Effect of water and salt stress on soil moisture status under nursery conditions

Abstract

Soil is a natural body developed through pedogenic process, consisting of all necessary mineral and organic constituents who are require for plant growth and productivity. Therefore, any changes in the soil properties directly affect the plant growth status. In the present study, effect of artificially created abiotic stresses like drought, water logging, salinity, combined salinity + drought and salinity + water logging on the soil moisture of selected tropical forest tree species seedlings viz: Tectona grandis, Gmelina arborea, Dalbergia latifolia and Pongamia pinnata have been seen by performing pot culture experiment in factorial CRBD manner in TFRI nursery for one year duration. Transparent polythene bags were used filled with soil, sand and farm yard manure (FYM) in 2:1:1 ratio, keeping the weight of polybags fixed at 2 kg. The amount of water equal to the field capacity was given to each polybags. The moderate and severe drought conditions were created with the help of cumulative pan evaporation and permanent wilting point values. The artificial moderate and severe water logging conditions were created by perforating 8 periphery holes in the polybags below 6 cm and 3 cm from surface. 4dS/m, 8dS/m and 12dS/m sodium chloride salt dissolved water provided regularly for maintaining the salinity conditions. The salt doses combined with the illustrated drought and water logging way of treatments for generating combined salinity and drought & combined salinity and water logging conditions. The soil was analyses for general physicochemical characteristics so as to standardize the non-difference in the soil used along with the soil moisture by following gravimetric method. The soil moisture was measured initially on the start of experiment (August 2015) and then at six months intervals (February 2016 and August 2016). The data statistically analyses by using ANOVA table and CD values stated that there was the significant difference in the soil moisture readings of selected tree species. The maximum soil moisture was found in the severe waterlogged treatment, followed by moderate waterlogged, control and moderate drought and minimum in severe drought treatment irrespective of salt concentrations. Higher dose of salt concentration retains more moisture in the soil. The soil moisture holding capacity of different species remains unaffected under selected abiotic stresses.