Effect of Different Planting Dates on Yield Components and Yield in Sweet Potato

Abstract

The objective of this study was to evaluate the effects of different planting dates on yield components and yield of four sweet potato varieties under cultivation conditions at Ubon Ratchathani University. A factorial experimental design in a Completely Randomized Design (Factorial in CRD) was planned with two factors. Factor 1 comprised four sweet potato species: Beni Haruka, Taneka Murasaki, Orange Okinawa Kugami Imo, and Annou Imo. Factor 2 was the planting date, on April 16, 2021 (early rainy season), July 14, 2021 (mid-rainy season), and November 22, 2021 (dry season). The experiment was repeated four times, and data were recorded. Information on yield components and yield of sweet potatoes at harvest day included; Number of tubers, Tuber length, Tuber width, Fresh weight of tubers, Dry weight of tubers, Total dry weight, Harvest Index. It was observed that different sweet potato cultivars and planting dates significantly affected yield components and overall production. All sweet potato varieties planted at the early-rainy season and dry season produced between 4-8 tubers, with a fresh tuber weight of 400-600 grams per pot. However, when planted during the mid-rainy season, they failed to produce a significant yield. Interestingly, the harvest index of sweet potato varieties across different planting dates did not affect the yield.