摘要
以协青早(XQZ)及其低植酸突变系(os-lpa1)为材料,通过对灌浆过程籽粒中植酸含量、蔗糖和淀粉积累变化动态的比较分析,并结合叶、茎、鞘等器官中碳水化合物的转运和籽粒淀粉合成代谢有关关键酶生理活性的测定,对os-lpa1灌浆充实不良、千粒重明显降低的生理原因进行了分析。结果表明,灌浆期os-lpa1剑叶、茎、鞘等器官中的蔗糖和可溶性总糖含量均高于其对照亲本XQZ,但os-lpa1籽粒中的淀粉积累量却明显降低。胚乳中ADPG焦磷酸化酶(ADPG-Ppase)和淀粉磷酸化酶(SPase)的活性降低,可能是os-lpa1灌浆充实不良、籽粒淀粉积累量明显下降的主要原因之一。此外,os-lpa1灌浆期间叶鞘中的蔗糖磷酸合酶(SPS)和果糖-1,6-二磷酸酶(FBPase)活性也显著低于其相应灌浆期的对照亲本XQZ,导致茎鞘等器官中淀粉积累量增多和"流"不畅,这可能也是其产量水平降低的一个重要因素。
For recognizing the physiological effects of phytic acid （PA） on rice plumpness and grain weight, rice cultivar XQZ and its low PA mutant （os-lpa1） were applied to compare the difference in the changing patterns of PA, sucrose content and starch accumulation at filling stage, translocation of carbohydrates in different organs （flag leaf, culm, and sheath） and the activities of some key enzymes involved in grain starch synthesis metabolism. The results showed that os-lpa1 had higher contents of sucrose and total soluble sugar, and more starch accumulation in the flag leaf, culm, and sheath, but lower starch synthesis in grains at tilling stage compared to XQZ. The relatively lower activities of ADPG-Ppase and SPase in tilling grains were probably responsible for poor plumpness and low starch accumulation in os-lpa1. Additionally, compared with XQZ, os-lpa1 exhibited lower ac- tivities of SPS and FBPase in sheath at tilling stage, resulting in an excessive accumulation of starch and blocked flows of assimilates, which could be one of the reasons for the descending yield of os-lpa1.
出处
《作物学报》
CAS
CSCD
北大核心
2008年第11期1977-1984,共8页
Acta Agronomica Sinica
基金
国家自然科学基金项目(30671228
30471020)
关键词
水稻
植酸突变
淀粉积累
酶生理
Rice （Oryza sativa L.）
PA （phytic acid） mutant
Grain starch accumulation
Enzymes
