Effectiveness of compost and gypsum for amelioration of saline sodic soil in rice wheat cropping system

A lot of crop residues, kitchen wastes and tree leaves are wasted annually. These materials can be composted and used for improvement of soil health. The possibility of using compost in reclamation of salt affected soil was studied with the treatments i.e. control (no amendment), gypsum @ 100 % GR, compost 20 t ha-1, gypsum 50 @ % GR+ compost @ 20 t ha-1, gypsum 50 @ % GR+ compost @ 10 t ha-1, gypsum 25 @ % GR+ compost @ 20 t ha-1 and gypsum @ 25 % GR+ compost @ 10 t ha-1.in rice-wheat rotation at farmer field in Haveli Karimdad, Pindi Bhattian district Hafizabad, Punjab, Pakistan. The selected field was prepared and leveled. The design of the experiment was randomized complete block (RCBD) with four replications having the plot size of 8m x 6m. The prepared compost was applied and incorporated according to the treatments plan thirty days before transplanting of rice. Uniform cultural practices were applied to all the treatments. Rice-wheat crop rotation was used. The data for paddy yield of rice and wheat grain were recorded at maturity. The results showed that gypsum application @ 50% GR + compost @ 20 t ha-1 remained statistically at par with gypsum application @ 100% GR for producing biomass, paddy and wheat grain yield. However other treatments remained inferior but significantly better than control. The pHs and SAR were decreased significantly after harvesting of 2nd rice crop in two treatments i.e. gypsum application @ 100% GR and gypsum @ 50% GR+ compost @ 20 t ha-1. The ECe was reduced to less than 4 dS m-1 in all the treatments except control after 1st rice crop. The physical properties of soil such as bulk density, porosity and hydraulic conductivity were also improved with passage of time. Results of current study suggested that salt affected soil can rehabilitate to their original potential if gypsum is applied at the full rate (100% GR) alone or decrease its quantity 25 or 50% by combining it with compost at rate of 20 or 10 t ha-1.