密度对春小麦籽粒灌浆特性的影响

在河西绿洲生态条件下,以旱地春小麦‘西旱1号’为材料,在密度为18.17~520.83基本苗.m-2范围内预设12个密度处理,研究了密度对籽粒灌浆的影响.结果表明:密度处理产量的变幅为2 508.08~5 276.46kg.hm-2,千粒质量的变幅为42.20~53.82 g.各密度处理的灌浆过程可用Logistic方程模拟.渐增期、快增期、缓增期对籽粒的贡献率分别为18.08%~27.10%、55.00%~67.68%、13.10%~34.99%.随着密度的增大,灌浆持续期(T)缩短,平均灌浆速率(R)降低,其中以18.17基本苗.m-2的R最高,401.50基本苗.m-2最低,但各密度处理最大灌浆速率出现的时间基本一致.千粒质量与T(0.912**)、R(0.752**)、最大灌浆速率出现的时间(TRmax)(0.910**)、最大灌浆速率(Rmax)(0.893**)、渐增期灌浆持续时间(T1)(0.701**)、快增期灌浆持续时间(T2)(0.730**)、缓增期灌浆持续时间(T3)(0.866**)、渐增期灌浆速率(R1)(0.751**)和快增期灌浆速率(R2)(0.804**)均呈极显著正相关,与缓增期灌浆速率(R3)(-0.163)相关不显著.T对粒质量的影响大于R的影响,但R与Rmax(0.782**)、TRmax(0.739**)呈极显著正相关.

Effect of density on grain filling characteristics of spring wheat

The effect of density on grain filling characteristics of spring wheat cultivar 'Xihan No.1' was studied in the Hexi oasis ecological condition,north-west of China.Twelve planting densities were set from 18.17 to 520.84 seedlings per square meter.The results showed as follows: grain yield varied range was 2508.08~5276.46 kg·hm-2,while thousand kernel weight(TGW)varied range was 42.20~53.82 g.The process of grain filling under each treatment could be well described by Logistic equation.The variable amplitude of contribution rate of gradual growth period,fast growth period,slow growth period to the grain was 18.08~27.10 %,55.00~67.68 % and 13.10~34.99 %,respectively.With the increasing of planting density,the grain filling duration(T) was shortened,the average grain filling rate(R) was reduced,the grain filling rate reached to the highest and lowest under the treatment of 18.17 seedlings per square meter and 401.50 seedlings per square meter respectively,the appearance time of maximum grain filling rate(TR_max) of each treatment were similar.The correlation analysis showed that TGW of spring wheat was positive correlated with grain filling duration(0.912**),average grain filling rate(0.752**),maximum grain filling rate (R_max)(0.893**),appearance time of maximum grain filling rate(TR_max)(0.910**),grain filling duration in gradual growth period(T_1)(0.701**),grain filling duration in fast growth period(T_2)(0.730**),grain filling duration in slow growth period(T_3)(0.866**),grain filling rate in gradual growth period(R_1)(0.751**),and grain filling rate in fast growth period(R_2)(0.804**) at 0.01 significant level,but it was not significantly correlated with the grain filling rate in slow growth period(R_3)(0.163).Effect of T on grain weight was greater than R,but R was significantly correlated with R_max(0.782**) and TR_max(0.739**).