Effect Of Salt-nitrogen Sources Interactions On Growth, Root Respiration And Ion Balance Of Pea Seedlings

Salinity is one of non-biological factor of limiting agricultural productivity in arid and semi-arid regions, its area expanded gradually in recent years, so it is very significant that reasonable control and soil salinization amelioration for agricultural sustainable development. This was conducted for three different salt-tolerant pea species to investigate the effect of salt-nitrogen sour interactions on growth, ion balance and root respiration of pea seedlings. In order to explore the relationship between nitrogen and salt stress through comparative analysis results that effect of salinity on plant biomass, ionic balance, root respiration and rhizosphere pH under different nitrogen, it is explored that the contribution of legume root respiration to the soil pH, the main results were as followed:1. It is no significant differences of three different pea species biomass and root/shoot under salt-nitrogen sources interactions in the treatment and the control, the results showed that nitrogen alleviates the damge of salt stress on plants, the biomass was higher in nitrate condition than in ammonium condition. The water content of the plants were significantly reduced by 100mMNaCl than 50mMNaCl.2. The root length and root area of three different pea species was higher in nitrate condition than in ammonium condition, and exhibited a significant differences. The plant’s root length and root area were increased by 50 mMNaCl, the results showed that the scope of pea seedling roots absorb water and nutrients were increased by the concentration of salt stress, and and exhibited a significant differences between root length and root area in different pea species.3. The root respiration of three different pea species exhibited a reducing trend as salt concentration and incubation days increasing. The root respiration of Yinwan NO.1 was higher in ammonium condition than in nitrate condition, but the results of S5001-1 and Ha were opposite, and its root respiration were increased by 50 mMNaCl. The root respiration of Yinwan NO.1 was higher in the day than in the night, and exhibited a significant differences(P<0.05).4. Salt Stress disturbed the cation-anion balance in plants, the concentration of Na+ and Cl- exhibited a increasing trend as salt concentration increasing, but Na+ inhibits the uptake of K+、Ca2+、Mg2+ and SO42-, so the concentration of the K+、Ca2+、 Mg2+ and SO42- were reduced, and it is no significant differences of NO3- and H2PO4-.5. The rhizosphere of three different pea species were significantly acidified according to the ion balance formula, the results that three different pea species exhibited rhizosphere acidification. The chromogenic color results showed that three different pea species exhibited rhizosphere acidification under salt-ammonium sources interactions, and exhibited rhizosphere alkalization under salt-nitrate sources interactions, the alkalization degree was increasing as salt concentration increasing. The image treatment results showed that the acidification degree of the Ha was highest.