摘要
以扬稻6号和粳稻941为材料,通过盆栽试验,研究了不同施氮处理对水稻颖果淀粉积累和相关酶活性的影响。结果表明,增加穗肥施氮量显著降低颖果中的可溶性糖含量,淀粉含量有降低的趋势,但不明显。颖果中直链淀粉和支链淀粉含量随粒重的增加而上升,二者积累具有同步性;增加穗肥施氮量能显著降低颖果中直链淀粉含量,并使颖果中直链/总淀粉的比例降低,其效果要好于分蘖期施氮。分蘖期或孕穗期增施氮肥可以显著提高灌浆中、后期颖果中的ADPG焦磷酸化酶(AGP)、可溶性淀粉合酶(SSS)和淀粉分支酶(SBE)的活性,降低颖果中淀粉粒结合型淀粉合酶(GBSS)的活性。就施氮时期来看,孕穗期施氮(LH)对这些酶的促进或抑制效果好于分蘖期施氮(HL)。
Starch accumulation is the main event in the developing rice grain, and the activities of key enzymes involved in starch synthesis are the important factors affecting the grain filling. N-fertilizer can regulate the plant growth, flower emergence, grain yield and quality, while the effects of N-fertilizer on starch accumulation and the activities of key enzymes in rice grains are rarely known. In this study, two rice cultivars, Yangdao 6 and Jingdao 941, were used as materials to study the effects of nitrogen on starch accumulation and the activities of related enzymes involved in starch synthesis. The results indicated that increased panicle N-fertilizer could significantly decrease the soluble sugar in the developing caryopsis, while the starch content reduced slightly. The amylose and amylopectin contents in the caryopsis increased synchronously with the raising of grain weight. When the panicle N-fertilizer was added, the amylose content in caryopsis as well as the content ratio of amylose to total starch decreased observably. During the development of rice caryopses, the activities of ADP-glucose pyrophosphorylase （AGP）, granule-bound starch synthase （GBSS）, soluble starch synthase （SSS）, and starch branching enzyme （SBE） in endosperm changed as single peak curve. That was, the enzyme activities increased at the early stage of grain filling, till their peak at 10-15 d after flowering, then depressed. Application of nitrogen fertilizer could improve the activities of AGE SSS, and SBE in rice caryopsis at middle and late filling stages, while decrease GBSS activity at early and middle filling stages. And the effect of the N fertilized at the booting stage was superior to that at the tilling stage.
出处
《作物学报》
CAS
CSCD
北大核心
2008年第12期2168-2175,共8页
Acta Agronomica Sinica
基金
国家自然科学基金项目(30471045)
国家"十一五"科技支撑计划重大项目(2006BAD02A03)
江苏省高校自然科学基金项目(06KJB210127)
江苏省青蓝工程骨干教师资助项目
高邮市国家农业综合开发土地治理项目(2007)
关键词
氮肥
水稻
颖果
淀粉积累
酶活性
Nitrogen fertilizer
Rice
Caryopsis
Starch accumulation
Enzyme activity
