000			02262nam a22001697a 4500
999			_c161797 _d161797
082			_a551.6 _bATH/CO
100			_aAthul Boby C
245			_aComparative assessment of whole plant water use efficiency (wue) of coconut seedlings (cocos nucifera) to drought tolerance
260			_aVellanikkara _bAcademy of Climate Change Education and Research _c2017
300			_a131p
502			_aBSc-MSc (Integrated)
520			_aA study was conducted at ICAR-CPCRI, Kasaragod to determine the whole plant WUE of two dwarf (Malayan Yellow Dwarf (MYD) and Chowghat Green Dwarf (CGD)) and two tall varieties of coconut seedlings (Kalpatharu (KT) and Kalpa Pratibha (KP)) of coconuts. The seedlings were grown in large buckets and exposed to three moisture regimes- 100% ASM (available soil moisture), 50% ASM and 25% ASM. Coconut seedlings were found to be highly sensitive to moisture and observed that with the first observation made i.e., within 25 days after stress imposition there was significant decline in morphological and physiological traits. Plant height, collar girth, leaf number showed an increasing trend up to 57 days after 50% ASM imposition while at 25% ASM there was no further increment in growth of above parameters. Both Pn and leaf area which contribute to the biomass significantly declined under stress condition. However biomass accumulation over the stress period was high in KT and KP compared to CGD and MYD. Thus KT and KP had high WUE both under 50% and 25% ASM 5.48 g/L and 5.68 g/L and 5.42 g/L and 4.55 g/L respectively. CGD on the other hand had lower WUE at 50% ASM (3.68 g/L) and increased slightly at 25% ASM (3.84 g/L). WUE was the least in MYD both at 50% (3.54 g/L) and 25% ASM (2.74 g/L). The higher WUE in KT and KP was found to be imparted by high biomass partitioning to roots and drought tolerance mechanisms like epicuticular wax deposition and higher activity of antioxidant scavenging systems. Thus, tall varieties KP and KT are found to be better adapted to water deficit stress compared to the dwarf varieties CGD and MYD.
650			_aClimate Change Education and Research
700			_aHebbar, K B (Guide)
856			_uhttp://krishikosh.egranth.ac.in/handle/1/5810144192
942			_2ddc _cTH