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Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia 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.)

A study of the genetic behaviour in terms of insect resistance, grain quality and anthocyanin character was carried out during the two summer seasons 2016 and 2017. Seven diverse parents viz., Sakha 101, Sakha 104, Sakha 105, Giza 177, Black rice 1, Black rice 2 and Black rice 3 were crossed using a 7 x 7 half-diallel cross analysis without reciprocals to produce 21 F1 crosses during 2016 season. All genotypes were evaluated during 2017 season. The findings showed that general combining ability (GCA) and specific combining ability (SCA) mean squares were significant for all the evaluated characters. The ratio of (δ² GCA /δ² SCA) variances were less than unity, which showed that the inheritance of all traits were controlled by nonadditive gene action. The best general combiner for anthocyanin was Black Rice, while the best general combiners for grain quality were Sakha 105 and Sakha 101. On the other hand, the cross Sakha101 x Sakha 105 recoded the highest significant and negative SCA effects for the insect resistance, while Sakha 105 x Giza 177 was the most promising for grain quality. Furthermore, the dominance (δ²D) genetic variance and the relative importance of SCA percent were higher than the additive genetic variance (δ ²A) and the relative importance of GCA percent for most of the studied characters. These findings revealed that dominance gene action largely governed the studied characteristics. The heritability values in the broad sense ranged from (85.71%) for head rice to (99.7%) for Anthocyanin in brown grain, while the heritability of narrow sense ranged between (7.9 %) for milling percentage to (82.6%) for anthocyanin in milled grains, indicating that the control of these traits were dominated by non-additive effects. [ABSTRACT FROM AUTHOR]

The Bt-cotton RH-647 was developed by Cotton Research Institute CRI, Khanpur has been acknowledged for its possesses superior plant characteristics and potential to yield out under harsh agro-climatic conditions of cotton productive district of Rahimyar Khan in Bahawalpur Division and southern Punjab in 2016. RH- 647 for its novel plant structure and improved fiber quality heat and drought tolerant to withstand successfully sustain yield out in harsh, highly variable hot and dry climatic conditions of and harsh seasoned. RH-647 was developed through one-way hybridization of elite parental genotypes accompanied by pedigree selection method through gene pyramiding technique for incorporation of excellent combinations of fiber traits and CLCuV disease tolerance with higher yield potential right from F1 population. The superior plant combinations were selected in F2-F6 generations were entirely based on phenotypic plant traits and progeny yield potential in field, plant shape, number of bolls per plant, average boll weight (g) and fiber quality traits over standard varieties. The single plant progenies were selected 56 sister lines were tested for Bt-gene (Cry1 Ac) were evaluated for high yielding performance for this superior cross and finally RH-647 as superior breeding line was bulked in year 2010. The strain was evaluated in Randomized Complete Block Design in preliminary yield trials (PYT) and two years in Advance Yield Trials (AYT) trials and Zonal Varietal trials for two years. The superior line 647/10 was ensued for performance in variety attestation tests as RH-647. RH-647 performed best in two years varietal trials (NCVT and PCCT and DUS) conducted for two successive growing seasons (2014–2015 and 2015–2016). RH-647 yielded out significantly compared with standard varieties MNH-886, FH-142 and CIM 602. After completion of mandatory trials in year 2016, RH-647 was approved as new Bt. cotton variety "RH-647". RH-647 is early in maturity with high yield potential and best suited for wheat-cotton cropping pattern. It has fluffy opening and is easy to pick, strongly tolerant to CLCuV disease, high Ginning out turn GOT% (40.2%) with improved fiber traits; staple length (28.3 mm), fiber strength (4.2ug/inch) is duly capable to fulfill all industrial requisitions. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Applied Ecology / Yingyong Shengtai Xuebao is the property of Chinese Journal of Applied Ecology 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.)

Three transgenic soybean lines expressing the Cry1Ia5 gene were developed using the Agrobacterium transformation system. The integration of the Cry1Ia5 gene in the genome of the transgenic plants was approved using specific primers for PCR and real time PCR analysis, respectively. The insecticidal activity of three transgenic lines (L1, L2 and L3) against 2nd larval instars Spodoptera littoralis was tested. The data indicate that L2 exhibited the highest mortality percentage 9 days post feeding (60%) followed by L3 (40%) then L1 (20%) while the control showed 0% mortality. The larvae fed transgenic material appeared smaller in size than compared to the control larvae. The reduction in insect size and weight was due to the accumulation of higher phenoloxidase activity in insect tissues. The higher mortality observed in L2 was due to a significant decrease in the acetylcholine esterase activity that leads to accumulation of acetylcholin at higher levels which causes paralysis and death. The developed transgenic line 2 could be used to construct an insect resistant soybean cultivar. [ABSTRACT FROM AUTHOR]

The maize weevil, Sitophilus zeamais (Motschulsky) (Coleoptera: Curculionidae), is the main pest of stored grains across tropical regions. An alternative strategy to the use of synthetic insecticides for the management of S. zeamais is the development of botanical insecticides based in the essential oils (EOs) from aromatic plants. In the present study, we evaluated the lethal and sublethal effects of the EO of Lippia sidoides (Cham.) and its major compounds (thymol and ρ-cymene) on different populations of S. zeamais . For this, we determined toxicity by fumigation of treatments of five populations from different Brazilian regions and assessed the lethal time and walking behavior for the most tolerant and susceptible populations. The lethal concentration required to kill 50% of S. zeamais populations ranged from 35.48 to 118.29 μL L −1 air for EO of L. sidoides , 65.00–91.23 μL L −1 air for thymol and 801.24 to 2188,83 μL L −1 air for ρ-cymene. Population from Jacarezinho was the most tolerant to treatments, while population of Rio Branco was the most susceptible one. The survival of S. zeamais populations was significantly affected by treatments and ρ-cymene showed the faster action on both Jacarezinho and Rio Branco populations (LT 50  = 0.3 h). The walking behavior of maize weevil showed that the EO of L. sidoides and thymol present repellent effect, however, ρ-cymene present attractive effect. Therefore, the EO of L. sidoides and its major compound thymol are promising source to develop bioinsecticides for the management of S. zeamais populations with different levels of resistance. [ABSTRACT FROM AUTHOR]

This study evaluated toxic effects, repellency and respiration rate caused by terpenoid constituents of cinnamon and clove essential oils and against Sitophilus granarius L. (Coleoptera: Curculionidae). The lethal concentrations (LC 50 and LC 90 ), repellent effect, and behavior repellency response on adults of S. granarius after exposure to six concentrations of each essential oil and terpenoids were evaluated. The chemical composition of the cinnamon oil was also determined and primary compounds were eugenol (10.5%), trans-3-caren-2-ol (10.2%), benzyl benzoate (9.99%), caryophyllene (9.34%), eugenyl acetate (7.71%), α-phellandrene (7.41%), and α-pinene (7.14%). In clove essential oil, the primary compounds were eugenol (27.1%), caryophyllene (24.5%), caryophyllene oxide (18.3%), 2-propenoic acid (12.2%), α-humulene (10.8%), γ-cadinene (5.01%), and humulene oxide (4.84%). Cinnamon and clove essential oil was toxic to S. granarius . In toxic terpenoids compounds, eugenol has stronger contact toxicity in S. granarius than caryophyllene oxide, followed by α-pinene, α-humulene, and α-phellandrene. Insects reduced their respiratory rates after being exposed to essential oil terpenoids and avoided or reduced their mobility on terpenoid-treated surfaces. Cinnamon and clove essential oil, and their terpenoid constituents were toxic and repellent to adult S. granarius and, therefore, have the potential to prevent or retard the development of insecticide resistance. [ABSTRACT FROM AUTHOR]

Acanthoscelides obtectus (Coleoptera: Bruchidae) is one of the most important post-harvest pests of dry bean Phaseolus vulgaris L. Tepary bean ( Phaseolus acutifolius ) could be a novel source of resistance against A. obtectus to improve dry bean. We studied the resistance of tepary bean varieties to A. obtectus . We focused on three categories of defense: antixenosis, antibiosis, and tolerance. Tepary pinto amarillo (T-amarillo) and Tepary pinto negro (T-negro) beans show high antixenosis to adults, increased numbers paralyzed per hour and per day, and increased duration of development in winter; reduced oviposition, number of emerged adults and adult weight. Due to the small number of emerged adults, there was very little grain weight loss. Volatile compounds were discarded as the cause of paralysis in adults. Adults in T-amarillo and T-negro were paralyzed until day 10 and 14 and then, they die at an exponentially increasing rate. In addition T-negro and T-amarillo produced the highest mortality in larvae before entering the seeds. T-amarillo and T-negro showed antixenoxis, resistance and tolerance to A. obtectus infestation and they can be used as sources of resistance for P. vulgaris breeding. The compound that causes the antixenosis and paralysis in adults is in the testa of the resistant varieties and is not likely to be a volatile compound, whereas the mortality and antixenosis in larvae is caused more probably by a volatile compound present in the testa. [ABSTRACT FROM AUTHOR]

Helicoverpa armigera is an important pest infesting a number of crops of high commercial value leading to huge economic losses globally. RNA interference (RNAi) is a potent tool for the control of insect pests and towards this objective, transgenic tomato expressing dsRNA of Juvenile hormone acid methyl transferase (JHAMT) gene of H. armigera was developed. The H. armigera larvae fed on HaJHAMT tomato leaves led to a severe (90%) down regulation of the cognate gene expression thus adversely affected the feeding and metamorphosis. Reduction in larval and pupal weight and inability to undergo complete metamorphosis were observed that led to larval-pupal intermediates and subsequently affected the eclosion. Thus, JH down regulation is an attractive target due to specificity to insects and its important role in insect growth and development to engineer insect resistance in crops using RNAi. [ABSTRACT FROM AUTHOR]

Cotton mealybug Phenacoccus solenopsis Tinsley is an important pest of cotton in Pakistan, and its management is difficult due to the development of insecticide resistance. This research was conducted to characterize the bifenthrin resistance in populations of P. solenopsis and different parameters such as cross-resistance, realized heritability and possible resistance mechanisms were studied to improve the management of this important pest. A field-collected population was selected with bifenthrin in the laboratory for 14 generations and developed a resistance of 178-fold. The realized heritability of bifenthrin resistance was 0.54 in the selected population. The toxicity of bifenthrin was synergized by the addition of either piperonylbutoxide (PBO) or S,S,S tributylphosphorotrithioate (DEF) which suggests a general metabolic resistance due to possible involvement of mono-oxygenases or esterases. However, the resistant population did not develop a significant cross-resistance to either buprofezin, chlorpyrifos or lambda-cyhalothrin. These data suggest that alternative insecticide-based management programs can be developed for this pest in the short-term, but resistance management strategies which can reduce the sole reliance on insecticides are still needed. [ABSTRACT FROM AUTHOR]

The codling moth, Cydia pomonella (L.), is the key pest of apple production worldwide. In Morocco, there is a sustainable presence of codling moth causing considerable damage in apple orchards despite frequent applications of broad spectrum insecticides. For 12 years, sexual trapping and chemical control were performed and the development of the codling moth population was analysed in an orchard which was in the region of Azrou. The efficacy of some insecticides (azinphos-methyl, chlorpyriphos-ethyl, diflubenzuron, thiacloprid, methoxyfenozide, spinosad, and deltamethrin) was also evaluated on neonate larvae and compared with a laboratory sensitive strain. This procedure was done to assess an eventual resistance in Moroccan populations. The action threshold was usually exceeded, leading to an intensive chemical control, with an average frequency of 9 to 13 days. The chemical control was done according to the action persistence time of the insecticides and the trap captures. However, those two parameters are compromised in Moroccan conditions because of the high summer temperatures which disrupt the action of insecticides and exacerbate populations. The pheromone traps may become ineffective and useless. Neonate larvae were resistant to five insecticides out of seven. Such results suggest the presence of a cross resistance in local strains. Overall, the insect resistance, the functioning of the sexual traps, and some insecticides properties (persistence action, pre-harvest interval) are the key factors that could explain the failure to control these moths under Moroccan conditions. [ABSTRACT FROM AUTHOR]

This study aimed to observe the response of 34 rice accessions to attack by sugarcane borer ( Diatraea saccharalis Fabr., 1794) and to analyze the genetic diversity of these accessions by microsatellite markers. Twenty larvae were placed on the leaf sheaths of rice plants. At 30 days after infestation the rice plants at ground level were taken to the laboratory where the signs of borer attack, external and internal diameter of the stem and weight of surviving larvae were determined. For the molecular analysis of rice accessions, 24 microsatellite markers were used. The results of the morphological traits of the rice plant, response of the plant to insect attack, development of the sugarcane borer larvae and molecular data, indicated a genotypic variation. The accessions that most favored larval survival were IAC 47 and Ti Ho Hung. Larvae with highest weight (0.0986 g and 0.0862 g) and the largest internal diameters of the rice stem (3.18 mm) were found in land races “Canela de Ferro” (rust colored stem) and all these “Canela de Ferro” accessions also remained genetically grouped. The most tolerant materials, based on the ability to produce new tillers after larval infestation were, Chiang an Tsao Pai Ku and IR 40 which remained morphological and genetically grouped. The results of this study indicate that all the traits and molecular analyses were able to separate the accessions of rice into different groups in relation to resistance to the sugarcane borer. These materials can be used as donor sources in breeding for genetic resistance to sugarcane borers and can be used as donors to amplify the genetic base of Brazilian rice. [ABSTRACT FROM AUTHOR]

Here, we report multiple molecular forms of Albizia lebbeck trypsin inhibitors (AlTIs) by using a simple and sensitive gel X-ray film contact print technique. About 17 AlTIs were detected in the seed extracts of A. lebbeck. Two groups of AlTIs--1 major (10 AlTIs; slow migration on the gel) and 1 minor (7 AlTIs; fast migration on the gel) were identified. The former was specific only toward trypsin. However, the latter was specific toward both trypsin and Helicoverpa armigera gut proteinases (HaGPs). The most potent AlTI (AlTI13) was purified to assess its in vivo bioefficacy toward HaGPs. Purification was achieved using (NH4)2SO4 fractionation, Sephadex G-100 column chromatography, and preparative native-polyacrylamide gel electrophoresis (PAGE). The dose dependent bioefficacies of AlTIs in the (NH4)2SO4 F3 fractions (0.1%, 0.5%, and 1%) were approximately 79%, 83%, and 90%, respectively, resulting in reductions in the average larval weight of H. armigera. Artificial diet containing a single dose of AlTI13 (5µg/g diet) reduced the larval weight by about 76%, with 60% mortality. The half-maximal inhibitory concentrations (IC50) of AlTI13 for trypsin and HaGPs were 0.14 and 0.17µmol/ml, respectively. The optimum conditions for AlTI13 were pH8 and temperatures ranging from 35 to 40°C. Reducing sodium dodecyl sulfate-PAGE analysis indicated that ~28kDa Kunitz-like trypsin inhibitor was present. Thus, we showed that AlTIs, particularly, AlTI13 of A. lebbeck could be used as a transgene macromolecule to markedly increase insect resistance in genetically engineered plants. [ABSTRACT FROM AUTHOR]

In order to investigate the changes of secondary metabolites content of alfalfa induced by thrips Odontothrips loti damaging, two alfalfa strains, one resistant to thrips (R-1) and the other susceptible to thrips (I-1), were chosen to measure the phenols and lignin contents of alfalfa leaves under infestation with thrips at different densities (0, 1, 3, 5, 7 thrips.branch-1, and 0 thrip.branch-1 as control). After infestation 7 days, the polyphenols, tannin and condensed tannin contents increased in both leaves of R-1 and I-1 with the increasing thrips density, the simple phenols content had no significant difference, while the lignin content increased significantly compared with the control. After infestation 14 days, the polyphenols, tannin, condensed tannin and lignin contents in both leaves of R-1 and I-1 increased obviously with the increasing thrips density, while the simple phenols content had no significant difference. The lignin content increased significantly, and was significantly higher under 7 thrips.branch-1 than under the control. After infestation 21 days, the polyphenols, tannin, and lignin contents in both leaves of R-1 and I-1 increased obviously with the increasing thrips density, and were the highest under 7 thrips.branch-1. Simple phenols content of I-1 strain was increased significantly, but that of R-1 strain had no significant change. The condensed tannin content in both leaves of R-1 and I-1 was not obvious compared with the control. Phenols and lignin contents in R-1 and I-1 leaves increased obviously after thrips infestation, and the polyphenols, tannin and lignin contents increased faster in R-1 strain than in I-1 strain. Thrips infestation had inductive effects on phenols and lignin contents of alfalfa, which could be used to evaluate the resistance of alfalfa. [ABSTRACT FROM AUTHOR]

Abstract: Eggplant shoot and fruit borer (ESFB), Leucinodes orbonalis Guenée, is a major insect pest of eggplant, Solanum melongena L. In this study, cry1Aa3 gene was introduced into eggplant cv. Kashi Taru through Agrobacterium-tumefaciens mediated transformation. Hypocotyl explants from 7 day-old seedlings were pre-cultured for two days and inoculated with Agrobacterium strain EHA105 harboring a synthetic cry1Aa3 gene with full codon-modification in a binary vector. PCR and Southern blot analyses confirmed the presence of single copy insertions of the cry1Aa3 gene in plants of four independent transformation events. In addition, single copy gene insertions were confirmed by segregation analysis of T1 seedlings. Expression of the cry1Aa3 transcripts was confirmed by qRT-PCR; and ELISA revealed presence of Cry1Aa3 protein in fresh leaves (30.9–44.3 ng g−1) and fruits (20.5–35.7 ng g−1). Expression of the Cry1Aa3 protein resulted in high ESFB larval mortality in the shoot as well as fruit tissues of the transformed eggplant lines. Such transgenic eggplant lines possessing resistance to the ESFB could reduce dependency on pesticide use for ESFB control, leading to a safer environment and eggplant fruits. [Copyright &y& Elsevier]

Abstract: The plasmid of pCDMARUBA-Hyg, which contained two insect-resistance genes, sbk (modified from Cry1A(c)) and sck (modified from CpTI), was transformed into an Agrobacterium EHA105 for infection of the calli of a super japonica rice Nanjing 45. Primarily, using polymerase chain reaction (PCR) detection with the primers of sbk and sck genes, 42 positive transgenic plants that were marker-free and contained the two target genes were selected from 97 regenerated plants. Results of southern-blotting indicated that 23, 11, 5, 2 and 1 plants had one, two, three, four and five copies of the transformed genes, respectively. Analysis of reverse transcription PCR (RT-PCR) and Bt gene testing paper showed that 28 T3 generation plants derived from four transgenic plants having a single copy were insect-resistant. Feeding experiment with rice stem borer revealed that the insect resistance was greatly increased with the larva mortality ranging from 94% to 100%. In addition, among the transgenic plants, three T3 transgenic plants possessed some desirable characteristics for breeding and production, such as plant height, seed-setting rate, 1000-grain weight and larva mortality. The mechanism of insect resistance of Bt gene and its application in rice transgenic research were also briefly discussed. [Copyright &y& Elsevier]

Abstract: Bt5198, a new rice restorer line containing Bt gene, was developed from the cross and backcross of the elite restorer line Chenghui 177 with Bt Minghui 63, a transgenic Bt restorer line. The inbred lines were evaluated using PCR amplification, test paper evaluation, insect resistance evaluation in both the laboratory and paddy fields, nursery evaluation of rice blast resistance and pedigree selection of agronomic traits. Larval mortalities on Bt5198 and Bt Minghui 63 were 100% when rice culms were inoculated with the eggs of the striped stem borer (SSB) in the laboratory. Bt5198 was highly resistant against SSB and the yellow stem borer (YSB) under field conditions. The F1 hybrids derived from Bt5198 and four cytoplasmic male sterile (CMS) lines were also highly resistant to SSB and YSB and had a significant heterosis. Two-year evaluation of rice blast resistance confirmed that the resistance levels of Bt5198 to leaf blast and neck blast were similar to those of Chenghui 177 and significantly better than those of Bt Minghui 63. Seed germination ability and pollen yield of Bt5198 were similar with Chenghui 177, suggesting that the introduction of the Bt gene into the new restorer line had no significant effects on seed vitality or the yield of seed production. To identify the presence of the Bt gene, it was effective to combine test paper examination with the evaluation of insect-resistance, both in the laboratory and under field conditions. [Copyright &y& Elsevier]

Transgenic crops have been grown commercially for about 12 years, with a continuos increase of the cultivated area, and now represent a substantial fraction of the total world production for the major GM crops: soybean, maize, rapeseed and cotton. The "first generation" of genetically modified crops, those which are now growing in the fields, were designed for the improvement of agronomic characteristics, mostly herbicide tolerance and insect resistance. The "second generation" of transgenics focused on quality improvement, for example of nutritional value, but has not yet lived up to expectations. Now, the "third generation" of engineered plants is about to enter the market, designed to be used as biofactories for the production of a wide variety of high value, pharmacological and industrial compounds. This novel "molecular farming" offers enormous possibilities, but will require stringent regulations and control mechanisms to avoid new, potentially serious risks human health, though possible contamination of the food supply. [ABSTRACT FROM AUTHOR]

Abstract: In Hawaii, infestations of yellow sugarcane aphid (YSA), Sipha flava (Forbes) (Homoptera: Aphididae) reduced growth of the forage grass, kikuyu (Pennisetum clandestinum Hochst. ex Chiov). To determine the effects of nitrogen (N) and potassium (K) on tolerance of kikuyu grass to YSA, cuttings of eight and five cultivars were grown in the greenhouse using nutrient solutions in two separate trials, respectively. The first trial was conducted during the summer of 1991 and the second during the winter of 1993. In both trials, kikuyu was grown at three N levels (0.05, 0.5 and 3.0mM) and four K levels (0.05, 0.5 1.0 and 3.0mM), with one cultivar comprising a block. Prior to exposure to aphids, representative plants were harvested, and shoots were analyzed for foliar nutrients. Then, plants were confined with aphids and rated visually for YSA injury. Dry matter yields and foliar N concentration increased significantly with increasing N fertilization in both trials. In the first trial, there was a significant interaction between N and K levels, in which the greatest increases of shoot and root dry matter with increasing N levels were found at the highest K level. In the second trial, K fertilization had no effect on dry weight of shoots. In both trials, foliar K concentration increased significantly with increasing K levels. Damage due to YSA tended to increase with increasing N levels, although it was unaffected by K fertilization in both trials. Thus, fertilization with increasing N resulted in greater kikuyu dry matter production, but it also tended to increase the damage caused by YSA feeding. [Copyright &y& Elsevier]

Abstract: Kikuyu grass, Pennisetum clandestinum Hochst. ex Chiov., is an important pasture species in many subtropical areas. Infestations of yellow sugarcane aphid (YSA), Sipha flava (Forbes) (Homoptera: Aphididae), have reduced kikuyu forage production in Hawaii. A novel method was developed to screen cultivars of kikuyu, and species of other forage and turf grasses for resistance to YSA. Kikuyu germplasm differed significantly in response to YSA with certain kikuyu hybrids more resistant to YSA than the common cultivar. However, even the kikuyu cultivars with the lowest damage ratings were considered only to be moderately resistant to YSA. Other forage grass species differed significantly in YSA damage, with Pacific fountain [Pennisetum macrostachys (Brongn.) Trin.], dallis (Paspalum dilatatum Poir.), torpedo (Panicum repens L.), tall fescue (Festuca arundinacea Schreb.), signal [Urochloa brizantha (Hochst. ex A. Rich.) R.D. Webster, formerly known as Brachiaria decumbens], bahia (Paspalum notatum Flugge), small buffalo (Panicum coloratum L.), velvet (Holcus lanatus L.), and switch (Panicum virgatum L.) grasses considered to be resistant to YSA. Turf grass species also differed significantly in YSA injury, with seashore paspalum (Paspalum vaginatum Sw.), St. Augustine [Stenotaphrum secundatum (Walter) Kuntze], and Japanese lawn (Zoysia japonica Steud.) grasses evaluated as resistant. Reduction of pasture forage by YSA could be ameliorated either by utilization of moderately tolerant kikuyu hybrids or resistant forage grass species. [Copyright &y& Elsevier]

Abstract: The insect growth regulator (IGR) hydroprene is a juvenile hormone analogue used in urban and stored-product insect control programs in the United States and in other developed countries. Hydroprene can be considered as an alternative to conventional insecticides because of its specific activity against immature insect stages, low persistence in the environment, and virtually non-toxic effects on mammals. Several published records demonstrate the excellent potential of hydroprene to control many stored-product insects. However, there are concerns of insect resistance to all insecticides, including IGRs. We review the mode of action of hydroprene in insects, examine how hydroprene is used in agricultural and urban pest management systems, describe research with hydroprene in stored-product pest management, and discuss potential mechanisms by which insects could develop resistance to this chemical. We also identify potential areas of further research with hydroprene that include, but are not limited to, the estimation of effects of hydroprene on different flooring surfaces, evaluation of multiple methods of hydroprene application in a facility, identification of other control methods to be used in combination with hydroprene, identification of specific life stages of stored-product insects that are especially vulnerable to hydroprene, and inclusion of the effects of hydroprene in stored-product insect population models. [Copyright &y& Elsevier]

Abstract: We report the first field trials of indica basmati rice expressing two Bt genes, cry1Ac and cry2A simultaneously. Different transgenic lines were sown under field conditions for two consecutive years (2001 and 2002). Artificial infestation of yellow stem borer (YSB, Scirpophaga incertulas) and natural infestation of rice leaf folder (RLF, Cnaphalochrocus medinalis) were studied. Transgenic lines showed up to 100% and 98% resistance against YSB at vegetative and flowering stages, respectively, with 98% additional resistant against RLF as compared with the control. Variation in some morphological characteristics, e.g., the average number of tillers, plant height and maturity, were also observed. Transgenic lines produced up to 59% more grains than control plants under artificially augmented conditions, while up to an 8% increase was recorded under natural infestations. All lines expressed high level of Cry proteins when compared with commercially released cultivars of Bt cotton, maize and potato. It was also observed that although toxin titer substantially decreased with increasing age of the plants, it remained well within the limits necessary to kill the target insects. It was also observed that the transgenic lines released Bt toxins from roots into Murashige and Skoog basal medium, hydroponic cultures and soil, which could be detected through sandwich ELISA. On the basis of these results these lines seem good candidates to be released as the first commercial cultivars of Bt indica basmati rice. [Copyright &y& Elsevier]

Abstract: Collards (Brassica oleracea var. acephala) are an important vegetable crucifer produced worldwide for human consumption, and one subject to severe injury by Lepidoptera. We have produced Bacillus thuringiensis (Bt)-transgenic collard lines that have the potential to be used either for direct control or as a “dead end” trap crop for Lepidoptera. To produce collard lines expressing Bt genes, a cry1Ac Bt gene, in association with the nptII gene for kanamycin-resistance, and a cry1C Bt gene, in association with the hpt gene for hygromycin-resistance, were introduced into seedling explants by Agrobacterium tumefaciens-mediated transformation. A total of 30 kanamycin-resistant and 28 hygromycin-resistant plants were regenerated from two collard cultivars (“McCormack''s Green Glaze” [glossy leaves] and “Champion” [non-glossy leaves]). PCR assays of the kanamycin- and hygromycin-resistant plants and Southern analyses of the hygromycin-resistant Champion plants confirmed the presence and integration of the associated Bt genes. ELISA analyses of leaf tissue from the antibiotic-resistant plants showed that production of the Cry1Ac and Cry1C Bt proteins varied greatly among independent transformants, ranging from undetectable to over 2000ng of Bt protein/mg of total soluble protein. All cry1Ac and cry1C collard plants in which Bt protein was detected caused complete mortality of larvae from susceptible diamondback moth, Plutella xylostella. Cry1Ac-transgenic plants also controlled P. xylostella populations resistant to Cry1C protein, while cry1C-transgenic plants controlled Cry1Ac-resistant P. xylostella. Sexual crosses have produced lines with both Bt genes. “McCormack''s Green Glaze” plants were more attractive for P. xylostella oviposition than cabbage plants and hence are suitable for use as “dead end” trap crops. If approved for human consumption in the future, Bt collards could serve not only as a trap crop but also as a cash crop, thereby expanding the traditional role of a trap crop. This example of Bt collards illustrates the potential for using biotechnology in multiple ways for insect control. [Copyright &y& Elsevier]

Chickpea, Cicer arietinum, is the third most important grain legume crop in the world, with India being the largest producer. Insect pests are a major constraint to chickpea production. In India, the legume pod borer Helicoverpa armigera is the major insect pest of chickpeas. However, sap-sucking insects that act as vectors for viral diseases and bruchid beetles in storage are also considered important pests. Here we give an overview over the different management options to control these pests. There is a growing interest in the genetic modification of crops to enhance their resistance against insect pests. Here we present the state-of-the-art of chickpea transformation and give an overview on the available insecticidal genes that could be deployed to increase insect resistance in chickpea. Prior to commercialization, transgenic crops have to be assessed for their effects on the environment including the possible impact on non-target arthropods, many of which are important for biological pest control. Therefore, the arthropod–food web in the Indian chickpea system is described. Possible routes through which entomophagous insects could be exposed to insecticidal proteins expressed by genetically modified chickpeas are discussed, and species that could be selected for pre-release risk assessment are recommended. [Copyright &y& Elsevier]

Transgenic rice lines containing the snowdrop (Galanthus nivalis) lectin gene (GNA) were investigated for the stability of expression of the GNA gene in the sixth (R6) generation. Western blot analysis revealed that GNA was stably expressed among the R6 individual plants at comparable levels with those from their parental lines. Insect bioassay tests of two independent transgenic rice homozygous R6 lines (Nos. 1 and 2) showed that both lines caused significant inhibition to the rice small brown planthopper (Laodelphax striatellus, SBPH) by decreasing SBPH survival, overall fecundity and retarding its development. These SBPH-resistant lines have been incorporated into a rice insect resistance breeding program for the control of SBPH. This is the first report that transgenic rice lines expressing GNA conferred enhanced resistance to SBPH. [Copyright &y& Elsevier]

Over 25 000 transgenic field trials were conducted globally from 1986-1997, and many transgenic crops, including soybean (Glycine max), maize (Zea mays), tobacco (Nicotiana tabaccum), cotton (Gossypium hirsutum), canola (Brassica napus, B. rapa), tomato (Lycopersicon esculentum) and potato (Solanum tuberosum) have been commercially released. There has been a high adoption rate, with at least 28 million ha reported for 1998, with herbicide- and insect-resistant plants occupying 71 and 28% of the releases, respectively. The current status ofcommercial production of transgenic crops in Canada is summarized. Transgenic crops have the potential to change weed communities/populations in three principal ways, via: 1) escape and proliferation of thetransgenic plants as 'weedy' volunteers with subsequent displacementof the crop, weed and/or natural vegetation; 2) hybridization with and transgene infiltration into related weedy and/or wild species, resulting in invigorated weeds and/or alteration of natural gene frequencies in these species; and 3) genetic changes in populations of unrelated species, as a result of changes to the environment, in particular herbicide-resistant (HR) transgenic crops and the development of HRweeds. Potential risk can be estimated a priori using knowledge of the systematics of crop/wild/weed complexes. Risk must be assessed on a case-by-case basis for each crop each country/ecological region, and for each trait. Potential weed risks will be greater if crop volunteers are predisposed to becoming weedy, are well adapted to the Canadian climate and if sexually compatible wild species are present. [ABSTRACT FROM AUTHOR]

No abstract. [ABSTRACT FROM AUTHOR]