Phenotypic Variations in Plant Height and Root Traits under Moisture Stress in Maize Varieties from Hawassa, Ethiopia

Aim: Maize (Zea mays L.) is the third most important food grain for humankind after rice and wheat. Therefore, the aim of this study is to evaluate the phenotypic variations in eight maize varieties under moisture stress.

Materials and Methods: All the varieties were grown with 3 replications in 75 cm deep polyethylene bags containing soil from study area for 30 days under four moisture stress conditions i.e. 25%, 50%, 75% and 100% of Field Capacity (FC) in green house.

Results: Significant variation existed in plant height, primary root length, root dry weight and shoot dry weight under different moisture conditions. The plant height and primary root length of maize seedlings under drought condition decreased in all tested maize varieties from 100% to 25% of moisture content. The average primary root length ranged from 27.5 to 88 cm. Melkassa 02 variety showed highest primary root length whereas, lowest mean root length was observed in Hora variety. Root and shoot dry weight also showed significant differences among eight maize varieties at different moisture levels. Each variety was also evaluated for ratio of root to shoot dry weight at different moisture levels in comparison to control. At 25% of FC, Pioneer variety recorded highest value for root to shoot ratio of dry weight with 2.4 fold increased followed by Hora, BH140, and Melkassa 02. Melkassa 04 reported least value for root to shoot ratio.

Conclusion: Results of our study has major implication for future breeding in maize. Under different condition of moisture stress, variations in maize morphological characteristics were observed. Thus more sampling should be done in future where maize is grown under adequate drought tolerance strategy.