Effects of soil types on root traits and root anatomy of upland rice for varieties suitable selection for planting in central Thailand

Abstract

This research aimed to evaluate the effect of soil types on the root traits and root anatomy for selecting suitable upland rice varieties for planting in the central plains of Thailand. The experimental design was 2x4 factorial in completely randomize design (CRD) with two factors. The first factor was soil types, and the second factor was the upland rice varieties. Four upland rice varieties, namely Leum Pua, Sew Gliang, Jow Haw, and Jow Lisaw San-pah-tawng were selected for the root trait evaluation by using the basket method. All four rice varieties were grown in two experimental plots with conditions: Plot 1 the soil texture was sandy loam and Plot 2 the soil texture was clay loam. The results showed that at the tillering stage, rice varieties and soil texture had significant effects on the root traits. The upland rice varieties, grown in the sandy loam had the shallow root number (SRN) (19.92 roots), deep root number (DRN) (53.42 roots), and a total root number (TRN) (73.33 roots), and was higher than that grown in the clay loam. Jow Lisaw San-pah-tawng grown in sandy loam showed the highest SRN (29.00 roots), DRN (93.00 roots), and TRN (122.00 roots), and the interaction between rice varieties and soil texture highly significantly affected the SRN, DRN, and TRN. At the booting stage, rice varieties, soil texture, and the interaction of varieties and soil texture had a highly significant impact on the DRN and TRN. Upland rice varieties, grown in sandy loam, had a greater DRN and TRN than that grown in clay loam (65.15 and 86.85 roots, respectively). Jow Haw had the highest of DRN (82.50 roots), while Leum Pua had the greatest TRN (109.67 roots) followed by Jow Haw (100.75 roots).