Browsing by Author "Kasturi Bai, K.V."

Now showing 1 - 20 of 75
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    Adaptive mechanism of coconut palms in the changing environment conditions for higher production
    (2007-02-08) Rajagopal, V.; Kasturi Bai, K.V.; Naresh Kumar, S.
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    Ammonium enhances the nitrate induced nitrate reductase activity in coconut (Cocos nucifera L.) leaves
    (2007-02-08) Shivashankar, S.; Kasturi Bai, K.V.
    Induction of nitrate reductase (NR) activity by nitrate in leaves of low and high yielding coconut palms was markedly different, requiring different levels of nitrate for optimum induction. Ammonium enhanced induction of NR activity by nitrate, under both light and dark conditions. Nitrate uptake was also enhanced in the presence of ammonium in the induction medium. It is postulated that ammonium might bring about the activation of NR by binding to an allosteric site on the enzyme in addition to its role in inducing NR synthesis.
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    Assay of enzymes in coconut cultivars and hybrids under non-stress and stress conditions
    (2007-02-08) Kasturi Bai, K.V.; Rajagopal, V.; Chempakam, B.; Prabha, C.D.
    Coconut palms of three tall varieties (West Coast Tall (WCT), Philippines Ordinary (PO) and Andaman Ordinary (AO), two dwarf varieties (Malayan Yellow Dwarf (MYD) and Gangabondam (GB)) and three hybrids (WCT x Chowghat Orange Dwarf (COD), COD xWCTand WCT x WCT) were assayed for the activities of stress sensitive enzymes viz., acid phosphatase (APH), L-aspartate : 2 Oxoglutarate amino transferase (AOAT), Superoxide dismutase (SOD), Peroxidase (POD) and Polyphenol Oxidase (PPO) during the two distinct stages viz., non-stress (September / October) and Stress (February / March) of 1989 and 1990. In general, there was stress-induced increase or decrease in the activity of enzymes among the cultivars/hybrids, based on which they were ranked. The cultivar/hybrid with higher activities of SOD and POD and lower activities of PPO, APH and AOAT could be designated as drought tolerant. Accordingly, the order of tolerance was found to be WCT x WCT > WCT > PO = WCT x COfr > AO > GB = COD x WCT > MYD.
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    Assessment of diversity in coconut varieties for drought responsive physiological traits
    (Journal of Plantation Crops, 2006-08) Kasturi Bai, K.V.; Rajagopal, V.; Arunachalam, V.
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    Biochemical changes and leaf water status of coconut genotypes differing in drought tolerance
    (2007-02-08) Shivashankar, S.; Nagaraja, K.V.; Voleti, S.R.; Kasturi Bai, K.V.
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    Breeding for drought tolerance in coconut: Status and potentials
    (2007-07-19) Rajagopal, V.; Kasturi Bai, K.V.; Kumar, N.
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    Changes in leaf carbohydrates in relation to commencement of flowering in coconut palm
    (1979) Kasturi Bai, K.V.; Ramadasan, A.
    Changes in leaf carbohydrates were monitored in a group of young palms for a duration of three years during which period six of them commenced flowering. The changes in cafbohydrate fractions, as influenced by the environmental factors, in the palms that commenced flower­ing, during the period under study are discussed.
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    Characterisation of drought tolerance in coconut
    (1993) Rajagopal, V.; Shivashankar, S.; Kasturi Bai, K.V.
    Coconut palms experience moisture stress of different magnitudes depending upon the extent of dry spell. Investigations on drought tolerance centred around the morphological observations on leaf and inflorescence characters, the physiological parameters like stomatal regulation and water potential components and biochemical aspects such as epicuticular wax and assay of certain sensitive enzymes. Out of the 23 genotypes screened, ten were found to possess desirable traits to withstand moisture stress. These included high stomatal resistance with low transpiration rate, high leaf water potential, high leaf-wax content, and relatively stable enzyme activities during moisture stress. Based on the above features, the released hybrids like LO x GB, LO x COD, WCT x COD are classified as drought tolerant. A rapid screening method has been developed to evaluate a large number of samples.
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    Chemical induction of dwarfism in coconut
    (2007-02-08) Kasturi Bai, K.V.; John George
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    Chlorophyll flourescence transients with response to leaf water status in coconut
    (2006-12) Kasturi Bai, K.V.; Rajagopal, V.; Naresh Kumar, S.
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    Coconut
    (2017) Naresh Kumar, S.; John Sunoj, V; Muralikrishna, K.S; Hebbar, K.B; Rajagopal, V; Kasturi Bai, K.V.; Chowdappa, P
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    Comparative performance of released cultivars and hybrids of coconut for dry matter production and yield
    (2007-02-08) Kasturi Bai, K.V.; John George
    Coconut cultlvars and hybrids viz., West Coast Tall, Chandra kalpa, Pratap, Keraganga, Chandra sankara, takshaganga and Chandralaksha were evaluated tor leaf traits, dry matter production and yield to identify the superior cultlvar among the released ones. The cultivars and hybrid showed significant differences in the above parameters. Based on the results, the traits for higher dry matter production and yield have been delineated. v Among the cultlvars and hybrids the performance of Keraganga (WCTxCBGD) and lakshaganga (LCTxCBCD) f was found to be better than the others in terms of leaf traits, dry matter production and yield. The observations clearly indicated that total nut production per se is not an important criteria for crop improvement programmes, but harvest index (HI) which gives an indication of the partitioning of total dry matter (TDM) towards the economic yield (l.e,copra outum) is the important trait for improving the production potential of the palms. Since the determination of TDM in coconut is very tedious and time consuming, partitioning of total nut dry matter towards copra can be used as an important trait for crop improvement programmes.
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    Comparative study of coconut genotypes for components of photosynthesis and respiration
    (2007-02-08) Shivashankar, S.; Kasturi Bai, K.V.; Ramadasan, A.
    The three coconut genotypes, West Coast Tall (WCT), Chowghat Dwarf Orange (CDO) and the hybrid WCTxCDO (TxD) were com-pared for the rate of apparent photosynthesis, dark respiration, chlorophylls a and b, total carotenoids, relative assimilation rate (RAR), leaf area, and stomatal frequency. With die exception of WCT, the rate of photosynthesis was not correlated with yield, There was significant difference in the rate of photosynthesis between TxD and WCT. CDO exhibited higher dark respiration as compared to WCT and TxD. TxD had significantly higher amounts of total chlorophylls than WCT and CDO. Stomatal frequency was not related with the rate of photosynthesis. The total leaf area of T x D was the highest followed by WCT and CDO. The results indicate that the total leaf area might be an important factor determining productivity.
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    Criteria for identification of coconut palms in situ tolerant to abiotic stresses in farmers fields
    (2006-10) Naresh Kumar, S.; Rajagopal, V.; Kasturi Bai, K.V.
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    Day time fluctuations in photosynthetic parameters and water relations in juvenile coconut palms grown under rainfed and irrigated conditions
    (2007-02-08) Rajagopal, V.; Naresh Kumar, S.; Kasturi Bai, K.V.; Laxman, R.H.
    Day time (7 h to 18 h) fluctuations in photosynthetic parameters (net photosynthetic rate, Pn; stomatal conductance, gs; internal CO2 concentration, Ci); water relations (leaflet water potential, Yiear; transpiration rate, E) and weather parameters (photosynthetically active radiation, PAR; leaflet temperature, Tleaff; air vapor pressure deficit, VPD) were estimated in juvenile palms of coconut grown under rainfed and irrigated conditions. Variations in values and day time fluctuations in photosynthetic parameters and water relations were observed between palms grown under rainfed and irrigated conditions, Pn, E and gs were maximum between 09:00 and 11:30 and 15:00 and 16:00 h. Ci and ψie,r were least during mid-day. Mid-day slump in Pn and gs was observed. Tleaf, PAR and VPD were maximum between 09:00 and 16:00 h. E and VPD were positively correlated. Rainfed palms had higher Tleaf, Ci, CilCa and leaf to ambient temperature difference (∆T) and lower Pn, ψr and E compared to the irrigated palms. Instantaneous and intrinsic water use efficiency increased under mild water-deficit conditions. It is apparent that under rainfed conditions the carbon assimilation efficiency was low compared to irrigated condition. VPD and Ar influenced gs and water relations during day time which predominantly determined the variations in photosynthetic efficiency of coconut under irrigated and rainfed conditions.
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    Distribution of nutrients in three varieties of cardamom
    (1981) Abdul Khader, K.B.; Wahid, P.A.; Kasturi Bai, K.V.; Mohammed Syed, A.A.
    The uptake and concentration of nutrients in different parts of cardamom plants were studied in three important cultivars. Differences were observed in nutrient distribution pattern. In general, cardamom plants were found to accumulate major and secondary nutrients in the order of K> N ·Ca> Mg> P > Na and micronutrients in the order of Mn > Fe >Zn > Cu.
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    Drought management in plantation crops
    (2007-02-08) Rajagopal, V.; Kasturi Bai, K.V.; Naresh Kumar, S.
    Drought is major constraint for crop producing in plantation crops under rainfed conditions. in coconut soil water plant relationships have been worked out. In sandy loam soil, water deficit of 110 mm is the critical level at which coconut suffered most due to moisture stress. The drought tolerant characters has been identified by screening the germplasm for specific traits sensitive to stress conditions. The sensitive critical stages to drought stress has been identified in Coconut and Arecanut. The strategies for drought management like conservation of available soil moisture and efficient use of available water resources for higher productivity have been discussed in detail. Development of molecular makers; for such desirable drought tolerant traits is one of the future goals, so as to transfer it into promising genotypes.