Growth and chemical composition of dry beans as affected by soil salinity and N fertilization

Summary The effects of three levels of N (0, 50 and 100 ppm) and four salinity regimes (0.5, 1.5, 2.5 and 3.5 mmhos/cm) on the growth and mineral composition of dry beans (Phaseolus vulgaris L.) were investigated in a greenhouse experiment. Bean plants treated with N produced more dry weight and contained higher N than the untreated check. Growth and N uptake by bean plants generally decreased with increasing irrigation water salinity at all N levels. High salinity caused severe burning of the margins of older leaves and stunting of growth. At the low salinity levels (0.5 and 1.5 mmhos/cm), N additions had no effect on growth; however, the suppressing effects of higher salinity were alleviated somewhat with N fertilization.The concentration and uptake of Cl and Na increased with increasing salinity; probably the relatively high accumulations of Cl and Na were responsible for growth reductions at high salinity.