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2011 - 20134
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Subject: Agricultural Biochemistry × Start date: 2005 × Thesis Type: M.Sc ×
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Now showing 1 - 4 of 4
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    ThesisItemOpen Access
    BIOCHEMICAL BASIS OF HARDSEEDEDNESS IN VIGNA SPECIES
    (2011) Ahuja, Richa
    The present investigation was undertaken to study percent hardseededness, seed coat constituents and variation in the biochemical composition of cotyledonary tissue of 10 Vigna species viz., SML832, PAU911, SML668, ML818, MASH218, MASH1008, MASH338, MASH114, RBL1 and RBL6. Seeds from these Vigna species were stored in cloth bags for 180 days at room temperature and the effect of storage period on germinability, vigor index and chemical composition of seeds was studied. The % hardseededness in different Vigna species varied from 14-82% at 24 h and 8-68% after 48 h soaking period. The % hardseededness in different Vigna species decreased with storage of seeds upto 180 days under ambient conditions. The seed coats of hard lines contained higher cellulose and hemicellulose content as compared to those from soft lines. There was non-significant variation in the % neutral detergent fiber, % acid detergent fiber and tannin content in seed coats and total soluble sugars, reducing sugars, phenols and phytate content in the cotyledonary tissue of these Vigna species. However, total lipid content varied significantly. At harvest, the germination % and vigor index values were higher in soft lines as compared to hard lines. The germination % and vigor index values in hard lines increased with the storage period upto 180 days. Lipid peroxidation values increased significantly with storage period in seeds of various Vigna species studied whereas catalase and peroxidase activities decreased. The total lipid content in seeds of all the Vigna species decreased whereas phenolic content increased with the storage period. The results of the present study suggests that although the % hardseededness in different Vigna species decreases with increasing storage period but the seed deterioration occurs with the passage of time.
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    ThesisItemRestricted
    EFFECT OF PUTRESCINE AND HIGH TEMPERATURE ON THE ANTIOXIDANT ENZYMES IN WHEAT (Triticum aestivum L)
    (Punjab Agricultural University, Ludhiana, 2013) Rashpal Kumar
    Effect of putrescine (Put) and high temperature (HT) on the responses of wheat (Triticum aestivum L) seedlings or developing grains was studied in six wheat cultivars (PBW 343, C 273, C 306, PBW 550, PBW 621 and HD 2967) raised in the laboratory (25o or 32oC) in petri dishes for seven days or in the field under normal (Nov, 2011) and late (Dec, 2011) planting conditions. High temperature significantly reduced root/shoot lengths and dry weights of all the six cultivars, whereas Put ameliorated this effect by increasing these attributes. C 306 and C 273 showed higher root/shoot lengths and dry weights over PBW 550, PBW 621. High temperature significantly increased the activities of ascorbate peroxidase (APX), guaiacol peroxidase (GPX), superoxide dismutase (SOD) and catalase (CAT) in correspondence with an increased membrane injury index (MII) and contents of thiobarbituric acid reactive substances (TBARs) and H2O2. Application of Put under HT further elevated activities of these enzymes whereas MII and contents of TBARs, H2O2 were reduced. Infact, Put treated seedlings performed better in terms of antioxidant response under HT than seedlings in absence. Developing grains at mid milky (15 DPA) and at maturity stages (30 DPA) also showed higher activities of APX, GPX, CAT and SOD in C 306 than PBW 343 both under normal and late sown conditions. C 306 showed lower MII, TBARs content and DAO, PAO activities over PBW 343. Similar to seedlings, activities of these enzymes in grains were enhanced with Put whereas the contents of MII, TBARs content, DAO and PAO activities were reduced in both the cultivars at 15 and 30 days post anthesis. Substantial higher activities of these enzymes in the developing grain at HT revealed their significant role in scavenging free radical and thus overcoming oxidative stress. Various marpho-physiological parameters like plant height, peduncle length, 1000 grain weight and number of grains per ear were decreased in late sown crop. However, Put application under HT stress increased these parameters. Overall, it appears that upregulation of the antioxidant system b y Put in wheat cultivars contributes to better protection and membrane integrity in root, shoot and grains against HT through reduced MII and TBARs contents.
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    ThesisItemOpen Access
    ANALYSIS OF ABA-DEPENDENT ANTIOXIDANT RESPONSE OF WHEAT SEEDLINGS UNDER THE INFLUENCE OF EXOGENOUS SUGARS
    (Punjab Agricultural University, Ludhiana, 2013) Sandeep Kaur
    Sugar(Glucose; G and Sucrose; S) regulation of seed germination, growth and antioxidant potential, and involvement of ABA biosynthesis in these regulations were studied in two wheat cultivars varying in ABA sensitivity, where C306 was ABA-higher sensitive and PBW343 was ABA-lesser sensitive. Two concentrations (1.5% and 3%) of both sugars were used for germination and growth experiments where sodium tungstate was used as inhibitor of ABA biosynthesis. Germination inhibition was observed under both sugars supply but ABA biosynthesis was involved only under 3% S in PBW343 and 1.5% S in C306 otherwise not involved in such inhibition. Growth of seedlings was inhibited under both concentration of G and under 3% S in both cultivars where ABA biosynthesis contributed in such inhibition under 1.5% G in both cultivars and 3% S in PBW343. Growth was stimulated under 1.5% S, it involved ABA biosynthesis in both cultivars. Increases in antioxidant enzymes were higher under G than under S in both cultivars and were higher in C306 than PBW343 under both sugar supply. These increases involved ABA biosynthesis in both cultivars. Reduced state of ascorbate was affected under G while increased under S in roots and shoots of PBW343. Reduced state of ascorbate was increased under both G and S in shoots but decreased in roots of C306. Maintainence of reduced state of ascorbate under S involved ABA biosynthesis in both cultivars. Roots of C306 showed toxicity symptoms under G and S where there were concomitant increases in dehydroascorbate, malondialdehyde, H2O2 and decreases reduced state of ascorbate.
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    ThesisItemRestricted
    Productivity of cotton (Gossypium hirsutum L.) in relation to organic and inorganic nutrition
    (Punjab Agricultural University, Ludhiana, 2012) Jagdeep Singh; Saini, K. S.
    A field investigation entitled, “Productivity of cotton (Gossypium hirsutum L.) in relation to organic and inorganic nutrition” was carried out at Student’s Research Farm, Department of Agronomy, Punjab Agricultural University, Ludhiana during kharif 2011. The experimental field was under organic vs chemical farming system with permanent layout from 1996. Eight treatments N50(FYM)+GM+RI, N50(FYM)+GM+RR, N75(FYM)+RI, N75(FYM)+RR, N50(F)+GM+RI, N50(F)+GM+RR, N75(F)+RI, N75(F)+RR were studied under randomized block design (RBD). The soil of the experimental field was sandy loam with normal pH and EC, high in OC, P and medium in N and K in organic treated plots and medium in OC and K, low N and high P in inorganic treated plots. Microclimate of crop canopy was modified by the treatments where nitrogen was applied through organic source by increasing PARI % and relative humidity and by decreasing soil and crop canopy temperature. Yield attributing character like higher dry matter production, monopodial and sympodial branches, number of picked bolls were significantly higher in treatments where nitrogen was applied through organic source of nutrition as compared to inorganic source of nutrition. Hence maximum seed cotton yield (25.8 q ha -1 ) was recorded with N50(FYM)+GM+RI which was 29.6 % higher than N75(F)+RR i.e. recommended dose of fertilizer. Fibre quality parameter like fibre fineness, fibre elongation, fibre strength, Rd value and b + was not affected significantly by organic and inorganic source of nutrition. GOT, seed index and lint index was also unaffected by different source of nutrition. Oil content of cotton seed was significantly higher with N75(FYM)+RI i.e. 19.85 percent. Soil physico-chemical properties were also improved by organic source of nutrition as compared to inorganic source of nutrition