The experiment was conducted on pea in sand culture and well nodulated plants were shifted to saline-alkaline conditions, A continued production of new nodules upto 35 days after shifting at a pH of 10, where the nodulation fails otherwise if the 10 pH exists from the time of sowing, clearly indicated that a complete inhibition of infection process leads to failure of nodulation at a pH of 10. Increasing pH (from 7 through 9 to 10) and salinity levels progressively reduced the production of new nodules and growth of the nodules. Nodules decay was evident at all salinity levels at a pH of 10 and at higher salinity levels of 9 and 12 mmhos/cm at 7 and 9 pH. Salinity and/or alkalinity reduced the production of pink pigment and enhanced greening, the effect being drastic at higher levels.
Total plant nitrogen and dry matter contents of the plants were reduced by increasing salinity and/or alkalinity. Growth of the newer leaves (leaf area) rather than their production was mainly reduced by saline-alkaline conditions.
