Schematic of agricultural practices applied to the 3 cotton fields during this study (2007–2010).

<p>Patterned bars represent different pesticides, with target pest listed in central column. Black circles with ‘F’ indicate fertilizer application, and black arrows with ‘S’ represent sampling times. Symbol placement is indicative of timing but is not precise.</p

Enhanced yield performance of transgenic <i>cry1C*</i> rice in saline-alkaline soil

China has a large area of saline-alkaline land that can be utilized for the cultivation of transgenic rice. Therefore, the growth and reproductive behavior of transgenic rice are not only a problem for production that needs to be resolved, but also an important aspect of environmental risk assessment for saline alkali soil. In the present study, an insect-resistant transgenic cry1C* rice, T1C-19, was grown in farmland and saline-alkaline soils. The transcription and translation of the exogenous cry1C*, and vegetative and reproductive fitness, such as plant height, tiller number, biomass, filled grain number and weight per plant, were assessed. Our findings indicated that the transcription and translation of exogenous cry1C* gene in T1C-19 rice grown in saline-alkaline soil were lower than that grown in farmland; however, the correlation was not significant. The vegetative and reproductive growth abilities of T1C-19 were lower than that of the parental rice, Minghui63 (MH63), in farmland. In alkaline-saline soil, except for tiller number and biomass, there were no significant differences between T1C-19 and MH63 in other vegetative indices. In contrast, the reproductive indices of T1C-19 were significantly higher than those of MH63. The results suggested that T1C-19 had a strong reproductive capacity, and significantly reduced the loss of yield caused by insects, thereby leading to a higher yield than that of MH63 grown in saline-alkaline soils. This may promote the cultivation of saline-alkaline soil to permit farming of T1C-19 in China in the future, despite the possible increased ecological risks.</p

The soil nematode composition in 3 cotton fields during 2009–2010.

<p>The soil nematode composition in 3 cotton fields during 2009–2010.</p

Generalized Linear Mixed Model (GLMM) results for the overall effects on soil nematode trophic groups.

<p>Generalized Linear Mixed Model (GLMM) results for the overall effects on soil nematode trophic groups.</p

Number of <i>Filenchus</i> in 3 cotton fields at different sampling times.

<p>Error bars indicate standard errors (n = 3). Different letters above bars denote a statistically significant difference between the means of the fields.</p

Number of <i>Helicotylenchus</i> in 3 cotton fields at different sampling times.

<p>Error bars indicate standard errors (n = 3). Different letters above bars denote a statistically significant difference between the means of the fields.</p

Factor loading graph of principal component analysis of soil nematode generic composition in cotton fields at different sampling times.

<p>Factor loading graph of principal component analysis of soil nematode generic composition in cotton fields at different sampling times.</p

Composition and abundance (individual/100 g dry soil) of the soil nematodes extracted from different samples from 3 cotton fields during 2009–2010. <i>P_i</i> denotes the proportion of soil nematode individuals in each treatment.

<p>Composition and abundance (individual/100 g dry soil) of the soil nematodes extracted from different samples from 3 cotton fields during 2009–2010. <i>P_i</i> denotes the proportion of soil nematode individuals in each treatment.</p

Changes in the composition of nematode trophic groups (%) among different cotton fields at different sampling times for the 2-year survey (mean±SE).

<p>Mean values and standard error of 3 replicates are presented. Use of the same letter as a superscript indicates that variable means did not differ significantly among different treatments at each sampling date (<i>p</i>>0.05).</p

Generalized Linear Mixed Model (GLMM) results for overall effects on the numbers of soil nematodes.

<p>Generalized Linear Mixed Model (GLMM) results for overall effects on the numbers of soil nematodes.</p