不同施磷量对小麦(Triticum aestivum L.)种子成熟后萌发特性的影响

Effects of different phosphorus application levels on the germination characteristics of the harvested seeds in wheat(Triticum aestivum L.)

为研究小麦(Triticum aestivum L.)生长过程中不同施磷水平对收获后种子的萌发特性的影响,本研究选用冬小麦品种'新冬20号'和'新冬23号',在3种施磷水平(对照0 kg/hm2、低磷105 kg/hm2、高磷210 kg/hm2)下收获的小麦籽粒为材料,通过扫描电镜观察种子萌发过程中胚乳淀粉粒的形态变化,比较不同发芽时期籽粒淀粉酶和酸性磷酸酶活性以及胚根和胚芽发育状况。结果表明:2个参试品种发芽6 d时,低磷处理下的籽粒淀粉粒降解程度高于对照和高磷,低磷条件下的籽粒α-淀粉酶活性显著高于对照和高磷;'新冬20号'和'新冬23号'小麦籽粒发芽6-8 d,低磷处理下的胚根长显著高于高磷;发芽8 d,新冬20号高磷处理下的单株干重分别为低磷和对照的86.3%和90.7%,新冬23号高磷处理下的单株干重分别为低磷和对照的90.6%和84.5%。2个品种高磷处理下的单株干重均显著低于对照和低磷。这说明小麦生长过程中适宜的施磷量(低磷)有利于种子发芽过程中胚根的生长和干物质的积累,过量施磷则有抑制作用。

The aim of this study was to study the effects of different phosphorus application （CK：0 kg/hm, LP： 105 kg/hm, HP： 210 kg/hm） on the germination characteristics of the harvested wheat seeds during wheat plants development. Two winter wheat varieties were used to observe the changes of starch granule morphology, enzyme activities of amylase and acid phosphatase, and the seedling development. The results showed that at 6 days post germination （DPG）, the hydrolysis degree of starch granules under the condition of low phosphorus （LP） was more obvious than that of the CK and higher phosphorus （HP） conditions in Xindong 20 and Xindong 23 wheat. Whereas the enzyme activities of grain a-amylase under the condition of LP was significantly higher than that of the CK and HP conditions. During 6 DPG to 8 DPG, the root length from LP treatment was significantly longer than that of the HP condition. At 8 DPG, the dry weight per plant of Xindong 20 under HP treatment accounts for 86.3% and 90.7% of LP and control treatments, respectively. The dry mass per plant of Xindong 23 under HP treatment accounts for 90.6% and 84.5% of LP and control treatments, respectively. The dry weight per plant of two varieties under HP condition was significantly lower than that of the control and LP condition. Conclusively, during the wheat plants development, the appropriate amount of phosphorus application is beneficial to the radicle growth during seed germination the dry mass accumulation, while excessive application of phosphorus has an inhibitory effect.