施磷量对弱筋小麦扬麦9号籽粒淀粉合成和积累特性的调控效应

以弱筋小麦扬麦9号为材料，在缺磷土壤（速效磷含量4．1mg／kg）上进行施磷量试验，研究施磷量对小麦籽粒淀粉合成、积累及相关酶活性的影响。结果表明。在施磷（P2O5）0～108kg／ha范围内，增加施磷量，籽粒直链淀粉、支链淀粉、总淀粉积累量、积累速率上升，旗叶蔗糖磷酸合成酶（SPS）活性和蔗糖含量提高，籽粒蔗糖合成酶（SS）活性增强。籽粒蔗糖含量提高。籽粒ADPG焦磷酸化酶（AGPP）、可溶性淀粉合成酶（ssS）、束缚态淀粉舍成酶（GBSS）活性提高，成熟籽粒直链淀粉、支链淀粉、总淀粉含量下降。施磷量超过108kg／ha后，直链淀粉、支链淀粉、总淀粉积累量、积累速率及蔗糖含量、SPS、SS、AGPP、SSS、GBSS酶活性呈下降趋势。

Grain Starch Formation Characteristics as Affected by Phosphorus Application in Weak-gluten Wheat Yangmai 9

The effects of phosphorus application amount on grain starch formation in weak-gluten wheat Yangmai 9 were studied in phosphorus-deficient soil.The results showed that with the increasing of phosphorus application amount within 0~108 kg/ha(P_2O_5),the accumulation rates of amylose,amylopectin and starch in grains,sucrose phosphate synthase(SPS) activity and sucrose content in flag leaves,and sucrose synthase(SS) activity and sucrose content in grains would increase.Meanwhile,the activities of AGPP(ADP-glucose pyrophosphorylase),SSS(soluble starch synthase) and GBSS(granule-bound starch synthase) in grains increased,therefore,starch accumulation amount was high.while the contents of amylose,amylopectin and starch at maturity were low.When the phosphorus application was greater than 108 kg/ha,the accumulation rates of amylose,amylopectin and starch,the activities of SPS,SS,,AGPP,SSS,GBSS decreased.