Organic input management for sustaining productivity of seed spices under saline water irrigation. In: Advances in salinity and sodicity management under different agro-climatic regions for enhancing farmers income

Abstract

The availability of fresh water for agricultural use is declining in many areas of world due to increasing water needs of industries and municipalities. Thus agriculture faces challenges of using low quality waste water and saline water for crop production. Many studies indicate that these water resources traditionally classified as unsuitable for irrigation can be used successfully to grow crops without long-term hazardous consequences to crops and soils if proper management strategies are established. These strategies include adopting advanced irrigation technology, selection of salt tolerant crops, leaching of salts below the crop root zone. Water scarcity is becoming one of the major limiting factor for sustainable agriculture in the semi arid regions of the world. In India the entire arid and semi-arid regions have been characterised by low rainfall and has the problem either of water scarcity or poor quality groundwater. The use of saline/alkali ground water posses a major threat to plant growth and health, which is mostly observed in semiarid parts (Minhas and Bajwa, 2001). In India, the regions identified for poor quality water are major parts of Rajasthan, Gujarat, Haryana, North western UP and South western Punjab. Poor quality water constitutes 32-84 % of ground water surveyed in different parts of India is either saline or alkali (Minhas, 1996). Saline water upto 11 dS/m has been used successfully for commercial irrigation for a number of crops globally (Rhodes et al., 1992). However, in order to assure maximum yield form crops irrigated with saline water, it is necessary to develop special management techniques. Presently drip irrigation is widely regarded as the most promising irrigation system to use saline water. Several factors contribute to the good results obtained with saline water irrigation using drip irrigation under protected structures. (I) less water use results in less salt deposited on the beds, (ii) avoidance of leaf burn, (iii) high frequency drip irrigation prevents the soil from drying out between irrigations, thereby avoiding peaks in salt concentration and concomitant high osmotic potentials and (iv) salts are continuously leached out from the wetted section and accumulate at the wetting front away from the active root zone.