Overexpression of GhGSTF9 Enhances Salt Stress Tolerance in Transgenic Arabidopsis.

Soil salinization is a major abiotic stress factor that negatively impacts plant growth, development, and crop yield, severely limiting agricultural production and economic development. Cotton, a key cash crop, is commonly cultivated as a pioneer crop in regions with saline-alkali soil due to its relatively strong tolerance to salt. This characteristic renders it a valuable subject for investigating the molecular mechanisms underlying plant salt tolerance and for identifying genes that confer salt tolerance. In this study, focus was placed on examining a salt-tolerant variety, E991, and a salt-sensitive variety, ZM24. A combined analysis of transcriptomic data from these cotton varieties led to the identification of potential salt stress-responsive genes within the glutathione S-transferase (GST) family. These versatile enzyme proteins, prevalent in animals, plants, and microorganisms, were demonstrated to be involved in various abiotic stress responses. Our findings indicate that suppressing GhGSTF9 in cotton led to a notably salt-sensitive phenotype, whereas heterologous overexpression in Arabidopsis plants decreases the accumulation of reactive oxygen species under salt stress, thereby enhancing salt stress tolerance. This suggests that GhGSTF9 serves as a positive regulator in cotton's response to salt stress. These results offer new target genes for developing salt-tolerant cotton varieties.

Transcriptome diversity assessment of Gossypium arboreum (FDH228) leaves under control, drought and whitefly infestation using PacBio long reads.

Alternative splicing (AS) and alternative polyadenylation (APA) are common mechanisms in eukaryotes to increase the complexity of transcriptomes and subsequently proteomes. Analysis of long reads transcriptomics data can result in the discovery of novel transcripts, splice sites, AS or APA events. Gossypium arboreum is an important cultivated cotton species and a putative contributor of the A sub-genome to the modern tetraploid cotton; and inherently tolerant to several biotic and abiotic stresses. Specifically, its variety 'FDH228' is considered to be an important resistance source. In this study, we sequenced the G. arboreum (var. FDH228) transcriptome using PacBio IsoSeq and illumina short read sequencing under three different conditions i.e. untreated/healthy, treated with biotic stress through whitefly infestation, and treated with abiotic stress via water deprivation, for the discovery and surveying of canonical and non-canonical AS, APA and transcript fusion events. We were able to obtain 15,419 unique transcripts from all samples representing 11,343 genes, out of which 10,832 were annotated and 520 were novel with respect to the published reference genome. These transcripts were grouped into different structural categories including 60 Antisense, 11,959 having a full-splice match, 999 with incomplete-splice match, 30 fusion transcripts, 177 genic, 479 intergenic, 771 novels in the catalog, and 944 Novel but not found in the catalog. Subsequently, randomly selected candidate transcripts were experimentally validated using qRT-PCR. Our comprehensive identification of canonical and non-canonical splicing events, and novel and fusion transcripts aids in the understanding of the resistance mechanisms for this specific germplasm.

Secondary metabolite pathway of SDG (secoisolariciresinol) was observed to trigger ROS scavenging system in response to Ca2+ stress in cotton.

Ca2+ is an essential nutrient for plants and animals which plays an important role in plant signal transduction. Although the function and regulation of mechanism of Ca2+ in alleviating various biotic and abiotic stresses in plants have been studied deeply, the molecular mechanism to adapt high Ca2+ stress is still unclear in cotton. In this study, 103 cotton accessions were germinated under 200 mM CaCl2 stress, and two extremely Ca2+-resistant (Zhong 9807, R) and Ca2+-sensitive (CRI 50, S) genotypes were selected from 103 cotton accessions. The two accessions were then germinated for 5 days in 0 mM CaCl2 and 200 mM CaCl2 respectively, after which they were sampled for transcriptome sequencing. Morphological and physiological analyses suggested that PLR2 specifically expressed in R may enhance the ability of cotton to scavenge ROS by promoting the synthesis of SDG. In conclusion, this study proposed the adaptation mechanisms to response to the high Ca2+ stress in cotton which can contribute to improve the stress resistance of cotton.

Engineered resistance and risk assessment associated with insecticidal and weeds resistant transgenic cotton using wister rat model.

Stacking multiple genes into cotton crop to cop up multiple biotic stresses such as insects and weeds is a promising tool to save crop from losses. Transgenic cotton variety, VH-289, with double Bt and cp4EPSPS genes under the control of 35S promoter was used for the expression analyses and biosafety studies. The transgenic cotton plants were screened through PCR amplification of fragments, 1.7 kb for Cry1Ac, 582 bp for Cry2A and 250 bp for cp4EPSPS; which confirmed the presence of all genes transformed in transgenic cotton. The Cry1Ac + Cry2A and cp4EPSPS proteins were quantified through ELISA in transgenic cotton plants. The Glyphosate assay performed by spraying 1900 mL per acre of glyphosate Roundup further confirmed complete survival of transgenic cotton plants as compared to the non-transgenic cotton plants and all weeds. Similarly, insect infestation data determined that almost 99% insect mortality was observed in controlled field grown transgenic cotton plants as compared to the non-transgenic control plants. Evaluation of effect of temperature and soil nutrients availability on transgene expression in cotton plants was done at two different cotton growing regions, Multan and Lahore, Pakistan and results suggested that despite of higher temperature in Multan field, an increased level of Cry and cp4EPSPS proteins was recorded due to higher soil organic matter availability compared to Lahore field. Before commercialization of any transgenic variety its biosafety study is mandatory so, a 90 days biosafety study of the transgenic cotton plants with 40% transgenic cottonseeds in standard diet showed no harmful effect on wister rat model when studied for liver function, renal function and serum electrolyte.

Assessment of heterosis based on parental genetic distance estimated with SSR and SNP markers in upland cotton (Gossypium hirsutum L.).

BACKGROUND: Heterosis has been extensively utilized in different crops and made a significant contribution to global food security. Genetic distance (GD) is one of the valuable criteria for selecting parents in hybrid breeding. The objectives of this study were to estimate the GD between parents using both simple sequence repeat (SSR) markers and single nucleotide polymorphism (SNP) markers and to investigate the efficiency of the prediction of hybrid performance based on GD. The experiment comprised of four male parents, 282 female parents and 1128 F1, derived from NCII mating scheme. The hybrids, their parents and two check cultivars were evaluated for two years. Performance of F1, mid-parent heterosis (MPH), and best parent heterosis (BPH) were evaluated for ten agronomic and fiber quality traits, including plant height, boll weight, boll number, lint percentage, fiber length, fiber strength, fiber uniformity, fiber elongation ratio, micronaire, and spinning consistent index. RESULTS: Heterosis was observed in all hybrids and, the traits like plant height, boll number, boll weight and lint percentage exhibited higher heterosis than the fiber quality traits. Correlations were significant between parental and F1 performances. The F1 performances between three hybrid sets (Elite×Elite, Exotic×Elite, and Historic×Elite) showed significant differences in eight traits, including boll number, lint percentage, fiber length, fiber strength, fiber uniformity, fiber elongation ratio, micronaire, and spinning consistent index. The correlation of the GD assessed by both SSR and SNP markers was significantly positive. The cluster analysis based on GD results estimated using SNP showed that all the female parents divided into five groups and the F1 performance between these five groups showed significant differences in four traits, including lint percentage, micronaire, fiber strength, and fiber elongation ratio. The correlation between GD and F1 performance, MPH and BPH were significant for lint percentage and micronaire. CONCLUSIONS: Our results suggested that GD between parents could be helpful in heterosis prediction for certain traits. This study reveals that molecular marker analysis can serve as a basis for assigning germplasm into heterotic groups and to provide guidelines for parental selection in hybrid cotton breeding.

Transgenic cotton and sterile insect releases synergize eradication of pink bollworm a century after it invaded the United States.

Invasive organisms pose a global threat and are exceptionally difficult to eradicate after they become abundant in their new habitats. We report a successful multitactic strategy for combating the pink bollworm (Pectinophora gossypiella), one of the world's most invasive pests. A coordinated program in the southwestern United States and northern Mexico included releases of billions of sterile pink bollworm moths from airplanes and planting of cotton engineered to produce insecticidal proteins from the bacterium Bacillus thuringiensis (Bt). An analysis of computer simulations and 21 y of field data from Arizona demonstrate that the transgenic Bt cotton and sterile insect releases interacted synergistically to reduce the pest's population size. In Arizona, the program started in 2006 and decreased the pest's estimated statewide population size from over 2 billion in 2005 to zero in 2013. Complementary regional efforts eradicated this pest throughout the cotton-growing areas of the continental United States and northern Mexico a century after it had invaded both countries. The removal of this pest saved farmers in the United States $192 million from 2014 to 2019. It also eliminated the environmental and safety hazards associated with insecticide sprays that had previously targeted the pink bollworm and facilitated an 82% reduction in insecticides used against all cotton pests in Arizona. The economic and social benefits achieved demonstrate the advantages of using agricultural biotechnology in concert with classical pest control tactics.

Transgenic Cry1Ac/CpTI cotton assessment finds no detrimental effects on the insect predator Chrysoperla sinica.

The widespread commercialization of genetically modified (GM) cotton makes it important to assess the potential impact of this recombinant crop on non-target organisms. As important natural enemies of cotton field predators, green lacewing Chrysoperla sinica larvae are exposed to Bt insecticidal proteins expressed by GM cotton by feeding on herbivorous pests, and adults are directly exposed to Bt proteins by cotton pollen consumption. However, potential impacts of transgenic Bt cotton on C. sinica remain unclear. In this study, we evaluated the effects of two transgenic cotton varieties, CCRI41 and CCRI45, which express Cry1Ac (Bt toxin) and CpTI (Cowpea Trypsin Inhibitor), on C. sinica larvae and adults. After being fed with cotton aphids Aphis gossypii reared on transgenic cotton, the survival rate, developmental duration, pupation rate, and emergence rate of larvae were not adversely affected. After being fed two types of transgenic cotton pollen, the 7-day weight of adults and the preoviposition period and the cumulative oviposition of females were not significantly different from control specimen. Taken together, these results indicate that the potential risks of the two tested GM cotton varieties for the predator C. sinica are negligible. CAPSULE: Our study indicated that GM cotton varieties CCRI41 and CCRI45 have no adverse effects on insect predator C. sinica.

Construction of Gossypium barbadense Mutant Library Provides Genetic Resources for Cotton Germplasm Improvement.

Allotetraploid cotton (Gossypium hirsutum and Gossypium barbadense) are cultivated worldwide for its white fiber. For centuries, conventional breeding approaches increase cotton yield at the cost of extensive erosion of natural genetic variability. Sea Island cotton (G. barbadense) is known for its superior fiber quality, but show poor adaptability as compared to Upland cotton. Here, in this study, we use ethylmethanesulfonate (EMS) as a mutagenic agent to induce genome-wide point mutations to improve the current germplasm resources of Sea Island cotton and develop diverse breeding lines with improved adaptability and excellent economic traits. We determined the optimal EMS experimental procedure suitable for construction of cotton mutant library. At M6 generation, mutant library comprised of lines with distinguished phenotypes of the plant architecture, leaf, flower, boll, and fiber. Genome-wide analysis of SNP distribution and density in yellow leaf mutant reflected the better quality of mutant library. Reduced photosynthetic efficiency and transmission electron microscopy of yellow leaf mutants revealed the effect of induced mutations at physiological and cellular level. Our mutant collection will serve as the valuable resource for basic research on cotton functional genomics, as well as cotton breeding.

Comparing agronomic and phenotypic plant characteristics between single and stacked events in soybean, maize, and cotton.

Genetically modified (GM) crops are one of the most valuable tools of modern biotechnology that secure yield potential needed to sustain the global agricultural demands for food, feed, fiber, and energy. Crossing single GM events through conventional breeding has proven to be an effective way to pyramid GM traits from individual events and increase yield protection in the resulting combined products. Even though years of research and commercialization of GM crops show that these organisms are safe and raise no additional biosafety concerns, some regulatory agencies still require risk assessments for these products. We sought out to investigate whether stacking single GM events would have a significant impact on agronomic and phenotypic plant characteristics in soybean, maize, and cotton. Several replicated field trials designed as randomized complete blocks were conducted by Monsanto Regulatory Department from 2008 to 2017 in field sites representative of cultivation regions in Brazil. In total, twenty-one single and stacked GM materials currently approved for in-country commercial use were grown with the corresponding conventional counterparts and commercially available GM/non-GM references. The generated data were presented to the Brazilian regulatory agency CTNBio (National Biosafety Technical Committee) over the years to request regulatory approvals for the single and stacked products, in compliance with the existing normatives. Data was submitted to analysis of variance and differences between GM and control materials were assessed using t-test with a 5% significance level. Data indicated the predominance of similarities and neglectable differences between single and stacked GM crops when compared to conventional counterpart. Our results support the conclusion that combining GM events through conventional breeding does not alter agronomic or phenotypic plant characteristics in these stacked crops. This is compatible with a growing weight of evidence that indicates this long-adopted strategy does not increase the risks associated with GM materials. It also provides evidence to support the review and modernization of the existing regulatory normatives to no longer require additional risk assessments of GM stacks comprised of previously approved single events for biotechnology-derived crops. The data analyzed confirms that the risk assessment of the individual events is sufficient to demonstrate the safety of the stacked products, which deliver significant benefits to growers and to the environment.

Transgenic cotton and farmers' health in Pakistan.

Despite substantial research on the economic effects of transgenic insect-resistant Bacillus thuringiensis (Bt) cotton, there is still limited work on this technology's impacts on human health. Due to the inbuilt insect resistance, Bt cotton requires fewer pesticide sprays than conventional cotton, which is not only advantageous from economic and environmental perspectives, but may also result in health benefits for farmers. Using socioeconomic and biophysical data from Pakistan, we provide the first evidence of a direct association between Bt gene expression in the plant and health benefits. A key feature of this study is that Bt cotton cultivation in Pakistan occurs in a poorly regulated market: farmers are often mistaken in their beliefs about whether they have planted Bt cotton or conventional cotton, which may affect their pesticide-use strategies and thus their pesticide exposure. We employ a cost-of-illness approach and variations in the measurement of Bt adoption to estimate the relationship between Bt cotton and farmers' health. Bt adoption based on farmers' beliefs does not reduce the pesticide-induced cost of illness. However, adoption based on measuring Bt gene expression is associated with significant health cost savings. Extrapolating the estimates for true Bt seeds to Pakistan's entire Bt cotton area results in annual health cost savings of around US$ 7 million. These findings have important implications for the regulation of seed markets in Pakistan and beyond: improved regulations that ensure claimed crop traits are really expressed can increase the benefits for farmers and society at large.

Assessment of Genetic Diversity, Population Structure, and Evolutionary Relationship of Uncharacterized Genes in a Novel Germplasm Collection of Diploid and Allotetraploid Gossypium Accessions Using EST and Genomic SSR Markers.

This study evaluated the genetic diversity and population structures in a novel cotton germplasm collection comprising 132 diploids, including Glossypium klotzschianum and allotetraploid cotton accessions, including Glossypium barbadense, Glossypium darwinii, Glossypium tomentosum, Glossypium ekmanianum, and Glossypium stephensii, from Santa Cruz, Isabella, San Cristobal, Hawaiian, Dominican Republic, and Wake Atoll islands. A total of 111 expressed sequence tag (EST) and genomic simple sequence repeat (gSSR) markers produced 382 polymorphic loci with an average of 3.44 polymorphic alleles per SSR marker. Polymorphism information content values counted 0.08 to 0.82 with an average of 0.56. Analysis of a genetic distance matrix revealed values of 0.003 to 0.53 with an average of 0.33 in the wild cotton collection. Phylogenetic analysis supported the subgroups identified by STRUCTURE and corresponds well with the results of principal coordinate analysis with a cumulative variation of 45.65%. A total of 123 unique alleles were observed among all accessions and 31 identified only in G. ekmanianum. Analysis of molecular variance revealed highly significant variation between the six groups identified by structure analysis with 49% of the total variation and 51% of the variation was due to diversity within the groups. The highest genetic differentiation among tetraploid populations was observed between accessions from the Hawaiian and Santa Cruz regions with a pairwise FST of 0.752 (p < 0.001). DUF819 containing an uncharacterized gene named yjcL linked to genomic markers has been found to be highly related to tryptophan-aspartic acid (W-D) repeats in a superfamily of genes. The RNA sequence expression data of the yjcL-linked gene Gh_A09G2500 was found to be upregulated under drought and salt stress conditions. The existence of genetic diversity, characterization of genes and variation in novel germplasm collection will be a landmark addition to the genetic study of cotton germplasm.

Herbicide and insect resistant Bt cotton pollen assessment finds no detrimental effects on adult honey bees.

One important concern regarding the use of transgenic cotton expressing insecticidal toxins from the bacterium Bacillus thuringiensis (Bt) is its potential detrimental effect on non-target organisms. The honey bee (Apis mellifera) is the most important pollinator species worldwide and it is directly exposed to transgenic crops by the consumption of genetically modified (GM) pollen. However, the potential effects of Bt cotton on A. mellifera remain unclear. In the present study, we assessed the effects of two Bt cotton varieties; ZMSJ expressing the Cry1Ac and Cry2Ab insecticidal proteins, and ZMKCKC producing Cry1Ac and EPSPS, on A. mellifera. Feeding on pollen from two Bt cotton varieties led to detection of low levels of Cry toxins (<10 ng/g fresh weight) in the midgut of A. mellifera adults, yet expression of detoxification genes did not change significantly compared to feeding on non-Bt cotton. Binding assays showed no Cry1Ac or Cry2Ab binding to midgut brush border membrane proteins from A. mellifera adults. Taken together, these results support minimal risk for potential negative effects on A. mellifera by exposure to Bt cotton.

Field trial of insect-resistant and herbicide-tolerant genetically modified cotton (Gossypium hirsutum L.) for environmental risk assessment in Japan.

Japan imports cottonseed mainly from Australia and the USA where more than 96% of all cotton varieties grown are genetically modified (GM). GM crops undergo an environmental risk assessment (ERA) under the Law Concerning the Conservation and Sustainable Use of Biological Diversity before import into Japan. Potential adverse effects on biodiversity are comprehensively assessed based on competitiveness, production of harmful substances and outcrossing ability. Even though imported cottonseed is intended for food and feed uses and not for cultivation, the potential risks from seed spillage during transport must be evaluated. In most cases, the ERA requires data collected from in-country field trials to demonstrate how the GM crop behaves in Japan's environment. Confined field trials in Japan were conducted for the ERA of Lepidoptera-resistant and glufosinate-tolerant GM cotton (Gossypium hirsutum L.) lines GHB119 and T304-40. These lines were compared with conventional varieties for growth habit, morphological characteristics, seed dormancy, and allelopathic activity associated with competitiveness and production of harmful substances. Outcrossing ability was not a concern due to the absence of sexually compatible wild relatives in Japan. Although slight statistical differences were observed between the GM line and its conventional comparator for some morphological characteristics, transgenes or transformation were not considered to be responsible for these differences. The trial demonstrated that competitiveness and production of harmful substances by these GM cotton lines were equivalent to conventional cotton varieties that have a long history of safe use, and no potential adverse effects to biosafety in Japan were observed.

Assessment of Gene Flow Between Gossypium hirsutum and G. herbaceum: Evidence of Unreduced Gametes in the Diploid Progenitor.

In the framework of a gene flow assessment, we investigated the natural hybridization rate between Gossypium hirsutum (AADD genome) and G. herbaceum (AA genome). The latter species, a diploid progenitor of G. hirsutum, is spontaneously present in South Africa. Reciprocal crosses were performed without emasculation between G. herbaceum and G. hirsutum Neither examination of the morphological characteristics nor flow cytometry analysis of the 335 plants resulting from the G. hirsutum × G. herbaceum cross showed any hybrid features. Of the 148 plants produced from the G. herbaceum × G. hirsutum cross, three showed a hybrid phenotype, and their hybrid status was confirmed by SSR markers. Analysis of DNA content by flow cytometry and morphological traits clearly showed that two of these plants were triploid (AAD). The third plant had a flow cytometry DNA content slightly higher than G. hirsutum In addition, its morphological characteristics (plant architecture, presence and size of petal spots, leaf shape) led us to conclude that this plant was AAAD thus resulting from fertilization with an unreduced AA gamete of the female G. herbaceum parent. Fluorescent In Situ Hybridization (FISH) and meiotic behavior confirmed this hypothesis. To the best of our knowledge, this is the first description of such gametes in G. herbaceum, and it opens new avenues in breeding programs. Furthermore, this plant material could provide a useful tool for studying the expression of genes duplicated in the A and D cotton genome.

Assessment of allelic diversity among drought-resistant cotton genotypes using microsatellite markers.

Drought, in conjunction with high temperature, is an important environmental constraint to cotton production. Development of cotton varieties with increased tolerance against adverse environmental conditions has been proposed as effective strategy for ensuring reliable yields. In the present study, 30 simple sequence repeat (SSR) primers were used to estimate genetic divergence among 22 cotton genotypes for drought stress tolerance. Genetic diversity is a prerequisite for developing drought resistant cotton genotypes. Eleven SSR primers out of 30 were able to discriminate among the cotton genotypes, implying that 37% of the primers were informative. In total, 41 alleles were detected, with an average of 3.72 alleles per primer. The number of alleles per locus ranged from one (JESPR-284) to six (JESSPR-302), and the allelic diversity in the experimental material was 0.40. Genetic similarity coefficients ranged from 0.87-1.00. The result of principal component analysis confirmed the clustering of 21 cotton genotypes in two groups leaving one genotype (CIM-109) ungrouped. Overall, genetic diversity among the 22 cotton genotypes was low. More polymorphic SSR markers are needed to explore the workable genetic variation among the screened cotton genotypes in future studies.

Assessment of genetic diversity of cotton genotypes for various economic traits against cotton leaf curl disease (CLCuD).

In Pakistan, cotton crop has been under enormous threat of cotton leaf curl disease (CLCuD) over the last four decades. In order to estimate genetic diversity in cotton germplasm CLCuD resistance, we assessed 100 cotton genotypes for their CLCuD resistance/tolerance and other related agronomical traits. Various statistical analytical tools, including correlation analysis, cluster analysis, and principal component analysis (PCA), were used to select the best genotypes. These genotypes can be used in future breeding programs to generate CLCuD resistant varieties. The same set of procedures could be utilized for other diseases in other crops. CLCuD incidence showed a significant negative genotypic correlation with yield-contributing traits followed by a significant negative association for phenotypic correlation. The seed cotton yield showed significant positive genotypic and phenotypic correlations with plant height, number of bolls per plant, and boll weight. From the PCA we identified five principal components (PCs) that explained a significant amount of the variance among the variables, which may be used for selection of cotton genotypes with CLCuD resistance. Of the five PCs, the first four contributed more towards the total variability and had eigenvalues greater than one. The cluster analysis showed that the genotypes in one of the clusters performed particularly well with respect to CLCuD tolerance. These genotypes can be utilized for development of varieties with increased CLCuD tolerance.

Bt cotton and employment effects for female agricultural laborers in Pakistan.

The literature about economic and social impacts of Bt cotton adoption on farm households in developing countries is growing. Yet, there is still uncertainty about wider implications of this technology for rural development, including effects for landless rural laborers. Bt-related yield advantages may lead to intensified production and higher demand for labor. Building on farm survey data collected in Pakistan and using double-hurdle regression models, we analyze employment effects of Bt cotton adoption. Model estimates show that Bt adoption has increased the demand for hired labor by 55%. Manual harvesting, which is common in Pakistan, is a labor-intensive activity primarily carried out by female laborers. Accordingly, gender disaggregation shows that the employment-generating effects are particularly strong for women, who often belong to the most disadvantaged groups of rural societies. These results suggest that Bt technology can contribute to additional employment income for the poor and to more equitable rural development.

Safety assessment of dicamba mono-oxygenases that confer dicamba tolerance to various crops.

Dicamba tolerant (DT) soybean, cotton and maize were developed through constitutive expression of dicamba mono-oxygenase (DMO) in chloroplasts. DMO expressed in three DT crops exhibit 91.6-97.1% amino acid sequence identity to wild type DMO. All DMO forms maintain the characteristics of Rieske oxygenases that have a history of safe use. Additionally, they are all functionally similar in vivo since the three DT crops are all tolerant to dicamba treatment. None of these DMO sequences were found to have similarity to any known allergens or toxins. Herein, to further understand the safety of these DMO variants, a weight of evidence approach was employed. Each purified DMO protein was found to be completely deactivated in vitro by heating at temperatures 55 °C and above, and all were completely digested within 30 s or 5 min by pepsin and pancreatin, respectively. Mice orally dosed with each of these DMO proteins showed no adverse effects as evidenced by analysis of body weight gain, food consumption and clinical observations. Therefore, the weight of evidence from all these protein safety studies support the conclusion that the various forms of DMO proteins introduced into DT soybean, cotton and maize are safe for food and feed consumption, and the small amino acid sequence differences outside the active site of DMO do not raise any additional safety concerns.

Comparative assessment of genetic diversity in cytoplasmic and nuclear genome of upland cotton.

The importance of the cytoplasmic genome for many economically important traits is well documented in several crop species, including cotton. There is no report on application of cotton chloroplast specific SSR markers as a diagnostic tool to study genetic diversity among improved Upland cotton lines. The complete plastome sequence information in GenBank provided us an opportunity to report on 17 chloroplast specific SSR markers using a cost-effective data mining strategy. Here we report the comparative analysis of genetic diversity among a set of 42 improved Upland cotton lines using SSR markers specific to chloroplast and nuclear genome, respectively. Our results revealed that low to moderate level of genetic diversity existed in both nuclear and cytoplasm genome among this set of cotton lines. However, the specific estimation suggested that genetic diversity is lower in cytoplasmic genome compared to the nuclear genome among this set of Upland cotton lines. In summary, this research is important from several perspectives. We detected a set of cytoplasm genome specific SSR primer pairs by using a cost-effective data mining strategy. We reported for the first time the genetic diversity in the cytoplasmic genome within a set of improved Upland cotton accessions. Results revealed that the genetic diversity in cytoplasmic genome is narrow, compared to the nuclear genome within this set of Upland cotton accessions. Our results suggested that most of these polymorphic chloroplast SSRs would be a valuable complementary tool in addition to the nuclear SSR in the study of evolution, gene flow and genetic diversity in Upland cotton.

Global income and production impacts of using GM crop technology 1996-2014.

This paper provides an economic assessment of the value of using genetically modified (GM) crop technology in agriculture at the farm level. It follows and updates earlier annual studies which examined economic impacts on yields, key costs of production, direct farm income and effects, and impacts on the production base of the 4 main crops of soybeans, corn, cotton and canola. The commercialisation of GM crops has continued to occur at a rapid rate since the mid 1990s, with important changes in both the overall level of adoption and impact occurring in 2014. This annual updated analysis shows that there continues to be very significant net economic benefits at the farm level amounting to $17.7 billion in 2014 and $150.3 billion for the 19-year period 1996-2014 (in nominal terms). These economic gains have been divided roughly 50% each to farmers in developed and developing countries. About 65% of the gains have derived from yield and production gains with the remaining 35% coming from cost savings. The technology has also made important contributions to increasing global production levels of the 4 main crops, having, for example, added 158 million tonnes and 322 million tonnes respectively, to the global production of soybeans and maize since the introduction of the technology in the mid 1990s.