转ACO2基因优质棉生长特性及其对田间昆虫群落的影响

Effects of transgenic ACO2 cotton on growth characteristics and insect community

新型转基因棉花的生长特性及其对棉田昆虫群落的影响是转基因棉花环境安全评价的重点内容,也是转基因棉花环境安全评价过程必须评价的内容。选用新型转ACO2基因棉花及其亲本中棉所24为试验材料,于2013年和2014年在河南安阳进行了田间棉花生长势及其对昆虫群落影响的试验。在棉花苗期、蕾期、花铃期和铃期,转基因棉花叶片干重与其亲本均无显著差异,苗期、蕾期叶面积和比叶面积与亲本无显著差异,花铃期、铃期叶面积与比叶面积均显著高于亲本材料,其中2013年分别比对照高27.1%和26.2%,2014年分别高16.0%和19.9%,差异均达显著水平;株高、主茎叶片数、大铃数、小铃数和蕾铃脱落数均与亲本材料相当,但铃期果枝数显著高于亲本材料;3个棉铃虫(Helicoverpa armigera Hubner)发生高峰期,转优质基因棉花对棉铃虫和甜菜夜蛾幼虫校正死亡率与亲本对照材料无显著差异;昆虫群落、害虫亚群落和天敌亚群落昆虫个体总数均显著高于亲本棉田,两年分别比对照高11.5%、10.5%、33.4%和12.0%、8.1%、63.1%,其中2013年差异达显著水平,2014年由于昆虫发生程度总体较轻,差异不显著,但所属"目"、"科"、"种’、生物多样性指数、优势种昆虫及其优势度与其亲本棉田无显著差异,表明外源基因ACO2导入后,对棉田昆虫发生及其群落结构没有影响,棉花生长势无明显优势,但产量构成性状在部分时期增强。上述研究初步明确了新型转基因棉花生存竞争势态和棉田昆虫群落发生规律与动态,可为新型转基因棉花环境安全评价提供理论依据,同时为转基因棉花环境安全评价积累科学数据。

The growth characteristics of transgenic cotton and its effects on the insect communities in cotton fields, which is a key aspect of the evaluation of the environmental safety of transgenic cotton, must be assessed. In this study, we selected the new transgenic ACO2 cotton and its parental CCRI 24 as samples to test cotton growth and changes in insect community in the city of Anyang in Henan province in 2013 and 2014. The results showed that, the leaf dry weight was not significantly different between transgenic cotton and the parental cotton plant at the seeding, bud, flowering or boll stages. In the seedling and bud stage, the leaf area and leaf area ratio of transgenic cotton was not clearly different from the parent. However, in the flowering and boll stage, the ratios were significantly different from those of the parents, specifically 27.1% and 26.2% higher in 2013, and 16% and 19.9% higher in 2014, respectively. There were no significant differences between the transgenic cotton and its parent plant with respect to plant height, leaf number, boll number, bell number or boll abscission number. However, boll branch number in transgenic plants was significantly higher in the parents at the boll stage. During the three adult peaks of occurrence of Helicoverpa armigera, the corrected mortality of cotton bollworm and beet armyworm in transgenic cotton was much lower but was not significantly different from the parental control. The total number of individuals comprising the insect, pest sub, and natural enemy sub communities in the transgenic cotton field were higher than that in parent cotton field, at 11.5%, 10.5%, 33.4% and 8.1%, 63.1%, 12% in 2013 and 2014, respectively, with a significant difference in 2013. Owing to the diminished occurrence of insects in 2014, the difference was not significant. However, the order, family, and species as well the indices for biodiversity, evenness, and dominant species were not significantly different. The above results demonstrated that no obvious advantage was apparent in the new transgenic cotton in respect to growth potential after the ACO2 gene was imported into the cotton. However, the yield component traits in some periods were enhanced. This preliminary study illuminates the rules and dynamics and competition of insect communities as well as the survival of transgenic cotton plants in the field. This could provide a theoretical basis for the evaluation of new transgenic cotton and environmental safety, and this could be the beginning of the accumulation of data concerning both these topics.