Field Crops Research, 16 (1987) 231-241 231 Elsevier Science Publishers B.V., Amsterdam -- Printed in The Netherlands Influence of Water Deficits on the Water Relations, Canopy Gas Exchange, and Yield of Chickpea ( Cicer arietinum ) D.P. SINGH, PHOOL SINGH, H.C. SHARMA and N.C. TURNER* UNDP Centre of Soil and Water Management, Haryana Agricultural University, Hissar, Haryana 125004 (India) *Present address: Dryland Crops and Soils Research Program, Laboratory for Rural Research, Private Bag, P.O. Wembley, WA 6014 (Australia) (Accepted 15 January 1987) ABSTRACT Singh, D.P., Singh, P., Sharma, H.C. and Turner, N.C., 1987. Influence of water deficits on the water relations, canopy gas exchange, and yield of chickpea ( Cicer arietinum). Field Crops Res., 16: 231-241. Chickpeas (Cicer arietinum L., cv H-355) were subjected to four irrigation treatments after crop establishment: (i) unirrigated (D); (ii) irrigated until flower initiation [ 85 days from sow- ing (DAS)] and unirrigated thereafter (WD); (iii) unirrigated until active seed setting (129 DAS) and irrigated thereafter (DW); (iv) irrigated throughout (W). Several plant processes were measured on clear days between 85 and 144 DAS. The unirrigated plants had lower leaf water potentials, canopy evapotranspiration rates (ET), canopy photosynthetic rates (PN), plant dry weight and grain yield compared to the irrigated plants, but increased canopy-air temperature differences (Tc-T~). Cessation of irrigation at flowering induced a rapid decrease in canopy pho- tosynthesis and reduced the grain yield by 33% due to a decrease in the number of pods set. Irrigation from 129 DAS resulted in some recovery of grain yield resulting from the development of a small number of late pods with small seeds. Among yield components, water stress primarily affected the number of pods per plant and had little effect on the grain number per pod. Grain yield was linearly related to pod number, leaf water potential, and mean PN. INTRODUCTION Chickpea is one of the most important cool-season food legumes in the Indian subcontinent ( Sheldrake and Saxena, 1979 ). Because of poor irrigation facil- ities in the major chickpea-growing areas, about 85% of the 8 million ha of the crop is unirrigated, and grown on soils with limited water storage capacity, whereas it is known that the crop responds favourably to irrigation (Sharma et al., 1974; Singh et al., 1982b). 0378-4290/87/$03.50 © 1987 Elsevier Science Publishers B.V.