Loading...
Thesis
Browse
33 results
Search Results
ThesisItem Open Access Physiological and biochemical evaluation for acquired thermotolerance in pigeonpea (Cajanus cajan L. Millsp.) at seedling stage(Punjab Agricultural University, Ludhiana, 2018) Navneet Kaur; .) Jagmeet KaurThe present investigation was conducted to study the physiological and biochemical evaluation for acquired thermotolerance in three pigeonpea (Cajanus cajan L. Millsp.) genotypes at seedling stage. Heat acclimation (45°C for 3h) and salicylic acid (0.5 mM and 1 mM for 3h) pre-treatments induced physiological changes in terms of seedling length, seedling weight, RGR, electrolyte leakage and RWC and biochemical changes in terms of cellular respiration, total soluble sugars, proline content, photosynthetic efficiency, MDA and H2O2 content and changes in antioxidant enzyme activities (CAT and POX) imparting thermotolerance. These pre-treatments conferred protection against heat stress through improved seedling growth, reduced electrolyte leakage, increased RWC, increased accumulation of sugars and proline, improved photosynthetic efficiency, reduced MDA and H2O2 content. Antioxidant defense system was induced in terms of CAT (average 1.02 fold increase in heat acclimated, 0.77 fold in 0.5 mM SA and 1 fold in 1 mM SA) and POX (average 1.30 fold increase in heat acclimated, 1.24 fold in 0.5 mM SA and 1.37 fold in 1 mM SA) activity in all genotypes. Separation of proteins through SDS-PAGE revealed the accumulation of some new proteins (heat shock proteins) of low and high molecular weight in heat acclimated seedlings to overcome the harmful effects of heat stress. Among the three genotypes, AL 1931 performed best and acquired maximum thermotolerance. Although both the pre-treatments resulted in induction of thermotolerance but SA pre-treatment proved better in the present study.ThesisItem Open Access Effect of genotypic variation and seeding practices on coronal root formation in wheat(Punjab Agricultural University, Ludhiana, 2018) Paramdeep Kaur; Sarlach, R.S.The present study entitled “Effect of genotypic variation and seeding practices on coronal root formation in wheat” was carried out to explore diversity in coronal root parameters (number of coronal roots per tillers, effective anchoring length (cm), effective anchoring thickness (mm), angle with respect to vertical root axis and first internodal length (cm) of coronal roots) among genotypes under different seeding rates and seeding depths. The study was conducted at the experimental area of Wheat section, Department of Plant Breeding and Genetics, Punjab Agricultural University, Ludhiana during two successive growing seasons of 2016-17 and 2017-18. In first growing season, 28 genotypes under different tillage systems (normal, deep sowing and zero tillage) were sown. On basis of coronal root parameters and morphological parameters 18 genotypes were selected to be sown in second growing season. In 2017-18 eighteen genotypes were sown in nine seeding conditions representing combination of 3 seeding depths (2 cm, 5 cm, 8 cm) and 3 seeding rates (4g/0.64 m2, 8g/0.64 m2, 16g/0.64 m2). Coronal root parameters were recorded at vegetative and anthesis stage. Coronal roots performed best under 2 cm and 5 cm seeding depth with 4g seeding rate. Based on the performance of genotypes under different seeding practices and lodging scores BWL 1771, HD 2967, BWL 3473, PBW 723, HD 3086 can be regarded as lodging tolerant genotypes on the basis of coronal root parameters.ThesisItem Open Access Herbaceous plant diversity and its nutrient status in various land use systems of selected localities in Punjab(Punjab Agricultural University, Ludhiana, 2018) Jashanpreet Kaur; Sharma, RajniThe present study on herbaceous plant diversity of three land use systems viz fallow land, canal bunds and cultivated land at two locations Ludhiana and Sangrur revealed overall sixty seven plant species at these sites. Among these fifty two plants were dicots and fifteen were monocots. Plants were distributed in twenty seven families out of which Poaceae and Asteraceae were dominant. Variations were recorded for plant species in all the land use systems and locations. Only few differences in emergence, flowering, fruiting, seed maturity and senescence of plant species was observed when land use systems were compared. For morphological parameters, the maximum plant height (178.16 cm) and shoot length (183.50 cm) was recorded for Saccharum spontaneum whereas diameter (19.23 cm) was recorded maximum for Ricinus communis and root length (23.5 cm) was maximum for Conyza bonariensis. Diversity indices values showed variations with change in months, land use systems and locations. Among land use systems of both locations, Density/m2 was recorded to be maximum for Parthenium hysterophorus (10.5 m-2) of fallow land (Sangrur) in September and IVI (115) was maximum for Amaranthus viridis of cultivated land (Ludhiana) in June. Comparison of mean values of Shannon Wiener index (2.30) and Brillouns index (2.16) reflected that mean values were maximum for fallow land (Sangrur) which reflected presence of maximum diversity in this system. Simpson diversity index mean values (0.88) were maximum for canal bunds of both locations reflecting maximum diversity of dominant plant species. Eveness index representing equal number of individuals per species was maximum for fallow land (0.77) (Ludhiana) followed by cultivated land. Annual values for total biomass (5733 kg/ha), nitrogen uptake (96.66 kg/ha), phosphorus uptake (21.55 kg/ha) and potassium uptake was recorded to be maximum for fallow land (Sangrur). On monthly basis, for July maximum biomass (3744.33kg/ha), nitrogen uptake (66.15kg/ha), phosphorus uptake (17.71) and potassium uptake (52.03kg/ha) was recorded.ThesisItem Restricted Effect of sodium nitroprusside on post harvest keeping quality of gladiolus spikes(Punjab Agricultural University, Ludhiana, 2018) Mittal, Isha; Jhanji, ShaliniThe present investigation entitled “Effect of sodium nitroprusside on post harvest keeping quality of gladiolus spikes” was undertaken in Research Farms of Floriculture and Laboratories of Botany of Punjab Agricultural University during the year 2016-18. The spikes of gladiolus var. Punjab Glad-1 were pulsed for 20 hrs with SNP solutions (100 mg l-1, 200 mg l-1, 300 mg l-1 and 400 mg l-1) alone and in combination with sucrose (20%) and aluminium sulphate (400 mg l-1) and held in SNP solutions (50 mg l-1, 100 mg l-1, 150 mg l-1 and 200 mg l-1) alone and in combination with sucrose (2%) and aluminium sulphate (400 mg l-1). The pulsing solutions of SNP @ 100 mg l-1 and 200 mg l-1 and holding solutions containing SNP@50 mg l-1 and 100 mg l-1 significantly hastened the opening of basal floret, increased size, number of florets open at one time, per cent opening of florets, vase life, water/solution absorbed and decreased the pH of solutions whereas pulsing with SNP @ 400 mg l-1 or holding spikes in 200 mg l-1 SNP adversely affected the quality parameters. Further, to have an insight into concentration dependent response of SNP, the physiological and biochemical analysis of florets of spikes treated with four pulsing SNP solutions viz. 100 mg l-1, 200 mg l-1 supplemented with sucrose and aluminium sulphate, 300 mg l-1 and 400 mg l-1 and four holding SNP solutions viz. 50 mg l-1, 100 mg l-1 supplemented with sucrose and aluminium sulphate, 150 mg l-1 and 200 mg l-1 was done at four developmental stages. The results pertaining to membrane stability index, relative water content, total soluble sugars, total protein content, catalase and peroxidase activity supported the results of keeping quality parameters. Thus, sodium nitroprusside @200 mgl-1 with sucrose and aluminium sulphate could be used as pulsing and @100 mgl-1 with sucrose and aluminium sulphate as holding solution to improve the post harvest quality of spike.ThesisItem Open Access Genotypic differences and environment influence on epicuticular wax in wheat(Punjab Agricultural University, Ludhiana, 2018) Toor, Ramandeep Kaur; Sarlach, R.S.The present research work entitled “Genotypic differences and environment influence on epicuticular wax in wheat” was conducted to explore the diversity of genotypes for drought tolerance. The study was carried out at the Laboratory of Department of Botany and the Experimental area of Wheat section, Department of Plant Breeding and Genetics, Punjab Agricultural University, Ludhiana during two successive growing seasons of 2016-17 and 2017-18. To find out the diversity of genotypes for glaucousness, visual scoring was done at vegetative, anthesis and post-anthesis stages under irrigated condition. Accessorymorphological data i.e. plant height, tillers per meter row length, spikelets per spike and grain yield was recorded. After screening of the whole set of genotypes, thirty four genotypes were selected on the basis of their category for glaucousness score and evaluated under irrigated and rain-fed conditions. The genotypes with high glaucousness score were evaluated for epicuticular wax content in flag leaf, peduncle and ear at anthesis and post-anthesis stages. Accessory-morphological data i.e. plant height, tillers per meter row length, spikelets per spike, grains per spike, thousand grain weight, grain yield and harvest index was recorded. Based on the high epicuticular wax content of genotypes at post-anthesis stage under irrigated and rain-fed conditions, Gladius, PBW 771 and BWL 5233 can be regarded as water stress tolerant genotypes on the basis of spikelets per spike, grains per spike, thousand grain weight, grain yield, harvest index and drought tolerance indices. The identified genotypes can be included in the future breeding programmes for crop improvement in drought prone areas.ThesisItem Open Access Interactive effect of nitrogen, irrigation and tillage on maize (Zea mays L.) productivity(Punjab Agricultural University, Ludhiana, 2018) Raagjeet Kaur; Kahlon, M.S.Adoption of proper tillage-residue management along with fertilization and irrigation play an important role in influencing crop and water productivity. Tillage-residue management practices influence mechanical and water transmission characteristics of the soil besides influencing nitrogen (N) cycling and processes in soil. Therefore, an experiment was conducted on maize (cultivar PMH-1) and wheat (cultivar PBW 725) with three N levels i.e. N1 (90 kg N ha-1), N2 (120 kg N ha-1) and N3 (150 kg N ha-1) in main plots, four tillage-residue management practices i.e. conventional tillage (CT), conventional tillage with mulch (CTM), no-tillage with residue (NTR) and deep tillage (DT) in sub plots and two irrigation regimes {IW/PAN-E ratio 0.6 (I1) and 0.9 (I2) in sub-sub plots. The DT significantly increased biomass, thousand grain weight, grain yield, partial factor productivity and water productivity of maize by 25.9, 7.8, 23.2, 23.8 and 23.0 % and that of wheat by 51.6, 14.4, 17.4, 18.1 and 17.7 % respectively, over CT. The highest N level i.e. N3 significantly increased biomass, grain yield and water productivity by 25.9, 34.9 and 35.2 % in maize and by 51.6, 47.6 and 47.7% in wheat respectively, over N1. In maize, I2 significantly increased plant height, biomass and partial factor productivity over I1 by 3.0, 7.6 and 8.6 % respectively. Similar observations were recorded for wheat. The water productivity was found to be significantly decreased with increase in irrigation level, however, it was significantly higher under DT with N3 level than other treatments in both maize and wheat. The soil bulk density (Mg m-3) was found to be highest under NTR (1.73) and lowest under DT (1.62) at sub surface layer (15-30 cm). Significant differences due to tillage-residue practices were also reported in saturated hydraulic conductivity (cm hr-1) with highest value being in DT (5.1 and 4.0) and lowest under CT (3.1 and 2.2) at 0-7.5 and 7.5-15 cm soil depth, respectively. Soil aggregation was found to be significantly affected by tillage-residue management practices. Maximum mean weight diameter (0.68 mm) and water stable aggregates (48.4 %) were recorded in NTR. Significantly lowest mean value of penetration resistance (M Pa) was found in case of DT (1.3) and highest under CT (2.2). Higher volumetric soil water content and soil profile moisture storage was observed in NTR. For higher productivity of maize-wheat system, the DT along with N level 150 kg N ha-1 and irrigation regime of IW/CPE ratio 0.9 was found to be suitable practice for northwest India.ThesisItem Open Access Hormetic studies of 2,4-D in wheat (Triticum aestivum L.) and associated dicotyledonous weeds - Medicago denticulata Willd. and Rumex dentatus L.(Punjab Agricultural University, Ludhiana, 2018) Avneet Kaur; Navjyot KaurThe present study entitled, “Hormetic studies of 2,4-D in wheat (Triticum aestivum L.) and associated dicotyledonous weeds - Medicago denticulata Willd. and Rumex dentatus L..” was conducted to test the effect of low doses of 2,4-D on wheat and associated dicotyledonous weeds. Low concentrations of 2,4-D failed to accelerate either germination or seedling growth of Triticum aestivum and tested four weed species – Phalaris minor, Avena ludoviciana, Medicago denticulata and Rumex dentatus. The application of 2,4-D herbicide inhibited the seed germination and seedling growth of these weeds in a dose dependent manner with higher concentrations being more inhibitory. Foliar applied 2,4-D in range of 5-20 g ha-1 increased the chlorophyll content index (CCI) and chlorophyll fluorescence (Fv/Fm) values in wheat as compared to control and maximum value of CCI and Fv/Fm was recorded at 20 g/ha 2,4-D showing hormetic effect of 2,4-D at low doses upto flag-leaf stage of crop. Wheat yield and yield attributing parameters were not boosted significantly by low doses of 2,4-D ranging from 5 to 50 g ha-1. No significant difference between control and treated plants at harvest indicates that growth stimulation by low doses of 2,4-D was not sustained over time. The foliar application of 2,4-D at low concentrations ranging from 5-50 g ha-1 did not exert hormetic effects in R. dentatus and M. denticulata as application of different doses of 2,4-D led to a reduction in seed production potential of these weeds.ThesisItem Restricted Genetic diversity analysis using morphological and molecular markers in eggplant (Solanum melongena L.)(Punjab Agricultural University, Ludhiana, 2018) Amandeep Kaur; Nirmaljit KaurGenetic diversity for different morphological traits and molecular markers of 26 eggplant genotypes including 6 hybrids was conducted at Punjab Agricultural University, Ludhiana during 2016-2018. The genotypes were characterized on the basis of 34 morphological (21 quantitative and 13 qualitative) traits and 70 SSR markers. On the basis of different quantitative traits by using Mahalanobis D2 statistic, the eggplant genotypes were grouped into six clusters with the maximum genotypes in cluster I (13 genotypes) and minimum in cluster IV and VI (one genotype in each). The maximum inter-cluster distance in quantitative traits was in cluster IV and VI (1328.581) which indicated that the genotypes in these clusters were highly diverse from each other. The minimum inter-cluster distance was observed between cluster I and II (368.376). The intra-cluster distance was maximum in cluster III (267.497) with four genotypes. The intracluster distance for the clusters IV and VI was 0.00, because of single genotype in each of these clusters. On the basis of qualitative traits, the eggplant genotypes were grouped in six clusters and the inter-cluster distances varied between15.78 to 56.43. The maximum cluster distance was in cluster IV and VI (56.431) which indicated that the genotypes in cluster IV (93SN-22-1-1-2) and VI (P-67) were highly diverse from each other. The minimum cluster distance was in cluster III and VI (15.781). The intra-cluster distance for the clusters VI and V was 0.00, because of single genotype in each of these clusters. The intra-cluster distance was maximum in cluster II (12.716) with six genotypes. Forty polymorphic markers amplified, a total of 102 alleles with an average of 2.55 alleles per locus were observed. A maximum of five alleles were amplified by emi03K06 marker. Polymorphic information content (PIC) value ranged from 0.07 to 0.78 with an average of 0.50. The highest PIC value was recorded by emi03K06 (0.78) whereas, it was minimum in emf01L14 (0.07). UPGMA based (similarity coefficient) analysis classified the eggplant genotypes into 4 clusters. Cluster I was further divided into 3 groups (IA, IB and IC). Cluster II (SC-15-2) and IV (BH-2) consisted of one genotype in each cluster. Cluster III contained two genotypes (BL-216 and BR-109). The eggplant genotypes with desirable traits can be used for successful breeding programme.ThesisItem Open Access Photosynthetic traits and antioxidative enzymes under low light stress in Indian mustard (Brasica juncea L.) genotypes(Punjab Agricultural University, Ludhiana, 2018) Kirandeep Kaur; Sharma, PushpThe present investigation was carried out to assess the effect of low light stress on photosynthetic traits and antioxidative enzymes in Brassica juncea genotypes. Shading was done with nets from mid Dec. 2015 – mid Jan. 2016 which cuts 25-30% natural sunlight. Flower and fruit initiation took more number of days while flowering and fruiting duration declined with shading. PHR-1 took maximum days for flowering and siliqua initiation, PBR-357 for flowering completion, PHR2 for flowering duration, PBR-210 for siliquing completion and duration. Reproductive phase was shortened by 5.6 days whereas days to maturity were comparable under control and shaded treatments. At two stages of investigations (10 and 30 days after removal of nets) LAI and PAR significantly declined by 40, 12.6% and 43.4, 19.7% respectively however extinction coefficient (k) increased by 30.7% and 33% at two respective stages. Plant water status declined in terms of RWC by 1.9%, LWR by 16.6% along with SLW (16.6%), SLA (14.5%) and leaf traits to appreciable extent with shading removal after 10 days. Similar trend was recorded for these traits 30 days after removal of nets however, WSD increased from 9.3% to 34.2% at two stages with shading. Decline in SPAD values were comparable at two dates whereas Chl a, total Chl, Chl a/b and carotenoids were higher under control and declined under shading. Interestingly Chl b enhanced with shading at two stages. Antioxidative enzymes and MDA content increased whereas sugars and protein content decreased with shading at two stages of assay. Low light stress induced by shading had a profound effect on growth parameters, yield components and seed yield in studied genotypes with a mean reduction of 5.4% for plant height, 2.7% for length of main raceme and 1.2% for primary branches in PBR-210 whereas 0.5% for secondary branches in PBR-357. Differential response was registered with shading for nitrogen content, crude proteins, glucosinolates and oil content along with N-uptake. Declining trend with shading over control was witnessed in fatty acids profiling however oleic, linoleic and erucic acids did not vary much in PHR-2. PBR-422 suffered lesser reduction in seed yield followed by RLM-619 accompanied by lesser decline in the morpho-physiological traits and increased antioxidative enzymes.