Root measurements for different cassava genotypes planted under three water management levels

Abstract A study on the growth of roots could improve the efficiency of varietal selection. This study aims to investigate the performance on root and yield of eight cassava ( Manihot esculenta Crantz) genotypes grown under three different water management levels during the early growth phase. A strip–plot design with four replications was used. Three levels of irrigation during 30–180 days after planting (DAP) were factor A (W1 = 100%, W2 = 60%, and W3 = 20% of the crop water requirement), whereas the eight cassava genotypes were factor B. The cassava genotypes were grown in October 2019 and October 2020. The data were recorded for soil physical and chemical properties prior to planting, meteorological data, and crop data. The results from both years indicated that the W1 level produced higher root length, root volume, root surface area, chlorophyll fluorescence, and storage root dry weight than the W2 and W3 levels at 180 DAP. The genotype CMR38–125–77, grown under W1 during the early growth phase, exhibited greater root length, root volume, root surface area, and chlorophyll fluorescence, total crop biomass (excluding roots), and storage root yield compared to the other genotypes at 180 and 330 DAP. Under water‐limited conditions, the genotypes Rayong 11 and Rayong 9 had good performance for root length, root volume, and root surface area at 180 and 330 DAP. Measurements of root length, root volume, and root surface area based on the auger method could identify a superior genotype in terms of cassava biomass.