01755naa a2200193 a 450000100080000000500110000800800410001910000170006024501470007726000090022452011590023365000230139265000250141565300260144070000180146670000140148470000140149877300490151216467591995-08-16       1987    bl ---       0--  u    #d1 aSINGH, D. P.  aDiurnal patterns of canopy photosynthesis, evapotranspiration and water use efficiency in chickpea (Cicer arietinum L.) under field conditions  c1987  aDiurnal changes in net photosynthetic rate (PN), evapotranspiration rate (ET) and water use efficiency (WUE = PN/ET) of field grown chickpea (Cicer arietinum) L. cv. H-355) were studie from the vegetative phase through maturirty at Haryana Agricultural University Farm, Hissar, India. The maximum photosynthetic rate (PN max) increased from the initia vegetative phase to pod formation and declined at a rapid rate from pod filling to maturity. The response of PN to photosythetic photon flux density (PPFD) (400-700 mm) was temperature-dependent during the day, i.e. on cool days the PN rates were lower for certain quanta of PPFD during the first half than during the  second half of day, and vice versa on warm days, ET was affected both crop cover and evaporative demand up to flowering, but thereafter if was independent of crop cover and followed the course of evaporative demand. ET was related to air temperature during the day while PN was related to PPFD. There was a lag of two to three hours between PN max (around noon) and ET max (around 2 p.m.) WUE increased from the vegetative stage through flowering but decreased thereafter to maturity  aevapotranspiration  awater use efficiency  aCanopy photosynthesis1 aPETERS, D. B.1 aSINGH, P.1 aSINGH, M.  tPhotosynthesis Researchgv.11, p.61-69, 1987