Salinity Tolerance of Guar or Cluster Bean (Cyamopsis tetragonoloba L.) Genotypes.

Salinity and water scarcity are the major challenges faced by many arid and semi-arid regions of the world. Developing appropriate crops/cultivars is critical for ensuring long-term viability of agriculture in these stressed regions. This greenhouse study evaluated salinity tolerance of 25 cluster bean or guar (Cyamopsis tetragonoloba L.) genotypes by determining seedling emergence, shoot length, root length, above and below ground biomass, major cation and anions in plant tissue after 15 days of sowing. Treatments included three salinity levels of 3.0 dS m-1, 6.0 dS m-1, 9.0 dS m-1 and the control (Indus River water with a salinity of 0.6 dS m-1). Genotypes were categorized as tolerant (> 60%) and sensitive (<60%) based on the seedling emergence at a threshold salinity level of 9 dS m-1. Results indicated four (S-5881, S-5932, S-5981, S-6067) were tolerant and the remaining 21 were considered as salt sensitive genotypes, respectively. Seedling emergence, shoot and root length, shoot and root dry matter decreased significantly with increasing salinity of the irrigation water. Results of our study indicated that guar, an important industrial crop, has a great potential for regions facing salinity.