摘要
本试验利用精确的改良β—极限糊精法测定杂交稻干种子内部的α—淀粉酶活性,发现始穗期不施用赤霉素所产生的种子内酶的活性很低,特别是在胚乳中α—淀粉酶的活性为○或接近○,制种始穗期喷GA显著提高杂交稻干种子中预存的α—淀粉酶活性,常规施用剂量下产生种子α—淀粉酶的活性比对照高3-10倍,而且大部分集中在胚乳中。4年制种试验中的汕优和威优组合种子α—淀粉酶的活性变化均呈现相同趋势。用多种不同的外源抑制剂在籽粒乳熟-黄熟期施用对汕优63干种子内α—淀粉酶活性有相反的影响,其中以1000 ppm的MH、2.4-D、CCC抑制作用最强,整粒种子内的酶活性为○。此外,杂交稻亲本三系种子中α—淀粉酶的产生对始穗期GA处理的敏感性有明显的差异,其中不育系(V20A)和保持系(V20B)对GA比较敏感,而恢复系(测64)对GA基本不敏感。比较二种不同α—淀粉酶活性测定方法,用改良β—极限糊精法的灵敏度和准确性均明显优于传统的3,5-二硝基水杨酸法。此外,作者还分析了杂交稻内高α—淀粉酶活性对播种品质的不利影响,提出了“胚乳代谢超前性错误”的假说。
A new sensitive and stable method—improved β—limit dextrin method was used to analyseactivity of pre—exesting α—Amylase in rice seeds of four hybrids which were produced fromCross polinated CMS—line treated by gibberellins at early ear emergence in four years trial.Theactivity was also tested for one hybrid (Shanyou 63) which was treated by seven different growthinhibitors and retardants during late milk—ripening or early dough—ripening stages.The re-sults revealed that no or trace α—amylase in endorsperm and also limited activity in whole seedsproduced from non—GAtreated contol,dut significant increases of enzyme activity in en-dorsperm were found in all GA tretments,α—amylase activity reached to the maximum level inthe treaatments of 10 g GA/mu,which was 3—10 times of the whole seeds of non—treated con-tols.Application of inhibitors during seed maturation strongly reduced the enzyme acticity,e.g.in the treatments of 1000 ppm MH,2.4—D or CCC α—amylase activity was not found in thewhole seeds.Using α—amylase as the idicator,experemant also showed that three kinds ofparental lines differed in the responese to GA applied among them CMS line and mainmixintin-ertainer line were sensitive but restorer line very insensitive.The negatives effects of high en-zymic activity on sowing quality of hybird rice seeds sere suggested and a hypothesis of“error ofexceeded endorsperm metablism”was proposed by the authors.
出处
《种子》
CSCD
北大核心
1992年第6期8-12,共5页
Seed
关键词
Α-淀粉酶
种子
外源激素
杂交稻
α—amylase
dry seed
exogenous growth regulators
endorsperm metablism
hybrid rice
