麦稻田水竹叶发生特点及其化学防除技术研究

Study on the occurrence characteristics and chemical control techniques of Murdannia triquetra in wheat and paddy fields

对麦稻田水竹叶发生特点及其化学防除技术进行了研究。结果表明:麦田中的水竹叶种子3月上中旬开始萌发,4月中旬出苗达到高峰,5月中下旬麦子收割后匍匐茎留于田间,并随耕翻进入稻田开始无性繁殖;水稻种植3周后水竹叶进入生长旺期,并产生大量的一二级分枝,7月下旬和9月上中旬分别出现2个发生高峰;水竹叶9月上旬始花,下旬结实,10月上旬种子成熟,并自然开裂脱落田间,完成其整个生活史,全生育期约210 d。水竹叶的防除应坚持麦田防除压基数为主、稻田补除为辅的原则。(1)麦子生长期、水竹叶萌发前以喷雾法或毒土法使用苄嘧磺隆wP进行土壤处理,水竹叶出苗后2—4叶期以喷雾法使用氯氟吡氧乙酸EC或2甲·灭草松AS进行茎叶处理,(2)粳稻生长期、水竹叶2—3分枝期,以喷雾法使用氯氟吡氧乙酸EC或2甲4氯钠AS进行茎叶处理。上述药剂不仅除草效果好,药效表现快,而且对小麦和粳稻生长安全。

The occurrence characteristics and chemical control techniques of Murdannia triquetra were stud- ied in wheat and paddy fields. The results showed that the seeds of Murdannia triquetra in wheat fields began to germinate in mid-March, and the sprout reached the peak in mid-April. The creeping stems were left in the fie after wheat harvest in mid-to-late May, and began the asexual reproduction by ploughing into paddy field. Mur- dannia triquetra entered the growth period 3 weeks after planting flee, and generated a large amount of primary and secondary branches. The generation of branches reached two peaks respectively in late July and mid-Septem- ber. Murdannia triquetra bloomed in early September and seeded in late September. Murdannia triquetra comple- ted its whole life cycle after seeds matured in early October and then fall in the field after natural cracking. The whole growth period was about 210 days. Control of Murdannia triquetra should stick to rely mainly on wheat field control while paddy field control subsidiary. （ 1 ） Bensuffuron-methyl WP for preemergence treatment with spra- ying or toxic soil method were used in the growth period of wheat and before the germination of Murdarmia triquetra. Fluroxypyr EC or MCPA ＋ bentazon AS for postemergence treatment with spraying method were used in the 2----4 leaves stage of Murdannia triquetra. （2） Fluroxypyr EC or MCPA-Na AS for postemergenee treatment with spraying method were used in the japonica rice growing period or 2--3 branches stage of Murdannia triquetra. These herbicides not only had good weeding efficacy and fast pesticide effect, but also were safe to the growth of wheat and japonica rice.