Study on Safe Dosage of Imazethapyr for an Imazethapyr Resistant Millet Variety and Its Effect on Weed Control

[Objective] This study aimed to investigate the safe dosage of imazethapyr for an imazethapyr resistant millet variety and its effect on weed control. [Method] The Imazethapyr resistant millet ＂M1508＂ was used as the experimental material and the experiment was arranged in a split plot design with two factors： herbicide application time and herbicide dosage. Application time was taken as the main plot with six treatments： A1 （preemergence treatment）, A2 （postemergence treatment on the 3rd d）, A3 （postemergence treatment on the 6th d）, A4 （postemergence treatment on the 9th d）, A5 （postemergence treatment on the 12th d）, A6 （postemergence treatment on the 15th d）; spraying dosage（B） with nine treatments： B1 （0 ml/hm2 , taking water as control）, B2 （750 ml/hm2 ）, B3 （1 125 ml/hm2 ）, B4 （1 500 ml/hm2 ）, B5 （2 250 ml/hm2 ）, B6 （3 000 ml/hm2 ）, B7 （4 500 ml/hm2 ）, B8 （6 000 ml/hm2）, B9 （7 500 ml/hm2 ）; water was added at 675 kg/hm2 . [Result] Imazethapyr showed a good herbicidal effect, and the imazethapyr resistant new variety M1508 also had a high drug resistance; the dosage range of 750 -7 500 ml/hm2 was safe for millet; considering the weed control efficacy, the yield and weeding cost comprehensively, postemergence treatment on the 6th day at 1 500 -2 250 ml/hm2 was the best for herbicide application. [Conclusion] Matched chemical weeding techniques to imazethapyr resistant millet varieties were preliminarily identified, and the efficacy of imazethapyr on weed control and its security on millet were investigated, providing references for the application and promotion of imazethapyr resistant millet varieties.

施肥量和留苗密度对谷子杂交种张杂谷8号产量及主要农艺性状的影响

为解决部分谷子杂交种"库"、"源"失调,生育后期易脱肥,产量潜力得不到充分发挥的问题,以张杂谷8号为试验材料,采用裂区试验设计,其中,主处理为施肥量,设6个水平(拔节期沟施KCl150 kg/hm2+尿素75 kg/hm2,抽穗前沟施尿素150 kg/hm2;拔节期沟施KCl 150 kg/hm2+尿素75 kg/hm2,抽穗前沟施尿素225 kg/hm2;拔节期沟施KCl 150 kg/hm2+尿素75 kg/hm2,抽穗前沟施尿素300 kg/hm2;拔节期沟施KCl 225 kg/hm2+尿素150 kg/hm2,抽穗前沟施尿素150 kg/hm2;拔节期沟施KCl 225 kg/hm2+尿素150 kg/hm2,抽穗前沟施尿素225 kg/hm2;拔节期沟施KCl 225 kg/hm2+尿素150 kg/hm2,抽穗前沟施尿素300 kg/hm2);副处理为留苗密度,设5个水平(22.50万株/hm2、26.25万株/hm2、30.00万株/hm2、33.75万株/hm2、37.50万株/hm2)。研究不同施肥量与留苗密度对张杂谷8号主要农艺性状和产量的影响,旨为建立谷子杂交种夏播高产栽培技术体系奠定基础。结果表明:施肥量对穗长和穗直径有显著影响,对产量有极显著影响,对株高和单位面积穗数影响不大;留苗密度对穗长、穗直径、单位面积穗数和产量有极显著影响,对株高影响不大。在相同密度条件下,随着施肥量的增加,谷子穗长、穗直径和产量增加;在相同施肥量条件下,随着留苗密度的增加,穗长和穗直径减小,单位面积穗数和产量增加,其中密度在30.00万～37.50万株/hm2范围内对产量影响不显著。综合施肥和密度互作试验产量结果,认为在冀中南夏播最利于发挥张杂谷8号产量潜力的栽培方式为:在30.00万～37.50万株/hm2留苗密度下,拔节期施KCl225 kg/hm2+尿素150 kg/hm2、抽穗前施尿素225 kg/hm2。

不同剂量40%乙烯利对谷子催熟增产效应的研究

以河北省主推谷子品种冀谷31为研究对象,设置5个不同的40%乙烯利剂量梯度(1 200、1 500、1 800、2 250和3 000 mL/hm2),在乳熟期喷施,分析了不同剂量40%乙烯利对谷子催熟和增产效果的影响。结果表明:40%乙烯利对谷子具有催熟和增产作用,随着喷施剂量的增大,单穗重、穗粒重、出谷率和产量均大致呈抛物线型的变化趋势,谷草含水量和叶绿素含量均大致呈直线型下降的变化趋势。40%乙烯利用于谷子催熟增产的最适宜剂量为2 250 mL/hm2,不仅对谷子叶片失绿和植株失水的催熟效果较好,且产量最高。本研究为乙烯利应用于配合谷子联合收割机收获奠定了理论基础。