外源GA3、ABA处理对高寒地区甘肃贝母鳞茎休眠的促抑效应

Effect of Exogenous GA3,ABA on the bulb Dormancyof Gansu Fritillaria(Fritillaria przewalskii)

摘要:

以甘肃贝母(Fritillaria przewalskii)鳞茎为试验材料,通过研究鳞茎低温贮藏条件下外源赤霉素(GA₃)和脱落酸(ABA)处理后鳞茎顶芽萌发状况、营养物质以及相关酶活性等生理生化指标的变化,探究外源GA₃及ABA对贝母鳞茎休眠的影响。结果表明:在低温冷藏期间,GA₃处理可以提前解除鳞茎休眠,鳞茎破眠期由对照(CK)的40 d提前至30 d;ABA处理可以延迟贝母解除休眠的时间,鳞茎破眠期由CK的40 d延长至50 d。CK、GA₃处理和ABA处理分别在40、30和50 d时解除休眠。休眠过程中鳞茎内可溶性糖含量和可溶性蛋白含量呈上升趋势;淀粉含量呈下降趋势。在贝母鳞茎解除休眠期间,3种处理鳞茎过氧化物酶(POD)和过氧化氢酶(CAT)酶活性均呈下降趋势,多酚氧化酶(PPO)酶活性呈上升趋势;丙氨酸解氨酶(PAL)酶活性呈下降趋势。低温贮藏下GA₃和ABA处理,鳞茎休眠期分别为40、30和50 d;芽长/鳞茎高在0.66以上可作为判断甘肃贝母鳞茎解除休眠的标准;鳞茎内可溶性糖含量及可溶性蛋白质含量达到峰值的时间,可以作为甘肃贝母鳞茎解除休眠的生理指标。

Abstract:

In this study,the bulb of Gansu fritillaria (Fritillaria przewalskii Maxim) was used as the test materials to research the effect of exogenous Gibberellin acid (GA₃) and Abscisic acid (ABA) on the bulbs dormancy by analyzing the physiological and biochemical indexes such as germination status,nutrients,and related enzyme activities of bulbs during low temperature storage.The result showed that GA₃ treatment could remove the bulb dormancy in advance,the broken dormancy period of bulbs was advanced from 40 d of CK treatment to 30 d;ABA treatment could delay the dormancy time of Gansu Fritillaria,the broken dormancy period of bulbs was prolonged from 40 d of CK treatment to 50 d.CK,GA₃,and ABA treatments were released from dormancy at 40 d,30 d,and 50 d,respectively.The content of soluble sugar and soluble protein in bulbs increased during dormancy,while the starch content decreased.During the release of dormancy,the activity of POD and CAT of the three treatment showed a downward trend,while the activity of PPO showed an upward trend;and the activity of PAL showed a downward trend. Under low temperature storage,the dormancy period of CK,GA₃,and ABA treatments were 40 d,30 d,and 50 d,respectively.,Bud length/bulb height above 0.66 can be used as a criterion for judging that the bulbs of Gansu fritillaria were released from dormancy;the peak time of soluble sugar content and soluble protein content in bulb can be used as the physiological index for dormancy releasing.