Impact of pesticide application in high frequency on stomatal number at local shallot in Palu Valley

Abstract

Small farmers typically produce shallot with a high frequency of pesticide application and its habit poses several ecological and environmental consequences. In this research, we evaluated the effect of pesticide application in different frequency (high, moderate and low) on shallot stomatal number and opening in Palu Valley, Central Sulawesi. By comparing in the low application, the moderate frequency with less than ten applications increased stomatal number about 1.9% and high rate with more than ten applications per two months of shallot plantation period augmented about 18.7%. While the length of stomatal opening increased about 18.2% with moderate and decreased about 32.6% with the high rate of application. Then, the width of the stomatal opening decreased about 0.6% and 17.5%, respectively. This data indicated that the application of pesticide, especially in high - frequency increase stomatal number and decrease stomatal opening area with potential for inhibiting shallot growth.