Root yield and nutrient removal of four cassava cultivars planted in early rainy season of Northeastern Thailand: Crop experienced to drought at mid-growth stage

Abstract

The objectives of this study were to evaluate growth yield and nutrients removal of cassava cultivars planted in early rainy season under rainfed condition of Northeastern Thailand. Four cassava cultivars including Rayong-7, Rayong-11, Rayong-72 and Huaybong-80 were tested in randomized complete block design with four replications. The crops were planted in May and harvested after 345 days. Cassava plantation experienced to drought in December to March for four months. The results showed that the vigorous cultivar Rayong-7 gave highest of leaf dry weight, number of leaf retained per plant, number of new leaf produced per plant, number of storage root, storage root fresh weight per plant and storage root yield. Irrespective of nutrient removal; N, P and K removed ranges from 3.5-5.2,0.62-0.85 and 3.5-5.3 kg t-1 fresh root weight, respectively depending on cassava cultivar. The cultivar Rayong-7 removed maximum quantities of N, the cultivar Rayong-11 and Huaybong-80 removed the highest quantities of P and K, respectively. Regardless of nutrient removal at different plant parts; N, P and K removed maximum quantities in leaf, stem and storage root, respectively.