【摘要】 研究棉花打顶后倒四叶内源激素和养分的关系表明:棉花打顶后,植株叶片的激素平衡关系被破坏,ABA/IAA和ABA/CTK比值上升,CTK含量下降。比值的变化降低了叶片中N和P的含量,但对K的变化无明显影响;降低了茎中N的含量,但对P和K的变化无明显影响;增加了生殖器官中的N,但对P,K的变化无明显影响。涂抹NAA能使叶片和茎中N下降的幅度缓解或加强。打顶对叶片的衰老影响最为明显。它将使棉株整体(尤其是营养器官)由正常生长向衰老方向转化,叶片内氮素营养减少,叶绿素含量下降。更多还原

【Abstract】 In this paper,the change of hormone and nutrient absorption of cotton in fourth leaves from the top after decapitation is analyzed.The results reveal that,after cotton are decapitated,the hormone balance in fourth leaves from the top is changed,the ABA/IAA and ABA/CTK ratios are increased,and the CTK content is decreased.Such changes result in a reduction of N and P contents in cotton leaves,but the change of K content is not so significant;N content in cotton stems is decreased,but the change of P and K contents in cotton stems is not so significant;N content in reproductive organs is increased,but the change of P and K contents in reproductive organs is not so significant.NAA can alleviate the reduction of N content in cotton leaves and stems.Cotton decapitation significantly accelerates the aging process of cotton leaves and makes the whole plants(especially the nutrition organs) transiting from normal growth towards aging process.Thus,the N content and chlorophyll content in cotton leaves are decreased.更多还原