Response of Coffee Varieties to Contrasting Soil Moisture Regimes at Seedling Stage

Abstract

Drought stress has become a devastating and chronic factor affecting growth, yield and quality of arabica coffee (Coffea arabica L). The study was initiated to investigate root traits of coffee varieties associated with drought tolerance. The experiment was carried out in plastic shelter with a factorial randomized complete block design in three replications. A total of 20 treatments combinations viz; ten arabica coffee varieties (five drought tolerant and five sensitive) with two water regimes (well-watered and water stressed) were used. Various root traits were measured and subjected to analysis of variance. It was observed that except for tap root diameter, the remaining root traits of varieties were significantly (p < 0.05) affected by soil moisture regimes and recovery periods. Compared to well-watered regime, all the measured root traits were significantly increased under soil moisture stress. The highest taproot length, taproot diameter and root length density were obtained from 74110, while the highest specific root length was recorded from Bultum under both soil moisture stress and recovery periods. At similar conditions variety Angefa had shown the highest root volume, root angle, root to shoot ratio and root mass ratio. However, varieties Mokah, Menasibu and MCH2 were least performed. Overall, the study investigated variability of coffee varieties in root traits and their mechanisms for drought stress adaptation, and declared further exploration using more genotypes.