干旱条件下单用草甘膦或添加营养元素作为甘蔗化学催熟剂的效应

The Effects of Sole Glyphosate or Adding Nutrient as Chemical Ripener in Sugarca ne ( Saccharum officinarum L.) under Drought Condition

中熟甘蔗品种桂糖 15号在生长后期分别用草甘膦、草甘膦 +KH2 PO4 、草甘膦 +H3BO3和草甘膦 +KH2 PO4 +H3BO3进行叶面喷施。结果表明 :在严重干旱的条件下 ,单用草甘膦处理对甘蔗生长和蔗茎糖分积累都不利 ,而添加营养元素的处理 ,尤其是草甘膦 +H3BO3处理 ,可缓解草甘膦对生长代谢的抑制效应 ,使叶片 Mg2 +- ATP酶和 NADP-苹果酸酶活性以及水分和叶绿素含量下降的幅度减小 ,而进一步抑制了酸性转化酶活性 ,提高过氧化物酶、多酚氧化酶和中性转化酶活性以及无机磷和蔗糖含量 ,显著提高甘蔗蔗糖分 ,改良甘蔗品质 。

Foliar spray with glyphosate, glyphosate+KH 2PO 4, glyphosate+H 3BO 3 and gl yphosate+KH 2PO 4+H 3BO 3 was conducted respectively at the late growth stag e of Guitang 16 an intermediate cultivar of sugarcane ( Saccharum officinarum L.). The results showed that the treatment with sole glyphosate was unfavourab l e for both growth and sugar accumulation of sugarcane and the germination of nex t ratoon crop under the serious drought condition. Adding KH 2PO 4 and/or H 3 BO 3 into glyphosate alleviated the inhibition of metabolism related to growth due to glyphosate, and the treatment of glyphosate+H 3BO 3 was the best in the study. This treatment increased the activities of Mg 2+ ATPase and NADP malic enzyme, and the contents of water and chlorophyll but decreased the activi ty of acid invertase in the leaves as compared with the treatment by sole glypho sate alone. It also showed higher activities of peroxidase, polyphenol oxidase a nd neutral invertase, and higher contents of inorganic Pi and sucrose in the lea ves as compared with the control and all treatments. As a result, it significant ly increased the sucrose content in cane, improved the quality of cane while kee ping the same yield of cane, and promoted the germination of ratoon crop as comp ared with the control.