Co-oridinate research for breeding for virus resistance in vegetable crops

Top PDF Co-oridinate research for breeding for virus resistance in vegetable crops:

Advanced Breeding Tools in Vegetable Crops

Advanced Breeding Tools in Vegetable Crops

About 600 ha were grown commercially when NewLeaf™ cultivars were introduced in 1995 in Pacific Northwest US, and the commercial acreage reached rapidly about 20,000 ha in 1998 because they quickly became popular among growers since the product was very effective at preventing CPB damage. Market success of the NewLeaf™, NewLeafY™, and NewLeafPlus™ potatoes could be attributed to the difficulty in controlling CPB, in regions like Pacific Northwest with mild winters, where CPB was a problem, and also where there are high pest populations of aphids associated with virus problems [18]. This virus resistance benefited seed producers, while commercial growers benefited from higher yields and reduced need for insecticides [18]. The reported profits in USA were on average US$ 55 ha -1 for Bt- potato [19]. Likewise, an ex-ante analysis suggested an average profit of US$ 117 ha -1 for virus-resistant potato in Mexico [20]. The processing industry and consumers benefited from improved quality. Potatoes were one of the first foods from a transgenic crop that was commonly served in restaurants. NewLeaf™ potato cultivars were the fastest cultivar adoption in the history of the USA potato industry [18], until potato processors, concerned about anti-biotech organizations, consumer resistance and loss of market share in Europe and Japan, suspended contracts for Bt-potatoes with growers in 2000 [21]. The North American fresh market continued to accept transgenic potatoes, but with processed potato markets closing growers became reluctant to take on the risk of planting biotech potatoes [22]. The major impact came when the leading fast food McDonald‘s chain, concerned about anti-biotech organizations, decided to ban transgenic potatoes from its servings. Surrendering to dwindling marketability for their products, Monsanto closed its NatureMark potato business in the Spring of 2001 [22].
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Advances in Transgenic Vegetable and Fruit Breeding

Advances in Transgenic Vegetable and Fruit Breeding

There are few sources of natural resistance to Plum pox virus (PPV), the causative agent of Sharka, one of the worldwide most destructive diseases of plum and other stone fruits. Over the past 20 years an intensive interna- tional research project between USA, France, Poland, Romania, Spain, and Czech Republic has focused on the development of transgenic resistance to PPV [64]. The PPV coat protein (CP) gene was isolated, sequenced, and cloned by Ravelonandro et al. [65] and was used for Agrobacterium-mediated transformation of plum. This gene was transferred to plum through genetic engineering. As a result, the highly PPV-resistant cultivar “Honey Sweet” plum was bred. This cultivar has shown its host plant resistance after 15 years of field testing in Europe under heavy infection pressure [66]-[68] and in greenhouse tests in the USA (since field inoculations were not allowed because PPV was not in this country until 1999, and is still a quarantine organism under a containment and era- dication program). Its transgenic resistance was further transferred to other seedlings through crossbreeding [69] [70], thus developing additional PPV-resistant cultivars. The efficacy and safety of “Honey Sweet” was assessed through laboratory, greenhouse and field research during 12 years, which led to the regulatory approval of this PPV resistant transgenic plum cultivar in the USA in 2011. “Honey Sweet” is the culmination of years of research and development. In anticipation of the potential spread of PPV to other US regions, breeding with “Honey Sweet” is underway to transfer the PPV resistance transgene into new cultivars adapted to different US growing locations. Breeding with “Honey Sweet” is relatively rapid since an easy molecular marker assay provides means for de- tecting its resistance transgene in “Honey Sweet” derived-seedlings. This resistance is transferred to the offspring as a single dominant gene. The transgene resistance technology and post-transcriptional gene silencing tested in “Honey Sweet” can be used to develop other resistant stone fruits, such as peach, apricot, Japanese plum, and cherry, which are susceptible to PPV. Studies show that “Honey Sweet” plum fruit quality is excellent, and pro- ductivity is very good [64]. The international collaborative program that bred “Honey Sweet” shows the potential of public funding for research and development, which provides safe, efficacious genetic engineering products for the benefit of growers and consumers. “Honey Sweet” plum provides an interesting germplasm source for PPV control elsewhere.
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Molecular markers and their application in improvement of vegetable crops

Molecular markers and their application in improvement of vegetable crops

There are mainly two types of molecular markers i.e. Hybridization based or Non-PCR based marker for example Restriction Fragment Length Polymorphism (RFLP) (Botstein et al. 1980). Polymerase chain reaction (PCR) based markers example Random Amplified Polymorphic DNA (RAPD) (Williams et al., 1990), Sequence characterized amplified regions (SCARs) (Michelmore et al., 1991) and Amplified Fragment Length Polymorphism (AFLP) (Vos et al., 1995). Molecular markers are used for development of saturated genetic maps; DNA fingerprinting; Phylogenetic and evolutionary studies; heterotic breeding; gene tagging and marker assisted selection (MAS). Identification of vegetable crop varieties by molecular markers in tomato (Noli et al., 1999), Potato (Ashkenazi et al., 2001), Onion, garlic and related species (Fischer and Bachmann 2000). Molecular markers are linked to major disease resistance in tomato like Meloidogyne incognita (Williamson et al., 1994) and Tomato mosaic virus (Sobir et al., 2000).
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Breeding Cultivars for Heat Stress Tolerance in Staple

Food Crops

Breeding Cultivars for Heat Stress Tolerance in Staple Food Crops

before the onset of heat stress. In durum wheat, this property has been utilized in develop- ment of early maturing genotypes such as Waha-1, Omrabi-5, and Massara-1 [119]. In rice, introgression breeding has facilitated the transfer of HT from “N22” to “Xieqingzao B” line by developing BC 1 F 8 lines [120]. Additionally, the advanced line derived from Gayabyeo/ N22 cross has ofered HT as well as high yield [121]. In wheat, Aegilops tauschii was suc- cessfully used as a donor for incorporating HT-relevant component traits such as cell mem- brane stability and chlorophyll retention into cv. PBW550 through backcrossing [122]. More recently, atempts were made in wheat aiming at introgression of wheat-Leymus racemosus chromosome to cv. Chinese spring to enhance HT and beter adaptation under heat stress [123]. Impressive accomplishments were achieved in harnessing the natural genetic variation for HT, and additional eforts are underway to introduce the heat tolerance QTLs/genes into diferent genetic backgrounds [88, 120]. In coton, through pollen selection under HS, heat tolerance genes were transferred from a donor line “7456” (G. barbadense L.) to a heat-sensitive genotype “Paymaster 404” through backcrossing [113]. In sunlower, by using temperature induction response (TIR) technique, adequate genetic variability was observed for thermotol- erance among the parental lines of the hybrid KBSH-1, viz. CMS234A, CMS234B, and 6D-1 [124]. The availability of potential donors for HT would encourage plant breeders not only to deploy these novel sources directly in breeding schemes but also to excavate the resilient alleles that underlie tolerance.
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Reaction of wheat varieties to infection with barley yellow dwarf virus and prospects for resistance breeding

Reaction of wheat varieties to infection with barley yellow dwarf virus and prospects for resistance breeding

Abstract: The reaction of winter and spring wheat to infection with barley yellow dwarf virus (BYDV-PAV) was evaluated in three-year small-plot field trials on 71 wheat varieties registered in the Czech Republic and at two locations for two years on 63 selected potential sources of resistance. Disease symptoms (VSS) were visu- ally recorded using a 0–9 scale and the percent reduction of grain weight per spike (GWS-R) was measured on twenty plants per plot. The evaluation showed that among the registered varieties of winter and spring wheat no variety had a high resistance to BYDV (with VSS lower than 3.5). GWS-R ranged between 24% and 60%. Higher variability in VSS was detected for the registered varieties of spring wheat compared to winter wheat. Among the registered varieties of winter wheat, Saskia, Rialto, Meritto, Rexia, and Svitava, as well as the spring wheat Leguan, received the best long-term evaluations. The highest level of resistance was detected for the PSR 3628 line (a hybrid of wheat and couch-grass), but in connection with a low agronomic value. The WKL91-138 line of spring wheat and some varieties (lines) with the detected moderate level of resistance, in particular, could offer good prospects for use in breeding. The presence of the Bdv2 gene was expressed only in the reduction of virus content on the 11 th day after inoculation. Nevertheless, genotypes carrying this gene were evaluated in
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Rootstock breeding for abiotic stress tolerance in fruit crops

Rootstock breeding for abiotic stress tolerance in fruit crops

Mango (Mangifera indica L.) is one of the most important fruit crops all over the world, especially in tropical and subtropical regions. For increasing productivity of mango, the production from existing area needs to be increased, but at the same time, new areas also need to be brought under cultivation with enhanced fruit production. One of the major limitations for extensive cultivation of mango is abiotic stresses particularly soil salinity, which leads to reduction in plant growth and death afterwards (Maas 1986). Mango being perennial fruit crop, is subjected to several biotic stresses like pests and diseases and abiotic stresses like soil and environmental factors. The variability among the cultivars being very high, there is always scope for locating a source of resistance. The polyembryonic cultivars, for which variability is less and which are generally seen in regions of high rainfall should be screened for these stresses. The focus of rootstock in mango includes development of genotypes that could confer resistant to adverse soil conditions and affect vigour of the scion. The other aspects include polyembryony for uniformity, dwarfing characters for establishing HDP systems, tolerance to calcareous soils, tolerance to soil borne problems
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Market access for vegetable crops : Focus on the production and evolution of vegetable prices in Lubumbashi in DR Congo

Market access for vegetable crops : Focus on the production and evolution of vegetable prices in Lubumbashi in DR Congo

A BSTRACT : This study reports the results of research on the production and marketing of market gardening in Lubumbashi. The approach used is the analysis of the situation by comparing the level of production, that is to say the crop yields with the flow of prices observed on the market during a period of 12 months spread over two years, from September 2018 to August 2019. From these results, it appears that the areas allocated to market garden crops are small: between a maximum of 0.1 ha per member in associations and 0.8 ha for farmers. The average yields obtained on all the crops concerned vary between 12.3 tons of pepper per hectare in an association against 13.5 tons per hectare on a farm and 33.4 tons per hectare of cabbage in an association against 37.7 tons per hectare in a farm. In addition, market gardening is mostly seasonal in the different sites: more intense in the dry season. On the market, demand for vegetables is permanent over time with peak periods in the rainy season, between November and February. The potato is the product that sells best, its price varies between 1810.5 Congolese Francs and 3143.4 Congolese Francs per kg, while the cabbage has the lowest price of a kg which has varied between 950 and 985 Congolese francs during the observation periode.
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Legume breeding for broomrape resistance

Legume breeding for broomrape resistance

Additional resistance mechanisms might operate after haustoria formation preventing or retarding further development into a broomrape shoot. This can result in the darkening and necrosis of tubercles as seen in vetch, faba bean, pea, chickpea, lentil and chickling vetch (Goldwasser et al. 1997; Ru- biales et al. 2003c, 2004; Pérez-de-Luque et al. 2005b; Fernández-Aparicio et al. 2008b, c, 2009c; Fernández-Aparicio & Rubiales 2010, 2012). The darkening and subsequent death of O. crenata tubercles have been ascribed to the accumulation of substances inside host xylem vessels (Pérez- de-Luque et al. 2005b, 2006b). These substances seem to block the normal flux of water and nutrients between the host and the parasite and the tubercles die after exhausting their reserves. However, other mechanisms should not be discarded, such as the production by the host and delivery into the para- site of toxic metabolites (phenolics), as described in M. truncatula–O. crenata interaction (Lozano et al. 2007).
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Field Crops Research

Field Crops Research

2017 and 2018. All plots were seeded when moisture conditions were appropriate with two passes of a 3-m wide Seed Hawk air drill (Langbank, SK, Canada) in all years. Openers are a modified, ultra- narrow knife-type on 30 cm row spacing. The drill has a piston pump for metering liquid fertilizer in direct relation to ground speed through a ground drive system. Fertilizer was banded at seeding about 5 cm below and to the side of the seed row as a solution of 79% urea-am- monium nitrate and 21% ammonium thiosulfate to give rates of 61 kg N ha −1 and 12 kg S ha −1 (0.79 kg of product in 167 l ha −1 ). University guidelines for N fertility were based on expected yields and pre-plant nitrate soil tests ( Wysocki et al., 2007 ). Nitrogen fertilizer rates for winter wheat were increased over the recommended rate suggested by fall samples to compensate for winter precipitation moving nitrate deeper in the soil profile. For spring barley and spring carinata, the N application rate recommended was also increased to compensate for immobilization, due to high straw levels of previous winter wheat that temporarily reduces the amount of available N in the soil. Given the direction of these adjustments, the N applied to these winter and spring crops was the same. Harvest of W and B plots was performed using a Wintersteiger Delta combine with a top sieve of 9–10 mm in mid-July except B in 2017 that was 31 July. Carinata plots were harvested with the same machine at physiological maturity but using a top sieve of 5 mm.
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Pesticide Use in Vegetable Crops: Frequency, Intensity and Determinant Factors

Pesticide Use in Vegetable Crops: Frequency, Intensity and Determinant Factors

7 to Rs 26 by managing huge losses on crops like cotton, paddy, sugarcane, sunflower, mustard, vegetables and groundnut (Bakhetia and Udean, 1998). Excessive and indiscriminate use of pesticides not only increases the cost of production but also results in many human health problems and environmental pollution. According to WHO estimates, one million cases of pesticide poisoning occur every year and consequently there are 20,000 deaths globally (Nasir, 1999). The most damaging ecological disturbance of injudicious use of pesticides is the existence of high concentration of pesticide residues in food chain, including cereals, pulses, vegetables, fruits, milk and milk products (including mother’s milk), fishes, poultry, meat products and water.
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Effect of Vermicompost on Growth, Yield and Quality of Vegetable Crops

Effect of Vermicompost on Growth, Yield and Quality of Vegetable Crops

Along with these issues, increasing demands for fuel crops for sustaining the rapidly growing economies is needed. According to the estimates of UN population projection, world population could reach 9.15 billion by 2050, thus the expected rate of increase in world population will be 2.25 percent over the next forty years. However, recent research work into the effects of vermicompost utilization on vegetables crop, have been very limited. In the present review paper the main objectives are to investigation the effects of vermicompost applications on the growth, yield and quality of vegetable crops.
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PHYTONEMATODES GROWTH EFFECT STUDIES ON LEAFY VEGETABLE CROPS

PHYTONEMATODES GROWTH EFFECT STUDIES ON LEAFY VEGETABLE CROPS

Nematodes feed from plants in a variety of ways, but all use a specialized spear called a stylet. In this work, we have identified several nematodes in the soil of leafy vegetable crops like Spinach and Mentha. The nematodes Radopholus and Criconemella were specific in Spinach soil and Rotylenchulus was specific in Mentha. Soil analysis of these vegetable crops was studied and the pH was found to be 7.5 in spinach grown soil and 7.8 in mentha grown soil. The temperature was found to be 25 0 C for spinach soil, and 25 0 C for Mentha soil. Among the soils selected, Spinach showed high diversity of microorganisms followed by Mentha. Micrococcus roseus, Bacillus cereus, Cellulomonas terrae, Pseudomonas fluorescens, Azospirillum brasilense, Rhizopus microspores, Aspergillus niger, Curvularia clavata, Fusarium oxysporum, Penicillium chrysogenum and AM Spore were found in all the different soils of leafy vegetables. Hoplolaimus was found to be in low number and Aorolaimus was found to be in high number in leafy vegetables. The nematode population density was increased from first day to 30 th day in all the leafy vegetable crops. When compared to control (without leafy vegetables), the soil which contain with leafy vegetables have high nematode number.
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Transgenic Bt crops and resistance..

Transgenic Bt crops and resistance..

One reason resistance could develop is that the transgenic cotton and corn varieties currently marketed each produce only one toxic Bt protein, compared to the principal Bt strain used i[r]

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Transgenic Vegetable Breeding for Nutritional Quality and Health Benefits

Transgenic Vegetable Breeding for Nutritional Quality and Health Benefits

Another approach to improving the health functionality of vegetable crops is to reduce the concentration of anti- nutritional factors. These are naturally occurring com- pounds with inhibitory effects on the nutritive potential of plants. In many cases, anti-nutritional factors are pro- duced in planta for pest control, but have secondary ef- fects on human nutrition. The first transgenic cassava plants became available in the mid-1990s [56-58] as plants with reduced cyanogenic content [59-61], which can benefit resource-poor people in rural Africa where this starchy root crop is the base of their diet. Faba bean (Vicia faba) contains condensed tannins that reduce the value of the inherently high protein levels of the crop. Tannins can be removed by the activity of two genes, zt-1 and zt-2, which are pleiotropic for white-flowered plants. Gutierrez, et al. [62] have identified a sequence characterized amplified repeat (SCAR) marker linked to the zt-2 gene that is as- sociated with increased protein levels and reduced fibre content of faba bean seeds, which should facilitate the development of tannin-free faba cultivars. Calcium oxalate is another common anti-nutritional factor in plants. It is most commonly found as deposits in the vacuole of spe- cialized cells called idioblasts [63]. The specific function of calcium oxalate accumulation in plants is not known; it might have a role in calcium regulation, ion balance, plant protection, detoxification or light gathering. There have been several attempts to reduce the amount of cal- cium oxalate in plant tissues by using molecular approaches. Nakata and McConn [64] identified mutants of barrel clover (Medicago truncatula) that are deficient in calcium oxalate and not compromised in growth. This suggests that it might be possible to genetically engineer plants with low or very low calcium oxalate levels; however, if calcium oxalate has a role in plant protection, low-calcium oxalate crops would require other protection strategies.
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Integration of summer and fall cover crops in vegetable cropping systems

Integration of summer and fall cover crops in vegetable cropping systems

Much of the research focusing on cover crops in Iowa has been conducted in row crops. What is not well understood is how cover crops can influence vegetable crop production in Iowa. There are obvious reasons as to why this void in research exists. In Iowa there are only 7,724 acres of commercial vegetable production (U.S. Department of Agriculture, 2014) but research is needed about the integration of cover crops in Iowa vegetable production. According to the Leopold Center for Sustainable Agriculture (2012) and Lucht (2015) the demand for locally grown food is growing in Iowa. Even at a national scale, local foods have had an increase in demand (Doering, 2015). More research in needed to study effects of cover crops on soil properties and environmental aspects such as nitrogen leaching, and crop growth, development, and yield. Within the U.S. a number of studies have been conducted in states such as California (Wang et al., 2008a; Wyland et al., 1996), Michigan (Wang et al., 2008b), New York (Bjoerkman et al., 2015), and North Carolina (Finney et al., 2009), on cover crops for vegetable crop systems. Locations outside U.S. have also been investigating the effects of cover crops on following vegetable crops such as Australia (Little et al., 2004) and Italy (Campiglia et al., 2009). Although these studies provide valuable information on benefits of cover crops in vegetable systems, more research is needed on cover crops under Iowa growing
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Eco-Friendly Biocontrol Measures for Xanthomonas Infection on Vegetable Crops

Eco-Friendly Biocontrol Measures for Xanthomonas Infection on Vegetable Crops

Pathovars of Xanthomonas are known to cause diseases on several vegetable and cash crops and are reported to have developed resistance to kanamycin, ampicillin, penicillin and streptomycin. This seriously hinders the management of diseases of crops and agriculture products. To control these bacteria farmers used many synthetic pesticides. But pesticides have made great contribution for quick and effective management of plant diseases and microbial contaminations in several agricultural commodities. Many Xanthomonas Pathovars have acquired resistance to synthetic pesticides. Considering the deleterious effects of synthetic pesticides on life supporting system, there is an urgent need for alternative agents for the management of pathogenic microorganisms. Hence the present study focused to control the phyto pathogen in eco friendly method using green plant extracts. Different parts of a medicinal
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Identification of insects, spiders and mites in vegetable crops: Trainer's handbook

Identification of insects, spiders and mites in vegetable crops: Trainer's handbook

The training process was further refined for a train-the-trainer course ‘Extension tools for IPM in vegetable crops’ held in Hangzhou, China in 1999 as part of ACIAR project PN9213 ‘Improving pest management in brassica vegetable crops in China and Australia’. We also gratefully acknowledge the role of the Rural Extension Centre (Gatton, Queensland) in shaping our approach to training and extension practice. We would like, in particular, to thank Iain Kay (Senior Entomologist, DEEDI), Deborah Atkins (Senior Training Officer, CRC for Irrigation Futures), Cindy Benjamin (Information Extension Officer, DEEDI), Danielle Jones (Editor, DEEDI) and Matt Curr (Graphic Designer, DEEDI) for their constructive comments, practical suggestions and editorial/design assistance with the production of this handbook.
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Utilization of Urine for Cultivation of Selected Vegetable Crops in Backyard “Peeponics”

Utilization of Urine for Cultivation of Selected Vegetable Crops in Backyard “Peeponics”

The study revealed that the nitrogen level of diluted urine on 1:35 and 1:45 dilution ratios that supported Amaranthus viridis cultivation was reduced by 38.5% and 59.9% respectively at the end of the experiment. The phosphorus de- creased by 49.1% in 1:35 dilution; and 100% in 1:45 dilution. The potassium re- duced by 37.6% in 1:35 dilution; and 55.3% in 1:45 dilution. All the nutrients in the control were completely exhausted at the end of the experiment. These downward trends indicate nutrient clearance from the soilless medium which was caused by the absorption of the test plant. Similar increase in agronomy pa- rameters which leads to decrease in NPK has been reported [27] [30]. The pro- portion of nitrogen reduction of Corchorus olitorius vegetable was 87.2% with UDR 1:45 compared to 52.9% with UDR 1:35. Phosphorous reduction of Cor- chorus olitorius vegetable on UDR 1:45 and 1:35 were 100% and 56.6% respec- tively, whereas potassium was reduced by 86.1% at a UDR 1:45 and 64.2% at a UDR 1:35. However, the total nutrients (NPK) reduction (100.0%) was observed in the two vegetables ( Amaranthus viridis and Corchorus olitorius ) cultivated on the control water. These findings corroborate the report of Morgan and Con- nolly [31] that plant growth and development largely depend on the combina- tion and concentration of mineral nutrients available in the soil or the medium, in this case liquid.
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Application of Molecular Tools in Breeding Cereal Crops for Drought Tolerance

Application of Molecular Tools in Breeding Cereal Crops for Drought Tolerance

Genome-wide selection (GWS) or genomic selection (GS) is another important approach to develop superior germplasm lines with overall excellent performance in a target environment. Genome-wide marker genotyping is used for GWS rather than selected markers showing significant associations (as in case of MARS) with the traits of interest. In summary, individuals in a phenotyped population (generally referred to as the ‘training population’) are genotyped using genome-wide markers and breeding values of alternative alleles of all the markers are fitted as random effects in a linear model. Individuals in subsequent recurrent selection generations are then selected based purely on the sum of those breeding values [genomic estimated breeding value (GEBV)]. Therefore, GWS reduces the frequency of phenotyping and similarly also increases annual gains from selection by reducing cycle time (Rutkoski etal., 2010). Several groups have recently started exploring the GWS approach in both self- and cross-pollinated crops with some modifications for both types of crops (Bernardo, 2010). The success of the GWS approach is dependent on the availability of a diverse and representative training population. Furthermore, the phenotyping of the training population is crucial and additional lines should be integrated over time to increase the effectiveness and relevance of the gene effect estimates.
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Integrated control of slug damage in organic vegetable crops  OF 0158

Integrated control of slug damage in organic vegetable crops OF 0158

• The carabid beetle, Pterostichus melanarius, did not appear to be effective in preventing contamination of cabbages by slugs at harvest in September, even though the crop had been grown in the field throughout the beetles’ main period of activity. Numbers of adult P. melanarius are thought to be drastically reduced by ploughing and associated cultivations in spring, compared with autumn cultivation (Purves, 1996). This is because ploughing in spring is thought to result in high mortality of the beetle, which is present as pupae in the soil in spring. Since soil is normally cultivated in spring before planting most organic vegetable crops that are grown over the summer, during the period of P. melanarius activity, this probably prevents beetles from reaching high numbers in most such crops. However, even in a field experiment where large numbers of beetles were introduced to a summer cabbage crop, P. melanarius had no significant effect on the contamination of cabbage heads by slugs. Interestingly, Symondson (1993b) concluded that although a related carabid beetle, Abax parallelepipedus, was an effective predator of slugs at soil level, it was incapable of capturing slugs within large lettuce plants. Similarly, in the cabbage experiment in OF0158, slugs may have used the cabbage heads as refuges from beetle predation.
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