Biological reclamation of salt affected soil through re-vegetation of Kochia indica

Soil salinity has become one of the major determinants of global crop productivity. Consequently, reclamation of these soils is the most urgent requirement for world food production and also for sustainable development. Sustainable use of saline wastelands could be possible through effective management strategies that including the biological reclamation techniques by using salt tolerant plants (i. e., shrubs, grasses and trees). The use of biological means to reclaim salt affected soils of unproductive agricultural lands may be a viable option. To achieve the aforementioned objectives, two pot experiment were carried out in the soil salinity laboratory, Alexandria, Egypt, to study the mutual influence of soil salinity (4 initial soil salinity levels referred as S1, S2, S3 and S4 in addition to the control) on growth, some cations content, and biomass production of Kochia indica plants which were grown in two different types of soils (alluvial and calcareous).Moderate levels of initial soil salinity was significantly increased most of the growth characters in both seasons. The S2 treatment in the first season and the S3 treatment gave the highest values for all the characters which were mentioned previously. The results indicate that there were improving in the growth characters of plants in the second season due to improving the initial soil salinity. On the other hand, leaf / stem ratio increased with increasing initial soil salinity. However the previous results were valid for both seasons. Increasing initial soil salinity significantly increased Na+ concentration in the plant tissues. On the other hand K^+, K^+/Na^+ ratio and Ca^2+ content insignificantly decreased with the same treatment as compared with control. No clear effects were recorded for Mg^2+. At harvest, the S3 treatment in both seasons gave the highest productivity. As for the effect of successive growing of Kochia indica on the soil quality, cations, anions (except for HCO^- 3), SAR, and electrical conductivity E.C., dS/m decreased in the soil analysis by the end of the first season and reached its lowest values by the end of the second season, this may be due to the leaching and to the accumulation of salts by Kochia indica as a halophyte plant which is capable of accumulating salts into their leaves vacuoles. Soil types significantly affected by most of the studied characters at vegetative stage and at harvest too.