Pongamia pinnata L. (Karanja) based agri-silviculture system under rainfed conditions of south-west Haryana

The present study was conducted to assess the the performance of Karanja based agri-silviculture system in rainfed conditions of south west Haryana. The results showed that the yield (grain and fodder) of different crops was not affected significantly by the Karanja trees during initial four years of plantation. The mean grain yield of crops viz. cowpea (9.47q/ha), cluster bean (9.13q/ha), dhaincha (8.57 q/ha) and mung bean (9.50q/ha) was slightly less in agri-silvicultue system as compared to sole cropping. Similar trend was also observed for fodderyield. Karanja growth (height and diameter) was more in agri-silviculture as compared to sole plantation. Maximum height of 300.00 cm and diameter of 89.20 mm was recorded when Karanja was intercropped with cowpea, whereas it was 281.20 cm (height) and 80.90 mm (diameter) in sole plantation. Agri-silviculture system also improved the organic carbon and available N, P, K as compared to sole cropping. The lower net returns from agri-silviculture system of Karanja + cowpea (Rs. 7178/ha), Karanja +clusterbean (Rs. 7725/ha), Karanja +dhaincha (Rs. 7254/ha) and Karanja + mung bean (Rs. 7100/ha) were mainly due to the fact that during initial years Karanja plantation required some cost without any economic return. It is evident from the results that the cost of establishment of plantation can be meet out through intercropping during the gestation period of Karanja plantation

Three decades of using of gypsum under sodic water irrigation in coarse textured soils

The aim of this study was to determine the long term use of sodic waters and gypsum on physico-chemical properties of coarse textured loamy sand soil. The study consisted of three natural occurring underground sodic waters and amendment gypsum in various cropping systems. The results demonstrated that sodic water irrigation significantly decreased infiltration rate (1.46 & 1.09 cm hr-1) and soil porosity (35.66 & 33.26 %) and increased soil strength (17.49 & 17.67 kg cm-1), pH (9.52 & 9.66), exchangeable sodium percentage (48.00 & 55.00), sodium adsorption ratio (45.14 & 54.10 (mmol/l)1/2) and calcium carbonate content (2.15 & 2.44 %). The gypsum application significantly improved infiltration rate (2.20 cm hr-1) and soil porosity (38.7 %) and reduced soil strength (16.74 kg cm-1), soil pH (9.35) exchangeable sodium percentage (39.00), sodium adsorption ratio (36.93 (mmol/l)1/2) over a period of thirty years. A significant CaCO3 build up in soil was also observed with gypsum application (3.28 % 4.56 %) as compared to its content at the start of study. Thus, it is concluded that in coarse textured soils of North west India, sodic waters up to RSC 12.0 me l-1 could safely be used crop production in combination with gypsum in loamy sand soil without any adverse effect on the physico-chemical characteristics of soil