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Chaudhary Charan Singh Haryana Agricultural University, Hisar

Chaudhary Charan Singh Haryana Agricultural University popularly known as HAU, is one of Asia's biggest agricultural universities, located at Hisar in the Indian state of Haryana. It is named after India's seventh Prime Minister, Chaudhary Charan Singh. It is a leader in agricultural research in India and contributed significantly to Green Revolution and White Revolution in India in the 1960s and 70s. It has a very large campus and has several research centres throughout the state. It won the Indian Council of Agricultural Research's Award for the Best Institute in 1997. HAU was initially a campus of Punjab Agricultural University, Ludhiana. After the formation of Haryana in 1966, it became an autonomous institution on February 2, 1970 through a Presidential Ordinance, later ratified as Haryana and Punjab Agricultural Universities Act, 1970, passed by the Lok Sabha on March 29, 1970. A. L. Fletcher, the first Vice-Chancellor of the university, was instrumental in its initial growth.

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2009 - 200912010 - 20151
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Subject: Biochemistry × Author: Ekta × Start date: 1998 ×
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    Biochemical evaluation of drought resistance in chickpea (Cicer arietinum L.)
    (CCSHAU, 2015) Ekta; Singal, H.R.
    The present study was carried out to evaluate drought induced changes in chickpea genotypes and their F3 progeny lines. The chickpea genotypes viz. drought sensitive (HC-1) and drought tolerant (ICC-4958 and RSG-931) were grown under both irrigated and drought conditions and the progeny lines of the crosses viz. HC-1×ICC-4958 and HC-1×RSG-931 were grown under drought condition created by withholding irrigation. The effect of drought stress was observed on oxidative stress, membrane integrity, antioxidative system, osmolytes accumulation and protein profile in relation to changes in plant water status in leaves and roots at 50% flowering and 50% podding stages. The water potential of leaves, osmotic potential and RWC of leaves and roots decreased in all the genotypes. However, the magnitude of reduction in RWC was more in drought sensitive genotype. Similarly, the reactive oxygen species (superoxide radicals and H2O2) and lipid peroxidation (MDA content and LOX activity) increased in response to water deficit and the increase was more in both the tissues (leaves and roots) of sensitive genotype at both the stages (50% flowering and 50% podding). Drought stress resulted in increase in the activities of SOD, POX, GR in all the genotypes, but the increase was more in both the tolerant genotypes. Contrarily, reduction in CAT activity was observed in both the tissues at both the stages in all chickpea genotypes. Likewise, APX activity declined in leaves of both the drought tolerant genotypes only at 50% flowering stage, but in roots its activity increased at both stages. Ascorbic acid and glutathione content were found to be more in both the tissues of all the chickpea genotypes under water limiting condition, however, the percent increase was more in tolerant genotypes. Decline in osmotic potential in both the tissues may be due to accumulation of proline and total soluble sugars. Further, increase in pyrroline-5-carboxylate reductase activity and decline in proline oxidase activity observed in leaves and roots of all the chickpea genotypes under stress condition is in agreement with higher proline levels. Decrease in protein content was observed in both the tissues. However, new protein bands appeared under drought stress in all genotypes as revealed by SDS-PAGE. Among the progeny lines of both the crosses, the lines I-6, I-7, I-14, I-16, R-2, R-9 and R- 10 showed better performance in terms of physiological and biochemical parameters as compared to their drought tolerant parent, under drought stress condition and hence, are the promising lines which may be used in plant breeding programmes aimed at developing drought resistant varieties.
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    ThesisItemOpen Access
    Isolation, partial purification and characterization of sucrose synthase from thermotolerant wheat (Triticum aestivum L.)
    (CCSHAU, 2009) Ekta; Singal, H.R.
    Wheat grain is the dominant grain of world commerce and is the staple food of millions of people world wide. High temperature beyond 300C which is usually encountered during later part of grain filling period, affects grain yield (reduction by 20-50 per cent) and grain quality. Starch is the major storage carbohydrate in wheat grains. It is synthesized from sucrose which is the principal product of leaf photosynthesis and transported to the wheat grain. Sucrose synthase is the first enzyme and an important link in sucrose-starch conversion pathway. Keeping above in view, the present investigation was conducted to purify and characterize sucrose synthase from thermotolerant wheat. Sucrose synthase was purified to near homogeneity (as revealed by single band on Native-PAGE) from immature grains (21 days after anthesis) of thermotolerant wheat WH-1021 by using conventional protein purification techniques viz. ammonium sulphate fractionation, gel filtration through sephadex G-100 and DEAE-cellulose ion exchange chromatography. The enzyme was purified about 27 fold with approximately 37 per cent recovery. The molecular weight as determined by gel filtration and subunit molecular weight as determined by SDS-PAGE (single band) were found to be 269 KDa and 63 KDa respectively indicating that enzyme is a homotetramer. The purified enzyme exhibited optimum activity at 370C temperature and pH 6.5. It was thermostable upto 500C. The activity followed Michaelis-Menten kinetics with Km value of 14.28 mM and 1.18 mM for sucrose and UDP, respectively. Among the various nucleotides tested the enzyme was highly specific for UDP as substrate. The kinetic studies revealed that sucrose synthase catalysed the sucrose degradation by ping-pong mechanism. The enzyme activity was inhibited by Mn2+ (38.5 % inhibition) while NO3- stimulated (20.8% stimulation) the activity at 2 mM concentration. Amongst various metabolites tested NADP+ and G-6-P were found to be the potent inhibitors of purified sucrose synthase (inhibiting the enzyme activity by 16 and 34%), respectively. To summarize, higher thermostability of enzyme is suggestive of enzyme’s adaptation to high temperature stress.