New sucker control chemical for tobacco cultivation in Japan
In the tobacco cultivation system in Japan, two contact type materials, i.e., decyl alcohol and pendimethalin, have been used as sucker control chemical. Butralin, which has already been used as a sucker control chemical in many foreign countries, was registered as the 3rd sucker control chemical in Japan. This paper reports the sucker control effect of butralin. The field test on burley tobacco was carried out in Morioka and Oyama using pendimethalin as control chemical in the 2002 crop season. An about 100% sucker control effect was observed both for butralin and for pendimethalin, and no phytotoxicity was observed in both of the chemicals. From these results, it was judged that butralin could be used practically for burley tobacco. The field test on flue cured tobacco was carried out in Kagoshima and Oyama using pendimethalin as a control chemical in the 2003 crop season. Butralin showed almost the same sucker control effect as pendimethalin, and no phytotoxicity was observed in both of the chemicals. From these results, it was judged that butralin could be used practically for flue cured tobacco. The registration of butralin has provided farmers with a wider choice of sucker control chemicals. Just as decyl alcohol and pendimethalin, butralin is a contact type sucker control chemical. Thus the spot spraying system using a particular nozzle is the only method usable for butralin. In order to maximize its sucker control effect, it is indispensable to use this chemical according to the GAP. It is very important to make farmers understand this fully.