除草剂对强筋小麦产量及生理特性的影响

在盆栽和大田条件下,研究4种除草剂对2个强筋小麦品种(“临优145”和“临汾138”)产量及生理特性的影响.结果表明,在推荐用量下,除草剂对成穗数、穗粒数和穗长的影响较小,对株高、千粒重、旗叶叶绿素相对含量(SPAD值)、净光合速率及灌浆进程影响较大.2,4-D丁酯使旗叶SPAD值、净光合速率一直较低,千粒重降低;“巨星”在灌浆前期使旗叶SPAD值、净光合速率保持较高,灌浆中后期快速下降,并使灌浆持续时间相对缩短,千粒重最低,较对照分别低2.40g和0.84g;而“世玛”使灌浆前中期SPAD值和净光合速率较低,但下降相对缓慢,使灌浆持续时间分别延长3.48d和1.86d,“库”容增加,千粒重分别提高1.18g和1.05g,同时具有一定的降低株高作用;“骠马”虽使灌浆持续时间延长,但影响相对较小.除草剂对籽粒生长模型参数的影响,品种间存在一定差异,除草剂对“临优145”初始生长势、快增期和缓增期持续时间、快增期和缓增期平均灌浆速率影响较大,而对“临汾138”的这些指标以及总灌浆持续时间影响较大.分析旗叶光合特性、灌浆进程、千粒重及产量间的相关性,表明除草剂主要是通过旗叶生理和灌浆进程来影响千粒重和产量.图1表7参19

Effects of Herbicides on Grain Yield and Physiological Characteristics of Strong Gluten Wheat

Effects of four herbicides on yield and physiological characteristics of two strong gluten wheat varieties ("Linyou145" and "Linfen138") were studied in pot and field. Results showed that the of herbicides on spikes, kernels per spike and spike length were less than those on plant heights, 1 000-kernel weight, flag leaf chlorophyll, Pn, and grain filling. After using 2.4-D butyl, flag leaf SPAD value and Pn were low during filling stage, and 1 000-kernel weight was reduced. After using tribenuron-methyl, SPAD value and Pn were high in early filling stage, and declined in middle and late stages, which made the whole filling period shortened, 1 000-kernel weights of the two varieties the lowest, 2.40 g and 0.84 g lower than that of control, respectively. After using "Sigma", SPAD value and Pn were low in early and middle filling stages, and reduced slowly in late stage. The filling periods (T) of the two varieties were prolonged for 3.48 d and 1.86 d, their "1 000"-kernel weights were increased by 1.18 g and 1.05 g, and plant height was reduced. The filling period was prolonged little after using Fenoxaprop-P-ethyl. There were different effects of herbicides on grain filling traits of the two varieties. As for "Linyou145", the effects on initial growth capacity (C0), filling period of fast and slowly increasing stages (T2, T3), average filling rate of fast and slowly increasing stages (R2, R3) were higher than other parameters. For "Linfen138", the effects on total filling continual period (T), C0, T2 and T3 were higher than others. Analysis of correlativity among flag leaf photosynthetic characteristics, grain fill, 1 000-kernel weight and yield showed that herbicides affected the 1 000-kernel weight and yield of strong gluten wheat, mainly through flag physiologic characteristic and grain filling. Fig 1, Tab 7, Ref 19