Screening of Common Bean (Phaseolus vulgaris L) Germplasm for Drought Stress

Abstract

Common bean is a species having high nutritional composition. Drought response in plants is complex phenomenon relating interactions between structure, functions and development of the plant. The Improvement of drought resistant for common bean has major objectives for many breeding programs. The growth of the plant, related to the parameter plays a vital role in the selection criteria for drought resistance. The increasing drought tolerance in commercial varieties is highly desirable. 20 varieties of common bean leaves were collected, it is subjected in vitro water stress with 10% polyethylene glycol 6000 (PEG 6000). The parameters are determined as a relative water content (RWC), seedling root length, leaf area, stomatal index, wax and proline. The result points out that these varieties responded differently during the drought stress. Tolerant and Susceptible comes under the varieties that are categorized which are based on RWC. The tolerant varieties maintain a high water content. Generally, the tolerant varieties are higher in seedling root length, leaf area, stomatal index, wax than the susceptible varieties. The proline accumulations are higher in susceptible varieties when compared to the tolerant varieties. A significant correlation was observed from the above parameters. The results are discussed with reference to the plant’s response during drought.

Keywords

• common bean
• drought
• proline
• relative water content
• stomatal index
• susceptible
• tolerant
• wax