomus grandis, with a heat-shock-promoter-chloramphenicol-acetyltransferase construct.

Science.gov (United States)

Stiles, B; Heilmann, J; Sparks, R B; Santoso, A; Leopold, R A

1992-01-01

Expression of heat shock proteins (hsp) in the BRL-AG-3C cell line from the cotton boll weevil was examined. It was determined that the maximal expression of endogenous hsp occurred at 41 degrees C. Various transfection methods were then compared using this cell line in conjunction with a transiently expressed bacterial gene marker (chloramphenicol acetyltransferase) which was under the control of the Drosophila hsp 70 gene promoter. The cationic lipid preparation Lipofectin was found to be very efficient at transfecting the boll weevil cells. Polylysine and 20-hydroxyecdysone-conjugated polylysine were moderately effective, whereas polybrene and electroporation, under the conditions reported herein, were ineffective at transfecting this cell line.

New initiatives for managment of red palm weevil threats to historical Arabian date palms

Science.gov (United States)

The date palm is an important part of the religious, cultural, and economic heritage of the Arabian Peninsula. This heritage is threatened by the recent invasion of the red palm weevil(RPW) from Southeast Asia. In Saudi Arabia, a national campaign for control of RPW by containment/destruction of inf...

Effects of insecticides and defoliants applied alone and in combination for control of overwintering boll weevil (Anthonomus grandis; Coleoptera: Curculionidae)--laboratory and field studies.

Science.gov (United States)

Greenberg, Shoil M; Sappington, Thomas W; Elzen, Gary W; Norman, John W; Sparks, Alton N

2004-09-01

In laboratory, greenhouse and field tests, we determined the effects of combining full rates of the defoliants tribufos and thidiazuron and the herbicide thifensulfuron-methyl with half rates of the insecticides lambda-cyhalothrin or azinphos-methyl, and the combination of tribufos and thidiazuron, both in half rates, on mortality of the boll weevil, Anthonomus grandis grandis Boheman and on the quality of defoliation. Tribufos, 0.47 kg ha(-1) and tribufos, 0.235 kg ha(-1) + thidiazuron, 0.125 kg ha(-1) exhibited a slightly toxic effect to boll weevil, while tribufos, 0.47 kg ha(-1) + lambda-cyhalothrin, 0.019 kg ha(-1), tribufos, 0.47 kg ha(-1) + azinphos-methyl, 0.14 kg ha(-1), and tribufos, 0.235 kg ha(-1) + thidiazuron, 0.125 kg ha(-1) + azinphos-methyl, 0.14 kg ha(-l), provided control of boll weevil as good as or better than full-rate azinphos-methyl or lambda-cyhalothrin alone owing to synergistic effects. Thidiazuron or thifensulfuron-methyl alone or in combination with insecticides did not affect boll weevil mortality. Treatment with tribufos + thidiazuron, both at half rate, significantly increased defoliation compared to full rates of tribufos or thidiazuron alone, and provided adequate defoliation for approximately the same cost per hectare.

Determination of toxicity limiting values of Zn, Cu, and Pb for oat and red clover

Energy Technology Data Exchange (ETDEWEB)

Hodenberg, A V; Finck, A

1975-01-01

Toxicity limiting values of Zn, Cu and Pb are determined in order to investigate the causes of growth damages in certain fields. Since the true toxicity limit is difficult to estimate, a somewhat higher content is called the toxicity limiting value resulting after the subtraction of a significant yield difference. The pot experiments with increasing fertilization of Zn, Cu and Pb in soil cultures gave the following results. For Zn, the toxicity limit is 410 ppm in oats at the beginning of tilling. In red clover six weeks of age, it is only 290 ppm of Zn and therefore much lower. For Cu, the toxicity limit is 20 ppm in oats at the beginning of tilling and 18 ppm in six weeks old red clover. For Pb, a toxic effect could be observed above 50 ppm, but this does not seem to be the true limit because of disturbing salt effects.

Semiochemicals from herbivory induced cotton plants enhance the foraging behavior of the cotton boll weevil, Anthonomus grandis.

Science.gov (United States)

Magalhães, D M; Borges, M; Laumann, R A; Sujii, E R; Mayon, P; Caulfield, J C; Midega, C A O; Khan, Z R; Pickett, J A; Birkett, M A; Blassioli-Moraes, M C

2012-12-01

The boll weevil, Anthonomus grandis, has been monitored through deployment of traps baited with aggregation pheromone components. However, field studies have shown that the number of insects caught in these traps is significantly reduced during cotton squaring, suggesting that volatiles produced by plants at this phenological stage may be involved in attraction. Here, we evaluated the chemical profile of volatile organic compounds (VOCs) emitted by undamaged or damaged cotton plants at different phenological stages, under different infestation conditions, and determined the attractiveness of these VOCs to adults of A. grandis. In addition, we investigated whether or not VOCs released by cotton plants enhanced the attractiveness of the aggregation pheromone emitted by male boll weevils. Behavioral responses of A. grandis to VOCs from conspecific-damaged, heterospecific-damaged (Spodoptera frugiperda and Euschistus heros) and undamaged cotton plants, at different phenological stages, were assessed in Y-tube olfactometers. The results showed that volatiles emitted from reproductive cotton plants damaged by conspecifics were attractive to adults boll weevils, whereas volatiles induced by heterospecific herbivores were not as attractive. Additionally, addition of boll weevil-induced volatiles from reproductive cotton plants to aggregation pheromone gave increased attraction, relative to the pheromone alone. The VOC profiles of undamaged and mechanically damaged cotton plants, in both phenological stages, were not different. Chemical analysis showed that cotton plants produced qualitatively similar volatile profiles regardless of damage type, but the quantities produced differed according to the plant's phenological stage and the herbivore species. Notably, vegetative cotton plants released higher amounts of VOCs compared to reproductive plants. At both stages, the highest rate of VOC release was observed in A. grandis-damaged plants. Results show that A. grandis uses

Effects of covering highland banana stumps with soil on banana weevil Cosmopolites sordidus (Coleoptera: Curculionidae) oviposition

NARCIS (Netherlands)

Masanza, M.; Gold, C.S.; Huis, van A.; Ragama, P.E.

2005-01-01

The effect of covering post-harvest banana stumps with soil on banana weevil Cosmopolites sordidus (Germar) oviposition levels was investigated at three locations, Sendusu, Kawanda Agricultural Research Institute (KARI) and Ntungamo district of southwestern Uganda. In the first experiment

Sexual polyploidization in red clover Poliploidização sexual em trevo vermelho

Directory of Open Access Journals (Sweden)

Carine Simioni

2006-02-01

Full Text Available Because sexual polyploidization broadens genetic basis and supply plant breeders with more variability for the selection process, it can be useful in red clover breeding. This paper reports results of three crossing cycles, starting from a parental generation of tetraploid red clover plants (female parent, and diploids from the Quiñiqueli cultivar, selected for production of more than 1% of giant pollen grains (male parent aiming to obtain tetraploid plants to be used in red clover breeding programs. Crosses in the next generations were performed by mutual cross-pollinations. Chromosome number chimerism and high pollen sterility were detected in F1, F2 and F3, but there was a trend towards increasing seed production and seed viability along the generations, probably due to successful competition between fertile and sterile gametes. The identification of fertile triploids, as well as their recurrent formation along the generations, indicates that triploid block is not complete in red clover, and that triploids may be successfully used as a bridge for the production of sexual polyploids.Porque a poliploidização sexual amplia a base genética e proporciona aos melhoristas maior variabilidade para o processo de seleção, ela pode ser uma ferramenta útil ao melhoramento de trevo vermelho. Com o objetivo de obter plantas tetraplóides que possam ser utilizadas em programas de melhoramento de trevo vermelho, este trabalho relata resultados de três ciclos de cruzamentos, partindo de uma população parental de plantas tetraplóides de trevo vermelho, como genitores femininos, e de diplóides da cultivar Quiñiqueli, selecionados para produção de mais de 1% de grãos de pólen gigantes, como genitores masculinos. Nas outras gerações, os cruzamentos foram realizados por polinizações cruzadas mútuas. Quimerismo para número cromossômico e alta esterilidade de pólen foram detectados em F1 , F2 e F3, mas houve uma tendência para aumento da

Biological activity of clovers - free radical scavenging ability and antioxidant action of six Trifolium species.

Science.gov (United States)

Kolodziejczyk-Czepas, Joanna; Nowak, Pawel; Kowalska, Iwona; Stochmal, Anna

2014-10-01

Clovers were chosen on the basis of traditional medicine recommendations, agricultural value, or available information on their promising chemical profiles. This study evaluates and compares free radical scavenging and antioxidant properties of six clover species: Trifolium alexandrinum L. (Leguminosae), Trifolium fragiferum L., Trifolium hybridum L., Trifolium incarnatum L., Trifolium resupinatum var. majus Boiss., and Trifolium resupinatum var. resupinatum L. Free radical scavenging activity of the extracts (1.5-50 µg/ml) was estimated by reduction of 1,1-diphenyl-2-picrylhydrazyl (DPPH(•)) and 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic) acid (ABTS(•)) radicals. The Trifolium extract effects on total antioxidant capacity of blood plasma were determined by the reduction of ABTS(•+) and DPPH(•) radicals, as well as with the use of the ferric reducing ability of plasma (FRAP) assay. The UPLC analysis of chemical profiles of the examined extracts showed the presence of three or four groups of phenolic substances, including phenolic acids, clovamides, isoflavones, and other flavonoids. The measurements of free radical scavenging and ferric reducing ability of the examined clover extracts revealed the strongest effect for T. alexandrinum. Furthermore, antioxidant activity assays in human plasma have shown protective effects of all extracts against peroxynitrite-induced reduction of total antioxidant capacity. Trifolium plants may be a rich source of bioactive substances with antioxidant properties. The examined extracts displayed free radical scavenging action and partly protected blood plasma against peroxynitrite-induced oxidative stress; however, the beneficial effects of T. alexandrinum and T. incarnatum seem to be slightly higher.

Effect of aditive supplementation to ensiled red clover on voluntary intake, digestibility and N balance

Directory of Open Access Journals (Sweden)

Marina Vranić

2009-06-01

Full Text Available The objective of this study was to determine effect of additive supplementation to red clover silage on ad libitum intake of fresh silage and dry matter (DM, in vivo digestibility of DM, organic matter (OM, OM in DM (D-value, crude protein (CP and nitrogen (N balance. Red clover was harvested at 60% bloom stage. It was ensiled into round bales without an additive (CD and with an additive supplementation (CDA in the amount of 2 L t-1 fresh material. Statistically lower (P<0.001 DM content was recorded in CD (405 g kg-1 fresh sample in comparison with CDA (665 g ST kg-1 fresh sample. Statistically higher CP content (P<0.001 was recorded in CD (127 g kg-1 ST in comparison with CDA (110 g SP kg-1 ST. CD had lower pH (P<0.001 (4.9 in comparison with CDA (5.2. No differences were recorded in NH3 between treatments. Ad libitum intake of fresh silage and silage DM was higher (P<0.001 and P<0.01, respectively in CD in comparison with CDA. Digestibility of DM, OM, CP, D-value and N balance were not different between treatments. It was concluded that the positive effect of additive supplementation to red clover silage on chemical composition, ad libitum intake, digestibility and N balance was not recorded due to applied ensiling technology as additive can improve feeding value of roughage, but it is not a replacement for good management practices.

Data on the abundance of the banana weevil Cosmopolites sordidus and of the earwig Euborellia caraibea in bare soil and cover crop plots.

Science.gov (United States)

Carval, Dominique; Resmond, Rémi; Achard, Raphaël; Tixier, Philippe

2016-06-01

The data presented in this article are related to the research article entitled "Cover cropping reduces the abundance of the banana weevil Cosmopolites sordidus but does not reduce its damage to the banana plants" (Carval et al., in press) [1]. This article describes how the abundance of the banana weevil, Cosmopolites sordidus, and the abundance of the earwig Euborellia caraibea were affected by the addition of a cover crop. The field data set is made publicly available to enable critical or extended analyzes.

Data on the abundance of the banana weevil Cosmopolites sordidus and of the earwig Euborellia caraibea in bare soil and cover crop plots

OpenAIRE

Carval, Dominique; Resmond, Rémi; Achard, Raphaël; Tixier, Philippe

2016-01-01

The data presented in this article are related to the research article entitled “Cover cropping reduces the abundance of the banana weevil Cosmopolites sordidus but does not reduce its damage to the banana plants” (Carval et al., in press) [1]. This article describes how the abundance of the banana weevil, Cosmopolites sordidus, and the abundance of the earwig Euborellia caraibea were affected by the addition of a cover crop. The field data set is made publicly available to enable critical or...

Effects of gamma irradiation on some major elements and mating competitiveness of the red Palm Weevil, Rhynchophorus Ferrugineus (OLIVIER), Coleoptera : Curculionidae

International Nuclear Information System (INIS)

Mohamed, H.F.; EL-Naggar, S.M.; EL-Kkoly, E.M.S.

2006-01-01

In the present study, effects of three gamma doses (5, 10 and 15 Gray) applied to adult male and female weevils of the red palm weevil, Rhynchophorus ferrugineus (Olivier), were investigated. The concentration levels of sodium, potassium, calcium and phosphorous were determined in the haemolymph treated and untreated F1 progeny (males or females) at the 4th instar larvae descendants from irradiated parents male and female weevils. Results indicated that gamma irradiation might have an effect on most investigated elements. No clear relationship could be detected among the applied doses and effect on the level of any of the studied elements. Male mating competitiveness was determined from the egg infertility resulting from F1 males originating from irradiated parental male weevils confined in various ratios with unirradiated adults. Studies comparing mating performance of irradiated males with that of normal males revealed that the mating competitiveness of the irradiated males was increased as the ratio of irradiated to unirradiated males increased from 1 : 1 to 3 : 1 , except at the lesser dose 5 Gy .The results also showed that the infertility was increased as the ratios increased except at the dose rate 10 Gy . The irradiated males were not fully competitive with normal males at the dose 5 Gy among the two ratios 1 : 1 and 3 : 1 and also among the ratio 1:1 at the doses 10 and 15 Gy. The irradiated males were fully competitive with normal males at the doses 10 and 15 Gy among the ratio 3 : 1

Otiorhynchus spp. (Coleoptera: Curculionidae) as pests in horticulture: genetics and management options with entomopathogenic fungi

OpenAIRE

Hirsch, Jacqueline

2012-01-01

Worldwide, weevils of the genus Otiorhynchus (Coleoptera: Curculionidae) cause damage with detrimental economic effects to many horticultural crops due to the root feeding of their larvae as well as foliage feeding of their adults. Aside from the black vine weevil Otiorhynchus sulcatus, which is the best-known pest within this genus, numerous other Otiorhynchus species have been increasingly recognized as pests in recent years. Nocturnal adult weevils and soil-inhibiting larvae are in princip...

Roots of symptom-free leguminous cover crop and living mulch species harbor diverse Fusarium communities that show highly variable aggressiveness on pea (Pisum sativum).

Science.gov (United States)

Šišić, Adnan; Baćanović-Šišić, Jelena; Karlovsky, Petr; Wittwer, Raphaël; Walder, Florian; Campiglia, Enio; Radicetti, Emanuele; Friberg, Hanna; Baresel, Jörg Peter; Finckh, Maria R

2018-01-01

Leguminous cover crop and living mulch species show not only great potential for providing multiple beneficial services to agro-ecosystems, but may also present pathological risks for other crops in rotations through shared pathogens, especially those of the genus Fusarium. Disease severity on roots of subterranean clover, white clover, winter and summer vetch grown as cover crop and living mulch species across five European sites as well as the frequency, distribution and aggressiveness to pea of Fusarium spp. recovered from the roots were assessed in 2013 and 2014. Disease symptoms were very low at all sites. Nevertheless, out of 1480 asymptomatic roots, 670 isolates of 14 Fusarium spp. were recovered. The most frequently isolated species in both years from all hosts were F. oxysporum and F. avenaceum accounting for 69% of total isolation percentage. They were common at the Swiss, Italian and German sites, whereas at the Swedish site F. oxysporum dominated and F. avenaceum occurred only rarely. The agressiveness and effect on pea biomass were tested in greenhouse assays for 72 isolates of six Fusarium species. Isolates of F. avenaceum caused severe root rot symptoms with mean severity index (DI) of 82 and 74% mean biomass reduction compared to the non-inoculated control. Fusarium oxysporum and F. solani isolates were higly variable in agressiveness and their impact on pea biomass. DI varied between 15 and 50 and biomass changes relative to the non-inoculated control -40% to +10%. Isolates of F. tricinctum, F. acuminatum and F. equiseti were non to weakly agressive often enhancing pea biomass. This study shows that some of the major pea pathogens are characterized by high ecological plasticity and have the ability to endophytically colonize the hosts studied that thus may serve as inoculum reservoir for susceptible main legume grain crops such as pea.

Roots of symptom-free leguminous cover crop and living mulch species harbor diverse Fusarium communities that show highly variable aggressiveness on pea (Pisum sativum.

Directory of Open Access Journals (Sweden)

Adnan Šišić

Full Text Available Leguminous cover crop and living mulch species show not only great potential for providing multiple beneficial services to agro-ecosystems, but may also present pathological risks for other crops in rotations through shared pathogens, especially those of the genus Fusarium. Disease severity on roots of subterranean clover, white clover, winter and summer vetch grown as cover crop and living mulch species across five European sites as well as the frequency, distribution and aggressiveness to pea of Fusarium spp. recovered from the roots were assessed in 2013 and 2014. Disease symptoms were very low at all sites. Nevertheless, out of 1480 asymptomatic roots, 670 isolates of 14 Fusarium spp. were recovered. The most frequently isolated species in both years from all hosts were F. oxysporum and F. avenaceum accounting for 69% of total isolation percentage. They were common at the Swiss, Italian and German sites, whereas at the Swedish site F. oxysporum dominated and F. avenaceum occurred only rarely. The agressiveness and effect on pea biomass were tested in greenhouse assays for 72 isolates of six Fusarium species. Isolates of F. avenaceum caused severe root rot symptoms with mean severity index (DI of 82 and 74% mean biomass reduction compared to the non-inoculated control. Fusarium oxysporum and F. solani isolates were higly variable in agressiveness and their impact on pea biomass. DI varied between 15 and 50 and biomass changes relative to the non-inoculated control -40% to +10%. Isolates of F. tricinctum, F. acuminatum and F. equiseti were non to weakly agressive often enhancing pea biomass. This study shows that some of the major pea pathogens are characterized by high ecological plasticity and have the ability to endophytically colonize the hosts studied that thus may serve as inoculum reservoir for susceptible main legume grain crops such as pea.

Roots of symptom-free leguminous cover crop and living mulch species harbor diverse Fusarium communities that show highly variable aggressiveness on pea (Pisum sativum)

Science.gov (United States)

Baćanović-Šišić, Jelena; Karlovsky, Petr; Wittwer, Raphaël; Walder, Florian; Campiglia, Enio; Radicetti, Emanuele; Friberg, Hanna; Baresel, Jörg Peter; Finckh, Maria R.

2018-01-01

Leguminous cover crop and living mulch species show not only great potential for providing multiple beneficial services to agro-ecosystems, but may also present pathological risks for other crops in rotations through shared pathogens, especially those of the genus Fusarium. Disease severity on roots of subterranean clover, white clover, winter and summer vetch grown as cover crop and living mulch species across five European sites as well as the frequency, distribution and aggressiveness to pea of Fusarium spp. recovered from the roots were assessed in 2013 and 2014. Disease symptoms were very low at all sites. Nevertheless, out of 1480 asymptomatic roots, 670 isolates of 14 Fusarium spp. were recovered. The most frequently isolated species in both years from all hosts were F. oxysporum and F. avenaceum accounting for 69% of total isolation percentage. They were common at the Swiss, Italian and German sites, whereas at the Swedish site F. oxysporum dominated and F. avenaceum occurred only rarely. The agressiveness and effect on pea biomass were tested in greenhouse assays for 72 isolates of six Fusarium species. Isolates of F. avenaceum caused severe root rot symptoms with mean severity index (DI) of 82 and 74% mean biomass reduction compared to the non-inoculated control. Fusarium oxysporum and F. solani isolates were higly variable in agressiveness and their impact on pea biomass. DI varied between 15 and 50 and biomass changes relative to the non-inoculated control -40% to +10%. Isolates of F. tricinctum, F. acuminatum and F. equiseti were non to weakly agressive often enhancing pea biomass. This study shows that some of the major pea pathogens are characterized by high ecological plasticity and have the ability to endophytically colonize the hosts studied that thus may serve as inoculum reservoir for susceptible main legume grain crops such as pea. PMID:29444142

Olfaction in the boll weevil,Anthonomus grandis Boh. (Coleoptera: Curculionidae): Electroantennogram studies.

Science.gov (United States)

Dickens, J C

1984-12-01

Electroantennogram (EAG) techniques were utilized to measure the antennal olfactory responsiveness of adult boll weevils,Anthonomus grandis Boh. (Coleoptera: Curculionidae), to 38 odorants, including both insect and host plant (Gossypium hirsutum L.) volatiles. EAGs of both sexes were indicative of at least two receptor populations: one receptor population primarily responsive to pheromone components and related compounds, the other receptor population primarily responsive to plant odors. Similar responses to male aggregation pheromone components (i.e., compounds I, II, and III + IV) were obtained from both sexes, but females were slightly more sensitive to I. Both sexes were highly responsive to components of the "green leaf volatile complex," especially the six-carbon saturated and monounsaturated primary alcohols. Heptanal was the most active aldehyde tested. More acceptors responded to oxygenated monoterpenes than to monoterpene hydrocarbons. β-Bisabolol, the major volatile of cotton, was the most active sesquiterpene. In general, males, which are responsible for host selection and pheromone production, were more sensitive to plant odors than were females. In fact, males were as sensitive to β-bisabolol and heptanal as to aggregation pheromone components. Electrophysiological data are discussed with regard to the role of insect and host plant volatiles in host selection and aggregation behavior of the boll weevil.

Data on the abundance of the banana weevil Cosmopolites sordidus and of the earwig Euborellia caraibea in bare soil and cover crop plots

Directory of Open Access Journals (Sweden)

Dominique Carval

2016-06-01

Full Text Available The data presented in this article are related to the research article entitled “Cover cropping reduces the abundance of the banana weevil Cosmopolites sordidus but does not reduce its damage to the banana plants” (Carval et al., in press [1]. This article describes how the abundance of the banana weevil, Cosmopolites sordidus, and the abundance of the earwig Euborellia caraibea were affected by the addition of a cover crop. The field data set is made publicly available to enable critical or extended analyzes.

Genetic variability and resistance of cultivars of cowpea [Vigna unguiculata (L.) Walp] to cowpea weevil (Callosobruchus maculatus Fabr.).

Science.gov (United States)

Vila Nova, M X; Leite, N G A; Houllou, L M; Medeiros, L V; Lira Neto, A C; Hsie, B S; Borges-Paluch, L R; Santos, B S; Araujo, C S F; Rocha, A A; Costa, A F

2014-03-31

The cowpea weevil (Callosobruchus maculatus Fabr.) is the most destructive pest of the cowpea bean; it reduces seed quality. To control this pest, resistance testing combined with genetic analysis using molecular markers has been widely applied in research. Among the markers that show reliable results, the inter-simple sequence repeats (ISSRs) (microsatellites) are noteworthy. This study was performed to evaluate the resistance of 27 cultivars of cowpea bean to cowpea weevil. We tested the resistance related to the genetic variability of these cultivars using ISSR markers. To analyze the resistance of cultivars to weevil, a completely randomized test design with 4 replicates and 27 treatments was adopted. Five pairs of the insect were placed in 30 grains per replicate. Analysis of variance showed that the number of eggs and emerged insects were significantly different in the treatments, and the means were compared by statistical tests. The analysis of the large genetic variability in all cultivars resulted in the formation of different groups. The test of resistance showed that the cultivar Inhuma was the most sensitive to both number of eggs and number of emerged adults, while the TE96-290-12-G and MNC99-537-F4 (BRS Tumucumaque) cultivars were the least sensitive to the number of eggs and the number of emerged insects, respectively.

ECOLOGICAL-FAUNISTIC AND ZOOGEOGRAPHICAL CHARACTERISTIC OF BEETLE-WEEVILS OF ISLAND CHECHEN OF THE CASPIAN SEA

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Y. G. Arsanov

2014-01-01

Full Text Available Aim. Ecological-faunistic investigations of island Chechen are great interest for understanding the law of formation of island biotas and reconstruction of zoogeological history of the Caspian Sea. Faunistic investigations of islands and coastal areas , habitats and others chorologic aspects illuminate the ways of their probable settlement,explains the paradoxes of propagation of some species. Study of relationships with host plants appear the crucial stage of ecological-faunistic investigathions of the weevils.Location. Materials of the work were expeditionary duties of the authors, as well as staff and the students of ecologo-geografical faculty of Dagistan State University and the Institute for Applied Ecology ( Makhachkala from 2009 to 2013 year for the island Chechen.Methods. Charges were made with the help of light traps, soil traps, including trap, enhanced light source .Geografpical coordinates of all locations were recorded using GPS- navigator: T1 - 43°57’58” N 47°38’35” E; T2 - 43°58’17” N 47°42’55”; T3 - 43°59’08” N 47°44’39” E; T4 - 43°57’27” N 47°45’05” E; T5 - 43°58’11” N47°38’46” E.Results. As a result of studies were set the species composition of the faun of the beetle-weevils of the island Chechen, the analyses of the distribution of species by locality; mounted forage plants of the beetles and quantitative distribution of the beetls for families forage plants; conduct the zoogeographical analysis of studied fauna.Main conclusions. The studies on the island of Chechen were collected 187 specimens belonging to 16 species and 14 geniuse; the most common type was Coniatus splendidulus. The food base of the weevil beetles in the island of Chechen are 10 plant families,thelargest number of species focused on Chenopodiаceae, then followed Polygonaceae, Poaceae, Fabaceae. Analysis of fauna habitats of the beetle- weevils of the island Chechen allowed to allocate 7

Knock-down of transcript abundance of a family of Kunitz proteinase inhibitor genes in white clover (Trifolium repens) reveals a redundancy and diversity of gene function.

Science.gov (United States)

Islam, Afsana; Leung, Susanna; Burgess, Elisabeth P J; Laing, William A; Richardson, Kim A; Hofmann, Rainer W; Dijkwel, Paul P; McManus, Michael T

2015-12-01

The transcriptional regulation of four phylogenetically distinct members of a family of Kunitz proteinase inhibitor (KPI) genes isolated from white clover (Trifolium repens; designated Tr-KPI1, Tr-KPI2, Tr-KPI4 and Tr-KPI5) has been investigated to determine their wider functional role. The four genes displayed differential transcription during seed germination, and in different tissues of the mature plant, and transcription was also ontogenetically regulated. Heterologous over-expression of Tr-KPI1, Tr-KPI2, Tr-KPI4 and Tr-KPI5 in Nicotiana tabacum retarded larval growth of the herbivore Spodoptera litura, and an increase in the transcription of the pathogenesis-related genes PR1 and PR4 was observed in the Tr-KPI1 and Tr-KPI4 over-expressing lines. RNA interference (RNAi) knock-down lines in white clover displayed significantly altered vegetative growth phenotypes with inhibition of shoot growth and a stimulation of root growth, while knock-down of Tr-KPI1, Tr-KPI2 and Tr-KPI5 transcript abundance also retarded larval growth of S. litura. Examination of these RNAi lines revealed constitutive stress-associated phenotypes as well as altered transcription of cellular signalling genes. These results reveal a functional redundancy across members of the KPI gene family. Further, the regulation of transcription of at least one member of the family, Tr-KPI2, may occupy a central role in the maintenance of a cellular homeostasis. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

Host plant odours enhance the responses of adult banana weevil to the synthetic aggregation pheromone Cosmolure+

NARCIS (Netherlands)

Tinzaara, W.; Gold, C.S.; Dicke, M.; Huis, van A.; Ragama, P.E.

2007-01-01

Attraction of adult banana weevil, Cosmopolites sordidus to volatiles from banana pseudostem tissue and the synthetic pheromone Cosmolure+ presented singly or in combination, was studied in the laboratory and in the field. Olfactometric studies in the laboratory showed that 50 g of fermented banana

Performance comparison for modes of operation and suppression cases of the clover detector

International Nuclear Information System (INIS)

Kshetri, R

2014-01-01

Peak-to-total ratios have been extracted for a segmented clover detector for various modes of operation and suppression cases. Based on absorption and scattering of gamma-rays, a formalism has been presented for quantifying the advantages of using addback mode and active suppression. Further investigations have been performed to find if the reduction of background counts is caused more by active suppression or by addback process

A new light on the evolution and propagation of prehistoric grain pests: the world's oldest maize weevils found in Jomon Potteries, Japan.

Science.gov (United States)

Obata, Hiroki; Manabe, Aya; Nakamura, Naoko; Onishi, Tomokazu; Senba, Yasuko

2011-03-29

Three Sitophilus species (S. granarius L., S. oryzae L., and S. zeamais Mots.) are closely related based on DNA analysis of their endosymbionts. All are seed parasites of cereal crops and important economic pest species in stored grain. The Sitophilus species that currently exist, including these three species, are generally believed to be endemic to Asia's forested areas, suggesting that the first infestations of stored grain must have taken place near the forested mountains of southwestern Asia. Previous archaeological data and historical records suggest that the three species may have been diffused by the spread of Neolithic agriculture, but this hypothesis has only been established for granary weevils in European and southwestern Asian archaeological records. There was little archeological evidence for grain pests in East Asia before the discovery of maize weevil impressions in Jomon pottery in 2004 using the "impression replica" method. Our research on Jomon agriculture based on seed and insect impressions in pottery continued to seek additional evidence. In 2010, we discovered older weevil impressions in Jomon pottery dating to ca. 10 500 BP. These specimens are the oldest harmful insects in the world discovered at archaeological sites. Our results provide evidence of harmful insects living in the villages from the Earliest Jomon, when no cereals were cultivated. This suggests we must reconsider previous scenarios for the evolution and propagation of grain pest weevils, especially in eastern Asia. Although details of their biology or the foods they infested remain unclear, we hope future interdisciplinary collaborations among geneticists, entomologists, and archaeologists will provide the missing details.

A new light on the evolution and propagation of prehistoric grain pests: the world's oldest maize weevils found in Jomon Potteries, Japan.

Directory of Open Access Journals (Sweden)

Hiroki Obata

Full Text Available Three Sitophilus species (S. granarius L., S. oryzae L., and S. zeamais Mots. are closely related based on DNA analysis of their endosymbionts. All are seed parasites of cereal crops and important economic pest species in stored grain. The Sitophilus species that currently exist, including these three species, are generally believed to be endemic to Asia's forested areas, suggesting that the first infestations of stored grain must have taken place near the forested mountains of southwestern Asia. Previous archaeological data and historical records suggest that the three species may have been diffused by the spread of Neolithic agriculture, but this hypothesis has only been established for granary weevils in European and southwestern Asian archaeological records. There was little archeological evidence for grain pests in East Asia before the discovery of maize weevil impressions in Jomon pottery in 2004 using the "impression replica" method. Our research on Jomon agriculture based on seed and insect impressions in pottery continued to seek additional evidence. In 2010, we discovered older weevil impressions in Jomon pottery dating to ca. 10 500 BP. These specimens are the oldest harmful insects in the world discovered at archaeological sites. Our results provide evidence of harmful insects living in the villages from the Earliest Jomon, when no cereals were cultivated. This suggests we must reconsider previous scenarios for the evolution and propagation of grain pest weevils, especially in eastern Asia. Although details of their biology or the foods they infested remain unclear, we hope future interdisciplinary collaborations among geneticists, entomologists, and archaeologists will provide the missing details.

Towards an optimal sampling strategy for assessing genetic variation within and among white clover (Trifolium repens L. cultivars using AFLP

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Khosro Mehdi Khanlou

2011-01-01

Full Text Available Cost reduction in plant breeding and conservation programs depends largely on correctly defining the minimal sample size required for the trustworthy assessment of intra- and inter-cultivar genetic variation. White clover, an important pasture legume, was chosen for studying this aspect. In clonal plants, such as the aforementioned, an appropriate sampling scheme eliminates the redundant analysis of identical genotypes. The aim was to define an optimal sampling strategy, i.e., the minimum sample size and appropriate sampling scheme for white clover cultivars, by using AFLP data (283 loci from three popular types. A grid-based sampling scheme, with an interplant distance of at least 40 cm, was sufficient to avoid any excess in replicates. Simulations revealed that the number of samples substantially influenced genetic diversity parameters. When using less than 15 per cultivar, the expected heterozygosity (He and Shannon diversity index (I were greatly underestimated, whereas with 20, more than 95% of total intra-cultivar genetic variation was covered. Based on AMOVA, a 20-cultivar sample was apparently sufficient to accurately quantify individual genetic structuring. The recommended sampling strategy facilitates the efficient characterization of diversity in white clover, for both conservation and exploitation.

Nucleon form factors and structure functions from Nf=2 Clover fermions

International Nuclear Information System (INIS)

Collins, S.; Goeckeler, M.; Haegler, P.

2010-12-01

We give an update on our ongoing efforts to compute the nucleon's form factors and moments of structure functions using N f =2 flavours of non-perturbatively improved Clover fermions. We focus on new results obtained on gauge configurations where the pseudo-scalar meson mass is in the range of 170-270 MeV. We compare our results with various estimates obtained from chiral effective theories since we have some overlap with the quark mass region where results from such theories are believed to be applicable. (orig.)

Effects of Rhizobium inoculation on Trifolium resupinatum antioxidant system under sulfur dioxide pollution

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Ladan Bayat

2014-01-01

Full Text Available Introduction: Plant growth stimulating rhizobacteria are beneficial bacteria that can cause resistance to various stresses in plants. One of these stresses is SO2 air pollution. SO2 is known as a strong damaging air pollutant that limits growth of plants. The aim of this study is evaluation of the effects of bacterial inoculation with native and standard Rhizobium on Persian clover root growth and antioxidants activity and capacity under air SO2 pollution. Materials and methods: In this study, 31 days plants (no-inoculated and inoculated with two strains of Rhizobium exposed to the different concentrations of SO2 (0 as a control, 0.5, 1, 1.5 and 2 ppm for 5 consecutive days and 2 hours per day. Results: Results showed different concentrations of SO2 had a significant effect on Persian clover root weight and antioxidant system. Increasing SO2 stress decreased root fresh and dry weight and antioxidant capacities (IC50 and increased antioxidant activities (I% of Persian clover leaves significantly in comparison to the control plants (under 0 ppm and increased SOD, CAT and GPX activity. Inoculation of Persian clover plants with native and standard Rhizobium increased root weight and did not show a significant effect on antioxidants activity and capacity, but interaction between Rhizobium inoculation and SO2 treatment reduced significantly the stress effects of high concentration of SO2 on root growth and antioxidants activity and capacity. In fact, level of this change of root growth and antioxidant system under SO2 pollution stress in inoculated plants was lower than in the non-inoculated plants. Discussion and conclusion: As a result, an increase in SO2 concentration caused a decrease in root weight, increase in antioxidants activity and capacity of Persian clover. Inoculation with Rhizobium strains could alleviate the effect of SO2 pollution on antioxidant system by effects on root growth.

Environmental life cycle assessments of producing maize, grass-clover, ryegrass and winter wheat straw for biorefinery

DEFF Research Database (Denmark)

Parajuli, Ranjan; Kristensen, Ib Sillebak; Knudsen, Marie Trydeman

2017-01-01

The aim of this study is to assess the potential environmental impacts of producing maize, grass-clover, ryegrass, and straw from winter wheat as biomass feedstocks for biorefinery. The Life Cycle Assessment (LCA) method included the following impact categories: Global Warming Potential (GWP100),...

Optimization of a protocol for direct organogenesis of red clover (Trifolium pratense L. meristems for breeding purposes

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JUAN C CARRILLO

2004-01-01

Full Text Available A series of experiments were carried out in order to optimize a protocol for the direct organogenesis of Chilean red clover germplasm. A range of cultivars were used to analyze the effect of explant source (crown or stem meristems of vegetative plants, culture media and plant growth regulators. Our findings showed that stem meristems were easier to obtain, presented lower levels of contamination and a better development than crown meristems. The L2 medium showed better results than B5 and MS media for the cultivars and experimental lines studied. L2 medium supplemented with 0.003 mg/l of 4-amino-3,5,6-trichloropicolinic acid and 1.0 mg/l of 6-benzylaminopurine gave consistently better results and will be applied in our breeding program to propagate, maintain and eliminate viruses from elite red clover clones.

Cleaning the Soil from Zinc Using Red Clovers “Arimaičiai”

OpenAIRE

Audronė Mikalajūnė; Giedrė Jasulaitytė

2011-01-01

Zinc as a nutrition element is required to plants in small quantities to maintain normal functions of metabolism mechanisms. Our work analyses the efficiency of red clovers “Arimaičiai” for cleaning zinc from the soil contaminated with zinc under laboratory conditions. Seeds were sown in three differently polluted soils: clean soil, once contaminated with zinc and periodically contaminated with zinc soil. Zinc concentration in one time contaminated soil was 45 mg/kg. After 6 months of phytore...

Biologically fixed N2 as a source for N2O production in a grass–clover mixture, measured by 15N2 (erratum i vol. 74 p. 203)

DEFF Research Database (Denmark)

Carter, Mette Sustmann; Ambus, P.

2006-01-01

The contribution of biologically fixed dinitrogen (N-2) to the nitrous oxide (N2O) production in grasslands is unknown. To assess the contribution of recently fixed N-2 as a source of N2O and the transfer of fixed N from clover to companion grass, mixtures of white clover and perennial ryegrass...

Use of inorganic and organic compounds as decontaminates for cobalt T-60 and cesium-134 by clover plant grown on Inshas Sandy soil

International Nuclear Information System (INIS)

Abdel-Sabour, M.F.; El-naggr, H.A.; Soliman, S.M.

1994-01-01

Out door lysimeter experiment was carried out to elucidate the effect of four inorganic and three organic salts on 60 Co and 134 Cs uptake and dry matter yield of three cuts of clover in the soil Inshas A new concept was proposed for assessing the difference in capacity of soil to supply radionuclides (i.e. 60 Co and 134 Cs) to plants as affected by applied inorganic or organic compounds. The relation of plant tissues (P c ) Co/IR Cs content with increasing time can be expressed as log (Pc) = A + B log time (T), where A and B the regression. When the same plant species is grown on the same soil differ only in the applied compound (e.g. Fe-EDDHA, Fe-DTPA, Fe-O A C, Fe(Coo)z, A1(OH)3, Ca(H2 P O 4 )2 and Fe 2 O 3 ) the equation will change to, log (P'c) = A + B' log (T) (I). Based on both equations, the relationship between (Pc) becomes; log (P'c) = [(A'B')/(A B + A B ) [ +[1/A'B + A B ) [ log (Pc) (II). The intercept (C) and slope (S) in Eq. (II) were determined among 7 treatments (for either 60 Co or 134 Cs). Then the difference of either Co or Cs accumulation with time between control and any other treatment was evaluated according to (C) and (S) values. The data also that Fe-DTPA is preferred for 60 Co as enhancing compound for plant uptake (for decontamination use); compared with other applied salts; on the other hand, any tested salts did not significantly effect 134 Cs taken by clover. Also, it was found that more than 70% of total cobalt uptake was accumulated in the roots which indicate that Co is less mobile in plants than Cs. 3 figs., 4 tabs

Assessment of Protective Effect of Some Modern Agrochemicals against Ozone-Induced Stress in Sensitive Clover and Tobacco Cultivars.

Science.gov (United States)

Blum, Oleg; Didyk, Nataliya; Pavluchenko, Nataliya; Godzik, Barbara

2011-01-01

Some modern agrochemicals with antioxidant potential were tested for their protective effect against ozone injury using clover and tobacco ozone-sensitive cultivars as model plants subjected to ambient ozone at two sites (Kyiv city in Ukraine and Szarów village in Poland). All used agrochemicals showed partial protective effects against ozone injury on clover and tobacco. Conducted studies confirmed the effectiveness of modern fungicides belonging to strobilurin group as protectants of sensitive crops against ozone damage. The effectiveness of new growth regulators "Emistym C" and "Agrostymulin" was showed for the first time. Out of the studied agrochemicals, fungicide "Strobi" and natural growth regulator "Emistym C" demonstrated the best protective effects. These agrochemicals present promise for further studies of their possible utilization for enhancement of ozone tolerance of sensitive crops.

Effects of soil properties and P fertilizers on trace element uptake of red clover in a pot experiment

International Nuclear Information System (INIS)

Osztoics, E.; Bujtas, K.

1999-01-01

The impacts of superphosphate and Algerian phosphate rock and their various application rates on soil pH and on the availability of trace elements by red clover were studied in a pot experiment on several types of acidic soils from the Carpathian basin. The differences among the soils' original pH and texture, and those differences in soil pH, which resulted from the application of different P forms and rotes were reflected in the Mn, Ni, Al, Co, Sr, Cd and Cr contents of red clover. Plant concentrations of those elements were smaller on the slightly acidic than on the strongly and extremely strongly acidic soils. Elemental concentrations were generally higher when there was less time between two cuts, and decreased in the later cuts. Refs. 11 (author)

Meat goat kids finished on alfalfa, red clover, or orchardgrass pastures: Carcass merit and meat quality

Science.gov (United States)

This experiment was conducted in 2005-2007 to evaluate carcass and meat quality parameters when meat goat kids were finished on alfalfa (Medicago sativa L; ALF); red clover (Trifolium pretense L.; RCG); or orchardgrass (Dactylis glomerata L; OGR) pastures. Final shrunk body weights were similar whe...

Does introduction of clover in an agricultural grassland affect the food base and functional diversity of Collembola?

NARCIS (Netherlands)

Annibale, D' Alessandra; Sechi, Valentina; Larsen, Thomas; Christensen, Søren; Krogh, Paul Henning; Eriksen, Jørgen

2017-01-01

Introduction of legumes (i.e. white clover) in agricultural grasslands is a common practice to improve yields, but how this affects soil fauna populations, particularly mesofauna, is still poorly understood. We investigated taxonomical and functional differences of Collembola communities between

Isolation of Burkholderia cepacia JB12 from lead- and cadmium-contaminated soil and its potential in promoting phytoremediation with tall fescue and red clover.

Science.gov (United States)

Jin, Zhong Min; Sha, Wei; Zhang, Yan Fu; Zhao, Jing; Ji, Hongyang

2013-07-01

Phytoremediation combined with suitable microorganisms and biodegradable chelating agents can be a means of reclaiming lands contaminated by toxic heavy metals. We investigated the ability of a lead- and cadmium-resistant bacterial strain (JB12) and the biodegradable chelator ethylenediamine-N,N'-disuccinic acid (EDDS) to improve absorption of these metals from soil by tall fescue and red clover. Strain JB12 was isolated from contaminated soil samples, analysed for lead and cadmium resistance, and identified as Burkholderia cepacia. Tall fescue and red clover were grown in pots to which we added JB12, (S,S)-EDDS, combined JB12 and EDDS, or water only. Compared with untreated plants, the biomass of plants treated with JB12 was significantly increased. Concentrations of lead and cadmium in JB12-treated plants increased significantly, with few exceptions. Plants treated with EDDS responded variably, but in those treated with combined EDDS and JB12, heavy metal concentrations increased significantly in tall fescue and in the aboveground parts of red clover. We conclude that JB12 is resistant to lead and cadmium. Its application to the soil improved the net uptake of these heavy metals by experimental plants. The potential for viable phytoremediation of lead- and cadmium-polluted soils with tall fescue and red clover combined with JB12 was further enhanced by the addition of EDDS.

Morphological traits and yield of red clover (Trifolium pratense L. genotypes with varying inflorescence length

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Tadeusz Zając

2013-12-01

Full Text Available Two red clover breeding strains with elongated flower heads, developed by one of the authors (H.Góral, were studied for forage and seed yield and compared to the standard cultivar 'Nike'. In addition, six morphological shoot traits were measured and their interrelations were computed. The leaf area index (LAI of successive cuts in two harvest years was determined on the basis of shoot density and leaf area of individual shoots. All three genotypes exhibited a high leaf area on shoots and a very high forage productivity. Among the morphological traits only shoot height could be a good selective criterion because it is easily measured, is significantly associated with shoot weight and shoot leaf area and its variation is low. Both strains, particularly the one with longer inflorescences belong to short-lived red clover forms giving satis factory forage and seed yields in the first harvest year. Depending on the strain the number of seeds per elongated inflorescence in the first harvest year was higher by 92 and 42% compared to that of a standard cultivar.

Radiation induced changes in the cuticular hydrocarbons of the granary weevil and their relationships to desiccation and adult mortality: Annual progress report, February 15, 1986 to February 14, 1987

International Nuclear Information System (INIS)

Sriharan, S.

1987-03-01

The effects of gamma-ray irradiation on granary weevil Sitophilus granarius was studied. Cesium-137 was investigated with regard to its effectiveness in insect disinfestation of grains. The cuticular hydrocarbons of treated and control weevils were analyzed by gas chromatography, mass spectrometry (Gc/Ms). The effects of different dose rates and Relative Humidity (RH) conditions on desiccation were studied by determining body weight and moisture loss. Observations on germination of irradiated wheat seeds were made as complementary to the above studies. The weevils of older age group were more sensitive to gamma radiation. With dose-rate exceeding .15 kGy the mortality is higher during 11 to 15 days after irradiation. While at lower dose-rates 0.01 kGy and 0.05 kGy lower age group insect tend to prolong and survive longer. Analysis of epicuticular hydrocarbons of adult Sitophilus granarius showed that hydrocarbons C 25 to C 33 were present in significant amount. The qualitative and quantitative analysis of irradiated and control weevils suggests that there was little qualitative but considerable quantitative differences between the hydrocarbon fraction (C 25 to C 33 ) in these two groups. 3 refs., 6 figs., 5 tabs

Evaluation of physical structure value in spring-harvested grass/clover silage and hay fed to heifers

DEFF Research Database (Denmark)

Schulze, A.K.S.; Nørgaard, P.; Byskov, M.V.

2015-01-01

The physical structure value of conserved grass/clover forages of spring harvest was evaluated by assessing effects of harvest time, conservation method, iNDF/NDF ratio and NDF intake (NDFI) per kg BW on chewing activity and fecal particle size in dairy heifers. A mixed sward consisting of ryegrass...

Dinitrogen fixation in white clover grown in pure stand and mixture with ryegrass estimated by the immobilized 15N isotope dilution method

DEFF Research Database (Denmark)

Jørgensen, F.V.; Jensen, E.S.; Schjørring, J.K.

1999-01-01

Dinitrogen fixation in white clover (Trifolium repens L.) grown in pure stand and mixture with perennial ryegrass (Lolium perenne L.) was determined in the field using N-15 isotope dilution and harvest of the shoots. The apparent transfer of clover N to perennial ryegrass was simultaneously...... assessed. The soil was labelled either by immobilizing N-15 in organic matter prior to establishment of the sward or by using the conventional labelling procedure in which N-15 fertilizer is added after sward establishment. Immobilization of N-15 in the soil organic matter has not previously been used...

Metabolisable protein supply to lactating dairy cows increased with increasing dry matter concentration in grass-clover silage

DEFF Research Database (Denmark)

Johansen, Marianne; Hellwing, Anne Louise Frydendahl; Lund, Peter

2017-01-01

The aim of this experiment was to study the effect of increased dry matter (DM) concentration in grass-clover silage, obtained by extending the pre-wilting period before ensiling, on the amount of metabolisable protein (MP) supplied to lactating dairy cows. Spring growth and first regrowth of grass...... and faeces, respectively, were collected over 94 h to cover the diurnal variation, pooled, and subsequently analysed. Rumen fluid was collected in same sampling procedure. To estimate the duodenal flow of microbial protein, microbes were isolated from the rumen and analysed for amino acids (AA) and purines...... flow of AA. The higher duodenal flow of AA derived from a lower rumen degradation of feed protein and a tendency towards a higher microbial synthesis in the rumen. Fibre digestibility and CH4 production were not affected by silage DM concentration. In conclusion, MP concentration in grass-clover silage...

Distribution, timing of attack, and oviposition of the banana weevil, Cosmopolites sordidus, on banana crop residues in Uganda

NARCIS (Netherlands)

Masanza, M.; Gold, C.S.; Huis, van A.

2005-01-01

Crop sanitation (removal and chopping of residue corms and pseudostems following plant harvest) has been recommended as a 'best bet' means of reducing banana weevil, Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae), populations. However, it has been unclear when such practices should be

Diversity and numbers of root-nodule bacteria (rhizobia in Polish soils

Directory of Open Access Journals (Sweden)

Stefan Martyniuk

2011-01-01

Full Text Available Using a sand pouch-plant infection method, populations of several species of root-nodule bacteria (rhizobia were enumerated in eighty soils collected throughout Poland. Rhizobium leguminosarum bv. viciae (symbionts of pea, faba bean, vetch and R. leguminosarum bv. trifolii (symbionts of clover were detected in 77 and 76 soils, respectively. Most of these soils contained moderate and high numbers of these species of the rhizobia. Symbionts of beans, R. leguminosarum bv. phaseoli, were assessed in 76 soils; of this number 15 soils had no detectable populations of bean rhizobia and in 40 soils high or moderate numbers of these bacteria were found. Bradyrhizobium sp. (Lupinus, root-nodule bacteria of lupine and serradella, were absent in 19 soils, out of 80 tested, and 34 soils were colonised by high or moderate populations of bradyrhizobia. Sinorhizobium meliloti, rhizobia nodulating alfalfa, were sparse in the examined soils; with 56 soil containing no detectable numbers of S. meliloti and only 6 soils harbouring high or moderate populations of this species. The estimated numbers of the rhizobia in the studied soils were also related to some physical and chemical properties of these soils.

Use of the entomopathogenic nematode Heterorhabditis atacamensis CIA- NE07 in the control of banana weevil Cosmopolites sordidus in vitro

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Marianela Amador

2015-11-01

Full Text Available Among the species of banana borers, black weevil (Cosmopolites sordidus is the most economically important pest in Costa Rica and worldwide. The control of C. sordidus in intensive production systems is mainly based on application of insecticides; therefore the search for biological alternatives, such as the use of entomopathogenic nematodes (EPN, is needed. The susceptibility of Cosmopolites sordidus to Heterorhabditis atacamensis CIANE07 was evaluated. The effect of inoculating H. atacamensis on larvae and adults of C. sordidus, in vitro and in artificially infected corms, was evaluated. Larvae inoculated with EPN had a mortality of 88% on the second day and 100% on the third day; no mortality was observed in adults. The treatments of 100, 500 and 1000 IJ.larvae-1 showed statistically significant differences from the control and theLD50 was 52 IJ.larvae-1. When the larvae were placed within the corms the LD50 increased to 375 IJ.larvae-1. The results indicate that the strain H. atacamensis CIA-NE07 is capable of locating and infecting weevil larvae within the banana corm and reach infection levels over 80%, 10 days after inoculation at doses of 1000 and 2000 IJ.larvae-1. The entomopathogenic nematodes are a viable alternative to be considered in the Integrated Pest Management programs of black weevil, in crops such us banana and plantain.

Effects of entomopathogenic fungus species, and impact of fertilizers, on biological control of pecan weevil (Coleoptera: Curculionidae)

Science.gov (United States)

The pecan weevil, Curculio caryae (Horn), is a key pest of pecan. Prior research indicated potential to use Hypocreales fungi for suppression of C. caryae. In this study, we first compared the efficacy of two fungal spp. Beauveria bassiana (GHA strain) and Metarhizium brunneum (F52) in ability to ...

Assessment of Clover Root Curculio, Sitona puncticollis Stephens (Col.: Curculionidae Injury on Lucerne (Medicago sativa in Pots

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A. Pourhaji

2010-08-01

Full Text Available Alfalfa is one of the most important crops that are infested by Sitona species in Iran. Adults and larvae of Sitona spp. feed on foliage and root of legumes and cause serious damages on them. Collection of adults of this genus during 2003 -2004 years from alfalfa fields of eleven localities in East Azarbaidjan Province, Sitona puncticollis Stephens was found to be the dominant species. To estimate of damage of this species, 100 pots of common alfalfa cultivar (Ghara yonje were sowed and after 2.5 months. Fifty pots were infested with eggs of S. puncticollis and the rests were maintained as control. After two months, length of stem and roots and their dry and fresh weights were measured in 30 infested and 30 uninfested pots. The data of infested and uninfested pots were compared by T- test. Results showed that there were significant differences (P< 0.01 between all measured traits in infested and uninfested pots.

Short-term residual N unaffected by forbs in grass-clover mixtures

DEFF Research Database (Denmark)

Dhamala, Nawa Raj; Rasmussen, Jim; Cong, Wenfeng

2017-01-01

We determined the effect on residual nitrogen (N) of including forbs (chicory, ribwort plantain and caraway) in perennial ryegrass-red clover mixtures. Although soil N inputs during the grassland phase differed markedly between mixtures, in a pot experiment we found no differences...... in the potentially mineralizable N of the soil or in the dry matter production and N content of the spring barley test crop. The fertilizer value of the grassland mixtures corresponded to 10 g N/m2, irrespective of forb inclusion. Thus, the inclusion of nonlegume forbs did not negatively affect short-term residual N...

Pathogenicity evaluation of native isolates of entomopathogenic fungí against andean weevil, Premnotrypes vorax (Hustache

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Giselle Rivera

2001-07-01

Full Text Available The main goal of this study was pathogenicity evaluation of Beauveria bassiana and Metarhizium anisopliae native isolates, obtained from natural habitats and stocked potato, against potato andean weevil, Premnotrypes vorax (Hustache (COLEOPTERA: Curculionidae, and important potato insect pest in Colombia and other Andean countries. Patogenicity was determined by laboratory bioassays, using either reared insects or field captured insects. Insect rearing data are presented. Pathogenicity evaluation was express as mortality against time, estimating LT50 and LT90 for all the fungal isolates, and mortality against spore concentration, estimating CL50 for two selected isolates. In all cases, total mortality percentils were above 45%. Differences between reared and field captured insects were evident. According to obtained data one of the fungal isolates: B. bassiana 9770, obtained from R vorax larva (TL50: 4.7 days - 9.8 days; TL90: 14.1 days - 20.8 days; CL50:7.03 x 104spores/ml appears as a promisory fungal isolate for further studies. Out of this study, differences in the andean weevil, P. vorax, adult mortality, with regard to entomopathogenic fungal isolate and insect origin were manifest.

Nitrate leaching in maize after cultivation of differently managed grass-clover leys on coarse sand in Denmark

DEFF Research Database (Denmark)

Hansen, Elly Møller; Eriksen, Jørgen

2016-01-01

When grass-clover leys have been ploughed nitrate leaching may increase. However, management of leys before or after ploughing may affect the leaching risk. We examined the effect of cultivating a six year ley, which the last two years had been treated differently (grazing only; spring cut follow...

Effect of maturity and conservation of grass/clover on digestibility and rumen pH in heifers

DEFF Research Database (Denmark)

Koch, A.S.; Nørgaard, P.; Weisbjerg, Martin Riis

2013-01-01

The study aimed to evaluate effects of maturity and conservation of primary growth grass/clover on apparent digestibility and rumen pH. Two batches of mixed ryegrass, red and white clover harvested in 2009 on May 9 and 25 were conserved as either silage or hay. The forages early silage (ES) and hay...... (EH), and late silage (LS) and hay (LH) had DM contents of 45, 84, 25 and 83%, and NDF contents of 32, 44, 42 and 50% of DM, respectively. Forages were fed as sole feed to four Jersey heifers of 435±30 kg BW in a 4×4 Latin square experiment. Feeding level was 90% of individual ad libitum intake......, divided in two daily meals at 0800 and 1530 h. Potentially digestible NDF (DNDF) was determined after 288 h in situ. Apparent digestibility of OM and NDF was estimated using Cr3O2 as marker. Rumen fluid pH in the medial and ventral rumen was measured with 1 h intervals from 0730 to 1530 h. Data...

Effects of crop sanitation on banana weevil, Cosmopolites sordidus (Germar) (Coleoptera : Curculionidae), populations and crop damage in Uganda

NARCIS (Netherlands)

Masanza, M.; Gold, C.S.; Huis, van A.; Ragama, P.E.

2006-01-01

Crop sanitation, i.e. destruction of crop residues, has been hypothesized to lower banana weevil damage by removing adult refuges and breeding sites. Although it has been widely recommended to farmers, limited data are available to demonstrate the efficacy of this method. The effects of crop

The Effects of Arbuscular Mycorrhiza Fungi on Dry Matter and Concentrations of Nitrogen, Phosphorus and Potassium in Berseem Clover, by Cadmium stress

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hashem aram

2016-02-01

Zanjan, after the complete analysis of soil and obtaining the chemical and physical properties in the laboratory. 6 kg of soil was weighed for each pot and then the soil was contaminated. Cadmium sulfate was used in this experiment. The mycorrhizal fungi weighed 150 grams and was mixed with the soil. After mixing the soil with mycorrhizal fungi, the soil was put in pots and then it was cultivated with clover. In this study, clover seeds weighed 0/5 grams and were disinfected with 10% hydrogen peroxide solution and were added to each pot. Distilled water was used for irrigation. After the completion of growth of plants (about 70 day, plant aerial parts and roots were harvested and before measuring, they were washed with distilled water and then were dried in the oven for 72 hours. Plant aerial parts were harvested. Data were analyzed by SAS (version 9 and MSTATC (version 2.10 software, and obtained variance analysis tables. Mean comparison of different treatments was conducted by Duncan test. Charts were obtained by excel software. Results and Discussion: The results showed that the effects of arbuscular mycorrhizal fungi were significant on all traits measured (P< 0.01. With increasing cadmium concentration in soil, dry matter of 37% and 39%, nitrogen concentration of 35% and 28%, Potassium 9/27% and 37%, and phosphorus concentration of 37% and 39%, reduced in root and aerial, respectively. Also the results showed that arbuscular mycorrhizal fungi increased dry matter amount by 42% and 26%, nitrogen concentration by 40.3% and 30%, phosphorus concentration by 6% and 15.4%, potassium concentrations by 54% and 91.2% in root and aerial, respectively. Interaction between cadmium levels and mycorrhizal fungi in statistics was significant on dry matter aerial, nitrogen concentration in aerial and root, and potassium concentrations in plant root (P< 0.01. Conclusion: The results showed that mycorrhizal fungi were significant on all traits measured in one percent level. Cadmium

Temporal changes in genetic variation of boll weevil (Coleoptera: Curculionidae) populations, and implications for population assignment in eradication zones

Science.gov (United States)

Genetic differentiation among 10 populations of boll weevil, Anthonomus grandis grandis, sampled in 2009, in Texas and Mexico, was determined using ten microsatellite loci. In addition, temporal changes in genetic composition were examined in the eight populations for which samples were available fr...

Evidence for the presence of a female produced sex pheromone in the banana weevil, Cosmopolites sordidus Germar (Coleoptera: Curculionidae)

Science.gov (United States)

Behavior-modifying chemicals such as pheromones and kairomones have great potential in pest management. Studies reported here investigated chemical cues involved in mating and aggregation behavior of banana weevil, Cosmopolites sordidus, a major insect pest of banana in every country where bananas a...

Bicarbonate as tracer for plant assimilated C and homogeneity of 14C and 15N distribution in ryegrass and white clover tissue by alternative labeling approaches

DEFF Research Database (Denmark)

Rasmussen, Jim; Kusliene, Gedrime; Jacobsen, Ole Stig

2013-01-01

that 15N also had a heterogeneous distribution (up to two orders of magnitude). Conclusion Bicarbonate can efficiently be used to introduce 14C or 13C into plant via the leaf-labeling method. Both 14C and 15N showed heterogeneous distribution in the plant, although the distribution of 15N was more even......Aims: Application of carbon (C) and nitrogen (N) isotopes is an essential tool to study C and N flows in plant-soil-microorganisms systems. When targeting single plants in a community the tracers need to be added via e.g., leaf-labeling or stem-feeding approaches. In this study we: (i) investigated...... if bicarbonate can be used to introduce 14C (or 13C) into white clover and ryegrass, and (ii) compared the patterns of 14C and 15N allocation in white clover and ryegrass to evaluate the homogeneity of tracer distribution after two alternative labeling approaches. Methods Perennial ryegrass and white clover were...

Cotton harvest at 40% versus 75% boll-splitting on yield and economic return under standard and proactive boll weevil (Coleoptera: Curculionidae) spray regimes.

Science.gov (United States)

Showler, A T; Robinson, J R C

2008-10-01

The standard practice of two or three preemptive insecticide applications at the start of pinhead (1-2-mm-diameter) squaring followed by threshold-triggered (when 10% of randomly selected squares have oviposition punctures) insecticide applications for boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), control does not provide reliable protection of cotton, Gossypium hirsutum L., lint production. This study, conducted during 2004 and 2005, showed that three to six fewer spray applications in a "proactive" approach, in which spraying began at the start of large (5.5-8-mm-diameter) square formation and continued at approximately 7-d intervals while large squares were abundant, resulted in fewer infested squares and 1.4- to 1.7-fold more lint than the standard treatment. Fewer sprays and increased yield made proactive spraying significantly more profitable than the standard approach, which resulted in relatively low or negative economic returns. Harvest at 75% boll-split in the proactive spray regime of 2005 resulted in four-fold greater economic return than cotton harvested at 40% boll-split because of improved protection of large squares and the elimination of late-season sprays inherent to standard spray regime despite the cost of an extra irrigation in the 75% boll-split treatments. The earlier, 40% harvest trigger does not avoid high late-season boll weevil pressure, which exerts less impact on bolls, the predominant form of fruiting body at that time, than on squares. Proactive spraying and harvest timing are based on an important relationship between nutrition, boll weevil reproduction, and economic inputs; therefore, the tactic of combining proaction with harvest at 75% boll-split is applicable where boll weevils are problematic regardless of climate or region, or whether an eradication program is ongoing.

Population structure and genetic diversity of the boll weevil, Anthonomus grandis (Coleoptera: Curculionidae), on Gossypium in North America

Science.gov (United States)

While the boll weevil, Anthonomus grandis, has been identified as one of the most devastating pests in U.S. history, its origin and activity in Mexico, both on wild and cultivated cotton hosts (genus Gossypium), is poorly understood. Three forms (geographical or host-associated races) of A. grandis ...

Effect of harvest time of red and white clover silage on chewing activity and particle size distribution in boli, rumen content and faeces in cows.

Science.gov (United States)

Kornfelt, L F; Nørgaard, P; Weisbjerg, M R

2013-06-01

The study examined the effects of harvest time of red and white clover silage on eating and ruminating activity and particle size distribution in feed boli, rumen content and faeces in cows. The clover crops were harvested at two stages of growth and ensiled in bales. Red clover crops had 36% and 45% NDF in dry matter (DM) at early (ER) and late (LR) harvest, respectively, and the white clover crops had 19% and 29% NDF in DM at the early (EW) and late (LW) harvest, respectively. The silages were fed restrictively (80% of ad libitum intake) twice daily to four rumen cannulated non-lactating Jersey cows (588 ± 52 kg) in a 4 × 4 Latin square design. Jaw movements (JM) were recorded for 96 h continuously. Swallowed boli, rumen mat, rumen fluid and faeces samples were collected, washed in nylon bags (0.01 mm pore size) and freeze-dried before dry sieving through 4.750, 2.360, 1.000, 0.500, 0.212 and 0.106 mm into seven fractions. The length (PL) and width (PW) values of rumen and faeces particles within each fraction were measured by use of image analysis. The eating activity (min/kg DM intake; P rumen mat (P rumen fluid (P rumen mat and faeces, but only one peak (mode 1) for PL values. There was no difference in the mean and mode 1 PW and PL value in rumen mat between the four treatments. The mean PL, mode PL, mode 2 PW and mean PW in faeces were highest for LR (P rumen mat and faeces particles are most likely related to the leaves and the stems/petioles. In conclusion, the mean total chewing activity per kg DM was lowest for the white clover silage and increased for both silages due to later harvest time. The mean particle size in boli was smallest for LR, whereas the mean PL and PW in faeces were highest for the LR.

Uptake and Distribution of Added Selenite and Selenate by Barley and Red Clover as Influenced by Sulphur

DEFF Research Database (Denmark)

Nielsen, Gunnar Gissel

1973-01-01

The uptake of added Se from selenite and selenate by barley and red clover was investigated in a pot experiment. Much more of selenate than of selenite was taken up but the Se concentrations in the plants declined more with time when selenate was the source. Increasing sulphate addition to the soil...

Influence of plant and residue age on attraction, acceptance and larval survival of the banana weevil Cosmopolites sordidus (Coleoptera: Curculionidae)

NARCIS (Netherlands)

Masanza, M.; Gold, C.S.; Huis, van A.; Ragama, P.E.

2009-01-01

Laboratory trials were conducted in Uganda at the Kawanda Agricultural Research Institute to determine attraction, eclosion success and larval survivorship of the banana weevil Cosmopolites sordidus (Germar) on crop residues of different ages. In the first experiment, studies focused on different

Predisposition to bark beetle attack by root herbivores and associated pathogens: Roles in forest decline, gap formation, and persistence of endemic bark beetle populations

DEFF Research Database (Denmark)

Aukema, Brian H.; Zhu, Jun; Møller, Jesper

2010-01-01

, however, due to the requirement of long-term monitoring and high degrees of spatial and temporal covariance. We censused more than 2700 trees annually over 7 years, and at the end of 17 years, in a mature red pine plantation. Trees were measured for the presence of bark beetles and wood borers that breed...... within the primary stem, root weevils that breed in root collars, and bark beetles that breed in basal stems. We quantify the sequence of events that drive this decline syndrome, with the primary emergent pattern being an interaction between below- and above-ground herbivores and their fungal symbionts......, and elevated temperature slightly accentuates this effect. New gaps can arise from such trees as they subsequently become epicenters for the full complex of organisms associated with this decline, but this is not common. As Ips populations rise, there is some element of positive feedback...

The life history and immature stages of the weevil Anthonomus monostigma Champion (Coleoptera: Curculiondidae) on Miconia calvescens DC (Melastomataceae)

Science.gov (United States)

Eduardo Chacón-Madrigal; M.Tracy Johnson; Paul. Hanson

2012-01-01

We describe and illustrate the life history and immature stages of Anthonomus monostigma Champion (Curculionidae: Curculioninae: Anthonomini). This weevil is a fruit borer in Miconia calvescens DC (Melastomataceae), a Neotropical tree that is invasive in Pacific islands. The larva has three instars, and development from egg to...

A simple method for preparing artificial larval diet of the West Indian sweetpotato weevil, Euscepes postfasciatus (Fairmaire) (Coleoptera: Curculionidae)

International Nuclear Information System (INIS)

Uesato, T.; Kohama, T.

2008-01-01

The method for preparing ordinary larval artificial diet for Euscepes postfasciatus (old diet) was complicated and time consuming. Some ingredients (casein, saccharose, salt mixture, etc.) of the diet were added to boiled agar solution, others (vitamin mixture, sweetpotato powder, etc.) were added after the solution was cooled to 55degC. To simplify the diet preparation, we combined all ingredients before mixing with water, and then boiled the solution (new diet). There were no significant differences of survival rate (from egg hatching to adult eclosion) and right elytron length between the weevils reared on the old and new diets, but the development period (from egg to adult) of the weevils fed the new diet was significantly (1.3 days) longer than that of those fed the old diet. Preparation time of the new diet was half that of the old diet. These results suggest that simplified diet preparation can be introduced into the mass-rearing of E. postfasciatus

Forage production in mixed grazing systems of elephant grass with arrowleaf clover or forage peanut

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Daiane Cristine Seibt

Full Text Available ABSTRACT Most dairy production systems are pasture-based, usually consisting of sole grass species. This system facilitates pasture management, but results in high production costs, mainly because of nitrogen fertilizers. An alternative to making forage systems more sustainable is to introduce legumes into the pasture. Mixed pastures allow better forage distribution over time and reduce fertilization costs. Thus, the objective of this study was to evaluate, throughout the year, three forage systems (FS: FS1 (control - elephant grass (EG, ryegrass (RG, and spontaneous species (SS; FS2 - EG + RG + SS + arrowleaf clover; and FS3 - EG + RG + SS + forage peanut. Elephant grass was planted in rows spaced 4 m apart. Ryegrass was sown between the EG lines, in the winter. Arrowleaf clover was sown according to the respective treatments and forage peanut was preserved. Evaluation was carried out using Holstein cows. The experiment was arranged in a completely randomized design, with three treatments (FS, and three repetitions (paddocks with repeated measurements (grazing cycles. Forage mass achieved 3.46, 3.80, and 3.91 t ha-1 for the treatments FS1, FS2 and FS3, respectively. The forage systems intercropped with legumes produced the best results.

The Reproductive Morphology and Physiological Age Grading of the Female Salvinia Weevil, Calder and Sands

OpenAIRE

Lee Eisenberg; Seth Johnson; Michael J Grodowitz

2018-01-01

The morphology of the female Cyrtobagous salviniae Calder and Sands reproductive system is similar to other weevil species being meroistic and telotrophic. The reproductive system is composed of 2 ovaries each containing 2 ovarioles where the follicles mature. A physiological age grading system was developed where the continuum of ovarium development was divided into 2 nulliparous and 3 parous classes. This was based on the differentiation of the ovarioles, presence, and appearance of follicu...

Enhancing dissemination of Beauveria bassiana with host plant base incision trapfor the management of the banana weevil Cosmopolites sordidus

NARCIS (Netherlands)

Tinzaara, W.; Emudong, P.; Nankinga, C.; Tushemereirwe, W.; Kagezi, G.H.; Gold, C.S.; Dicke, M.; Huis, van A.; Karamura, E.

2015-01-01

The banana weevil, Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae) is an important pest of highland banana in East and central Africa. It causes yield loss of up to 100% in heavily infested fields. Studies were carried out in Uganda to evaluate the efficacy of the the plant base incision

Transoceanic origin of microendemic and flightless New Caledonian weevils.

Science.gov (United States)

Toussaint, Emmanuel F A; Tänzler, Rene; Balke, Michael; Riedel, Alexander

2017-06-01

The origin of the astonishing New Caledonian biota continues to fuel a heated debate among advocates of a Gondwanan relict scenario and defenders of late oceanic dispersal. Here, we study the origin of New Caledonian Trigonopterus flightless weevils using a multimarker molecular phylogeny. We infer two independent clades of species found in the archipelago. Our dating estimates suggest a Late Miocene origin of both clades long after the re-emergence of New Caledonia about 37 Ma. The estimation of ancestral ranges supports an ancestral origin of the genus in a combined region encompassing Australia and New Guinea with subsequent colonizations of New Caledonia out of New Guinea in the mid-Miocene. The two New Caledonian lineages have had very different evolutionary trajectories. Colonizers belonging to a clade of foliage dwellers greatly diversified, whereas species inhabiting leaf-litter have been less successful.

Reproduction of Meloidogyne incognita on Winter Cover Crops Used in Cotton Production.

Science.gov (United States)

Timper, Patricia; Davis, Richard F; Tillman, P Glynn

2006-03-01

Substantial reproduction of Meloidogyne incognita on winter cover crops may lead to damaging populations in a subsequent cotton (Gossypium hirsutum) crop. The amount of population increase during the winter depends on soil temperature and the host status of the cover crop. Our objectives were to quantify M. incognita race 3 reproduction on rye (Secale cereale) and several leguminous cover crops and to determine if these cover crops increase population densities of M. incognita and subsequent damage to cotton. The cover crops tested were 'Bigbee' berseem clover (Trifolium alexandrinum), 'Paradana' balansa clover (T. balansae), 'AU Sunrise' and 'Dixie' crimson clover (T. incarnatum), 'Cherokee' red clover (T. pratense), common and 'AU Early Cover' hairy vetch (Vicia villosa), 'Cahaba White' vetch (V. sativa), and 'Wrens Abruzzi' rye. In the greenhouse tests, egg production was greatest on berseem clover, Dixie crimson clover, AU Early Cover hairy vetch, and common hairy vetch; intermediate on Balansa clover and AU Sunrise crimson clover; and least on rye, Cahaba White vetch, and Cherokee red clover. In both 2002 and 2003 field tests, enough heat units were accumulated between 1 January and 20 May for the nematode to complete two generations. Both AU Early Cover and common hairy vetch led to greater root galling than fallow in the subsequent cotton crop; they also supported high reproduction of M. incognita in the greenhouse. Rye and Cahaba White vetch did not increase root galling on cotton and were relatively poor hosts for M. incognita. Only those legumes that increased populations of M. incognita reduced cotton yield. In the southern US, M. incognita can complete one to two generations on a susceptible winter cover crop, so cover crops that support high nematode reproduction may lead to damage and yield losses in the following cotton crop. Planting rye or Meloidogyne-resistant legumes as winter cover crops will lower the risk of increased nematode populations

Systemic Insecticides Reduce Feeding, Survival and Fecundity of Adult Black Vine Weevils (Coleoptera: Curculionidae) on a Variety of Ornamental Nursery Crops

Science.gov (United States)

A series of bioassays were conducted to test the systemic activity of clothianidin, chlorantraniliprole, dinotefuran, and thiamethoxam against adult black vine weevils (Otiorhynchus sulcatus F.) on Taxus, Heuchera, Astilbe, Sedum, Euonymus, and Rhododendron grown in containers. The insecticides wer...

A note on the effects of paddock size on the white clover content of swards grazed by sheep

NARCIS (Netherlands)

Wolf, de P.L.; Schulte, R.P.O.; Lantinga, E.A.

2004-01-01

The maintenance of a high white clover content in mixed swards under sheep grazing has been a challenge to date. This paper presents the results of an experiment in which the effect of the length of a grazing period on the botanical composition of a mixed sward was studied. Paddocks ranging in size

Fatty acid composition of ruminal digesta and longissimus muscle from lambs fed silage mixtures including red clover, sainfoin, and timothy.

Science.gov (United States)

Campidonico, L; Toral, P G; Priolo, A; Luciano, G; Valenti, B; Hervás, G; Frutos, P; Copani, G; Ginane, C; Niderkorn, V

2016-04-01

This work investigated the effects of feeding silage mixtures of a plant containing polyphenol oxidase (PPO; red clover [; RC]), a plant containing tannins (sainfoin [; SF]), and a grass species not containing these compounds (timothy [; T]) on ruminal and intramuscular (i.m.) fatty acids of lambs. Forty 4-mo-old castrated male Romane lambs, divided into 5 groups, received 1 of the following silages: 1) T (100%), 2) a binary mixture of timothy and tannin-containing sainfoin ( cv. Perly; 50:50 [T-SF]), 3) a binary mixture of timothy and PPO-containing red clover ( cv. Mervius; 50:50 [T-RC]), 4) a ternary mixture of timothy, sainfoin, and red clover containing both tannins and PPO (50:25:25, respectively [T-SF-RC]), and 5) a binary mixture of tannin-containing sainfoin and PPO-containing red clover (50:50 [SF-RC]). In the rumen digesta, the partial or total replacement of T with forage legumes was associated with greater concentrations of PUFA ( forage legumes in the silage favored the accumulation of 18:3 -3 ( Forage legumes decreased the -11 18:1 to 30% of T in rumen digesta ( Forage legumes decreased the total concentration of branched-chain fatty acids in the rumen digesta (on average, -28%; comparison with T. The dietary treatment tended to affect the proportion of MUFA ( = 0.081) and of PUFA ( = 0.079) in the i.m. fat of the LM, respectively, at the highest and lowest numerical value in the T group. The sum of -3 fatty acids was less in the T and T-SF groups compared with the mixture of legumes without T (SF-RC; comparison with lambs given T-RC, T-SF-RC, and SF-RC. Rumenic acid (-9 -11 CLA) was detected at a greater percentage in the LM from the animals fed the T silage compared with animals fed the T-SF-RC treatment ( = 0.004). Contrarily, -9 -12 -15 18:3 was found at a greater concentration in the muscle from lambs in the SF-RC treatment compared with lambs in the other treatments ( forage for growing lambs in terms of i.m. fatty acid composition.

New uses of clover-grass mixtures in the structure of fodder crops on arable land

Directory of Open Access Journals (Sweden)

Jiří Sláma

2010-01-01

Full Text Available The use of clover-grasses in the structure of fodder crops grown on arable soil, especially those with intergeneric hybrids as the main component part, could avert the negative current trend, i.e. further decreasing the area of perennial fodder plants or fodder crops as a whole on arable soil. They have an irreplaceable role in crop sequences and in preserving the cultural character of the countryside, above all due to the fact that they improve soil fertility and microbial life in the soil and that they have an excellent pre-produce value, and, at the same time, they are applied in various farming systems (both conventional and ecological and in various climatic conditions, and agricultural businesses are well equipped for growing, harvesting and storing them. In the Czech Republic, the area of fodder crops grown on arable soil was decreased from 1,019.9 thousand hectares to mere 396.7 thousand hectares between 1980 and 2009, which is 15.6 % of the total area of arable soil whereas perennial fodder plants only take up 8.5 %. Fodder from clover crops and clover-grass growths on arable soil are one of the main resources of voluminous fodder for dairy cows. Most of this fodder is preserved through a fermentation process (silages, hay storage; a smaller part is fed as fresh fodder, or serves for production of hay. Silages made with perennial fodder plants are the most important source of both proteins and other nutrients for ruminants, especially for high-yielding milch cows. The basis of fodder production systems are the conservative elements of the landscape area (geomorphology in combination with the progressive elements (weather conditions, plants and human labour and relict ones, the representative of which is the soil. The fodder production systems in Europe are divided into five main fodder production zones. From this point of view, the areas where short-term clover-grass mixtures are grown on arable soil could be classed with Zone 4, i

Quantitative historical change in bumblebee (Bombus spp. assemblages of red clover fields.

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Yoko L Dupont

Full Text Available BACKGROUND: Flower visiting insects provide a vitally important pollination service for many crops and wild plants. Recent decline of pollinating insects due to anthropogenic modification of habitats and climate, in particular from 1950's onwards, is a major and widespread concern. However, few studies document the extent of declines in species diversity, and no studies have previously quantified local abundance declines. We here make a quantitative assessment of recent historical changes in bumblebee assemblages by comparing contemporary and historical survey data. METHODOLOGY/PRINCIPAL FINDINGS: We take advantage of detailed, quantitative historical survey data from the 1930's on bumblebee (Bombus spp. abundances and species composition in red clover (Trifolium pratense fields, an important floral resource and an attractant of all bumblebee species. We used the historical survey data as a pre-industrialization baseline, and repeated the same sampling protocol at nearly the same localities at present, hence setting up a historical experiment. We detected historical changes in abundances (bees/m(2 of both workers (the "pollinatory units" and queens (effective population size, in addition to species composition. In particular, long-tongued bumblebee species showed consistent and dramatic declines in species richness and abundances throughout the flowering season of red clover, while short-tongued species were largely unaffected. Of 12 Bombus species observed in the 1930's, five species were not observed at present. The latter were all long-tongued, late-emerging species. CONCLUSIONS/SIGNIFICANCE: Because bumblebees are important pollinators, historical changes in local bumblebee assemblages are expected to severely affect plant reproduction, in particular long-tubed species, which are pollinated by long-tongued bumblebees.

Effect of digestibility of grass-clover silage and concentrate to forage ratio on methane emission from dairy cows

DEFF Research Database (Denmark)

Hellwing, Anne Louise Frydendahl; Weisbjerg, Martin Riis

and D, respectively. TMR forage DM consisted of 2/3 of one of the respective grass-clover silages and 1/3 maize silage, and concentrate (soya meal and wheat) proportion of DM was 20% (low) or 50% (high). Methane emissions from the cows were measured 20-22 hours in one of four chambers working after...

Estimation of the adult male population of sweet potato weevil, Cylas formicarius (Fabricius) at its low-density period on Kikai Island in Japan

International Nuclear Information System (INIS)

Yamaguchi, T.; Hatono, T.; Izumi, S.; Nishihara, S.; Kimura, K.; Torigoe, H.; Tanaka, T.; Miyaji, K.; Hara, Y.; Ueda, A.; Shigei, F.

2008-01-01

The sweet potato weevil, Cylas formicarius (Fabricius) is a major insect pest of the sweet potato, Ipomoea batatas (L.) Lam. throughout the tropical and subtropical regions of the world. We estimated the entire adult male population of C. formicarius at its low-density period on Kikai Island, Kagoshima Pref., Japan. The population of adult males at the high-density period in September was about 5 times larger than that at its low-density period in May, both of which were estimated by Yamamura's method. Using this calculation in combination with an estimate of the maximal population size (4 x 10E6) by Sugimoto et al. in 1994, the total number of male weevils at their low-density period can be assumed to be less than 8 x 10E5

Residues of Malathion and Metabolites in and on the Cotton Leaf vs. Toxicity to the Boll Weevil

Science.gov (United States)

D.A. Wolfenbarger

2002-01-01

Malathion was applied at 12 and 16 oz [A.l.]/a to cotton near Mercedes, TX, in 1995 and sampled on 0, 2, 4 and 6 d posttreatment to determine residues of malathion, malaoxon, and iso-malathion. Residues were then compared to determine toxicity to boll weevil, Anthonomus grandis Boheman. Residues of malathion comprised 99% of the leaf washes and 100% of the leaf...

Effects of Storage and Granary Weevil Infestation on Gel Electrophoresis and Protein Solubility Properties of Hard and Soft Wheat Flours.

Science.gov (United States)

Keskin, Sule; Yalçin, Erkan; Özkaya, Hazim

2018-02-24

The objective of this study was to investigate the effects of storage and granary weevil, Sitophilus granarius (L.; Coleoptera: Curculionidae), infestation on pH, protein solubility (PS) and gel electrophoresis properties of meal and roller-milled flours of hard (Ceyhan-99 cv.) and soft (Eser cv.) wheat cultivars, respectively, after 6 mo of storage. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) technique was applied for studying the electrophoretic properties. Hard and soft wheats were infested with non-sexed S. granarius at a rate of two adults/ kg, and stored for 6 mo at 30 ± 1°C and 70 ± 5% RH. The pest-free wheat samples were used as control. The infested and its control samples were collected monthly, and after cleaning the granary weevils, they were hammer-milled or roller-milled in order to get meal flours and roller-milled flours, respectively. The effect of infestation on the storage proteins was more obvious in meal flours than that of the roller-milled flours. Granary weevil feeding resulted secreting of hydrolyzing enzymes and increased the acidity of flours; subsequently the breaking and releasing of some storage proteins generally caused a decrease in pH and an increase in PS values of the meal flours of wheat cultivars. SDS-PAGE results generally indicated that towards the end of storage, the insect population, that greatly increased, caused minor protein depletions resulting decreasing protein band intensities between 113 and 58 kDa of hard wheat meal flour and 101 and 40 kDa of soft wheat roller-milled flour. Consequently, the potential effect of changes probably occurred in high molecular weight glutenin subunits of both wheat cultivars.

Effect of crop sanitation on banana weevil Cosmopolites sordidus (Germar) (Coleoptera : Curculionidae) populations and crop damage in farmers' fields in Uganda

NARCIS (Netherlands)

Masanza, M.; Gold, C.S.; Huis, van A.; Ragama, P.E.; Okech, S.H.O.

2005-01-01

An on-farm study of the effect of crop sanitation on the banana weevil Cosmopolites sordidus (Germar) populations and corm damage was conducted through farmer participatory trials in Ntungamo district, Uganda. Farmers practiced sanitation levels that were broadly defined as low, moderate and high,

EFFECTS OF WEEVILS (INSECTA: COLEOPTERA: CURCULIONIDAE) CONTROL PRODUCTS, OVER THE GROWTH, DEVELOPMENT, AND PRODUCTION OF PLANTAIN

OpenAIRE

M. Muñoz, Liliana; Cañas, Guillermo L.; Urrea, Aura I.; Guarín, Juan H.

2013-01-01

In a farm in the municipality of Andes (Antioquia, Colombia), parcels were planted with Dominico Hartón plantain associated with Caturra-type coffee, where weevil damage (Insecta: Coleoptera: Curculionidae) occurred in 100% of the plantain plants, corms of approximately 2 kg were planted under the same association system. From the sowing until harvest, six types of products were applied every two months on these plantations: chemical of the region (Clorpirifos and Carboxin + Thiram), Carbofur...

Variation of Body Size in Rice Water Weevil (Coleoptera: Curculionidae) and Its Associations with Population Biology

OpenAIRE

Huang, Yunshan; Ao, Yan; Jiang, Mingxing; Way, Michael O

2018-01-01

Abstract Life history characteristics help us to determine the ability of invasive species to establish and thrive in an exotic environment. However, so far, there have been very few reports concerning geographic variation in the body size of invasive insects and the associations between body size variation and population biology. In this study, we surveyed the geographic variation in body size of an invasive agricultural pest, the rice water weevil Lissorhoptrus oryzophilus Kuschel (Coleopte...

Microbial biomass, microbial diversity, soil carbon storage, and stability after incubation of soil from grass-clover pastures of different age

DEFF Research Database (Denmark)

Müller-Stöver, Dorette Sophie; Hauggaard-Nielsen, Henrik; Eriksen, Jørgen

2012-01-01

A laboratory incubation study with clover grass pasture soils of seven different ages (0, 1, 2, 3, 4, 5, and 16 production years) was carried out to determine initial soil carbon (C) and nitrogen (N) stocks and potentials for greenhouse gas emissions (N2O and CO2). Compared with the soil from...... the recently established pasture, an increase of total soil C and N was observed along with pasture age. Greenhouse gas emissions were low and not significantly different among the soils from younger pastures (0-5 years), but especially N2O emissions increased markedly in the soil from 16-year-old grass......-clover. Low emissions might mainly be due to an early C limitation occurring in the soils from younger pastures, which was also corroborated by decreasing levels of cold water-extractable C and early shifts within the microbial community. However, higher emissions from the old pasture soil were offset by its...

The beneficial effect of dual inoculation of vesicular-arbuscular mycorrhizae + rhizobium on growth of white clover

OpenAIRE

Lin, XG.; Hao, WY.; Wu, TH.

1993-01-01

Investigation on the effect of phosphorus on vesicular-arbuscular mycorrhizal infection, and dual inoculation of vesicular-arbuscular mycorrhizae + rhizobium on growth of white clover under field microplots and pot experiments was conducted on fluvo-aquic soils of semi-arid region in north China. The results showed that 60 kg P205 ha in form of superphosphate was the most favorable phosphorus level for vesicular-arbuscular mycorrhizal infection ; mycorrhizal infection, nodulation, dry weight ...

Uptake and distribution of chlordecone in radish: different contamination routes in edible roots.

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Létondor, Clarisse; Pascal-Lorber, Sophie; Laurent, François

2015-01-01

Chlordecone (CLD) was an organochlorine insecticide mainly used to struggle against banana weevils in the French West Indies. Forbidden since 1993, it has been a long-term contaminant of soils and aquatic environments. Crops growing in contaminated soils lead to human exposure by food consumption. We used radiolabeled [(14)C]-CLD to investigate the contamination ways into radish, a model of edible roots. Radish plants were able to accumulate CLD in both roots (RCF35d 647) and tubers (edible parts, CF35d 6.3). CLD was also translocated to leaves (CF35d 1.7). The contamination of tuber was mainly due to peridermic adsorption or CLD systemic translocation to the pith. TSCF was 3.44×10(-)(3). CLD diffused across periderm to internal tissues. We calculated a mean flux of diffusion J through periderm about 5.71×10(-)(14)gcm(-)(2)s(-)(1). We highlighted different contamination routes of the tuber, (i) adsorption on periderm followed by diffusion of CLD towards underlying tissues, cortex, xylem, and pith (ii) adsorption by roots and translocation by the transpiration stream followed by diffusion from xylem vessels towards inner tissues, pith, and peripheral tissues, cortex and periderm. Concerning chemical risk assessment for other tubers, contamination would depend on various parameters, the thickness of periderm and CLD periderm permeance, the origin of secondary tissues - from cortex and/or pith - , the importance of xylem flow in tuber, and the lipid amount within tuber. Copyright © 2014 Elsevier Ltd. All rights reserved.

Identification of an extensive gene cluster among a family of PPOs in Trifolium pratense L. (red clover using a large insert BAC library

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Thomas Ann

2009-07-01

Full Text Available Abstract Background Polyphenol oxidase (PPO activity in plants is a trait with potential economic, agricultural and environmental impact. In relation to the food industry, PPO-induced browning causes unacceptable discolouration in fruit and vegetables: from an agriculture perspective, PPO can protect plants against pathogens and environmental stress, improve ruminant growth by increasing nitrogen absorption and decreasing nitrogen loss to the environment through the animal's urine. The high PPO legume, red clover, has a significant economic and environmental role in sustaining low-input organic and conventional farms. Molecular markers for a range of important agricultural traits are being developed for red clover and improved knowledge of PPO genes and their structure will facilitate molecular breeding. Results A bacterial artificial chromosome (BAC library comprising 26,016 BAC clones with an average 135 Kb insert size, was constructed from Trifolium pratense L. (red clover, a diploid legume with a haploid genome size of 440–637 Mb. Library coverage of 6–8 genome equivalents ensured good representation of genes: the library was screened for polyphenol oxidase (PPO genes. Two single copy PPO genes, PPO4 and PPO5, were identified to add to a family of three, previously reported, paralogous genes (PPO1–PPO3. Multiple PPO1 copies were identified and characterised revealing a subfamily comprising three variants PPO1/2, PPO1/4 and PPO1/5. Six PPO genes clustered within the genome: four separate BAC clones could be assembled onto a predicted 190–510 Kb single BAC contig. Conclusion A PPO gene family in red clover resides as a cluster of at least 6 genes. Three of these genes have high homology, suggesting a more recent evolutionary event. This PPO cluster covers a longer region of the genome than clusters detected in rice or previously reported in tomato. Full-length coding sequences from PPO4, PPO5, PPO1/5 and PPO1/4 will facilitate

Prediction model for cabbage stem weevil ceutorhynchus pallidactylus Mrsh. occurrence on winther rape based on an artificial neural network

Czech Academy of Sciences Publication Activity Database

Klem, Karel; Spitzer, T.

2017-01-01

Roč. 19, č. 3 (2017), s. 302-308 ISSN 1461-9555 R&D Projects: GA MZe QJ1530373 Institutional support: RVO:67179843 Keywords : Brassica napus L * cabbage stem weevil * Ceutorhynchus pallidactylus * model * neural network * oilseed rape * weather conditions Subject RIV: EG - Zoology OBOR OECD: Environmental sciences (social aspects to be 5.7) Impact factor: 1.726, year: 2016

Responses of the cabbage seedpod weevil, Ceutorhynchus obstrictus (Marsham) (Coleoptera: Curculionidae), to seed treatments of canola (Brassica napus L.) with the neonicotinoid compounds clothianidin and imidacloprid.

Science.gov (United States)

Dosdall, Lloyd M

2009-12-01

The cabbage seedpod weevil, Ceutorhynchus obstrictus (Marsham), is a major pest in the production of canola (Brassica napus L.) in North America and Europe, and effective population control is often essential for economical crop production. In North America, neonicotinoid insecticides have been used for several years in canola as seed treatments for reducing herbivory by flea beetles. The neonicotinoids clothianidin and imidacloprid were investigated to determine their effects on preimaginal development and on emergence of new-generation adults of C. obstrictus in comparison with effects of lindane, a chlorinated hydrocarbon seed treatment. Mean numbers of second- and third-instar larvae were significantly higher in plants seed-treated with lindane than in plants treated with the neonicotinoid compounds, even though weevil oviposition was similar for all treatments. Emergence of new-generation adults was reduced by 52 and 39% for plants seed-treated with clothianidin and imidacloprid, respectively, compared with emergence from plants treated with lindane. Seed treatment with both clothianidin and imidacloprid produced systemic insecticidal effects on larvae of C. obstrictus, with clothianidin slightly more effective than imidacloprid. Use of clothianidin or imidacloprid as seed treatments can comprise an important component in the integrated management of cabbage seedpod weevil in canola. (c) 2009 Society of Chemical Industry.

Amino acid profile of metabolisable protein in lactating dairy cows is affected by dry matter concentration in grass-clover silage

DEFF Research Database (Denmark)

Johansen, Marianne; Lund, Peter; Weisbjerg, Martin Riis

2018-01-01

Our previous study showed that supply of metabolisable protein (MP) to lactating dairy cows increased with increasing dry matter (DM) concentration in grass-clover silage. The aim of this study was to examine how amino acid (AA) profile of MP was affected by silage DM concentration. Eight grass-c...

The clover technique for the treatment of complex tricuspid valve insufficiency: midterm clinical and echocardiographic results in 66 patients.

Science.gov (United States)

Lapenna, Elisabetta; De Bonis, Michele; Verzini, Alessandro; La Canna, Giovanni; Ferrara, David; Calabrese, Maria Chiara; Taramasso, Maurizio; Alfieri, Ottavio

2010-06-01

This study assesses the results of the 'clover technique' (suturing together the middle point of the free edges of the tricuspid leaflets) for the treatment of tricuspid regurgitation (TR) due to severe prolapse or tethering. From 2001, 66 patients with severe TR due to prolapsing or tethered leaflets underwent 'clover repair'. Annuloplasty was associated in 64 patients (97%). The aetiology of TR was degenerative in 52 cases (79%), post-traumatic in eight (12%) and secondary to dilated cardiomyopathy (DCM) in six (9%). The main mechanism of TR was prolapse/flail of one leaflet in 15 patients (23%), of two leaflets in 31 (47%) and of all three leaflets in 14 (21%). The remaining six patients (9%) presented with severe leaflets' tethering. Four deaths (6%) occurred during hospitalisation and one patient died 3.6 years after surgery. Survival was 91 + or - 4.1% at 5 years. Follow-up of the 62 hospital survivors was 100% complete (mean length 3.5 + or - 1.6 years, range 13 months-7.1 years). At the last echocardiogram, no or mild TR was detected in 55 (88.7%) patients, moderate (2+/4+) in six (9.6%) and severe (4+/4+) in one patient (1.6%). Mean tricuspid valve area and gradient were 4.3 + or - 0.6 cm(2) and 2.8 + or -1.4 mmHg. In six patients, stress echocardiography was performed and no signs of tricuspid stenosis were detected. At the multivariable analysis, the degree of TR at hospital discharge was identified as the only predictor of TR > or = 2+ at follow-up. Midterm clinical and echocardiographic results confirm the role of the 'clover technique' in the surgical treatment of TR due to lesions, which are unlikely to be effectively treatable by annuloplasty alone. Copyright 2010 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.

Natural selection drives the fine-scale divergence of a coevolutionary arms race involving a long-mouthed weevil and its obligate host plant

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Toju Hirokazu

2009-01-01

Full Text Available Abstract Background One of the major recent advances in evolutionary biology is the recognition that evolutionary interactions between species are substantially differentiated among geographic populations. To date, several authors have revealed natural selection pressures mediating the geographically-divergent processes of coevolution. How local, then, is the geographic structuring of natural selection in coevolutionary systems? Results I examined the spatial scale of a "geographic selection mosaic," focusing on a system involving a seed-predatory insect, the camellia weevil (Curculio camelliae, and its host plant, the Japanese camellia (Camellia japonica. In this system, female weevils excavate camellia fruits with their extremely-long mouthparts to lay eggs into seeds, while camellia seeds are protected by thick pericarps. Quantitative evaluation of natural selection demonstrated that thicker camellia pericarps are significantly favored in some, but not all, populations within a small island (Yakushima Island, Japan; diameter ca. 30 km. At the extreme, camellia populations separated by only several kilometers were subject to different selection pressures. Interestingly, in a population with the thickest pericarps, camellia individuals with intermediate pericarp thickness had relatively high fitness when the potential costs of producing thick pericarps were considered. Also importantly, some parameters of the weevil - camellia interaction such as the severity of seed infestation showed clines along temperature, suggesting the effects of climate on the fine-scale geographic differentiation of the coevolutionary processes. Conclusion These results show that natural selection can drive the geographic differentiation of interspecific interactions at surprisingly small spatial scales. Future studies should reveal the evolutionary/ecological outcomes of the "fine scale geographic mosaics" in biological communities.

Forage fiber effects on particle size reduction, ruminal stratification, and selective retention in heifers fed highly digestible grass/clover silages.

Science.gov (United States)

Schulze, A K S; Weisbjerg, M R; Storm, A C; Nørgaard, P

2014-06-01

The objective of this study was to investigate the effect of NDF content in highly digestible grass/clover silage on particle size reduction, ruminal stratification, and selective retention in dairy heifers. The reduction in particle size from feed to feces was evaluated and related to feed intake, chewing activity, and apparent digestibility. Four grass/clover harvests (Mixtures of Lolium perenne, Trifolium pratense, and Trifolium repens) were performed from early May to late August at different maturities, at different regrowth stages, and with different clover proportions, resulting in silages with NDF contents of 312, 360, 371, and 446 g/kg DM, respectively, and decreasing NDF digestibility with greater NDF content. Four rumen-fistulated dairy heifers were fed silage at 90% of ad libitum level as the only feed source in a 4 × 4 Latin square design. Silage, ingested feed boluses, medial and ventral ruminal digesta, and feces samples were washed with neutral detergent in nylon bags of 10-μm pore size, freeze dried, and divided into small (1 mm) particles by dry-sieving. Chewing activity, rumen pool size, and apparent digestibility were measured. Intake of NDF increased linearly from 2.3 to 2.8 kg/d with greater NDF content of forages (P = 0.01), but silages were exposed to similar eating time (P = 0.55) and rumination time per kg NDF (P = 0.35). No linear effect of NDF content was found on proportion of LP in ingested feed boluses (P = 0.31), medial rumen digesta (P = 0.95), ventral rumen digesta (P = 0.84), and feces (P = 0.09). Greater proportions of DM (P ruminal digesta compared with ventral rumen, and differences in DM proportion increased with greater NDF content (P = 0.02). Particle size distributions were similar for digesta from the medial and ventral rumen regardless of NDF content of the silages (P > 0.13). The LP proportion was >30% of particles in the ventral and medial rumen, whereas in the feces, the LP proportion was content of the silages

Susceptibility of Anthonomus grandis (cotton boll weevil) and Spodoptera frugiperda (fall armyworm) to a cry1ia-type toxin from a Brazilian Bacillus thuringiensis strain.

Science.gov (United States)

Grossi-de-Sa, Maria Fatima; Quezado de Magalhaes, Mariana; Silva, Marilia Santos; Silva, Shirley Margareth Buffon; Dias, Simoni Campos; Nakasu, Erich Yukio Tempel; Brunetta, Patricia Sanglard Felipe; Oliveira, Gustavo Ramos; Neto, Osmundo Brilhante de Oliveira; Sampaio de Oliveira, Raquel; Soares, Luis Henrique Barros; Ayub, Marco Antonio Zachia; Siqueira, Herbert Alvaro Abreu; Figueira, Edson L Z

2007-09-30

Different isolates of the soil bacterium Bacillus thuringiensis produce multiple crystal (Cry) proteins toxic to a variety of insects, nematodes and protozoans. These insecticidal Cry toxins are known to be active against specific insect orders, being harmless to mammals, birds, amphibians, and reptiles. Due to these characteristics, genes encoding several Cry toxins have been engineered in order to be expressed by a variety of crop plants to control insectpests. The cotton boll weevil, Anthonomus grandis, and the fall armyworm, Spodoptera frugiperda, are the major economically devastating pests of cotton crop in Brazil, causing severe losses, mainly due to their endophytic habit, which results in damages to the cotton boll and floral bud structures. A cry1Ia-type gene, designated cry1Ia12, was isolated and cloned from the Bt S811 strain. Nucleotide sequencing of the cry1Ia12 gene revealed an open reading frame of 2160 bp, encoding a protein of 719 amino acid residues in length, with a predicted molecular mass of 81 kDa. The amino acid sequence of Cry1Ia12 is 99% identical to the known Cry1Ia proteins and differs from them only in one or two amino acid residues positioned along the three domains involved in the insecticidal activity of the toxin. The recombinant Cry1Ia12 protein, corresponding to the cry1Ia12 gene expressed in Escherichia coli cells, showed moderate toxicity towards first instar larvae of both cotton boll weevil and fall armyworm. The highest concentration of the recombinant Cry1Ia12 tested to achieve the maximum toxicities against cotton boll weevil larvae and fall armyworm larvae were 230 microg/mL and 5 microg/mL, respectively. The herein demonstrated insecticidal activity of the recombinant Cry1Ia12 toxin against cotton boll weevil and fall armyworm larvae opens promising perspectives for the genetic engineering of cotton crop resistant to both these devastating pests in Brazil.

Report on the intercomparison run IAEA-156 radionuclides in clover

International Nuclear Information System (INIS)

Strachnov, V.; Valkovic, V.; Dekner, R.

1991-01-01

This report contains the results of the intercomparison IAEA-156 on the determination of radionuclides in clover. Initially participants were requested to determine the levels of 134 Cs, 137 Cs, 40 K, 90 Sr and invited to provide data for other radionuclides. The participants included 46 laboratories located in 25 countries, and statistical evaluation of their data yield recommended values for these four radionuclides. Additional radionuclides reported were 210 Pb, 239 Pu and 125 Sb; however, insufficient data exists to statistically determine recommended values for these radionuclides. The following are the recommended values, with confidence intervals, for the most frequently measured radionuclides (reference date: 1 August 1986): 134 Cs 132.1 Bq/kg (126.4-137.7); 137 Cs 264 Bq/kg (254-274); 40 K 657 Bq/kg (637-676); 90 Sr 14.8 Bq/kg (13.4-16.3). Figs and tabs

Breeding biologies, pollinators and seed beetles of two prairie-clovers, Dalea ornata and D. searlsiae (Fabaceae: Amorpheae), from the Intermountain West USA

Science.gov (United States)

Two prairie-clovers, Dalea ornata and D. searlsiae, are perennial forbs that flower during early summer throughout the Colombia Plateau and Great Basin of the western USA, respectively. Their seed is desirable for use in rangeland restoration. We experimentally characterized the breeding biologies ...

Selection of Beauveria bassiana sensu lato and Metarhizium anisopliae sensu lato isolates as microbial control agents against the boll weevil (Anthonomus grandis) in Argentina.

Science.gov (United States)

Nussenbaum, A L; Lecuona, R E

2012-05-01

The boll weevil (Anthonomus grandis) is the main pest of cotton in the Americas. The aim of this work was to evaluate isolates of the entomopathogenic fungi Beauveria bassiana sensu lato and Metarhizium anisopliae sensu lato virulent against A. grandis. Screening was performed to evaluate the pathogenicity of 28 isolates of M. anisopliae s.l. and 66 isolates of B. bassiana s.l. against boll weevil adults. To select the isolates, LC(50) values of the most virulent isolates were calculated, and compatibility between the fungi and insecticides was studied. In addition, the effects of these isolates on the feeding behavior of the adults were evaluated. Isolates Ma 50 and Ma 20 were the most virulent against A. grandis and their LC(50) values were 1.13×10(7) and 1.20×10(7) conidia/ml, respectively. In addition, these isolates were compatible with pyrethroid insecticides, but none with endosulfan. On the other hand, infected females reduced the damage caused by feeding on the cotton squares and their weight gain. This shows that entomopathogenic fungi cause mortality in the insects, but also these fungi could influence the feeding behavior of the females. In summary, these results indicate the possibility of the use of M. anisopliae s.l. as a microbiological control agent against boll weevils. Also, this species could be included in an Integrated Pest Management program. Copyright © 2012 Elsevier Inc. All rights reserved.

Utilization of kura clover-reed canarygrass silage versus alfalfa silage by lactating dairy cows.

Science.gov (United States)

Kammes, K L; Heemink, G B H; Albrecht, K A; Combs, D K

2008-08-01

The mixture of kura clover (Trifolium ambiguum M. Bieb.) and reed canarygrass (Phalaris arundinacea L.) has proven to be extremely persistent in the northern United States, but information about dairy cow performance on this mixture is lacking. Twenty lactating Holstein cows were used in a crossover design to compare dry matter (DM) intake and milk production from diets containing kura clover-reed canarygrass silage (KRS) or alfalfa (Medicago sativa L.) silage (AS). Forages were cut, wilted, ensiled in horizontal plastic bags, and allowed to ferment for at least 50 d before beginning the feeding experiment. The KRS was approximately 40% kura clover and 60% reed canarygrass. Treatments were total mixed rations formulated with either 57% of total DM from 1) AS or 2) KRS. Experimental periods were 28 d, with the first 14 d for diet adaptation and the last 14 d for measurement of intake and milk production. The neutral detergent fiber (NDF) concentrations of AS and KRS were 37.3 and 47.3%, respectively. The fermentation analyses indicated that both silages underwent a restricted fermentation, producing primarily lactic acid and some acetic acid. Dry matter intake (24.2 vs. 22.8 kg) and 4% fat-corrected milk (32.8 vs. 30.9 kg) were significantly higher for cows fed AS than for cows fed KRS. Cows consumed less NDF (6.7 vs. 8.0 kg) and less digestible NDF (3.0 vs. 4.4 kg) when fed AS diets compared with KRS diets, but the pool of ruminally undegraded NDF was similar (3.7 kg) between diets. Cows produced 1.5 kg of milk/kg of DM consumed regardless of the diet, indicating that digestible NDF of KRS was utilized with similar efficiency as the cell wall constituents of AS, but the intake of cows fed KRS may have been limited by rumen fill. Milk fat concentration tended to be higher for cows fed AS, but the milk true protein concentration and yields of fat and protein did not differ by treatment. Milk urea nitrogen content was higher when cows consumed AS (16.4 mg/ d

Climate Clever Clovers: New Paradigm to Reduce the Environmental Footprint of Ruminants by Breeding Low Methanogenic Forages Utilizing Haplotype Variation

Directory of Open Access Journals (Sweden)

Parwinder Kaur

2017-09-01

Full Text Available Mitigating methane production by ruminants is a significant challenge to global livestock production. This research offers a new paradigm to reduce methane emissions from ruminants by breeding climate-clever clovers. We demonstrate wide genetic diversity for the trait methanogenic potential in Australia’s key pasture legume, subterranean clover (Trifolium subterraneum L.. In a bi-parental population the broadsense heritability in methanogenic potential was moderate (H2 = 0.4 and allelic variation in a region of Chr 8 accounted for 7.8% of phenotypic variation. In a genome-wide association study we identified four loci controlling methanogenic potential assessed by an in vitro fermentation system. Significantly, the discovery of a single nucleotide polymorphism (SNP on Chr 5 in a defined haplotype block with an upstream putative candidate gene from a plant peroxidase-like superfamily (TSub_g18548 and a downstream lectin receptor protein kinase (TSub_g18549 provides valuable candidates for an assay for this complex trait. In this way haplotype variation can be tracked to breed pastures with reduced methanogenic potential. Of the quantitative trait loci candidates, the DNA-damage-repair/toleration DRT100-like protein (TSub_g26967, linked to avoid the severity of DNA damage induced by secondary metabolites, is considered central to enteric methane production, as are disease resistance (TSub_g26971, TSub_g26972, and TSub_g18549 and ribonuclease proteins (TSub_g26974, TSub_g26975. These proteins are good pointers to elucidate the genetic basis of in vitro microbial fermentability and enteric methanogenic potential in subterranean clover. The genes identified allow the design of a suite of markers for marker-assisted selection to reduce rumen methane emission in selected pasture legumes. We demonstrate the feasibility of a plant breeding approach without compromising animal productivity to mitigate enteric methane emissions, which is one of the most

Silencing the Odorant Binding Protein RferOBP1768 Reduces the Strong Preference of Palm Weevil for the Major Aggregation Pheromone Compound Ferrugineol

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Binu Antony

2018-03-01

Full Text Available In insects, perception of the environment—food, mates, and prey—is mainly guided by chemical signals. The dynamic process of signal perception involves transport to odorant receptors (ORs by soluble secretory proteins, odorant binding proteins (OBPs, which form the first stage in the process of olfactory recognition and are analogous to lipocalin family proteins in vertebrates. Although OBPs involved in the transport of pheromones to ORs have been functionally identified in insects, there is to date no report for Coleoptera. Furthermore, there is a lack of information on olfactory perception and the molecular mechanism by which OBPs participate in the transport of aggregation pheromones. We focus on the red palm weevil (RPW Rhynchophorus ferrugineus, the most devastating quarantine pest of palm trees worldwide. In this work, we constructed libraries of all OBPs and selected antenna-specific and highly expressed OBPs for silencing through RNA interference. Aggregation pheromone compounds, 4-methyl-5-nonanol (ferrugineol and 4-methyl-5-nonanone (ferruginone, and a kairomone, ethyl acetate, were then sequentially presented to individual RPWs. The results showed that antenna-specific RferOBP1768 aids in the capture and transport of ferrugineol to ORs. Silencing of RferOBP1768, which is responsible for pheromone binding, significantly disrupted pheromone communication. Study of odorant perception in palm weevil is important because the availability of literature regarding the nature and role of olfactory signaling in this insect may reveal likely candidates representative of animal olfaction and, more generally, of molecular recognition. Knowledge of OBPs recognizing the specific pheromone ferrugineol will allow for designing biosensors for the detection of this key compound in weevil monitoring in date palm fields.

Preliminary field studies on the control of the red palm weevil, Rhynchophorus ferrugineus Oliv., using radiosterilized males

International Nuclear Information System (INIS)

Rahalkar, G.W.; Harwalkar, M.R.; Rananavare, H.D.

1977-01-01

Feasibility of using sterile male release method for the control of red palm weevil, Rhynchophorus ferrungineus Oliv., a serious pest of coconut and other cultivated palms in India was investigated. A total of over 5000 radiosterilized males were released in an 800 acre coconut plantation near Kayangulam in Kerala. Data on the fertility pattern of native females is presented and the factors affecting the efficacy of sterile male release for control of this insect are discussed. (author)

Fate of 15N and 14C from labelled plant material

DEFF Research Database (Denmark)

Rasmussen, Jim; Gjettermann, Birgitte; Eriksen, Jørgen

2008-01-01

strength of labelled plant residues in dissolved inorganic N (DIN) and dissolved organic N (DON) in pore water from the plough layer, and (ii) the plant uptake of organically bound N. Litterbags containing 14C- and 15N-labelled ryegrass or clover roots or leaves were inserted into the sward of a ryegrass......–clover mixture in early spring. The fate of the released 14C and 15N was monitored in harvested biomass, roots, soil, and pore water percolating from the plough layer. No evidence of plant uptake of dual-labelled organic compounds from the dual-labelled residues could be observed. N in pore water from the plough...

Effect of toasting field beans and of grass-clover

DEFF Research Database (Denmark)

Mogensen, Lisbeth; Vestergaard, Jannie Steensig; Fretté, Xavier

2010-01-01

The effect of toasting field beans and of grass-clover: maize silage ratio on milk production, milk composition and the sensory quality of the milk was investigated in a 2   2 factorial experiment. Toasting of field beans resulted in lower milk contents of both fat (44.2 versus 46.1 g/kg, P = 0.......02) and protein (33.5 versus 34.2 g/kg, P = 0.008), whereas milk production, urea and somatic cell contents were unaffected compared with the untreated field beans. Increasing the proportion of maize silage (from 9 to 21% of DM) in the ration decreased the content of urea in milk (P = 0.002), whereas milk......-β-carotene (P = 0.04) and β-carotene (P = 0.05). Toasting of field beans compared with untreated field beans did not affect the milk content of carotenoids and had only small effects on fatty acid composition. Regarding the sensory quality, the four treatments resulted in milk being characterized...

Effects of forest management on running buffalo clover (Trifolium stoloniferum Muhl. Ex A. Eaton) distribution and abundance in the Fernow Experimental Forest

Science.gov (United States)

J.Q. Burkhart; J.R. Rentch; T.M. Schuler

2013-01-01

Identifying habitat preferences of species of concern is fundamental to the practice of conservation, but disturbances and other environmental processes can substantially affect suitability. Trifolium stoloniferum, or running buffalo clover, is a federally endangered plant species that occurs on the Fernow Experimental Forest in West Virginia....

Annual maize and perennial grass-clover strip cropping for increased resource use efficiency and productivity using organic farming practice as a model

DEFF Research Database (Denmark)

Hauggaard-Nielsen, Henrik; Johansen, Anders; Carter, Mette Sustmann

2013-01-01

A cropping system was designed to fulfill the increasing demand for biomass for food and energy without decreasing long term soil fertility. A field experiment was carried out including alternating strips of annual maize (Zea mays L.) and perennial ryegrass (Lolium perenne L.) – clover (Trifolium...

Measured and simulated performance of Compton-suppressed TIGRESS HPGe clover detectors

Science.gov (United States)

Schumaker, M. A.; Hackman, G.; Pearson, C. J.; Svensson, C. E.; Andreoiu, C.; Andreyev, A.; Austin, R. A. E.; Ball, G. C.; Bandyopadhyay, D.; Boston, A. J.; Chakrawarthy, R. S.; Churchman, R.; Drake, T. E.; Finlay, P.; Garrett, P. E.; Grinyer, G. F.; Hyland, B.; Jones, B.; Maharaj, R.; Morton, A. C.; Phillips, A. A.; Sarazin, F.; Scraggs, H. C.; Smith, M. B.; Valiente-Dobón, J. J.; Waddington, J. C.; Watters, L. M.

2007-01-01

Tests of the performance of a 32-fold segmented HPGe clover detector coupled to a 20-fold segmented Compton-suppression shield, which form a prototype element of the TRIUMF-ISAC Gamma-Ray Escape-Suppressed Spectrometer (TIGRESS), have been made. Peak-to-total ratios and relative efficiencies have been measured for a variety of γ-ray energies. These measurements were used to validate a GEANT4 simulation of the TIGRESS detectors, which was then used to create a simulation of the full 12-detector array. Predictions of the expected performance of TIGRESS are presented. These predictions indicate that TIGRESS will be capable, for single 1 MeV γ rays, of absolute detection efficiencies of 17% and 9.4%, and peak-to-total ratios of 54% and 61% for the "high-efficiency" and "optimized peak-to-total" configurations of the array, respectively.

Distribution of radionuclides in leaf-stem biomass of lupine and clover under production of protein concentrates

International Nuclear Information System (INIS)

Novikov, Yu.F.; Lobach, G.A.; Buzenko, T.A.; Zaretskaya, T.P.

1993-01-01

The basic regularities of radionuclide distribution between the obtained products have been studied using the fractionation of lupine and clover phytomass as an example. The content of radionuclides in protein concentrates has been shown to be strongly related to the crop species. A scheme and a regime of the fractionation of leaf-stem lupine biomass contaminated with cesium radioisotopes and strontium-90 which ensured the minimizing of their residual content in protein-vitaminic and protein concentrates have been selected with due accout of experimental data

[Radiation induced changes in the cuticular hydrocarbons of the granary weevil and their relationship to dessication and adult mortality]. Half-yearly report, February 15-August 14, 1986

International Nuclear Information System (INIS)

1986-01-01

Granary weevil (Sitophilus granarius) were irradiated with cesium-137 derived gamma radiation at various age groups. Hydrocarbon analysis of epicuticles were studied chromatographically and by mass spectroscopy. 3 figs., 4 tabs. (DT)

Effect of Irrigation on Within-Grove Distribution of Red Palm Weevil Rhynchophorous ferrugineus

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Y. Aldryhim

2003-01-01

Full Text Available The red palm weevil (RPW Rhynchophorous ferrugineus (Oliv. is the most important pest attacking date palm trees. The objective of this study was to determine the effect of drip and flood irrigation on the within-grove distribution of RPW. The current study was started with the first appearance of the infestation to almost disappearance of the infestation. Results showed that more infested trees were detected in plots with flood irrigation. The number of infested trees in these plots represented 89% of the total infested trees. This study suggested that irrigation management and soil moisture are key factors in the dispersion of the RPW infestation and could be used as one of the integrated pest management tools.

Egg distribution and sampling of Diaprepes abbreviatus (Coleoptera: Curculionidae) on silver buttonwood

International Nuclear Information System (INIS)

Pena, J.E.; Mannion, C.; Amalin, D.; Hunsberger, A.

2007-01-01

Taylor's power law and Iwao's patchiness regression were used to analyze spatial distribution of eggs of the Diaprepes root weevil, Diaprepes abbreviatus (L.), on silver buttonwood trees, Conocarpus erectus, during 1997 and 1998. Taylor's power law and Iwao's patchiness regression provided similar descriptions of variance-mean relationship for egg distribution within trees. Sample size requirements were determined. Information presented in this paper should help to improve accuracy and efficiency in sampling of the weevil eggs in the future. (author) [es

Nucleases as a barrier to gene silencing in the cotton boll weevil, Anthonomus grandis.

Science.gov (United States)

Almeida Garcia, Rayssa; Lima Pepino Macedo, Leonardo; Cabral do Nascimento, Danila; Gillet, François-Xavier; Moreira-Pinto, Clidia Eduarda; Faheem, Muhammad; Moreschi Basso, Angelina Maria; Mattar Silva, Maria Cristina; Grossi-de-Sa, Maria Fatima

2017-01-01

RNA interference (RNAi) approaches have been applied as a biotechnological tool for controlling plant insect pests via selective gene down regulation. However, the inefficiency of RNAi mechanism in insects is associated with several barriers, including dsRNA delivery and uptake by the cell, dsRNA interaction with the cellular membrane receptor and dsRNA exposure to insect gut nucleases during feeding. The cotton boll weevil (Anthonomus grandis) is a coleopteran in which RNAi-mediated gene silencing does not function efficiently through dsRNA feeding, and the factors involved in the mechanism remain unknown. Herein, we identified three nucleases in the cotton boll weevil transcriptome denoted AgraNuc1, AgraNuc2, and AgraNuc3, and the influences of these nucleases on the gene silencing of A. grandis chitin synthase II (AgraChSII) were evaluated through oral dsRNA feeding trials. A phylogenetic analysis showed that all three nucleases share high similarity with the DNA/RNA non-specific endonuclease family of other insects. These nucleases were found to be mainly expressed in the posterior midgut region of the insect. Two days after nuclease RNAi-mediated gene silencing, dsRNA degradation by the gut juice was substantially reduced. Notably, after nucleases gene silencing, the orally delivered dsRNA against the AgraChSII gene resulted in improved gene silencing efficiency when compared to the control (non-silenced nucleases). The data presented here demonstrates that A. grandis midgut nucleases are effectively one of the main barriers to dsRNA delivery and emphasize the need to develop novel RNAi delivery strategies focusing on protecting the dsRNA from gut nucleases and enhancing its oral delivery and uptake to crop insect pests.

The Growth Rate and Efficiency of Rumen Microbial Protein Digestion of Red Clover Silage (Trifolium pratense cv. Sabatron)

International Nuclear Information System (INIS)

Asih Kurniawati

2004-01-01

(Trifolium pratense cv. Sabatron). Red clover silage supplemented with different level of carbohydrates has been examined using the in-vitro gas production technique. Cumulative gas production, hydro.gen sulfite production, and ammonia was followed and used as indicators of microbial growth rate and extent of protein degradation. Microbial nitrogen production, VFA, and efficiency microbial production was used as indicator of nitrogen use efficiency. 15 N was used as a microbial marker to estimate the amount of nitrogen incorporation into microbial protein. Supplementation of Red clover with increasing 5 levels; 0 g; 0.625 g; 0.15 g; 0.225 g and 0.3 g of maize starch led to graded increase in microbial growth and protein degradation. This was reflected in the increasing gas production and the accumulation of hydrogen sulfite. Diurnal change in ammonia production reflected the microbial utilization of ammonia for protein synthesis. Protein microbe (P<0.001) as VFA (P<0.001) increased due to carbohydrate addition as well as utilization of nitrogen (P<0.001). There was also the efficiency of nitrogen utilization which increased significantly. This result suggested that energy supply can increased efficiency of nitrogen use in the rumen and may reduce nitrogen losses into the environment. (author)

Spatial and temporal distribution of cotton squares and small cotton bolls fallen on ground after damage by boll weevil and the efficiency of the equipment used to collect them

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Carlos Alberto Domingues da Silva

Full Text Available ABSTRACT: In this study, we determined the spatial and temporal distribution of fallen cotton squares and small cotton bolls fallen damaged by boll weevil and the efficiency and time interval of the equipment used to collect cotton samples. Spatial and temporal distribution of cotton squares and small cotton bolls fallen on the soil damaged by boll weevil among cotton rows was determined in an experimental design of randomized blocks in a factorial arrangement of 4x3, represented by soil surface tracks located at 1-11cm, 12-22cm, 23-33cm, and 34-44cm away from the planting row of cotton plants 70, 85, and 100 days of age. Efficiency and collection time interval of the cotton samples fallen on the soil infested by boll weevil by plastic rakes that were straight or fan-shaped, big broom, collector instrument model CNPA and aspirator of leaves ‘Trapp’ were determined in randomized block design with five treatments, 10 repetitions for each. Results demonstrated that the collection of cotton samples must be performed with greater attention to soil strips located below the cotton top projection and aspirator ‘Trapp’ of leaves was more appropriate for the operation as it used less time of collection with similar efficiency to other available equipment.

Forage mass and the nutritive value of pastures mixed with forage peanut and red clover

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Ricardo Lima de Azevedo Junior

2012-04-01

Full Text Available The objective of this research was to estimate three pasture-based systems mixed with elephantgrass + spontaneous growth species, annual ryegrass, for pasture-based system 1; elephantgrass + spontaneous growth species + forage peanut, for pasture-based system 2; and elephantgrass + spontaneous growth species + annual ryegrass + red clover, for pasture-based system 3. Elephantgrass was planted in rows 4 m apart from each other. During the cool-season, annual ryegrass was sown in the alleys between the rows of elephantgrass; forage peanut and red clover were sown in the alleys between the elephantgrass according to the respective treatment. The experimental design was totally randomized in the three treatments (pasture-based systems, two replicates (paddocks in completely split-plot time (grazing cycles. Holstein cows receiving 5.5 kg-daily complementary concentrate feed were used in the evaluation. Pre-grazing forage mass, botanical composition and stocking rate were evaluated. Samples of simulated grazing were collected to analyze organic matter (OM, neutral detergent fiber (NDF, crude protein (CP and organic matter in situ digestibility (OMISD. Nine grazing cycles were performed during the experimental period (341 days. The average dry matter values for pre-grazing and stocking rate were 3.34; 3.46; 3.79 t/ha, and 3.28; 3.34; 3.60 AU/ha for each respective pasture-based system. Similar results were observed between the pasture-based systems for OM, NDF, CP and OMISD. Considering forage mass, stocking rate and nutritive value, the pasture-based system intercropped with forage legumes presented better performance.

Characterisation of a Compton suppressed Clover detector for high energy gamma rays (=<11MeV)

International Nuclear Information System (INIS)

Saha Sarkar, M.; Kshetri, Ritesh; Raut, Rajarshi; Mukherjee, A.; Sinha, Mandira; Ray, Maitreyi; Goswami, A.; Roy, Subinit; Basu, P.; Majumder, H.; Bhattacharya, S.; Dasmahapatra, B.

2006-01-01

Gamma ray spectra of two (p,γ) resonances have been utilised for the characterisation of the Clover detector at energies beyond 5MeV. Apart from the efficiency and the resolution of the detector, the shapes of the full energy peaks as well as the nature of the escape peaks which are also very crucial at higher energies have been analysed with special attention. Proper gain matching in software have checked deterioration in the energy resolution and distortion in the peak shape due to addback. The addback factors show sharp increasing trend even at energies around 11MeV

Characterisation of a Compton suppressed Clover detector for high energy gamma rays (=<11MeV)

Energy Technology Data Exchange (ETDEWEB)

Saha Sarkar, M. [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India)]. E-mail: maitrayee.sahasarkar@saha.ac.in; Kshetri, Ritesh [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India); Raut, Rajarshi [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India); Mukherjee, A. [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India); Sinha, Mandira [Gurudas College, Narkeldanga, Kolkata-700054 (India); Ray, Maitreyi [Behala College, Parnashree, Kolkata-700060 (India); Goswami, A. [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India); Roy, Subinit [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India); Basu, P. [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India); Majumder, H. [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India); Bhattacharya, S. [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India); Dasmahapatra, B. [Saha Institute of Nuclear Physics, 1/AF Bidhan Nagar, Kolkata-700064 (India)

2006-01-01

Gamma ray spectra of two (p,{gamma}) resonances have been utilised for the characterisation of the Clover detector at energies beyond 5MeV. Apart from the efficiency and the resolution of the detector, the shapes of the full energy peaks as well as the nature of the escape peaks which are also very crucial at higher energies have been analysed with special attention. Proper gain matching in software have checked deterioration in the energy resolution and distortion in the peak shape due to addback. The addback factors show sharp increasing trend even at energies around 11MeV.

Different bioassays for investigating orientation responses of the banana weevil, Cosmopolites sordidus, show additive effects of host plant volatiles and a synthetic male-produced aggregation pheromone

NARCIS (Netherlands)

Tinzaara, W.; Dicke, M.; Huis, van A.; Loon, van J.A.; Gold, C.S.

2003-01-01

Three different bioassay methods to investigate the orientation behaviour of the banana weevil, Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae), to host plant volatiles and a synthetic pheromone (cosmolure+) were compared. A locomotion compensator was used to separately record walking

Biochanin A (an isoflavone produced by red clover) promotes weight gain of steers grazed in mixed grass pastures and fed dried-distillers grains

Science.gov (United States)

Biochanin A (BCA) is an isoflavone produced by red clover (Trifloium pratense L.) that can inhibit hyper-ammonia producing bacteria (HAB) to reduce deamination in the rumen and increase the feed amino acids available for gastric digestion. An in vitro experiment was conducted to evaluate the effect...

Screenhouse and field persistence of nonpathogenic endophytic Fusarium oxysporum in Musa tissue culture plants.

Science.gov (United States)

Paparu, Pamela; Dubois, Thomas; Gold, Clifford S; Niere, Björn; Adipala, Ekwamu; Coyne, Daniel

2008-04-01

Two major biotic constraints to highland cooking banana (Musa spp., genome group AAA-EA) production in Uganda are the banana weevil Cosmopolites sordidus and the burrowing nematode Radopholus similis. Endophytic Fusarium oxysporum strains inoculated into tissue culture banana plantlets have shown control of the banana weevil and the nematode. We conducted screenhouse and field experiments to investigate persistence in the roots and rhizome of two endophytic Fusarium oxysporum strains, V2w2 and III4w1, inoculated into tissue-culture banana plantlets of highland cooking banana cultivars Kibuzi and Nabusa. Re-isolation of F. oxysporum showed that endophyte colonization decreased faster from the rhizomes than from the roots of inoculated plants, both in the screenhouse and in the field. Whereas rhizome colonization by F. oxysporum decreased in the screenhouse (4-16 weeks after inoculation), root colonization did not. However, in the field (17-33 weeks after inoculation), a decrease was observed in both rhizome and root colonization. The results show a better persistence in the roots than rhizomes of endophytic F. oxysporum strains V2w2 and III4w1.

The effects of PPO activity on the proteome of ingested red clover and implications for improving the nutrition of grazing cattle.

Science.gov (United States)

Hart, E H; Onime, L A; Davies, T E; Morphew, R M; Kingston-Smith, A H

2016-06-01

Increasing the rumen-stable protein content of feed would lead to improved nitrogen utilisation in cattle, and less nitrogenous waste. Red clover (Trifolium pratense L.) is a high protein ruminant feed containing high polyphenol oxidase (PPO) activity. PPO mediated protein-quinone binding has been linked to protecting plant proteins from proteolysis. To explore the mechanism underlying the effect of PPO on protein protection in fresh forage feeds, proteomic components of feed down-boli produced from wild-type red clover and a low PPO mutant, at point of ingestion and after 4h in vitro incubation with rumen inoculum were analysed. Significant differences in proteomic profiles between wild-type and mutant red clover were determined after 4h incubation, with over 50% less spots in mutant than wild-type proteomes, indicating decreased proteolysis in the latter. Protein identifications revealed preferentially retained proteins localised within the chloroplast, suggesting that PPO mediated protection in the wild-type operates due to the proximity of target proteins to the enzyme and substrates, either diffusing into this compartment from the vacuole or are present in the chloroplast. This increased understanding of protein targets of PPO indicates that wider exploitation of the trait could contribute to increased protein use efficiency in grazing cattle. One of the main challenges for sustainable livestock farming is improving capture of dietary nitrogen by ruminants. Typically up to 70% of ingested protein-N is excreted representing a loss of productivity potential and a serious environmental problem in terms of nitrogenous pollution of lands and water. Identification of key characteristics of rumen-protected protein will deliver target traits for selection in forage breeding programmes. The chloroplastic enzyme PPO catalyzes the oxidation of phenols to quinones, which react with protein. Little is currently known about the intracellular protein targets of the products

Components and Insecticidal Activity against the Maize Weevils of Zanthoxylum schinifolium Fruits and Leaves

Directory of Open Access Journals (Sweden)

Shu Shan Du

2011-04-01

Full Text Available In our screening program for new agrochemicals from Chinese medicinal herbs and wild plants, Zanthoxylum schinifolium essential oils were found to possess strong insecticidal activity against the maize weevil Sitophilus zeamais. The essential oils of Z. schinifolium fruits and leaves were extracted via hydrodistillation and investigated by GC and GC-MS. Estragole (69.52% was the major compound of the essential oil of fresh fruits, followed by linalool (8.63% and limonene (4.34% and 94.33% of the total components were monoterpenoids. The main components of the essential oil of fresh leaves were linalool (12.94%, ar-tumerone (8.95%, limonene (6.45% and elixene (5.43% and only 50.62% were monoterpenoids. However, the essential oil from purchased fruits contained linalool (33.42%, limonene (13.66% and sabinene (5.72%, followed by estragole (4.67%, nerol (4.56% and 4-terpineol (4.27%. Estragole, linalool and sabinene were separated and purified by silica gel column chromatography and preparative thin layer chromatography, and further identified by means of physicochemical and spectrometric analysis. The essential oil from the fresh fruits (LD50 = 15.93 μg/adult possessed two times more toxicity to the insects compared with that of fresh leaves (LD50 = 35.31 μg/adult. Estragole, linalool and sabinene exhibited contact activity against S. zeamais with LD50 values of 17.63, 13.90 and 23.98 μg/adult, respectively. The essential oils of Z. schinifolium possessed strong fumigant toxicity against S. zeamais adults with LC50 values of 13.19 mg/L (fresh fruits, 24.04 mg/L (fresh leaves and 17.63 mg/L (purchased fruits. Estragole, linalool and sabinene also exhibited strong fumigant toxicity against the maize weevils with LC50 values of 14.10, 10.46 and 9.12 mg/L, respectively.

Nitrous oxide emissions from clover in the Mediterranean environment

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Iride Volpi

2016-06-01

Full Text Available Introducing nitrogen N2-fixing crops into cereal-based crop rotations reduces N-fertiliser use and may mitigate soil emissions of nitrous oxide (N2O. However, the effect of the cultivation of N2-fixing crops on N2O emissions is still not well understood. N2O from N2-fixing crops can be emitted in two ways: during biological N2 fixation itself and when legume residues are returned to the soil. A field trial was carried out on clover (Trifolium squarrosum Savi to test the role of leguminous crops on N2O emissions in the Mediterranean environment. Monitoring was performed from December 2013 to September 2014. Cumulated N-N2O fluxes were calculated for the growing season (Phase 1 and the post-harvest period (Phase 2 in order to assess the importance of each phase. Our results did not show statistically significant differences between the two phases in term of contribution to the total cumulative N-N2O emissions, in fact Phase 1 and Phase 2 accounted respectively for 43 and 57% of the total.

A synergistic aggregation pheromone component in the banana weevil Cosmopolites sordidus Germar 1824 (Coleoptera: Curculionidae).

Science.gov (United States)

Cerda, H; Mori, K; Nakayama, T; Jaffe, K

1998-01-01

Cosmopolites sordidus is an important pest on banana plantations worldwide. The chemistry of the aggregation pheromone of this insect has been recently resolved and here we present the first evidence from field trails that sordidin, a compound from the male released aggregation pheromone, attracts significant number of weevils only if host plant odors are also present. Sordidin attracts few insects when it is presented without the host plant tissue. However, the attractiveness of host plant tissue increases more than tenfold when it is presented simultaneously with sordidin in field traps. We confirm experimentally that sordidin may be used as part of a system for mass trapping and monitoring this insect.

Genetic variability of isoflavones in the USDA red clover core collection

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Graziele P. Ramos

2012-11-01

Full Text Available Red clover is one of the most utilized forage in agriculture and contains many of the isoflavones known for their human health benefits. The objectives of this study were: i to quantify, using HPLC analysis, isoflavones in 77 accessions from the USDA core collection and a Brazilian line; ii to verify possible relationships depending on their origin, improvement status or maturity type and; iii to verify the seasonal variation. The isoflavone mean contents were 29.27 µg g-1 of dry material for daidzein, 163.69 µg g-1 for genistein, 11353.29 µg g-1 for formononetin and 6568.8 µg g-1 for biochanin A. Clustering was mainly influenced by the total amount of isoflavones and partially due to maturity type, improvement status and geographic origin. The seasonal evaluation demonstrated an increase of concentration during winter, and decrease during spring. These results highlighted accessions that can be used to develop new varieties with low or high isoflavones concentration.

Response of irradiated Egyptian clover (Trifolium alexandrinum L.) to water stress

International Nuclear Information System (INIS)

Hamideldin, N; Hussein, O.S

2009-01-01

Egyptian clover (Trifolium alexandrinum L.) is one of the main leguminous forage crops in Egypt. Gamma rays represent one of the important physical activators for growth and productivity. The seed were irradiated using three doses of gamma radiation (100,200 and 300 Gy) and two levels of irrigation (10 and 20 days) after germination. Gamma radiation treatments stimulated growth criteria in normal irrigation treatment, while drought irrigation treatment stunted these criteria. The most significant dose was 100 Gy, which stimulated growth criteria, chlorophylls a , b, total chlorophyll and carotenoids in both irrigation treatments used and growth hormones under drought condition. Drought stress and gamma irradiation increase amino acid content and caused change in band concentration of esterase and peroxidase isozyme .Also, 13 protein bands appeared only in treated plant with 100 Gy under drought condition. It could be concluded that the low dose (100 Gy) of gamma irradiation release the effect of drought stress.

Disconnected quark loop contributions to nucleon observables using Nf=2 twisted clover fermions at the physical value of the light quark mass

International Nuclear Information System (INIS)

Abdel-Rehim, Abdou; Kallidonis, Christos; Koutsou, Giannis

2015-11-01

We compute the disconnected quark loops contributions entering the determination of nucleon observables, by using a N f =2 ensemble of twisted mass fermions with a clover term at a pion mass m π =133 MeV. We employ exact deflation and implement all calculations in GPUs, enabling us to achieve large statistics and a good signal.

Seleção de isolados de Beauveria bassiana patogênicos ao bicudo-do-algodoeiro Selection of isolates of Beauveria bassiana pathogenic to cotton boll weevil

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Carlos Alberto Domingues da Silva

2001-02-01

Full Text Available Objetivou-se selecionar isolados de Beauveria bassiana (Balsamo Vüillemin provenientes de diferentes hospedeiros e regiões geográficas, patogênicos ao Anthonomus grandis, o bicudo-do-algodoeiro. Foram analisados 12 isolados em condições de laboratório. Os isolados obtidos originalmente de A. grandis foram pouco virulentos a essa praga. A mortalidade do bicudo teve início no segundo dia após a inoculação das suspensões fúngicas, variando de 15% a 83%, com TL50 entre 5,30 a 11,06 dias. Os isolados apresentaram variabilidade quanto à germinação dos conídios em meio de cultura artificial, e esta não se correlacionou com a patogenicidade. O isolado CG138 de B. bassiana destacou-se como um dos mais virulentos ao bicudo-do-algodoeiro.The objective of this work was to screen pathogenic isolates of Beauveria bassiana (Balsamo Vüillemin from different hosts and geographic regions, pathogenic to the cotton boll weevil. Twelve isolates were evaluated. Isolates originally obtained from boll weevil showed low pathogenicity against this host. Insect mortality began on the second day after inoculation by fungal suspension, ranging from 15% to 83%, with a TL50 of 5.30 to 11.06 days. Variability among isolates concerning conidial germination in artificial culture medium was verified, and TG50 did not correlate with pathogenicity. One of the most virulent isolates of B. bassiana against cotton boll weevil is CG138.

Mobilization and utilization of sparingly soluble phosphates by VA mycorrhizal fungus external hyphae I-32P indirectly labelling

International Nuclear Information System (INIS)

Yao Qing; Zhao Zijuan; Feng Gu; Li Xiaolin; Chen Baodong

2000-01-01

Red clover were grown in three-compartment boxes, and were inoculated with VA mycorrhizal fungus, Glomus mosseae. External hyphae were separated from root system by 30 μm pore size membrane. Phosphorus fertilizer indirectly labelled with 32 P and five kind of phosphates were applied in the hyphae compartment, and the ability of external hyphae to mobilize the sparingly soluble phosphates were evaluated. the results showed that external hyphae mobilized and up took Ca 2 -P, Ca 8 -P, Al-P, Fe.P, but not Ca 10 -P. The phosphorus uptake by clover from phosphates and the contribution of phosphates to clover phosphorus nutrition were ranked as Ca 2 -P > Ca 8 -P, Al-P > Fe-P

Ozone and Water Stress: Effects on the Behaviour of Two White Clover Biotypes

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Massimo Fagnano

Full Text Available ozone pollution, water stress, stomata conductance, ozone uptake, clover, OTC.Ozone is a strong oxidizing pollutant which derives by alteration of the photolytic NOx cycle and it accumulates in the troposphere spreading in rural areas and therefore determining injuries on natural vegetation and crops. Since its penetration occurs mainly through stomata, all factors which alter plant-atmosphere relations could be able to modify plant response to ozone. Interaction between ozone and water stress in Mediterranean environment was studied on ozone resistant and sensitive biotypes of white clover, which were grown in charcoal filtered and notfiltered Open Top Chambers in factorial combination with different levels of water supply. Measurements of biomass, leaf area and stomatal conductance were made during the growth period. Ozone injuries were estimated as not-filtered/filtered OTC yield ratio; the stomatal flux of ozone was estimated multiplying stomata conductance x diffusivity ratio between ozone and water vapour (0.613 x ozone hourly concentrations. The hourly values of ozone uptake were cumulated throughout the cropping periods of the two years. In the sensitive biotype, water stress reduced yield losses due to ozone from 38% to 22%, as well as yield losses due to water stress were reduced by the presence of ozone from 43% to 29%, while no interaction between ozone and water stress was observed in the resistant biotype. Biomass yield losses of the sensitive biotype were strictly correlated to cumulated ozone uptake (R2 = 0.99, while biomass yield losses of the resistant biotype were not affected by the ozone fluxes variations created by the treatments. Flux based models could better estimate yield losses due to ozone in Mediterranean environments in which other stresses could be contemporary present; therefore, the new European directives might replace the actual thresholds based

Perturbative determination of c{sub sw} for plaquette and Symanzik gauge action and stout link clover fermions

Energy Technology Data Exchange (ETDEWEB)

Horsley, R. [Edinburgh Univ. (United Kingdom). School of Physics; Perlt, H.; Schiller, A. [Leipzig Univ. (Germany). Inst. fuer Theoretische Physik; Rakow, P.E.L. [Liverpool Univ. (United Kingdom). Theoretical Physics Division, Dept. of Mathematical Sicences; Schierholz, G. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

2008-06-15

Using plaquette and Symanzik improved gauge action and stout link clover fermions we determine the improvement coefficient c{sub SW} in one-loop lattice perturbation theory from the off-shell quark-quark-gluon three-point function. In addition, we compute the coefficients needed for the most general form of quark field improvement and present the one-loop result for the critical hopping parameter {kappa}{sub c}. We discuss mean field improvement for c{sub SW} and {kappa}{sub c} and the choice of the mean field coupling for the actions we have considered. (orig.)

Design and fabrication of 4π Clover Detector Array Assembly for gamma-spectroscopy studies using thermal neutrons

International Nuclear Information System (INIS)

Kumar, Manish; Kamble, S.R.; Chaudhari, A.T.; Sabharwal, T.P.; Pathak, Kavindra; Prasad, N.K.; Kinage, L.A.; Biswas, D.C.; Bhagwat, P.V.

2017-01-01

Nuclear spectroscopy has been studied earlier from the measurement of prompt gamma rays produced in reactions with thermal neutrons from CIRUS reactor. For studying the prompt γ-spectroscopy using thermal neutrons from Dhruva Reactor, BARC, the development of a dedicated beam line (R-3001) is in progress. In this beam line a detector assembly consisting of Clover Ge detectors will be used. This experimental setup will be utilized to investigate nuclear structure using prompt (n,γ) reactions and also to study the spectroscopy of neutron-rich fission-fragment nuclei

The combined effect of fertiliser nitrogen and phosphorus on herbage yield and change in soil nutrients of a grass/clover and grass-only sward

NARCIS (Netherlands)

Schils, R.L.M.; Snijders, P.J.M.

2004-01-01

The combined effect of reduced nitrogen ( N ) and phosphorus ( P ) application on the production of grass- only and grass/ clover swards was studied in a five- year cutting experiment on a marine clay soil, established on newly sown swards. Furthermore, changes in soil N, P and carbon ( C ) were

Insecticidal activity of 2-tridecanone against the cowpea weevil Callosobruchus maculatus (Coleoptera: Bruchidae

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Yussef F.B. Braga

2007-03-01

Full Text Available The effect of 2-tridecanone vapor on the cowpea weevil (Callosobruchus maculatus development was determined. Seeds of cowpea were infested with adults and exposed to different doses of 2-tridecanone isolated from Pilocarpus microphyllus Stapf ex Holm, a plant species native from northeastern Brazil. The pure monoterpene was evaluated both undiluted as well as in the dilutions 1:10, 1:100 and 1:1,000 (v/v. The following parameters of the cowpea weevil life cycle were analyzed in response to decreasing doses of 2-tridecanone: number of eggs laid, percentage of egg hatching on seeds, percentage of adult emergence, adult weight at emergence, mean developmental time and number of adults emerged. Vapor of 2-tridecanone caused a significant (P O efeito dos vapores da 2-tridecanona sobre o caruncho do feijão-de-corda (Callosobruchus maculatus foi avaliado. Sementes de feijão-de-corda infestados com insetos adultos foram expostas a diferentes doses de 2-tridecanona isolada de Pilocarpus microphyllus, uma espécie nativa do Nordeste do Brasil. O monoterpeno puro foi utilizado nas diluições 1:10, 1:100 e 1:1000 (v/v. Os parâmetros da biologia do inseto foram analisados em função da resposta a doses decrescentes de 2-tridecanona: número de ovos postos por fêmea, percentagem de eclosão de ovos, percentagem de emergência de adultos, peso dos adultos recém-emergidos, tempo médio de desenvolvimento e número total de ovos emergidos. Diferenças significativas (P < 0.05 entre as doses de 2-tridecanona testadas foram observadas, para quatro dos seis parâmetros biológicos analisados. Os resultados obtidos indicaram que a 2-tridecanona é tóxica para C. maculatus, reduzindo significativamente (P < 0.05 o número de insetos emergidos após a infestação. Esse efeito foi causado principalmente pela significativa redução observada na eclosão dos ovos expostos ao vapor da substância.

Absence of Hg transpiration by shoot after Hg uptake by roots of six terrestrial plant species

International Nuclear Information System (INIS)

Greger, Maria; Wang Yaodong; Neuschuetz, Clara

2005-01-01

In this paper we investigated if, and to what extent, six different plant species accumulate, translocate and emit mercury (Hg) into the air. The Hg uptake by roots, distribution of Hg to the shoot and release of Hg via shoots of garden pea, spring wheat, sugar beet, oil-seed rape, white clover and willow were investigated in a transpiration chamber. The airborne Hg was trapped in a Hopcalite trap or a gold trap. Traps and plant materials were analysed for content of Hg by CVAAS. The results show that all plant species were able to take up Hg to a large extent from a nutrient solution containing 200 μg L -1 Hg. However, the Hg translocation to the shoot was low (0.17-2.5%) and the Hg that reached the leaves was trapped and no release of the absorbed Hg to the air was detected. - Mercury translocation to shoots was low

Comparison of buckwheat, red clover, and purple tansy as potential surrogate plants for use in semi-field pesticide risk assessments with Bombus impatiens

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Angela E. Gradish

2016-07-01

Full Text Available Background. Bumble bees (Bombus spp. are important wild and managed pollinators. There is increased interest in incorporating data on bumble bees into risk assessments for pesticides, but standardized methods for assessing hazards of pesticides in semi-field and field settings have not yet been established for bumble bees. During semi-field studies, colonies are caged with pesticide-treated flowering surrogate plants, which must be attractive to foragers to ensure colony exposure to the test compound, and must produce an ample nectar and pollen to sustain colonies during testing. However, it is not known which plant(s are suitable for use in semi-field studies with bumble bees. Materials and Methods. We compared B. impatiens foraging activity and colony development on small plots of flowering buckwheat (Fagopyrum esculentum, var. common, red clover (Trifolium pratense, and purple tansy (Phacelia tanacetifolia under semi-field conditions to assess their suitability as surrogate plants for pesticide risk assessment studies with bumble bees. We also compared the growth characteristics and input requirements of each plant type. Results. All three plant types generally established and grew well. Red clover and purple tansy experienced significant weed pressure and/or insect pest damage. In contrast, pest pressure was extremely low in buckwheat. Overall, B. impatiens foraging activity was significantly greater on buckwheat plots than red clover or purple tansy, but plant type had no effect on number of individuals produced per colony or colony weight. Discussion. Because of the consistently high foraging activity and successful colony development observed on buckwheat plots, combined with its favourable growth characteristics and low maintenance requirements, we recommend buckwheat as a surrogate plant for use in semi-field pesticide toxicity assessments with B. impatiens.

Integrated pest management for sweetpotato in Eastern Africa

NARCIS (Netherlands)

Smit, N.

1997-01-01

Sweetpotato is an important crop in Eastern Africa. Sweetpotato weevils ( Cylas puncticollis Boheman and C. brunneus Fabricius; Coleoptera: Apionidae) cause damage to roots and vines
throughout the crop's