Abstract: Effect of phytic acid and chlorine ion on the rice grain quality was studied with a early rice variety Yuanfengzao (Oryza sativa L.). The amylum hydrolase activity could obviously be inhibited by foliage spraying phytate on rice leaves during heading to maturing period. The results indicated that amylase activity which lead to starch decomposition reaction can be declined and amylosynthetase can be decreased relatively by phytic acid. It could affect starch synthesis and improve rice grain quality. When applied concentrations of phytic acid are 50, 100 mg/kg during the full heading period, broken kernels yield of the treated rice is 2.8-3.1 percentage point lower than that of the control. However, head milling rice yield is 5-7 percentage point higher than control. Meanwhile, chalkiness score and milky white grain yield are also lower than control. For alkali digestibility and amylose content also can be affected by phytic acid. On the other hand, the results show, as an activitor of diastase, chlorine ion can inhibite activity of amylosynthetase and appear inverse effect to grain quality.

Key words: amylase, amylosynthetase, phytic acid, rice grain quality

摘要： 以原丰早为材料进行了在不同时期施用植酸与氯离子的试验。在水稻抽穗至成熟期间叶面喷施植酸，能抑制水解酶类的活性，减弱淀粉酶分解淀粉的反应，提高淀粉合成酶的活性，有利于淀粉合成，改善稻米品质。水稻齐穗期叶面喷施50、100 mg/kg 两种浓度的植酸，碎米率的平均值比对照低2. 8～23. 1个百分点，整精米率上升5～7个百分点；垩白等级、垩白率降低，乳白米粒减少，与对照相比差异显著；对碱消值、直链淀粉含量亦有影响。氯离子作为淀粉酶的激活剂，喷施后能抑制淀粉合成酶的活性，对稻米品质呈逆向效应。

关键词: 植酸, 淀粉酶, 淀粉合成酶