转基因抗草甘膦大豆的光合及荧光特性

Photosynthetic and chlorophyll fluorescence characteristics of transgenic glyphosate-tolerant soybean

本文比较了转基因抗草甘膦大豆40-3-2与常规栽培大豆荷豆13在光合、叶绿素荧光以及繁殖适合度参数上的差异,以评价在我国农田生境中转基因大豆相对于本土栽培种是否具备更强的入侵性或杂草化特征。结果表明,40-3-2花期叶片净光合速率低于同期的荷豆13,但水分利用策略优良,即蒸腾速率低、水分利用效率高,环境适应能力强。叶绿素荧光测定显示40-3-2全天只有轻微的光抑制现象,其光系统Ⅱ能够在高温和强光照条件下维持较高的光化学效率,而荷豆13叶片在正午时有强烈的光抑制。尽管如此,在没有除草剂选择压条件下,在生长和繁殖适合度上40-3-2相对于荷豆13无竞争优势,入侵性风险较低。

The photosynthetic characteristics,chlorophyll fluorescence and growth fitness parameters of transgenic glyphosate-tolerant soybean 40-3-2 were investigated to assess the risk of invasive weed population to the ecological environment of China.The results indicated that transgenic 40-3-2 leaves in flowering stage had lower net photosynthetic rate（Pn） than that of cultivated soybean Hedou 13,but had superior water utility efficiency（WUE） with higher drought adaptability.Its chlorophyll fluorescence showed a low level of photoinhibition（lower Fv/Fm） and higher PSII photochemistry efficiency all day.On the contrary,the cultivated Hedou 13 had severely reduced Fv/Fm value at midday.Even so,there was no yield advantage of transgenic 40-3-2 observed in field when herbicide selective pressure was absent.These results suggested that the transgenic soybean 40-3-2 has little potential to be invasive.