双环磺草酮除草活性及对水稻的安全性研究

双环磺草酮是一种以对-羟苯基丙酮酸双氧化酶 (HPPD) 为作用靶标的双环辛烷类化学除草剂。为明确其在水稻田的应用技术，采用温室盆栽法测定了双环磺草酮的杀草谱、除草活性及对8个水稻品种的安全性。结果表明:在有效成分360 g/hm2剂量处理下，双环磺草酮对水稻田常见杂草稗草Echinochloa crusgalli、雨久花Monochoria korsakowii、异型莎草Cyperus difformis的地上部分鲜重抑制率均高于90%，对主要秋熟杂草稗草E. crusgalli、牛筋草Eleusine indica、雨久花M. korsakowii、千金子Euphorbia lathyris、田皂角Aeschynomene indica和异型莎草C. difformis的GR₅₀值为有效成分48~196 g/hm2，除田皂角外，除草活性均高于对照药剂硝磺草酮。双环磺草酮对8个水稻品种的安全性研究结果表明:在有效成分720 g/hm2剂量处理下，隆两优华占、皖垦糯1号、皖稻68和绿旱粳1号4个水稻品种对双环磺草酮耐药性较高，徽两优882、C两优608、皖稻119和Y两优1号4个水稻品种的株高和鲜重受到不同程度的抑制。双环磺草酮在隆两优华占、皖垦糯1号、皖稻68和绿旱粳1号4种水稻与异型莎草、稗草和雨久花3种杂草之间的选择性指数分别为3.66~4.37、4.50~5.37、3.36~4.01和3.29~3.93，明显高于对照药剂硝磺草酮。研究表明，双环磺草酮对多种秋熟杂草防效较好，且对供试的3个粳稻品种及5个籼稻品种中的隆两优华占安全。

Herbicidal activity evaluation of benzobicyclon and its safety to rice

Benzobicyclon, which targets the 4-hydroxyphenylpyruvate dioxygenase (HPPD), is a bicyclooctane herbicide. In order to explore its application in rice fields of China, the weed controlling spectrum, herbicidal activity, and safety of benzobicyclon to rice were investigated under greenhouse conditions. The results showed that the aboveground fresh weight reduction of common weeds in rice field, including Echinochloa crusgalli, Monochoria korsakowii and Cyperus difformis, were all above 90% at active ingredient of 360 g/hm². The GR₅₀ value of benzobicyclon against main autumn weeds were 48-196 g/hm². The biological activity of benzobicyclon was higher than that of mesotrione except in the case of Aeschynomene indica. The safety of 8 rice varieties to benzobicyclon was studied. At the rate of 720 g/hm², the tolerance of Longliangyouhuazhan, Wankennuo 1, Wandao 68 and Lvhanjing 1 to benzobicyclon were good. However, the plant height and fresh weight of Huiliangyou 882, C liangyou 608, Wandao 119 and Y liangyou 1 were inhibited in different degree. Selectivity index of benzobicyclon between Longliangyouhuazhan, Wankennuo 1, Wandao 68, Lvhanjing 1 and three weeds were 3.66-4.37, 4.50-5.37, 3.36-4.01 and 3.29-3.93, respectively, which was much higher than that of mesotrione. In conclusion, benzobicyclon had good herbicidal effect against autumn weeds, and it is safe to 3 japonica varieties mentioned above and Longliangyouhuazhan of 5 indica varieties.