AlA对冬小麦不同粒位籽粒灌浆影响的动态模拟及特征分析

以百农矮抗58为材料,采用大田试验的方法,研究了在始穗期喷施不同浓度(10mg/L、30 mg、50 mg/L)的5-氨基乙酰戊酸(5-Aminolevulinic acid,ALA)对冬小麦不同粒位籽粒灌浆特性的影响.应用Richards方程对10～50 mg/L ALA处理下冬小麦3个粒位(第Ⅰ、Ⅱ、Ⅲ粒位)的籽粒灌浆过程进行了模拟.建立在Richards方程基础上的籽粒生长分析显示:与对照相比,10～50 mg/L ALA处理使第Ⅰ和第Ⅲ粒位的千粒重分别增加了1.3～2.4g、3.4～4.7,较对照差异显著,第Ⅱ粒位的粒重与对照差异不显著;10～50 mg/L ALA处理使冬小麦3个粒位籽粒的平均灌浆速率和最大灌浆速率增大,灌浆活跃持续期延长,到达最大灌浆速率的时间提前.阶段灌浆特征参数的比较表明,在籽粒灌浆的渐增期,10～50 mg/L ALA处理使冬小麦3个粒位籽粒的平均灌浆速率增加,灌浆持续期缩短;在籽粒灌浆的快增期,使3个粒位籽粒的平均灌浆速率增加,灌浆持续期延长.在籽粒灌浆的缓增期,使强势粒(第Ⅰ、第Ⅱ粒位)的平均灌浆速率减小,灌浆持续期延长,但使弱势粒(第Ⅲ粒位)的平均灌浆速率增加,灌浆持续期延长.表明在灌浆的前期和中期,10～50 mg/L ALA处理可促进各粒位籽粒提早启动灌浆,并提高其灌浆速率,在灌浆后期减弱了强势粒对弱势粒籽粒灌浆充实的优势,从而有利于弱势粒的灌浆充实.从总体上讲,10～50 mg/L ALA对弱势粒(第Ⅲ粒位)粒重的影响程度大于强势粒(第Ⅰ和第Ⅱ粒位),其中30 mg/L ALA促进籽粒增重的效果最明显.

Dynamic Simulation and Characteristic Analysis of the Effects of ALA on Grain Filling of Winter Wheat in Various Grain Positions

Using Bainong AK58 as experiment material, a field experiment was conducted to examine the effect of different concentrations of 5-Aminolevulinic acid （ALA） （10 mg/L, 30 mg/L, 50 mg/L） applied at initial heading stage on grain filling of winter wheat in Various Grain Positions. The resulgs were as follows： The data of grain weights were fitted to the nonlinear cumulative Richards growth model as a function of days after anthesis. Grain growth analysis based on Richards equation indicated that compared with the control, the final grain weights of the first and third grain in 10～50 mg/L ALA treatment were increased by 1.3～2.4 g/1000 grains, 3.4～4.7 g/1000 grains and there was no significant increase for the second grain. Applying 10--50 mg/L ALA enhanced the average and maximum grain filling rates, prolonged the active grain filling durations, and shortened the time reaching the maximum grain filling rates in various grain positions. By applying 10～50 mg/L ALA the grain filling rates in the three grain positions （the first, second and third grain） were increased while durations were short.ened during the early grain filling phase, and both the rates and durations of grain filling were increased in the three grain positions during the middle phases, however the grain filling durations increased while rates decreased in superior grains （the first and second grains） and both the rates and durations of grain filling were increased in inferior grains （the third grain） during the late phase. The results indicated that applying 10～50 mg/L ALA promoted the initial grain filling process of various grain positions and increased their grain filling rate during the early and middle phases, and relaxed the asynchronous process of superior and inferior grains, declined the suppression of the former on the latter during the late phases. In conclusion, the magnitude of the effects of ALA on grain filling was quite greater for inferior grains （the third grain） than that for superior grains （the first and second grains）. The highest grain yield was obtained when ALA was applied at level of 30 mg/L.