Yields of upland and lowland taro at varying plant densities

Abstract

A study was conducted to determine the effects of plant density on the yields and yield components of taro under upland and lowland culture in Hawaii. In both systems, total yields decreased as plant density decreased. Corm weight, cormel weight, and number of cormels per hill were inversely related to the number of plants per hectare. Regression analysis revealed that the yields and yield components of both upland and lowland taro follow an asymptotic relationship with plant density, which is typical of yields derived from vegetative part of the plant. Lowland taro had higher yields than upland taro, and the main factors that contributed to the higher yields of lowland taro were the higher number and greater weight of cormels produced at all plant densities. Lowland taro corm yields were higher than upland taro except in the lowest plant density where upland taro corm yield was higher both on a per hill basis and on total weight per hectare. There were no significant effects of plant density on the total yields of cormels in the upland although the number and weight of cormels per hill were significantly affected by plant density. There is a negative relationship between plant density and the number and weight of cormels per hill. Maximum yields of both upland and lowland taro were obtained at 10.9 plants per sq. m. This population density resulted from a plant spacing of approximately 30 cm × 30 cm.