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M. Sc. Dissertations

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2010 - 20114
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Subject: Plant Physiology × End date: 2011 × Start date: 2010 × Type: Thesis ×
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Now showing 1 - 4 of 4
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    ThesisItemOpen Access
    Phosphorus uptake, yield and quality parameters in wheat (Triticum aestivum L)
    (CCSHAU, 2010) Renu Bala; Munjal, Renu
    The present experimentation was carried out on ten wheat genotypes namely WH-147, Raj-4083, WH-1021, WH-1022, WH-1025, LOK-1, NW-2030, C-306, PBW-343 and PBW-550 with three level of phosphorus i.e. 20%, 50% and 100% in order to identify the genotypes efficient in phosphrous uptake and utilization, the effect of phosphrous doses on quality parameters of wheat grains and the root morpho-physiological traits associated with efficient phosphors uptake. The investigation involved pot studies under screen house conditions during the year 2008-09.Data was recorded for dry weight of root,stem and leaves,physiological parameters(Chlorophyll fluorescence, Assimilation rate, Transpiration rate, Stomatal conductance, Water use efficiency ),days to heading, days to Anthesis, days to Maturity, Grain Filling duration, Plant Height, No. of productive tillers/plant, biomass/plant, Spike length, Grain yield/plant Test weight, Phosphorus cont Quality parameter in grain . In this study day to heading, anthesis, maturity and grain filling duration got delayed at low P level (20%) as compared to 100% P. Raj-4083, WH-1022, NW-2030, WH-1025, C-306, PBW-343 and PBW-550 showed significant difference for root, shoot and leaf dry weight at different level of phosphorus during anthesis stage. WH-147 and Raj-4083 was better in maintaining WUE at different P level. Acid and alkaline phosphate activity increased with decrease in the P. Activity of both enzymes was highest in NW-2030. For majority of the yield components the genotypes Raj-4083, WH-147, LOK-1, NW-2030 and PBW-550 performed better at different P levels. Among all these seedling characteristics root length root/ shoot dry weight and no. of secondary lateral roots increased at 20% P, but shoot length decreased at 20% P. No. of secondary lateral roots was found as major determinant of P deficiency.
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    ThesisItemOpen Access
    Studies on epibrassinolide induced amelioration of high temperature stress in brassica juncea (L.) czern & coss
    (CCSHAU, 2010) Walke, Mahadev Bapu; Chhabra, M.L.
    The present investigations were undertaken to study the role of epibrassinolide (EBR) on seed germination, seedling growth, 50% seedling mortality, relative water content, membrane stability, free proline content, antioxidative enzymes and metabolites at seedling stage, while gaseous exchange and yield attributes at terminal stage in field grown Brassica juncea plants. When seedlings were grown at 25C, 30C or 35C, it was observed that 25C is optimum temperature for germination and seedling growth. The germination, speed of germination and seedling growth of Brassica juncea in general reduced when temperature was increased from 25C to 30C and 35C. Soaking seeds in EBR (10-6 M, 10-8 M or 10-10 M) for 2 hrs in general reduced germination, seedling growth and delayed seedling mortality. Higher the concentration of EBR used, more was the reduction in germination and seedling growth. Acclimation at sublethal temperature (32C) and EBR pretreatments (10-8 M and 10-10 M ) for 24 hrs prior to high temperature stress (45C) were found to be effective in imparting thermo protection at seedling stage, which is the crucial stage of plant establishment. These pretreatments helped seedling to recover from heat stress by improved relative water content, reduced per cent injury and increased free proline content. Increase in enzymatic activity of catalase, peroxidase, and also reduction in MDA, H2O2 content conferred thermotolerance. At flower cessation stage, compared to normal sown, in late sown crop the rate of photosynthesis and seed yield decreased significantly whereas, rate of transpiration and stomatal conductance increased. Rate of photosynthesis, transpiration and stomatal conductance increased in plants sprayed with EBR at flower cessation stage. Lower concentration of EBR (10-10 M) was more effective to bring consecutive improvement in gaseous exchange. EBR spray (10-10 M) increased the seed yield (13.6%) and oil content (4.23%) as compared to control. Lower concentration of EBR (10-10 M) in general was more effective in imparting thermotolerance in B. juncea.
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    ThesisItemOpen Access
    Studies on the ripening of Mango (Mangifera indica L.) cv. Dashehari by ethephon and calcium carbide
    (CCSHAU, 2011) Poonam Kumari; Sandooja, J. K.
    An expriement was conducted to compare the ripening caused by ethephon (source of natural ripening hormone, ethylene) and calcium carbide (source of acetylene and applied commercially) in mango fruits as compared to control. Physiological loss in weight increased with increase in the period of storage in all the treatments. There was no decay loss up to 6th day, however it was observed on 8th day of storage in all the treatments and further it increasd on 10th day of storage. Fruits treated with calcium carbide had higher physiological loss in weight, decay loss, sugars and total soluble solids as compared to fruits ripened with ethephon. However, acidity, ascorbic acid, cellulose and pectin content of fruits were lower in calcium carbide treated fruits as compared to fruits ripened with ethephon. Sugars (total, reducing and non-reducing) and total soluble solids increased with increase in period of storage up to 4th and 6th day of storage respectively in all the treatments and decreased thereafter whereas cellulose, pectin, acidity and ascorbic acid decreased with increase in the period of storage in all the treatments. Among the different treatments, calcium carbide @ 3g/kg was highly effective in increasing decay loss, total soluble solids and sugars and decreasing acidity, ascorbic acid, pectin and cellulose content. Fruits ripened with ethephon @ 250 ppm showed better ripening and sensory qualities.
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    ThesisItemOpen Access
    Physiological studies on the effect of salinity on germination and early growth in Gossypium hirsutum L. and Gossypium arboreum L.
    (CCSHAU, 2011) Kavita; Promila Kumari
    The present investigation was aimed on “Physiological studies on the effect of salinity on germination and early growth in Gossypium hirsutum L. and Gossypium arboreum L.” using various physiological parameters. Six cultivars of cotton (RCH-134, Bio-6488, H-1236, HHH-223, HD-123, AAH-1) were grown in screen house having four salinity levels as control, 4, 8, and 12 dSm-1. Results revealed that with progressive increase in salinity levels the seed germination, vigour index, relative water content of leaves, osmotic potential and stomatal conductance transpiration rate, as well as K+ content of leaves. Maximum reduction in seed germination was recorded in desi cotton cultivar HD-123 at highest level (12dSm-1) of salinity. A progressive increase in salinity levels on the other hand caused catalase, peroxidase activity and Na+ content of leaves enhanced. The maximum enhancement in catalase and peroxidase activity in leaf was observed in Bt. cultivars at both the sampling stages i.e at 30 and 60 DAS. Accumulation of Na+ content in leaves was maximum in desi cultivars HD-123 followed by American. Sodium content of leaves of all the cultivars of cotton increased with increasing salinity level; increase being found to highest in leaves of desi cotton cultivars. Potassium content of all cotton cultivars showed decreasing trend with increasing salinity levels. K+/Na+ ratio of leaves of all cultivars also decreased with increasing salinity level; decrease being highest in Bt. cultivars and minimum was recorded in desi cotton cultivars AAH-1. On the basis of the observations taken in the score-card it was found that Bt. cotton cultivars RCH-134 and Bio-6488 was tolerant to salinity. Both Bt. cotton cultivars (RCH-134 and Bio-6488) showed maximum no of polypeptide bands i.e 14 in SDS-PAGE, while American showed total number of thirteen polypeptide bands while desi cultivars had twelve in AAH-1 and fourteen in HD-123. Result revealed that with the progressive increase in salinity level from 4 to 12 Dsm-1 there was decrease in various physiological parameter enhanced viz; On the other hand, with the increase salinity levels increase in catalase, peroxidase enzymes and the Na+ content was recorded.