外源赤霉素对小整薯休眠解除中的激素变化及物质转化的影响

Effects of exogenous GA_3 on phytohormones involvement and substances conversion during dormancy releasing of intact small potato

本研究以米拉为试验材料,探讨了不同浓度外源赤霉素(GA3)处理对小整薯休眠解除过程中内源激素的变化及物质转化的影响。结果表明:①外源GA3对小整薯休眠解除过程中几种内源激素含量变化都具有较明显的影响,但不同浓度GA3处理所产生的作用强度和作用时间存在差异。高浓度(4×10-4mL/L)处理对内源GA3、IAA和ZT的影响作用大于低浓度(2×10-4mL/L)处理,而对ABA和JAs的影响差异不明显;②高浓度(4×10-4mL/L)GA3处理产生作用的时间均比低浓度(2×10-4mL/L)处理提前,持续时间更长;③外源GA3在一定程度上影响了小整薯休眠解除中淀粉的分解和可溶性糖的消耗,高浓度的外源GA3促进了淀粉的分解,但降低了可溶性糖的含量。综合来看,取合理浓度的上限有利于小整薯休眠的解除。

The potato cultivar Mira was selected as the materials in this research. The involvement of endo-hormones and substances during the process of dormancy releasing of intact small potato were determined after being sprayed with different concentrations of exogenous gibberellin（ GA3 ）. The resuhs showed that： （i）The exogenous GA3 with the different concentrations had obvious and different influences including function intensity and timing on the content of endo-hormones. The influence of high concentration of 4 ×10^-4mL/L GA3 on content of GA3 , IAA and ZT was stronger than that of the low concentration of 2 ×10^-4mL/L, but was not of obvious difference on ABA and JAs content. （ii） The treatment of 4 ×10^-4mL/L GA3 played the important role much earlier than that of 2 ×10^-4mL/L,and lasted longer, （iii）The decomposition of starches and conversion of dissoluble sugars of the whole small potato occurred with the sprayed GA3 to the different extent. The treat- ment of 4×10^-4mL/L GA3 promoted the decomposition of starches and reduced the content of dissoluble sugars. So took comprehension to see ,selecting the upper limit of reasonable range concentration was advantage to dormancy release of intact small potato .