冬小麦地下滴灌氟乐灵注入制度对根系生长及作物产量影响的试验研究

通过田问试验,研究了地下滴灌施加氟乐灵对滴头根系入侵堵塞的控制效应及其对冬小麦产量、品质和根系分布的影响.试验选取施药日期和施药浓度2因素.施药日期取返青末期和抽穗初期2个水平,施药浓度取0,50,75mg/1和150mg/1共4个水平.冬小麦收获后,采用土钻法在滴头附近沿垂直方向分层取样,测定各土层的根长密度和氟乐灵含量,并统计各小区的产量.同时,在每个小区内随机抽取25个滴头,观测滴头流道内是否有根系残留.从而判断滴头是否发生根系入侵堵塞.试验结果表明,施药可以有效地削减滴头附近区域的根密度,从而减小根系入侵堵塞的发生.在对照小区内(0mg/1)抽取的25个滴头中有4个出现了根系堵塞现象(堵塞率16%),而在施药的各个处理中均未发现根系堵塞的滴头(堵塞率0).施药浓度对根系分布及作物的产量、品质均无显著影响.而施药日期对冬小麦根系的垂直分布影响较为显著,晚期施药导致滴头埋设深度处小范围内(15～30cm深度)的根系有所减少,而早期施药则使滴头下方较大区域内(15～40cm深度)的根长密度显著减小.

Effect of treflan injection on root growth and yield of winter wheat under subsurface drip irrigation

Field experiment was conducted to investigate the effects of treflan injection on dripper clogging and root distribution, yield and quality of winter wheat. Two treflan injection dates and four injection concentrations were designed as the experimental conditions. At harvest, root length density and treflan concentration at different soil layer were evaluated using soil auger method. The flow passages in 25 drippers randomly selected were carefully observed to check whether the root residue was existed to estimate the root clogging situation. The results show that treflan injection can reduce the root length density in the vicinity of dripper resulted in reduction of potential of root clogging. Four drippers with root intrusion problem were found for those without treflan injection but no intrusion problem happened for the drippers with application of treflan. Trefian concentration had insignificant effect on winter wheat root distribution, yield and quality. However, injection date influence the root vertical distribution significantly. Injection of treflan in latter growing season will influence the root distribution in close vicinity of the drippers only.