Search Results for: Cotton

Abstract: Effects of pesticide applications, based on an IPM program on cotton bollworm, Helicoverpa armigera Hübner, cotton mirids and cotton leafhoppers, were evaluated in transgenic Bt-cotton and non-transgenic cotton agroecosystems between 1999 and 2001 in China. Differences in pest populations between cotton varieties were also compared. In 1999 and 2000, bollworm populations on non-transgenic cotton …

Abstract: The present paper reports case study results of the risk assessment of transgenic Bt cotton on a non-target pest, cotton aphid, Aphis gossypii. Several types of techniques, i.e., electrical penetration graph (EPG), light and electron microscopy, bioassays and chemical analysis, were applied to investigate physical and chemical leaf factors of 2 transgenic Bt cotton …

Abstract: With the wide adoption of transgenic Bacillus thuringiensis (Bt) cotton, the incidence of bollworm has reduced significantly, but secondary pests such as cotton spider mites have become serious problems in Bt cotton fields. The objective of the present study was to investigate the underlying mechanism of increased incidence of secondary pests in Bt cotton. …

Abstract: Background. Cotton with coevolving pests has been grown in India more than 5000 years. Hybrid cotton was introduced in the 1970s with increases in fertilizer and in insecticide use against pink bollworm that caused outbreaks of bollworm. Hybrid Bt cotton, introduced in 2002 to control bollworm and other lepidopteran pests, is grown on more …

Abstract: The density of Helicoverpa armigera (Hübner) populations on Bacillus thuringiensis Berliner (Bt) transgenic cotton, corn, peanut, and soybean; differences in its development on Bt cotton and common (nontransgenic) cotton; and the potential for mating among populations from Bt cotton fields and other crop fields were investigated in the suburbs of Xinxiang City (Henan Province) …

Abstract: The introduction of transgenic insect-resistant cotton into agricultural ecosystems has raised concerns regarding its ecological effects. Many studies have been conducted to compare the differences in characteristics between transgenic cotton and conventional counterparts. However, few studies have focused on the different responses of transgenic cotton to stress conditions, especially to the challenges of pathogens. …

Abstract: The quantitative levels of CrylAc and the seasonal de cline in expression differed significantly among the eight commercial Bollgard hybrids tested. The CrylAc ex pression was found to be variable among the hybrids and also between different plant parts. The leaves of ßt-cotton plants were found to have the highest levels of CrylAc expression …

Abstract: Bt-cotton seed has been effective to control the damage of bollworm in Chinese cotton production since 1999, reducing the need for pesticides and increasing incomes of Chinese farmers. Field data collected in 2004 indicates that these benefits have been eroded by increasing the use of pesticides aimed to control secondary pests. The combination of …

Abstract: Transgenic cotton expressing Bt (Bacillus thuringiensis) toxins is currently cultivated on a large commercial scale in many countries, but observations have shown that it behaves variably in toxin efficacy against target insects under field conditions. Understanding of the temporal and spatial variation in efficacy and the resulting mechanisms is essential for cotton protection and …

Abstract: This note examines costs and returns from the cultivation of different types of cotton in a rainfed village in the Vidarbha region of Maharashtra, India. While the pros and cons of GM cotton are extensively debated, there are only a few empirical studies on the economic performance of Bt cotton, particularly under rainfed conditions. …

Abstract: The components of the root exudates from two transgenic insect-resistant cotton lines and their parental cotton lines, and their effects on the growth of Fusarium oxysporum were investigated. The results demonstrated that the resistance of transgenic insect-resistant cotton to F. oxysporum was significantly reduced compared with their parental lines. Likewise, the root exudates from …

Abstract: Bt cotton are plants that have been genetically modified to express the insecticidal proteins Cry 1 Ac from subspecies of the bacterium, Bacillus thuringiensis israelensis (Bt), to control bollworm pest that feed on cotton. There is a persistent environmental concern that transgenic Bt-crops carry genes that have indirect undesirable effect to natural and agro– …

Abstract: Transgenic Bt-cotton is commercially cultivated on the rationale that it produces toxins that defend the plants primarily from caterpillars damaging cotton bolls. From the context of crop protection, it is important that these bollworms remain susceptible to the toxins, so that their populations are under check. However, if certain individuals are able to survive …

Abstract: Evolution of pest resistance reduces the efficacy of insecticidal proteins from Bacillus thuringiensis (Bt) used in sprays or in transgenic crops. Although several pests have evolved resistance to Bt crops in the field, information about the genetic basis of field-evolved resistance to Bt crops has been limited. In particular, laboratory-selected resistance to Bt toxin …

Abstract: One Bacillus thuringiensis variety aizawai and several B. thuringiensis variety kurstaki insecticides were evaluated using dosage-mortality bioassays to determine toxicity against a reference soybean looper, Pseudoplusia includens (Walker), strain. Costar and Design WSP (B. thuringensis variety aizawai) had the lowest LC50s followed by Dipel ES, Condor XL, and Javelin WG. LC50s were highest for …

Abstract: Respected Sir, Kindly find herewith a review of Bt-cotton benefits and concerns in India. The manuscript contains details of the experiences with the technology in India, and can be extended into a complete book. However I would like to highlight the following points and concerns for your kind consideration: There is a need for …

Abstract: China was the first developing country to introduce Bt cotton on a large scale. This paper provides an indepth economic analysis of Bt cotton production by small-scale farmers in China. Data were collected in 2002 in Linqing County, in Shandong Province and comprised a season-long cotton production monitoring with 150 farmers and complementary household …

Abstract: Herbicide spray drift is a major concern in the application of agricultural herbicides. In Mississippi, many corn, soybean, and cotton fields are located in close proximity,thus herbicides used in one crop may contact non-target crops by drift. The use of transgenic crops in agriculture has increased dramatically over the past few years. Transgenic crops …

Abstract: In the past, scientific research has predicted a decrease in the effectiveness of Bt cotton due to the rise of secondary and other sucking pests. It is suspected that once the primary pest is brought under control, secondary pests have a chance to emerge due to the lower pesticide applications in Bt cotton cultivars. …

Abstract: Background. Characterizing the spatial patterns of gene flow from transgenic crops is challenging, making it difficult to design containment strategies for markets that regulate the adventitious presence of transgenes. Insecticidal Bacillus thuringiensis (Bt) cotton is planted on millions of hectares annually and is a potential source of transgene flow. Methodology/Principal Findings. Here we monitored …

Abstract: Transgenic Cry1Ac + CpTI cotton (CCRI41) is increasingly planted throughout China. However, negative effects of this cultivar on the honey bee Apis mellifera L., the most important pollinator for cultivated ecosystem, remained poorly investigated. The objective of our study was to evaluate the potential side effects of transgenic Cry1Ac + CpTI pollen from cotton …

Abstract: A silty loam soil was incubated with the leaves and stems of two transgenic Bacillus thuringiensis (Bt) cotton varieties and nontransgenic Bt cotton to study the soil persistence of the Bt toxin from the decomposing transgenic Bt cotton tissues and its effect on soil enzyme activities. The results showed that after Bt cotton tissue …

Abstract: The attenuation of disease resistance in transgenic insect-resistant cotton has become one of the important factors restricting cotton production in China. Two transgenic insect-resistant cotton lines and their parental conventional cotton lines were used as the testing materials. The effects of root exudates of these cotton lines on the spore germination and mycelial growth …

Abstract: Studies were conducted at three locations in North Carolina in 2004 to evaluate density-dependent effects of glyphosate-resistant (GR) corn on GR cotton growth and lint yield. GR corn was taller than GR cotton as early as 25 d after planting, depending on location. A GR corn density of 5.25 plant/m of crop row reduced …

Abstract: Agriculture Times of yore in AgBioForum, current science and many agriculture journal issues have been discussed Bt cotton safety (Manjunath 2011) controversies (Geeta Bharathan 2001), success (Camille Gonsalves 2007), resistance issues (Akshaya et al., 2010) and cost-benefit analysis (Manjunath 2011) in India a question rose as to “Bt or Non-Bt”. Therefore, a typical collective …