A trial was conducted at the Gurabo Substation, Gurabo, Puerto Rico, to evaluate different methods (biological, manual and chemical) for controlling jointvetch (Aeachynomene sensitiva Sw.) and waterprimrose (Ludwigia erecta (L.) H, Hara) in rice. The sequential applications of either propanil [N-(3,4-dichlorophenyl) propanamide] or thiobencarb [S-(4- chlorophenyl) methyl diethylcarbamothioate] as an early postemergence, followed by a mixture of [(2,4-dlchlorophenoxy) acetic acld] and bentazon [3-(1-methylethyl)-(1H)-2,1,3-benzothiadiazin-4-(3H) one 2,2-dioxide] were found to be the two best treatments. Both treatments outyielded all others except the weeded check. However, no significant economic gain in terms of gross income and net return was evident for the aforementioned treatments. The sequential application of propanil followed by CollegoTM (a mycoherbicide) gave only fair weed control and produced a poor yield with low economic gain. Manual weeding produced the higher yield, but with the least net return due to the high cost of weeding.


Downloads Statistics

Download Full History