EVALUATION OF HERBICIDE SPRAY DATES AGAINST NOXIOUS WEEDS OF SUGARCANE (Saccharum officinarum L.) UNDER IRRIGATION CONDITION AT WONJI SHOA SUGAR ESTATE, ETHIOPIA

Abstract

Weeds are one of the most damaging obstructions in sugarcane cultivation systems. The various cycles of sugarcane cultivation result in degrees of weed severity in which each species requires a different weed control method, the most popular of which is the pre-emergence herbicide method. The previously used pre-emergence herbicide application date in Wonji/Shoa sugar factory was applied mostly in the wide range of days within the standard (7-15 spray interval days). Due to this reason, some weed species develop resistance to pre-emergence herbicide application, some weed species become noxious and causes high cost of weed control. The efficacy of pre-emergence herbicide application dates in noxious weed control is presented herein, through an experiment conducted in a randomized complete block design (RCBD) with three replications from March, 2022 to January, 2023. The herbicide Ametryn + atrazine application was more efficient in early dates in zero and two dates after second irrigation in noxious percent weed control. Sugar yield and cane yield of hand weeded treatment had highly significant difference than unweeded treatment. However, pre-emergence herbicide sprayed treatments had no significant difference among different spray dates and hand weeded treatment, the unweeded treatment recorded lowest sugar yield and cane yield. From this finding we could conclude that, amethryn + atrazine can be applied to control the weeds at zero to two days after second irrigation of plant cane field as pre-emergence with comparative control advantage of manual hand weeding.