Effects of salt stress on growth, nodulation, and nitrogen and carbon fixation of ten genetically diverse lines of chickpea (Cicer arietinum L.)

Abstract

Salinity is one of the major environmental constraints affecting agriculture in major regions of the world. It is known to depress greatly the growth and symbiotic performance of nodulated legumes. In the present study conducted over 2 rabi (dry) seasons, 2000–01 and 2001–02, 10 genetically diverse chickpea lines were compared for salt tolerance in terms of growth, nodulation, moisture content, and nodule nitrogen and carbon fixation. Chickpea lines were raised in an open-air chamber in soil supplied with 0, 50, 75, and 100 mm NaCl. The shoot, root, and the single-plant weight declined with increasing level of salt. Chickpea lines BG-1075 (desi type) and BGD-70 (Kabuli type) showed better plant growth than the former 2 lines but were poorer in nodulation under salt stress. An almost identical pattern of salt response was observed for nodule number, weight per nodule, nitrogen, and carbon fixation among the chickpea lines. No distinct relationship was found among root/shoot ratio, plant moisture content, and salt tolerance response of the chickpea. However, nodulation capacity (number and mass) under salt stress was related to salt tolerance response of chickpea lines. This trait could be used for improvement of salt tolerance of this legume species in order to increase its productivity and stability in saline soils.