水稻化感品种结合使用除草剂及深水层管理对稻田杂草的抑制作用

选用具有化感特性的水稻品系华抗草78和长江流域地区主栽的扬稻6号,通过田间试验研究水稻化感作用结合苄嘧磺隆使用及水层管理对水稻田杂草的抑制作用,旨在降低水稻田化学除草剂使用量,探索水稻生产中杂草治理的新途径.结果表明,水稻化感作用结合深水层可有效抑制稗草的萌发和生长,同时水稻移栽后6 d使用苄嘧磺隆(30 g/hm~2)单剂处理,明显地抑制了异型莎草和陌上菜的萌发数量和生物量积累;水稻移栽后50 d,华抗草78和扬稻6号对稗草的干重防效分别为89.16%和81.86%,对异型莎草的干重防效分别为83.56%和84.93%,对陌上菜十重防效分别为95.22%和88.04%,对这3种杂草的总干重防效分别为87.68%和82.69%:10cm深水层及施用苄嘧磺隆单剂条件下2个水稻品种(系)的产量比5 cm水层、不施化学除草剂的处理分别增产40.33%和21.36%.水稻化感品种对稗草等的抑制作用、水稻自身的竞争作用、10 cm深水层及苄嘧磺隆单剂这4种因素的综合效应不仅具有良好的控草效果,增产显著,而且明显降低了除草剂的使用量.

Integrated Inhibition of Allelopathic Rice, Herbicide Application and Deep Water Level on Weeds in Paddy Field

Field experiments were conducted to examine integrated inhibition of allelopathic rice(Huakangcao 78).bensulfuron methyl application and water nmnagement on weeds in paddy field,with the purposes of attempting to reduce the dosage of herbicide applied in rice field and exploring new ways of weed management in rice production.The results showed that allelopathic rice could inhibit the germination and growth of barnyardgrassEchinochloa crusgalli(L.)Beauv ] effec-tively,and bensulfuron methyl(30 g/hm~2)applied 6 d after rice transplanting could significantly reduce the plant nnm-bets and biomass accumulation of difformed galingale(Cyperus difformis L.)and procumbent falsepimperneLindernia procumbens(Krock.)Philcox].The control efficiency of Huakangcao 78 and Yangdao 6 were 89.16% and 81.86% on bamyardgrass dry weight respectively 50 d after the rice transplanting,83.56% and 84.93% on difformed galingale dry weight,95.22%and 88.04% on procumbent falsepim-peme dry weight.As a whole,the total dry weight control efficiency were 87.68% and 82.69% on above weeds corre-spondingly.Moreover,the grain yield of Huakangcao 78 and Yangdao 6 under the condition of 10 cm deptll water and her-bicide application increased 40.33% and 21.36% comparing those under the treatment of 5 cm depth water and no herbicide application respectively. Synergistic actions of allelochemi-eals, rice competitiveness, 10 cm depth water and herbicide had the advantages of better control effect on the weeds, highergrain yield of rice and distinct lower herbicide dosage.