Fitness changes in wild soybean caused by gene flow from genetically modified soybean

Abstract Background Crop-wild hybridization has generated great concerns since gene flow can be an avenue for transgene escape. However, a rather limited number of studies on risk assessment regarding the dispersion of transgenes from GM soybean to populations of its wild relatives have been previously conducted. Results The results of the 3-year experiment demonstrated that hybrids between GM soybeans and wild soybean had lower seed germination and higher seed productivity than GM soybean. Both of these features of hybrid (especially F2 and F3) were similar to those of wild soybean. Furthermore, the foreign protein was stably expressed in hybrid EPSPS positive plants; however, no difference was observed in agronomic measurements between hybrids that are glyphosate sensitive or resistant, homozygous or heterozygous for the transgene, indicating that the presence of the EPSPS transgene does not affect the vigor of hybrid. In contrast, hybridization between GM soybean and wild soybean may have more impact on hybrid growth and fecundity, this increase in biomass and yield confers a potential competition benefit to hybrids. Conclusions Gene flow from GM soybean to wild soybean has the potential to promote the adaptability of hybrids and may increase the possibility of dispersal of transgenes in wild soybean relatives

Phylogenetic Analyses and Transcriptional Survey Reveal the Characteristics, Evolution, and Expression Profile of NBS-Type Resistance Genes in Papaya

Carica papaya maintains an abnormally small but complete NLR family while showing weak disease resistance. To better understand their origin, evolution, and biological function, we identified 59 NLR genes via a customized RGAugury and investigated their characteristics, evolutionary history, and expression profiles based on the improved papaya genome and large-scale RNA-seq data. The results indicated that duplication is a major evolutionary force driving the formation of the papaya NLR family. Synteny analyses of papaya and other angiosperms showed that both insertion and inheritance-derived NLRs are present in papaya. Transcriptome-based expression and network analyses revealed that NLRs are actively involved in biotic stress responses. For example, a papaya-specific inserted TNL was up-regulated strongly by the fungal infection. Both transcriptome and qRT-PCR analyses confirmed the expression divergence of an RNL and an RCNL, a pair of tandem duplication genes involved in different co-expression modules. Furthermore, we observed an inserted gene cluster composed of five duplicated CNLs, showing dosage effects and functional differentiation of disease-resistance genes during evolution. This research will enhance our knowledge of the special NLR family in papaya, which may serve as a model plant for disease-resistance genetic studies

A Comprehensive Assessment of the Effects of Transgenic Cry1Ac/Cry1Ab Rice Huahui 1 on Adult <i>Micraspis discolor</i> (Fabricius) (Coleoptera: Coccinellidae)

<div><p><i>Micraspis discolor</i> (Fabricius) (Coleoptera: Coccinellidae) is a widely distributed coleoptera predator in southern Asia in rice ecosystem, and adult <i>M</i>. <i>discolor</i> feed on both rice pollen and soft-bodied arthropods. Bitrophic bioassay and tritrophic bioassay were conducted to evaluate the potential impact of Cry1Ac/Cry1Ab-expressing rice Huahui 1 and its non-transgenic counterpart Minghui 63 on fitness parameters of adult <i>M</i>. <i>discolor</i>. The results showed that the survival, and fecundity of this beetle’ adults were not different when they fed on Bt rice or non-Bt rice pollen or <i>Nilaparvata lugens</i> (Stål) reared on <i>Bt</i> rice or non-<i>Bt</i> rice. Toxicity assessment to ensure <i>M</i>. <i>discolor</i> adults were not sensitive to Cry1Ab or Cry1Ac protein independent from the pollen background, <i>M</i>. <i>discolor</i> adults were fed with an artificial diet containing Cry1Ac, Cry1Ab or both protein approximately 10 times higher concentration than in Huahui 1 rice pollen. No difference was detected for any of the life-table parameters tested between Cry protein-containing and pure diet. Artificial diet containing E-64 (N-(trans-Epoxysuccinyl)-L-leucine 4-guanidinobutylamide) was included as a positive control. In contrast, the pre-oviposition and fecundity of <i>M</i>. <i>discolor</i> were significantly adversely affected by feeding on E-64-containing diet. In both bioassays, the uptakes of Cry protein by adult <i>M</i>. <i>discolor</i> were tested by ELISA measurements. These results indicated that adults of <i>M</i>. <i>discolor</i> are not affected by Cry1Ab- or Cry1Ac-expressing rice pollen and are not sensitive to Cry protein at concentrations exceeding the levels in rice pollen in Huahui1. This suggests that <i>M</i>. <i>discolor</i> adults would not be harmed by Cry1Ac/Cry1Ab rice if <i>Bt</i> rice Huahui 1 were commercialized.</p></div

Effect of feeding a pure artificial diet or artificial diet with purified Cry1Ab, Cry1Ac and E-64 provided on different life-table parameters of adult <i>Micraspis discolor</i>.

<p>Effect of feeding a pure artificial diet or artificial diet with purified Cry1Ab, Cry1Ac and E-64 provided on different life-table parameters of adult <i>Micraspis discolor</i>.</p

Different abundance of 3 predators in booting(I), tillering(II), early-blooming(III), blooming(IV) and filling(V) phases in Spring, Summer and Autumn rice seasons in 2013.

<p>Different abundance of 3 predators in booting(I), tillering(II), early-blooming(III), blooming(IV) and filling(V) phases in Spring, Summer and Autumn rice seasons in 2013.</p

Impact of the consumption of pollen from Cry1Ab /Cry1Ac-expressing <i>Bt</i> rice or the corresponding non-transformed rice plant on different life-table parameters of adult <i>Micraspis discolor</i>.

<p>Data are provided as mean (±SE).</p

Mean (±SE) daily fecundity of <i>Micraspis discolor</i> fed an artificial diet containing 150 mg/g Cry1Ab, 120 mg/g Cry1Ac, 150 mg/g Cry1Ab and 120 mg/g Cry1Ac or 25 mg/g E-64(positive control) per g dry weight of artificial diet.

<p>Pure artificial diet served as a negative control.</p

Impact of the consumption of BPH reared on Cry1Ab /Cry1Ac-expressing <i>Bt</i> rice or the corresponding non-transformed rice plants on different life-table parameters of adult <i>Micraspis discolor</i>.

<p>Data are provided as mean (±SE).</p