甘蔗应用乙烯利增产增糖的机理研究

Mechanism of ethephon on increasing cane yield and sucrose % cane in sugarcane

为了探明乙烯利对甘蔗增产增糖的生理机理,分别从群体、个体、器官、细胞到分子水平进行了全面分析,结果认为:乙烯利处理首先是诱导了编码ACC合成酶和ACC氧化酶基因表达,使甘蔗组织内出现一个乙烯释放高峰,它改变了蔗株体内五大内源激素之间的平衡关系,从而影响到许多功能基因的表达,因此影响到各种生理代谢,影响细胞的分裂、伸长和分化,并进一步影响到器官、组织的发育和蔗株的生长。叶面喷施乙烯利后诱发的过氧化物酶和IAA氧化酶活性提高加快了IAA的氧化分解,使组织中的IAA含量降低,从而使蔗株地上部分的生长受到暂时抑制。但是,组织内较高的乙烯浓度会反过来加速内源IAA的合成,因此短暂抑制过后蔗株能够快速生长。如果所用的乙烯利浓度过高,会导致蔗株生长长时间受阻,但在糖分积累时期,这种情况有利于蔗茎中的蔗糖积累,因此起到催熟增糖作用。

A series of investigations was conducted at levels of population, plant,organ,cell and molecule to illustrate the mechanism of ethepben on increasing cane yield and sucrose % cane in sugarcane. It was found that the ethephon treatment first induced the expression of the genes encoding ACC synthase and ACC oxidase and resulting in an ethylene releasing peak inside the tissues,which changed balances of the five endo-hormoues,which affected the expression of various functional genes and so affecting the division,elongation and differentiation of the cells that leaded to the direct changes in the development of organs and tissues and the growth of the plants. The increases of perexidase and IAA oxidase activities induced by foliar spray of ethephou promoted the oxidation and degradation of IAA ,which led to the decrease of IAA in the tissues so resulting in temporary inhibition of the growth of the above-ground part of the plants. However,the relative high concentration of ethylene speeded up the synthesis of IAA inside the tissues,whlch explained the fast growth after a short inhibition. If the applied ethephon concentration is too high, the plant growth would be inhibited for a long time. However, this situation would he good for sugar accumulation in the stalks during sugar accumulation stage, so ethephon could be used as the ripener of sugarcane.