Browsing by Author "Prakash G. Bhat"

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    Epicuticular waxes, lipids and membrane stability of cocoa trees in relation to drought tolerance
    (2007-02-08) Prakash G. Bhat; Daniel, E.V.; Balasimha, D.
    Higher leaf turgor was maintained in tolerant accession types of cocoa during dry periods which was accompanied by higher wax deposition. There were however no qualitative changes in wax composition between accession types. The lipid content decreased due to stress. Degree of unsaturation was lower, and total sterol/phospholipid ratio was higher with lower electrolytic leaching in tolerant accessions as compared to susceptible ones, especially under stress. All these changes in wax and lipid fractions help cocoa in better adaptation to drought by improving membrane stability.
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    Influence of environmental factors on photosynthesis in cocoa trees
    (Elsevier Science Publishers B.V., Amsterdam, 1991) Balasimha, D.; Daniel, E.V.; Prakash G. Bhat
    The photosynthesis of cocoa (Theobroma cacao Linn.) as influenced by light temperature and vapour pressure deficit (VPD)was studied in the field. Net photosynthetic rate (PN), transpiration rate and stomatal conductance showed significant seasonal variations. PN was highest during periods of low evaporative demand (low VPD). Diurnal patterns of these parameters indicated transient midday water deficits which reduced PN. Optimum temperature for PN was 31-33C and light saturation occurred at 400 μmol m-2 s-1. The CO2, compensation concentration was 100 ppm. Drought tolerant accessions maintained higher leaf water potential than drought-susceptible types in dry months. There was no significant difference in PN between tolerant and susceptible accession types.