转基因抗虫棉根系分泌物对棉花黄萎病菌生长的影响

转基因抗虫棉的抗病性下降已成为制约我国棉花生产的重要因素之一.以转基因抗虫棉及其亲本非转基因棉花对照为材料，研究转基因抗虫棉根系分泌物对棉花黄萎病菌孢子萌发和菌丝生长的影响，并对其根系分泌物中氨基酸及糖类的组成和含量进行了测定.结果表明：与亲本非转基因棉相比，2种转基因抗虫棉对棉花黄萎病菌的抗性下降，转基因抗虫棉的根系分泌物对黄萎病菌孢子萌发和菌丝生长均具有促进作用.与亲本常规棉中23相比，转基因双价抗虫棉中41根系分泌物中多了甲硫氨酸和赖氨酸，并且天冬氨酸、谷氨酸、丝氨酸、丙氨酸、缬氨酸、亮氨酸、酪氨酸的含量显著升高.泗棉三号与单价抗虫棉GK12的根系分泌物中虽然含有相同的氨基酸组分，但GK12的根系分泌物中酪氨酸、缬氨酸、亮氨酸的含量显著下降.中41根系分泌物中检测出4种糖类，而中23中仅检测出葡萄糖.抗虫棉GK12和泗棉三号根系分泌物中都检测出4种糖类，但其含量差异明显.

Effects of transgenic insect-resistant cotton root exudates on the growth of Verticillium dahliae Kleb.

The decline of disease resistance of transgenic insect-resistant cotton has bec ome one of the important factors restricting China cotton production. With two t ransgenic insect-resistant cotton varieties and their parental conventi onal cotton lines as test materials, the effects of their root exudates on the s pore germination and mycelial growth of Verticillium dahliae Kleb were studi ed, and the components and contents of the amino acids and sugars in the exudate s were determined. Comparing with their parental lines, the two transgenic insec t-resistant varieties had a declined resistance against V. dahliae, and the ir root exudates had promotion effects on V. dahliae spore germination and mycel ial growth. The root exudates of transgenic cotton Zhong-41, compared with thos e of its parent line Zhong-23, contained two additional amino acids Met and Lys , and the contents of Asp, Glu, Ser, Ala, Val, Leu, and Tyr were significantly h igher. Though the components of amino acids in the root exudates of Simian-3 an d transgenic cotton GK-12 were the same, the Tyr, Val, and Leu contents in the root exudates of transgenic cotton GK-12 were significantly lower. Four kinds o f sugar were detected in the root exudates of Zhong-41, while only glucose was detected in the root exudates of Zhong-23. These four kinds of sugar were also detected in the root exudates of Simian-3 and GK12, but their contents differed significantly.