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Sugarcane is an important crop in Pakistan and this crop usually affected by insect pest. Among these insect pests in sugarcane, borers are very dangerous, (Lepidoptera: Pyralidae) whereas Trichogramma chilonis Ishii. (Hymenoptera: Trichogrammatidae) is prominent egg parasitoid utilized for the purpose of borers attack in IPM. This research was carried-out for the purpose of success various issuance of T.chilions in case of sugarcane insect attacks and observe the decay rate of sugarcane borers and such as control issuance by T. chilonis egg cards. The borers' generation emerges out after 27 days, trichogramma cards T. chillions were installed with the duration after 10, 15, 20, days interval repeated and to check out infestation of sugar cane borers. The research shows that results of installed crop was excellent minimum borer attack as compared to less installed trichogramma card. More treated with trichogramma card about 60000 parasitoids eggs /acre at interval after 20 days repeat from May to August. While borers complete their life cycle 30-35 days. This study shows that treated with biological control plot significantly decrease borers infestation as contrast to the less tricho gramma card used. It is very cheap and fully control as well as co-friendly, no effect on the crop stress as compared to the pesticides application. To increase the quality about 0.2-0.5 in sugarcane recovery and more than 150-200 mound per acre increases due to application of trichogramma cards. Whole minimum to high amount of trichogramma cards T3 600000 parasitoids eggs/acre growth was 42.07 note max high yield 35.51 ton/ha and more brix 20.1 were seen. The results showed that T. chilonis eggs card is successful and inexpensive and environmental safe recruitment for complete dominating over sugarcane borers. [ABSTRACT FROM AUTHOR]

Two stem-boring moths, the yellow stemborer (YSB) Scirpophaga incertulas (Walker), and the striped stemborer (SSB), Chilo suppressalis (Walker), damage rice in Asia. YSB is the dominant species in much of tropical Asia. Both species are oligophagous on domesticated and wild rice. We investigated the roles of host plant preferences and larval performance in determining the larval densities of both species in rice plots. In screenhouse experiments, YSB showed significant preference–performance coupling. Adults preferred high-tillering rice varieties during early vegetative growth. In contrast, SSB did not demonstrate oviposition preferences under the same screenhouse conditions, but did oviposit less on the wild rice Oryza rufipogon Griff. than on domesticated rice varieties during a choice experiment. Despite differences in preference–performance coupling, larval survival and biomass across 10 varieties were correlated between the two species. YSB and SSB larvae occurred in relatively high numbers on rice varieties with large tillers (IR70, IR68, and T16) in wet and dry season field experiments. However, whereas YSB was the dominant species on IR68 and IR70, it was relatively less abundant on T16, where SSB dominated. Results suggest that YSB preferentially attacked fast-growing rice varieties with high tiller numbers early in the crop cycle. Meanwhile SSB, which has weak preference–performance coupling, occurred in rice plants with large tillers that were relatively free of YSB later in the crop cycle. These factors may allow the species to coexist. We discuss the implications of proximate and ultimate factors influencing stemborer co-occurrence for the sustainable production of rice in tropical Asia. [ABSTRACT FROM AUTHOR]

Because of variation in incidence and severity of damage by Chilo partellus (Swinhoe) in different geographical regions, it is difficult to identify stable sources of resistance against this pest. Therefore, the present studies were undertaken on biological attributes (damage in resistant and susceptible genotypes, survival and development) and biochemical profiles (amino acids and lipophilic compound) of C. partellus populations from eight geographical regions to understand it's population structure in India. There was a significant variation in biological attributes and biochemical profiles of C. partellus populations from different geographical regions. Based on virulence and biological attributes, similarity index placed the C. partellus populations in five groups. Likewise, lipophilic and amino acid profiling also placed the C. partellus populations in five groups. However, the different clusters based on biological and biochemical attributes did not include populations from the same regions. Similarity index based on virulence, biological attributes, and amino acids and lipophilic profiles placed the C. partellus populations in six groups. The C. partellus populations from Hisar, Hyderabad, Parbhani and Coimbatore were distinct from each other, indicating that there are four biotypes of C. partellus in India. The results suggested that sorghum and maize genotypes need to be tested against these four populations to identify stable sources of resistance. However, there is a need for further studies to establish the restriction in gene flow through molecular approaches across geographical regions to establish the distinctiveness of different biotypes of C. partellus in India. [ABSTRACT FROM AUTHOR]

Invasion of crops by stemborers previously known in natural vegetation only requires close monitoring for early detection of stemborer exchange between the habitats. This in turn demands up-to-date knowledge about the diversity of stemborers in natural habitats. The current list of known stemborers in South Africa includes 49 species associated with 65 wild host plant. The Eastern Cape and KwaZulu-Natal biogeographic regions received little coverage in earlier studies. This study sought to fill this knowledge gap. We conducted surveys from 14 November 2014 to 18March 2015 in the Eastern Cape and KwaZulu-Natal biogeographic regions. Potential host plants in families Poaceae, Cyperaceae, and Typhaceae were dissected in the field, stemborer life stages collected, reared on artificial diet, and identified to the lowest possible taxonomic level. Thirty-three species belonging to Crambidae, Noctuidae, Phycitidae, Pyralidae and Tortricidae were recovered from27 host plant species. Twenty-four species were recorded in Eastern Cape and 28 species in KwaZulu-Natal. The Chao 1 asymptotic species richness estimator predicted 3 and 5 more species for the biogeographic regions indicating an equitably complete species inventory of the study area. Fifteen species collected in this study are part of the existing inventory, and 19 are first records on the various host plants. The new records expand the list of stemborer species in South Africa from 49 to 68. The main factors influencing diversity were endemism, the number and disproportionate abundance of common and rare species. [ABSTRACT FROM AUTHOR]

The stem borer Chilo partellus (Swinhoe) is the most devastating pest that causes huge losses to agricultural productivity. Being a herbivorous insect, the starch degrading enzyme, salivary amylase, plays a crucial role in its digestive system. The characterization of salivary amylase and targeting it with potent inhibitors could help in managing the pest by hindering its normal digestive process. Therefore, we have made an attempt to characterize the enzyme and analyze its nature of interaction with organic acids and inorganic salts. The salivary amylase was purified by G-100 column chromatography to 16.02 folds and biochemically characterized. The purified fraction consisted of a-amylase activity with a single isoform of 59.26 kDa. It showed an optimum pH between 6.0 and 7.0. Its optimum temperature was 40 °C and was thermally stable up to 70 °C. Starch was the preferred substrate of salivary amylase. By critical analysis of Lineweaver-Burk, Eadie-Hofstee and Hanes plots, the Km and Vmax values of salivary amylase for starch were confirmed to be 0.49 mg/mL and 1.67 nmoles of reducing sugars formed/min/mL, respectively. Zinc chloride, calcium nitrate, salicylic acid, citric acid and oxalic acid were found to be potent inhibitors of salivary a-amylase activity. From Lineweaver-Burk, fractional velocity and combination plots, it was inferred that citric acid was a pure non-competitive inhibitor of salivary a-amylase while salicylic acid, oxalic acid and zinc chloride caused complete mixed non-competitive-competitive inhibitions. The inhibition of salivary a-amylase with calcium nitrate was of complete mixed non-competitive-uncompetitive type. [ABSTRACT FROM AUTHOR]

ساقه‌خوارها شایع‌ترین و مهم‌ترین آفاتی هستند که برنج را در طول دوران رشد مورد حمله قرار می‌دهند. در این پژوهش، پراکنش جغرافیایی شب‌پره‌های ساقه‌خوار برنج متعلق به خانواده‌های ‌Crambidae و Noctuidae در 16 استان برنج‌ کاری کشور در سال‌های 1394 و 1395 بررسی شد. جمع‌آوری حشرات کامل ساقه‌خوار به کمک تله‌ها‌ی نوری، مالایز و فرومونی انجام شد. در شالیزارهای کشور در مجموع شش گونه ساقه‌خوار شامل پنج گونه‌‌ی Chilo partellus، C. luteellus، C. suppressalis، C. phragmitella و Scirpophaga praelata از خانواده‌ی Crambidae و گونه‌ی Sesamia sp. از خانواده‌ی Noctuidae شناسایی شدند‌‌. در بین این گونه‌ها، ساقه‌خوار نواری برنج (C. suppressalis) و گونه‌ای از جنس سزامیا (Sesamia sp.) به عنوان مهم‌ترین آفات ساقه‌خوار برنج در کشور معرفی می‌شوند. طبق نتایج، حضور ساقه‌خوار نواری برنج از پنج استان خراسان رضوی، قزوین، زنجان، چهارمحال و بختیاری و آذربایجان شرقی و خسارت سزامیا روی برنج از چهار استان کهگیلویه و بویراحمد، اصفهان، ایلام و اردبیل برای اولین بار گزارش می‌شود. با توجه به نتایج این پژوهش و عدم دسترسی به نمونه‌ی تیپ، گزارش قبلی مبنی بر حضور ساقه‌خوار سفید برنج (Scirpophaga innotata) در ایران، مشکوک است. یافته‌های این پژوهش اطلاعات اولیه‌ و کلیدی درباره‌ی سطح پراکنش هر کدام از شش گونه ساقه‌خوار فعال در شالیزارهای ایران را فراهم می‌کند که می‌تواند ضرورت تجدید نظر در ارایه‌ی شیوه‌های مدیریت آن‌ها را متذکر شود. ساقه‌خوارها شایع‌ترین و مهم‌ترین آفاتی هستند که برنج را در طول دوران رشد مورد حمله قرار می‌دهند. در این پژوهش، پراکنش جغرافیایی شب‌پره‌های ساقه‌خوار برنج متعلق به خانواده‌های ‌Crambidae و Noctuidae در 16 استان برنج‌ کاری کشور در سال‌های 1394 و 1395 بررسی شد. جمع‌آوری حشرات کامل ساقه‌خوار به کمک تله‌ها‌ی نوری، مالایز و فرومونی انجام شد. در شالیزارهای کشور در مجموع شش گونه ساقه‌خوار شامل پنج گونه‌‌ی Chilo partellus، C. luteellus، C. suppressalis، C. phragmitella و Scirpophaga praelata از خانواده‌ی Crambidae و گونه‌ی Sesamia sp. از خانواده‌ی Noctuidae شناسایی شدند‌‌. در بین این گونه‌ها، ساقه‌خوار نواری برنج (C. suppressalis) و گونه‌ای از جنس سزامیا (Sesamia sp.) به عنوان مهم‌ترین آفات ساقه‌خوار برنج در کشور معرفی می‌شوند. طبق نتایج، حضور ساقه‌خوار نواری برنج از پنج استان خراسان رضوی، قزوین، زنجان، چهارمحال و بختیاری و آذربایجان شرقی و خسارت سزامیا روی برنج از چهار استان کهگیلویه و بویراحمد، اصفهان، ایلام و اردبیل برای اولین بار گزارش می‌شود. با توجه به نتایج این پژوهش و عدم دسترسی به نمونه‌ی تیپ، گزارش قبلی مبنی بر حضور ساقه‌خوار سفید برنج (Scirpophaga innotata) در ایران، مشکوک است. یافته‌های این پژوهش اطلاعات اولیه‌ و کلیدی درباره‌ی سطح پراکنش هر کدام از شش گونه ساقه‌خوار فعال در شالیزارهای ایران را فراهم می‌کند که می‌تواند ضرورت تجدید نظر در ارایه‌ی شیوه‌های مدیریت آن‌ها را متذکر شود.

The incidence of egg and larval parasitoids of Chilo partellus was monitored in insecticide free maize fields at the Indian Agricultural Research Institute, New Delhi, for three Kharif seasons of 2013 to 2015. The hymenopteran parasitoid, Trichogramma sp. was recorded to be the only egg parasitoid in this area, while a good number of larvae were parasitized by braconid, Cotesia flavipes. The egg parasitism was recorded on the freshly laid eggs of stem borer obtained by artificially releasing the adults of C. partellus on maize cultivars, HQPM1 and PMH1, at 12 days after germination. There was no egg parasitism recorded during Kharif 2013 and 2014, whereas 5.6 percent egg-mass parasitism by Trichogramma sp. was recorded during Kharif, 2015. The larval parasitoids were monitored by artificially infesting the maize plants with neonates of laboratory reared C. partellus. The larvae were allowed to develop on maize plants under field conditions for 20 days. The plants showing stem borer damage were cut and brought to the laboratory. The larvae collected from infested maize plants were reared in the laboratory. The maggots of C. flavipes recovered from parasitized larvae ranged from 29-100, 41-50 and 20-80 percent during Kharif 2013, 2014 and 2015, respectively. The result of this study indicated that parasitism by Cotesia was influenced by age of plants damaged by C. partellus. The young maize plants seemed to be more attractive to the foraging of Cotesia and more stem borer larvae were parasitized on these plants as the maximum (58 percent) parasitism was observed at 40-day-old crop. The parasitoid was found to be active on maize from 40-60 days after germination and the incidence decreased thereafter. Insecticides should not be used during this period. The current studies also revealed that host densities had no significant effect on percentage parasitism by Cotesia. [ABSTRACT FROM AUTHOR]

Studies on population dynamics and effect of temperature on the incidence of ESB were carried out during 2016-18 at ARS Sankeshwar. Two varieties viz., Co-86032 and Snk07680 were sown during two consecutive years and allowed natural infestation without taking any control measures. Activity of pest stared from 50 days after planting and the average larval population ranged from 0.5-2.00 per cane during course of investigation. The peak incidence of 1.80 mean numbers of larvae per 5 canes was observed from Aril-May, which coincides with high maximum (36.00- 38.85°C) and minimum temperature (21.85-24.00°C). Correlation studies revealed that maximum (r = 0.732**) and minimum temperature (r = 0.741**) exhibited positive and were highly significant association with mean number of larvae per plant. Multiple regression analysis revealed that increase in 1°C of maximum temperature will lead to increase in mean number of larvae. Regression analysis (R² value) indicates that the influence of temperature was to the extent of 71.40 per cent (Co-86032) and 76.40 per cent (SNK-07680) on the incidence of ESB. There is no significant difference between both varieties. The development and oviposition of ESB seems to be favoured by relative warmer (minimum temperature > 23.8oC and dry nights (RH < 50%). Traceable rainfall was recorded during the investigation which favoured pest population. [ABSTRACT FROM AUTHOR]

Temperature-dependent development rate, percent diapause induction (hibernation at low temperature and aestivation at high temperature), and survival of diapausing larvae of Chilo partellus (Swinhoe, 1885) were examined on 13 constant temperatures ranging from 8 to 40 °C. Development of hibernating and aestivating larvae occurred from 10 to 25 °C and 27–38 °C, respectively. However, no development occurred at 8 °C and 40 °C. To determine actual thermal conditions that affect development and trigger both kind of diapause (hibernation and aestivation), various thermal parameters were estimated by fitting the development rate data to two linear (Ordinary equation and Ikemoto & Takai) models and thirteen non-linear models. The lower thermal thresholds ( T min ) for development of diapausing larvae of C. partellus were calculated as 9.60 °C and 10.29 °C using the ordinary linear model and Ikemoto & Takai model, respectively. Similarly, the thermal constants ( K ) estimated using the ordinary linear model was 333.33 degree-days and that estimated with Ikemoto & Takai model was 338.92 degree-days. Among the non-linear models, Lactin-2 followed by Lactin-1 were found to be the best as these models estimated the critical temperatures ( T min , T max and T opt ) similar to those of observed values. Conclusively, the Ikemoto & Takai linear model and Lactin-2 followed by Lactin-1 non-linear models are useful and efficient for describing temperature-dependent development and estimating the temperature thresholds of diapausing larvae of C. partellus . Our findings provided fundamental information for estimation of thermal requirement and temperature based development models for diapausing larvae of C. partellus . This information will be highly useful for predicting the occurrence, seasonal emergence, number of generations and population dynamics of C. partellus . [ABSTRACT FROM AUTHOR]

Sugarcane early shoot borer, Chilo infuscatellus Snellen is a major menace and cause of considerable damage to sugarcane crops in India. The incidence of early shoot borer has been increasing for the last few years. A new insecticide flubendiamide was evaluated in the field to assess its bioefficacy against sugarcane early shoot borer during February to December 2013 and August 2013 to July 2014. Two rounds of foliar application of flubendiamide 20 WG at 60 and 50 g a.i. ha −1 significantly reduced the early shoot borer in both experiments. Foliar application of flubendiamide 20 WG (50, 100 and 200 g a.i. ha −1 ) in sugarcane did not cause any phytotoxic symptoms. Flubendiamide 20 WG test doses were found to be safe to natural enemies including spiders and coccinellids in the field. Though there was a short term decline in the natural enemy population, it started increasing gradually within a fortnight after treatment. The sugarcane yield increased over the control in the flubendiamide 20 WG (60 g a.i. ha −1 ) treated plots by 32.7 and 31.5% in the two seasons, respectively. The residues of flubendiamide at 50 and 100 g a.i. ha −1 were below detectable levels in sugarcane leaf, juice and soil at harvest. [ABSTRACT FROM AUTHOR]

The present investigation was conducted at research farm of Tirhut College of Agriculture, Dholi, Muzaffarpur (Bihar) during Kharif 2016 to study the population fluctuation of maize stem borer with relation to abiotic factors. Incidence of maize stem borer, Chilo partellus (Swinhoe) started from 2nd week of August and continued upto 4th week of October with peak incidence in 38th standard week. [ABSTRACT FROM AUTHOR]

Previously we have generated a recombinant Chilo iridescent virus (CIV) by inserting the green fluorescent protein gene ( gfp ) into the CIV 157L open reading frame (ORF) locus and showed that this recombinant (rCIV-Δ157L-gfp) was fully infectious both in cell culture as well as in insect larvae. This study opened up a new avenue for increasing the speed of kill of CIV and other iridoviruses by inserting virulence or toxin genes into the viral genome. In the current study we constructed a recombinant CIV (rCIV-Δ157L/gfp-AaIT) where the 157L ORF was replaced with both the AaIT neurotoxin gene from the scorpion Androctonus australis and the gfp gene, each under control of the viral major capsid protein ( mcp ) gene promoter. Recombinant virus was purified by successive rounds of plaque purification using Spodoptera frugiperda (Sf-9) cells. One-step growth curves for the recombinant viruses, rCIV-Δ157L/gfp-AaIT and rCIV-Δ157L-gfp, and wild-type CIVs in Sf-9 cells showed similar profiles. AaIT toxin expression in infected third instar Galleria mellonella larvae was confirmed by western blot analysis using an antibody against the AaIT protein. rCIV-Δ157L/gfp-AaIT infection at a concentration that kills 100% of the larvae caused paralysis in infected third instar G. mellonella larvae from two days after injection, whereas infection with non-AaIT containing viruses showed mortality starting much later (>10 days). Bioassays on these larvae demonstrated that the speed of kill of CIV carrying AaIT was strikingly enhanced as compared to wild-type CIV. These results suggest that insertion of a toxin gene into CIV provides further opportunities to control a wide range of pest insects, such as weevils, using an iridovirus. [ABSTRACT FROM AUTHOR]

Afield experiment was carried out at the Experimental Farm of Sakha Agricultural Station in 2014 rice season using two cultivars, Giza 178 (high tillering capacity) and Egyptian Jasmine (medium tillering capacity) to determine the economic threshold level for control measures of stem borer Chilo agmemnon Bles. in rice. Seven simulated levels of dead hearts; 0, 5, 10, 15, 20, 25 and 30% were adopted to find out their effects on rice yield and yield components. In Giza 178 cultivar, dry matter content was significantly reduced at 25% detillering. Panicle weight, 1000-grain weight and filled grains increased as the detillering level increased. This could be attributed to the compensation phenomenon, as the rice hills that suffered from high detillering produced heavier grains in the remaining tillers. This trend was also obtained with the Egyptian Jasmine. The rice yield was significantly reduced at 15% in the former cultivar and at 20% in the latter one. Economic analysis showed that the economic threshold is 25% damaged tillers in Giza 178 rice cultivar and 20% in the Egyptian Jasmine. This might be due to that Giza 178 is higher tillering cultivar than the Egyptian Jasmine. Thus, control measures, particularly insecticides, should not be applied before dead hearts reach 25% in case of Giza 178 cultivar and 20% in case of Egyptian Jasmine. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Southern Agriculture is the property of Journal of Southern Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Cotesia chilonis (Munakata, 1912) (Hymenoptera: Braconidae, Microgastrinae) is a species used widely for biological control of several species of Chilo (Lepidoptera: Crambidae) stem borers. The genus name, species author and year of publication associated with this parasitoid wasp species have varied historically. Based on the available evidence, a complete account of the history and nomenclatural acts associated with C. chilonis is presented, the different alternatives are weighed and discussed, and what is considered as the best alternative is proposed. It is expected that this paper will contribute to clarity and stability in the use of this species name, author and year. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Latin American & Caribbean Anthropology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Maize, a genetically diverse crop, is the domesticated descendent of its wild ancestor, teosinte. Recently, we have shown that certain maize landraces possess a valuable indirect defense trait not present in commercial hybrids. Plants of these landraces release herbivore-induced plant volatiles (HIPVs) that attract both egg [ Trichogramma bournieri Pintureau & Babault (Hymenoptera: Trichogrammatidae)] and larval [ Cotesia sesamiae Cameron (Hymenoptera: Braconidae)] parasitoids in response to stemborer egg deposition. In this study, we tested whether this trait also exists in the germplasm of wild Zea species. Headspace samples were collected from plants exposed to egg deposition by Chilo partellus Swinhoe (Lepidoptera: Crambidae) moths and unexposed control plants. Four-arm olfactometer bioassays with parasitic wasps, T. bournieri and C. sesamiae, indicated that both egg and larval parasitoids preferred HIPVs from plants with eggs in four of the five teosinte species sampled. Headspace samples from oviposited plants released higher amounts of EAG-active compounds such as ( E)-4,8-dimethyl-1,3,7-nonatriene. In oviposition choice bioassays, plants without eggs were significantly preferred for subsequent oviposition by moths compared to plants with prior oviposition. These results suggest that this induced indirect defence trait is not limited to landraces but occurs in wild Zea species and appears to be an ancestral trait. Hence, these species possess a valuable trait that could be introgressed into domesticated maize lines to provide indirect defense mechanisms against stemborers. [ABSTRACT FROM AUTHOR]

This exploratory study investigates the work of Oliva Sabuco de Nantes Barrera (1562-1626?). Sabuco's major work, New Philosophy of Human Nature neither Known to nor Attained by the Great Ancient Philosophers, which Will Improve Human Life and Health (1587), in many ways foresees the Cartesian system but avoids some of its problems even though or perhaps because her philosophical system rests heavily on the foundations of hylomorphism. The mind/soul is separate from the body, but the two function as a holistic unit. Mind and body affect and are affected by each other within or through the pia mater. This study's aim is to summarize Sabuco's thought and to indicate how her work may be able to address or to lend support to contemporary philosophical concerns. [ABSTRACT FROM AUTHOR]

This study was conducted on both station and farmers' fields during the 2010 dry cropping season in the Vallée du Kou rice scheme. We investigated the effect of three rice-transplanting periods (8–10 days) on the population dynamics, damage and parasitism associated with rice stem borers. The on-station experiment was designed as a randomized complete block with three treatments (planting dates) and four replications. Regular intervals of 14 days were observed between subsequent planting dates. Weekly agronomic and entomological assessments were performed from the 21st day after transplanting (DAT) to the 84th DAT. The on-farm experiment covered 1200 ha divided into two zones in which 48 farmers' fields were selected according to the periods of rice transplanting (resulting in 16 fields per period). On-station results indicated 10.1% of deadhearts and 7.5% of whiteheads due to stem borers in the first transplanting period, resulting in the lowest yield (2 metric tons/ha). In farmers' fields, the genus Chilo was found to be the most injurious rice stem borer in Vallée du Kou. The highest larval parasitism (38.5%) was recorded in the third treatment. These results provide important data that can be used in the development of an integrated management strategy for rice insect pests in Vallée du Kou. [ABSTRACT FROM AUTHOR]

The Asiatic rice borer, Chilo suppressalis (Walker), is an important insect pest of rice in China. The genetic variation of a set of laboratory colonies of C. suppressalis was compared with their source populations in the wild (laboratory colonies BJCK, BJ1AB, and BJ1AC versus wild population BJW; laboratory colonies FZCK and FZ1CA versus wild population FZW) and was analyzed using eight microsatellite markers and two partial mitochondrial DNA (mtDNA) regions (COI and COII). Results from both analyses revealed similar patterns. Microsatellite DNA analysis showed that the two wild populations (BJW and FZW) harbored more private alleles and had higher levels of gene diversity, and observed and expected heterozygosity, compared with the laboratory colonies. Mitochondrial DNA analysis revealed that the two wild populations (BJW and FZW) had higher numbers of haplotypes compared with the five laboratory colonies. The three Beijing laboratory-reared colonies (BJ1CK, BJ1AB, and BJ1AC) had one fixed haplotype (H04). Most of the pairwise FST values based on mtDNA were high and all pairwise FST comparisons based on microsatellite DNA were significant, which indicated that the significant differences between these colonies and populations. Genetic drift caused by several factors, such as founder effect, small effective population size, rearing protocols, and inbreeding, can contribute to the rapid loss of genetic variation and affect the distribution of alleles and haplotypes. Therefore, it is necessary to increase the sample size of source populations to prevent the loss of genetic variation and genetic differentiation between different colonies. [ABSTRACT FROM PUBLISHER]

Maize (Zea mays) is a major staple food in Africa. However, maize production is severely reduced by damage caused by feeding lepidopteran pests. In East and Southern Africa, Chilo partellus is one of the most damaging cereal stem borers mainly found in the warmer lowland areas. In this study, it was hypothesized that the future distribution and abundance of C. partellus may be affected greatly by the current global warming. The temperature-dependent population growth potential of C. partellus was studied on artificial diet under laboratory conditions at six constant temperatures (15, 18, 20, 25, 28, 30, 32 and 35 °C), relative humidity of 75±5% and a photoperiod of L12:L12 h. Several non-linear models were fitted to the data to model development time, mortality and reproduction of the insect species. Cohort updating algorithm and rate summation approach were stochastically used for simulating age and stage structure populations and generate life-table parameters. For spatial analysis of the pest risk, three generic risk indices (index of establishment, generation number and activity index) were visualized in the geographical information system component of the advanced Insect Life Cycle modeling (ILCYM) software. To predict the future distribution of C. partellus we used the climate change scenario A1B obtained from WorldClim and CCAFS databases. The maps were compared with available data on the current distribution of C. partellus in Kenya. The results show that the development times of the different stages decreased with increasing temperatures ranging from 18 to 35 °C; at the extreme temperatures, 15 and 38 °C, no egg could hatch and no larvae completed development. The study concludes that C. partellus may potentially expands its range into higher altitude areas, highland tropics and moist transitional regions, with the highest maize potential where the species has not been recorded yet. This has serious implication in terms of food security since these areas produce approximately 80% of the total maize in East Africa. [ABSTRACT FROM AUTHOR]

Asiatic rice borer, Chilo suppressalis (Walker), larvae cause extensive crop losses worldwide. Because chemical control is problematic, and sex pheromone applications are a valuable management tactic in China, judicious timing of a minimal density of pheromone dispensers is important in developing a cost-effective C. suppressalis IPM program. During June-October in 2011, 20, 30, 40, and 50 dispensers per hectare for mass trapping, and 200, 300, 400, and 500 dispensers per hectare for mating disruption were placed in northeastern China rice fields. Based on those results, only the two highest mass trapping densities were used in 2012-2013. The 40, 50, and 500 dispenser densities reduced egg masses to <2.0 per 100 tillers, compared with >9.5 in the insecticide-treated plots in 2011-2013. The reduced oviposition resulted in >85% reduction of larval damage, which was comparable with the currently used insecticides, dimethoate and deltamethrin (0.35 kg/ha), which gave no egg reduction, but ≈80 and 89% reduction in larval damage. The 40 and 500 densities are recommended to Chinese rice farmers for mass trapping and mating disruption programs, respectively. [ABSTRACT FROM AUTHOR]

A study on susceptibility of promising sugarcane varieties to stalk borer, Chilo auricilius Dudgeon with different levels of nitrogen was conducted at PAU, Regional Research Station Gurdaspur during the year 2010-11 and 2011-12. The pooled mean of both the years showed that sugarcane variety CoJ 89 significantly had less (24.53%) incidence of stalk as compared to other two varieties i.e. CoH 119 (29.28%) and CoJ 85 (35.15%). The incidence of stalk borer increased from 3.70 t0 69.63 percent with increase in nitrogen level from 0 to 90 kg N/ac. The highest cane yield was obtained from the CoH 119 variety at 60 kg N/ac. [ABSTRACT FROM AUTHOR]

In order to investigate further the interest of using the Chilean gene pool in potato breeding programmes, the genetic diversity and population structure of a collection of Solanum tuberosum L. genotypes including 350 worldwide varieties or breeders' lines (referred to as the modern group) and 30 Chiloé Island landraces were examined using simple sequence repeat markers. The close genetic proximity of the Chiloé Island landraces to the modern group was confirmed using several structure analysis methods: principal coordinate analysis; hierarchical clustering analysis; analysis of molecular variance; Bayesian model-based clustering analysis. The latter analysis, in particular, revealed no clear genetic structure between the modern group and the Chiloé Island landraces. The Chiloé Island germplasm appears to represent an interesting gene pool that could be exploited in potato breeding programmes using an association mapping approach. [ABSTRACT FROM AUTHOR]

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