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20145
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Subject: Biochemistry × End date: 2014 × Start date: 2014 × Type: Thesis × Thesis Type: M.Sc ×
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    ThesisItemOpen Access
    CHANGES IN VARIOUS ANTIOXIDANT PARAMETERS UNDER DIFFERENT ABIOTIC STRESSES IN WHEAT (Triticum aestivum L.)
    (Punjab Agricultural University, Ludhiana, 2014) Lovlace Kaur
    Antioxidant and phenolic metabolism were studied in two wheat cultivars PBW343 (ABA-lesser sensitive and drought sensitive), C306 (ABA-higher sensitive and drought tolerant) under different abiotic stresses and exogenous ABA supply. ABA regulation under stress involved decreases in lignin and/ or cell-wall ionically bound- peroxidases (CW-iPOX) in roots to increase root length, increases in nitric oxide (NO) signalling and detoxification mechanism, increases in proteolysis at early stage of stress to renew cellular proteins, decreases in oxidative toxicity (in terms of lesser superoxide anions radical (O2-.) and protein carbonylation) and decreases in secondary metabolism . This regulation showed poor working under water stress (WS) in PBW343 but improved on supplying ABA under WS. This regulation showed better working under salt stress (SS) / combined stress, CS (of salt plus water stress) than WS in PBW343. In C306 this regulation showed good working under WS where detoxification mechanism was almost uninduced. C306 roots showed a different ABA pathway for higher increases in root length under stresses which though involved decreases in lignin but increases in CW-iPOX and decreases in NO. Performance of C306 under SS/CS though was not varied higher from WS but it showed higher level of protein oxidation and higher level of secondary metabolism. Some salt-specific effects were seen in both cultivars, these were higher increases in NO, dehydroascorbate reductase (DHAR) and O2-.. Monodehydroascorbate reductase (MDHAR) and DHAR though were not ABA upregulated in both cultivars but their levels were higher in C306 than PBW343 under WS and were higher under SS/CS than under WS in PBW343.
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    ThesisItemOpen Access
    EFFECT OF EXOGENOUS PHENOLIC ACIDS ON ANTIOXIDANT RESPONSE IN WHEAT (Triticum aestivum L.)
    (Punjab Agricultural University, Ludhiana, 2014) Anupam Sharma
    In the present study, effect of exogenous salicylic acid (SA), gallic acid (GA) and ferulic acid (FA) on antioxidant response was investigated in wheat seedlings. For this, PBW 621 seeds were pre-treated with varying concentrations of SA, GA and FA and growth data was taken at 6th day after germination (DAG). In comparison to hydroprimed seedlings, application of 10-70 ppm of SA, 20-140 ppm of GA and 50-150 ppm of FA had growth promotory effects in wheat. Although at higher concentrations, SA (200 ppm) and FA (1000 ppm) inhibited seedling growth however GA even at 1000 ppm did not cause inhibitory effects. In comparison to water primed seedlings, 40 and 70 ppm of salicylic acid augmented antioxidant response by upregulating antioxidative enzymes viz. SOD, CAT, POX, APX and GR and increasing proline, ascorbate and total phenolic contents leading to reduced MDA content. Pretreatment with gallic acid (20-140 ppm) led to increase in the GR and APX activities along with the increase in proline, ascorbate and total phenolic contents. Wheat seedlings pre-treated with 100 and 150 ppm of FA showed upregulated CAT and POX activities which resulted in lower H2O2 content. Further, wheat seedlings pre-treated with 100 and 150 ppm of FA showed enhanced ascorbate and total phenolic contents. Therefore, lower concentrations of these phenolic acids i.e. 40 ppm of SA, 80 ppm of GA and 100 ppm of FA could be used to promote the antioxidant response in wheat. Antioxidant response, ferulic acid, gallic acid, salicylic acid, wheat
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    ThesisItemOpen Access
    Comparative biochemical and proteomic analyses of interspecific Gossypium species hybrid and its parental lines
    (Punjab Agricultural University, Ludhiana, 2014) Gurdeep Kaur; Sangha, Manjeet Kaur
    The study was aimed at comparing the biochemical and proteomic analyses of three different cotton allotriploids viz. F1861 x G. armourianum, F776 x G. armourianum, F1946 x G. armourianum and their parental lines viz. F1861, F776, F1946 and G. armourianum. The various biochemicals viz. chlorophyll a, chlorophyll b, total soluble sugars, reducing sugars, total phenols, carotenoids, tocopherols and crude protein were evaluated in leaf tissue collected fortnightly from September to December, 2012 from PAU Regional Research Station, Faridkot. The total soluble proteins extracted were subjected to protein profiling on PAGE and SDS-PAGE. The data was analysed as per standard procedure of CRD and heterosis was also calculated for studying deviation of hybrids over mid parent value. The various biochemicals viz. chlorophyll a, chlorophyll b, total soluble sugars, reducing sugars, total phenols, carotenoids, tocopherols and crude protein registered overall variation of 0.85 – 1.58mg/g FW, 1.15 – 2.05 mg/g FW, 26.27 – 83.88 mg/g DW, 15.27 – 75.9 mg/g DW, 9.95 – 36.41 mg/g DW, 0.34 – 1.54 mg/g DW, 5.87 – 12.67 μg/g DW, 20.93 – 30.85 % DW respectively. Most of the biochemicals estimated depicted significant variation among samples collected at each day. Almost all of the biochemicals estimated showed significant deviation in the hybrids from their mid parent value as indicated by heterosis calculations. The deviation was significant either positively or negatively. Protein profiling depicted differential changes in protein composition of synthetic alloploids over their parental lines. The SDS PAGE profile indicated the presence of some bands and the absence of others among the parents and the crosses, indicating that the genomic merger probably altered the expression of the proteins in the alloptriploids.
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    ThesisItemOpen Access
    A Study on anthocyanins and other biochemical constituents in different plant parts of brinjal (Solanum melongena L.)
    (Punjab Agricultural University, Ludhiana, 2014) Ankita Kumari; Chawla, Neena
    Fifty genotypes of brinjal bearing fruits of different colours (purple, pink, green and white) were evaluated for anthocyanin content in peel, flesh part and whole fruit in fresh tissue, whole fruits were analyzed for dry matter, total soluble sugars, total phenols, ortho-dihydroxy phenols and flavonols in 2012 and 2013. In both years, the peel had high anthocyanin content followed by whole fruit and flesh part. The highest anthocyanin content in peel, flesh and whole fruit was found in SR-312 (purple), SR-308 (green) and SR-303 (purple) respectively. Total phenols content varied in the range of 70.21 to 296.37 mg/100g DW with average value of 125.58 mg/100g in 2012 and in the range of 75.16 to 298.63 mg/100g DW with average value of 120.78 mg/100g in 2013. Highest total phenol content was found in G-415 (green) in 2012 and 2013. G-418 (green) and P-71 (purple) showed ortho-dihydroxy phenols content in the maximum range (80-100 mg/100g). The maximum flavonol content was found in BLEND-11-WR-2 (white). The activity of three enzymes ANS, PAL and TAL were studied in fruit and leaves of fourteen selected genotypes. The activity of ANS in leaves and fruits of green and white colour progressively decreased from 7 days to 21 days while a progressive increase was observed in purple fruits during the same period. The activity of PAL and TAL in both fruit and leaves increased till 14 days and then there was decrease in activity upto 21 days.
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    ThesisItemOpen Access
    Antioxidative defense system and grain quality evaluation of heat tolerant wheat genotypes
    (Punjab Agricultural University, Ludhiana, 2014) Amandeep Kaur; Harinderjeet Kaur
    The fifty genotypes of wheat in two trials Multi Location Heat Tolerance (MLHT) I and Multi Location Heat Tolerance (MLHT) II under timely and late sown conditions were sown in experimental fields of Plant Breeding and Genetics during the crop season 2011-12 to study the impact of heat stress on physiological parameters. The chlorophyll content, canopy temperature depression, days to heading, peduncle length, plant height, grain number per spike, grain weight per spike, spike number per spike, total biomass and grain yield were affected negatively under late sown conditions in all genotypes except genotypes such as GW 433, HD 3090, MP 3353, WH 1124 and RW 3705 from MLHT I and HD 3040, HI 8703, MP 3304, DBW 14, DL788-2, HUW 234 and NW 2036 from MLHT II. Genotypes GW 433, HD 3090, MP 3353 and WH 1124 from MLHT I and HD 3040, HI 8703 and MP 3304 from MLHT II were found to be less susceptible to heat stress as reflected by lower values of heat susceptibility index. Genotypes HI 1571, PBW 670, RAJ 4250 and WH 1123 from MLHT I and HI 8703, PBW 639 and WHD 946 from MLHT II were found to be susceptible to high temperature due to higher values of heat susceptibility index. Total 25 genotypes (tolerant, susceptible and checks) from both trials MLHT I and MLHT II were selected for the study of antioxidative defense system and grain quality evaluation. Genotype WH 1124 from MLHT I and genotypes HD 3040 and HI 8703 from MLHT II showed increased activity of antioxidant enzymes such as superoxide dismutase, peroxidase, ascorbate peroxidase and catalase indicated better antioxidant defense system against heat stress and hence found to be the best among the selected tolerant genotypes. GW 433, HD 3090, HD 3040 and HI 8703 from both the trials MLHT I and MLHT II showed higher grain appearance score, test weight, grain hardness, protein content, SDS-sedimentation value, grain plumpness, total sugars, dry gluten content, gluten index and better starch pasting characteristics under late sown conditions, hence can produce better quality grains. Genotypes WH 1124, HD 3090, GW 433 and HD 3040, HI 8703 from the trials MLHT I and MLHT II exhibited better antioxidative defense system and superior quality characteristics with higher yield under heat stress.