北疆植棉区滴灌量对化学打顶棉花植株农艺性状及产量的影响

Effect of Drip Irrigation Amount on the Agronomic Traits and Yield of Cotton Grown with a Chemical Topping in Northern Xinjiang, China

【目的】探索滴灌量变化对化学打顶棉花农艺性状及产量的影响,为棉花化学打顶技术的应用提供依据。【方法】2016年,田间自然条件下,以人工打顶作为对照,选用氟节胺复配型和缩节胺复配型两种打顶剂,分别设3种不同滴灌量,通过测定不同处理棉花农艺性状、机采前脱叶效果及产量变化,分析不同滴灌量条件下棉花化学打顶株型变化及产量效应。【结果】打顶处理与滴灌量处理对棉花株高及果枝长有显著的互作效应,其中化学打顶×中滴灌量组合较化学打顶×高滴灌量组合株高平均降低6%,果枝长平均变短12%,产量差异不大;而较化学打顶×低滴灌量组合株高增加13%,果枝长平均增加14%,籽棉产量却增加7%。化学打顶与人工打顶之间脱叶率及杂叶率无显著差异,而较低的滴灌量可以加快化学打顶棉花的脱叶进程。与人工打顶相比,化学打顶虽显著降低了上部果枝铃重,但对衣分及产量无显著影响。【结论】喷施打顶剂后的2次灌水控制在中滴灌量(32 m3·667 m^(-2)),不仅可以调节化学打顶棉花的株型和脱叶进程,还可以在不降低籽棉产量的同时减少滴灌量,生产上具有一定的应用价值。

[Objective] This research aimed to clarify the optimization of EMS concentration and treat duration on mutation of Gossypium arboretum L. and create excellent mutants library. [Method] Seeds of Gossypium arboreum line Shixiya1 were immersed in EMS solutions with volume fraction ranging from 0.4% to 1.5% by 4-8 h. Then, the seed germination index and seedling growth were analyzed and the morphological character of M1, M2, and M3 generation were identified. [Result] The treatment with 0.6% EMS for 8 h was appropriate for Shixiya 1 mutagenesis. Under this treatment conditions, the seed germination index and the germination rate were 18.84 and 51%, respectively. To obtain abundant mutants, approximated 23 000 seeds of Shixiya 1were treated with 0.6% EMS for 8 h. 5559 mutants were screened out from M1 generation, 825 and 57 from M2 and M3, respectively. The mutation frequency of Shixiya 1 was 48.37%. The mutation frequency of leaf type variants, plant type variants were the highest in M2, which were 8.0% and 5.9%, respectively.The inheritable frequency of mutant characters from M2 generation to M3 generation was 31.30%, and the mutant frequency of M3 generation was 18.26%. [Conclusion]This study have established the EMS mutagenesis system of Gossypium arboreum line Shixiya 1, and created 36 steadily inherited mutants. The mutant library we constructed will be a very useful genetic resource for functional genomics and genetic improvement in cotton.