不同生育阶段棉铃分泌物对棉铃疫菌和炭疽菌的影响

EFFECTS OF EXUDATES OF COTTON BOLL OF DIFFERENT AGE ON PHYTOPHTHORA BOEHMERIAE AND COLLETOTRICHUM GOSSYPII

本研究对棉花早熟品种TX—5、TX—8及中早熟品种中—12,以4个播种期进行试验,对各品种不同生育阶段棉铃分泌物中的糖,单宁、棉酚的含量及其对棉铃疫霉菌(Phytophthora boehmeriae)和炭疽菌(Collectotrichum gossyptii)生长的影响作了分析。结果表明:当棉铃增大期、充实期铃表分泌的棉酚、单宁含量较高,在这一阶段,单宁、棉酚对棉铃疫霉菌(P.boehmeriae)和炭疽菌(C.gossypii)起着重要的抑制作用;钾对次生物质代谢起着促进作用。研究认为:选用早熟品种适期晚播,使疫菌和炭疽菌侵染高峰期,正值铃表单宁、棉酚含量最高阶段,能有效的减轻棉铃病害的发生,从而提高棉花的产量与品质。

Three cultivars of cotton(TX—5,TX—8 and Zhong—12)were sown at four stages.Con tents of sugar,tannin and gossypol in exudates of cotton boll of different age were analysed.It was found that contents of tannin and gossypol reached the highest level on the 10th and 30th days of the boll stage and P.boehmeriae and C.gossypii were meantime suppressed effectively. This suggests that late sowing of the early maturing cotton cultivars may result in the highest exudation of tannin and gossypol meeting the high occurence of infection by P.boehmeriae and C.gossypii and thereby reduced the losses caused by the boll rots.