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ThesisItem Restricted Morpho-physiological responses of Chrysanthemum coronarium and Calendula officinalis to hyperaccumulation of cadmium(Punjab Agricultural University, Ludhiana, 2020) Singla, Himani; Jhanji, ShaliniThe present investigation entitled ―Morpho-Physiological responses of Chrysanthemum coronarium and Calendula officinalis to hyperaccumulation of cadmium‖ was conducted in the Department of Floriculture and Landscaping and Department of Botany, Punjab Agricultural University, Ludhiana during the year 2019-20. The seedlings of Chrysanthemum coronarium and Calendula officinalis were planted in pots filled with soil treated with different concentrations (0, 20, 40, 60, 80 and 100 ppm) of cadmium (Cd ) ,applied as Cd(NO3)2. Growth parameters viz. plant height, number of leaves, leaf area per plant, leaf dry weight, number of flowers, flower diameter, of both the ornamentals were affected with increase in Cd concentration but at 20 ppm there was no adverse effect on growth of Calendula. Cadmium retarded plant growth as dry weight of Chrysanthemum roots declined by 20%, stem by 31% and leaves by 14% under 100 ppm Cd application and the corresponding values for Calendula were 18, 28 and 14% respectively. With increase in Cd concentration, there was reduction in moisture content, relative water content and membrane integrity of leaves and petals of both plant species. Significant reduction in various biochemical parameters viz., total soluble sugars, total soluble proteins, chlorophyll and carotenoid content was also recorded with increase in Cd concentrations. There was increase in Cd content in roots, stem, leaves and flowers of both ornamentals, being higher in Calendula than Chrysanthemum. DTPA-extractable Cd in soil was decreased from equilibrium to budding to commercial harvest and decline being highest under 60 ppm, 45.75% in Calendula and 34% in Chrysanthemum showing greater Cd uptake by roots of Calendula and high mobility index (MI) from soil to root than Chrysanthemum whereas uptake was recorded to be more by stem of Chrysanthemum than Calendula due to its higher biomass. Both Calendula and Chrysanthemum showed Bio-concentration factor (BCF) and Translocation factor (TF) to be more than 1 whereas Enrichment factor (EF) and Remediation factor(RF) were more than 1 in both species but higher in Calendula than Chrysanthemum. Thus, besides commercial significance of Calendula and Chrysanthemum both ornamentals can be used for phytoremediation of Cd contaminated soils.ThesisItem Restricted Effect of fruit harvest stage and storage on quality and longevity of cucumber (Cucumis sativus L.) seeds(Punjab Agricultural University, Ludhiana, 2020) Pathania, Kartik; Navjyot KaurThe present investigation entitled “Effect of fruit harvest stage and storage on quality and longevity of cucumber (Cucumis sativus L.) seeds” was conducted during 2019 and 2020. The experiment was conducted in completely randomized design with two factors namely stages of fruit harvest and stages of in-situ storage duration of fruits. The fruits were harvested at 30, 40 and 50 days after anthesis (DAA) and seeds were extracted immediately and after 5, 10 and 15 days of fruit detachment from plants. Percentage of developed seeds, seed weight per fruit (g), 100 seed weight (g), membrane stability index, germination (%), seedling vigour index, speed of germination and storage reserves in seeds viz., starch, total soluble proteins and total amino acids were increased significantly with delay in stage of fruit harvest from 30 to 50 DAA and increased in-situ storage duration of fruits from 0 to 15 days. However, the number of undeveloped seeds, relative water content, mean germination time, total soluble sugars and oil content in seeds decreased with delay in stage of fruit harvest and increased insitu storage duration of fruits from 0 to 15 days during both the years. Total soluble sugars and free amino acids in fruit pulp increased while total soluble proteins and starch content in fruit pulp decreased with delay in stage of fruit harvest and increased in-situ storage duration of fruits during both the years. Seeds extracted from different treatments were stored for 8 months and tested for different parameters at bi-monthly intervals. After 8 months of seed storage, best seed quality parameters were obtained when seeds were extracted from fruits harvested at 50 DAA with in-situ storage of 10 days. Based on two years data, it can be concluded that to obtain maximum seed yield, quality and storability of cucumber seeds, fruits must be harvested at 50 DAA with at least in-situ storage of 10 days.ThesisItem Open Access Effect of different green shade net houses on growth and biochemical components of various Ocimum spp.(Punjab Agricultural University, Ludhiana, 2020) Aayushi; Sharma, RajniThe effect of different green shade net houses on the growth and biochemical constituents were recorded during the present investigation on four different Ocimum spp. (O. tenuiflorum, O. sanctum, O. basilicum and O. gratissimum). The plants were grown under five different shading intensities viz- 35%, 50%, 75%, 90% and open (no net condition) as control. Growth parameters like number of branches, number of leaves, total fresh weight, total dry weight, leaf dry weight, shoot dry weight were recorded to be higher in 35% shading intensity than control and other shading intensities whereas stem diameter and root length were higher in control in comparison to other shading intensities. However, parameters like plant height, internodal length and leaf area were recorded higher in 90% shading intensity than in control. All growth parameters except plant height, internodal length and leaf area were found to be suppressed as the shading intensity was increased beyond 50%. The requirement of moderate light intensity for better growth and development has been reflected in maximum growth parameters. Variable response was observed for biochemical parameters in different shading intensities. However, the trend was same for all species. Biochemical parameters like total carotenoid content, total sugars, reducing and soluble protein were recorded maximum in control i.e. under full sunlight followed closely by 35% shading intensity while 90% shading intensity recorded highest chlorophyll a, chlorophyll b and total chlorophyll content. Total phenols and flavonoids were recorded to be highest in control (no net conditions) followed closely by 35% shading intensity while alkaloids and terpenoids were recorded to be highest in 35% shading intensity followed closely by control. However, biochemical parameters were influenced but phytochemical compounds like alkaloids and terpenoids recorded increase under 35% shading intensity which contribute to its medicinal properties. Therefore, in present investigation, Ocimum spp. performs better in 35% shading intensity than other shading intensities and control.ThesisItem Open Access Effect of glycine betaine and proline on seed germination and seedling growth of oat (Avena sativa L.) under salt stress(Punjab Agricultural University, Ludhiana, 2020) Makkar, Astha; Gupta, NamrataIn present investigation, seeds of oats (Avena sativa L.) were subjected to different concentrations of salt stress (25mM, 50mM, 75mM 100mM) in OL-1896 and OL-1962 genotypes to study the effects of salinity on physiological (seed germination, seedling length, biomass, seed vigour and speed of germination) and biochemical parameters (total soluble sugars, proteins, MDA and activities of different antioxidant enzymes viz SOD, POX and CAT). Physiological parameters decreased with increasing salinity level whereas out of biochemical parameters; total soluble sugars, SOD, POX and MDA activity increased and total soluble proteins and CAT decreased. From the above stress levels used, two stress levels i.e. 50mM and 75mM were selected and seeds were treated with different concentrations of proline (5mM and 10mM) and glycine betaine (10mM and 20mM) to study their influence on physiological as well as biological parameters under salt stress conditions. The results showed that the seeds treatments (PRO 5mM, 10mM and GB 10mM, 20mM) improved the activity of physiological and biochemical parameters and reduced the harmful effects of salt stress in both genotypes of oats. Genotype OL-1896 was comparatively more tolerant to salt stress. Also, proline 10mM and glycine betaine 20mM was found to be more effective than proline 5mM and glycine betaine 10mM. Thus, the results suggest that exogenous application of proline and glycine betaine increased salt tolerance in oat seedlings.ThesisItem Open Access Effect of priming on enhancing storability of brinjal (Solanum melongena L.) seeds(Punjab Agricultural University, Ludhiana, 2020) Japneet Kaur; Bedi, SeemaThe present study was conducted on brinjal (Solanum melongena L.) seeds var. Punjab nagina. The quality of brinjal seeds in-terms of vigour and viability severely declines as a result of natural ageing during storage between harvesting and next sowing season. The objective of this study was to evaluate the effect of various priming treatments on the quality and storability of brinjal seeds. The freshly harvested seed was divided into two lots. One of these seed lots was subjected to accelerated ageing to obtain low vigour seed and the other lot was considered to be high vigour. The high and low vigour seeds were primed with KNO3 (1%), GA3 (100ppm), KH2PO4 (0.1M), PEG 6000 (30%) and H2O for 12 hours at 25oC. Thereafter, the seeds were stored in moisture impervious bags for 12 months in a refrigerator (4C). The objective was to observe whether the priming treatments improve the seed vigour and also retain the advantages obtained from priming during storage. The seeds were drawn at three-monthly intervals, viz. zero, three, six, nine and twelve months of storage. Physiological (germination percentage, speed of germination, mean days to germination, seedling length, root length, shoot length, seedling dry weight and seedling vigour index) and biochemical (Total soluble sugars, total soluble proteins, α-amylase activity and membrane stability index, starch content, total free aminoacids) observations were recorded. With an increase in storage duration, a decline in physiological and biochemical aspects of seed quality was observed in both high and low vigour seeds. All the priming treatments improved the germination related parameters in both high and low vigour seeds over control but the extent of improvement varied. Seed priming with GA3 (100ppm) followed by priming with KNO3 (1%) were found to be the best treatments for both high and low vigour seeds even after storage for 12 months.ThesisItem Open Access Effect of shading on the performance of Indian mustard (Brassica juncea L. Czern and Coss) genotypes(Punjab Agricultural University, Ludhiana, 2020) Sonika; Sharma, PushpThe present investigation was carried out to assess the effect of shading on the performance of Brassica juncea genotypes. Shading was done with nets for one month commencing from mid December 2018 – mid January 2019 which cuts 25-30% of natural sunlight. Flower and fruit initiation took more number of days while flowering and fruiting duration were reduced with shading. Differential behaviour with shading was reported for reproductive phase and days to maturity. PHR-126 took maximum days for flowering and siliqua initiation, PBR-396 for flowering completion and duration, PBR-561 for siliquing completion and duration. Reproductive phase was shortened by 2.3 days whereas days to maturity were comparable under control and shaded treatments. Chl a (23.8%), carotenoids (19.1%) and SPAD (8.5%) were significantly reduced after 10 days of shading and 31.5%, 27.9% and 6.7% after 30 days of imposed low light stress. However, chlorophyll b exhibited an increase of 16.7% and 37.5%. The photochemical efficiency of PSII was reduced by 2.8% under shade. Leaf traits like, leaf area, SLA, SLW, LWR and RWC declined under shade while RSD and WSD increased at both the studied stages. Leaf and stem anatomy was affected by low light stress as the thickness of tissues was reduced in comparison to control in all the studied genotypes. Kranti, PBR-450, PBR-396 and PBR-464 were registered for higher anatomical characteristics with minimum decline under low light stress as compared to control. Stomatal responsiveness to low light revealed smaller size of stomata with lower stomatal frequency and index on both the abaxial and adaxial leaf surface as compared to control. Antioxidative enzymes and MDA content increased whereas sugars and protein content decreased with shading assayed at two stages. Low light stress had a profound effect on growth parameters, yield components and seed yield in studied genotypes with a minimum reduction of 1.1% for plant height and 1.8% for primary branches in Varuna, 0.5% for length of main raceme in PBR-396 whereas 2.1% for secondary branches in PBR-561. PBR-396 suffered lesser reduction in seed yield followed by Kranti accompanied by lesser decline in the morphophysiological traits and increased antioxidative enzymes. Seed yield had positive association with phenological traits except flowering duration under low light stress. Stomatal length and size were significantly associated with seed yield under both stressed and non-stressed condition. Kranti, PBR-396 and PBR-464 were promising cultivars under low light stress with seed yield reduction of ≤ 20%, SSI (≤1.0), STI (≥0.5) and YSI (≥0.70).ThesisItem Open Access Physiological and biochemical basis of high temperature stress tolerance and its amelioration in bell pepper (Capsicum annuum L. var. grossum)(Punjab Agricultural University, Ludhiana, 2020) Tejinder Preet; Ghai, NavitaThe present investigation was carried out to evaluate the role of plant growth regulators viz. Salicylic acid (SA) and 24-epibrassinolide (EBR) on the physiological and biochemical parameters of bell pepper (Capsicum annuum L.). Two cultivars of bell pepper viz. hybrid Indra and variety Royal Wonder were selected for the study along with Punjab Sindhuri (hot pepper) used as a tolerant check for heat tolerance. Three concentration of each growth regulator, SA (0.10 mM, 0.20 mM and 0.50 mM) and EBR (0.05 µM, 0.10 µM and 0.20 µM) were applied in the form of foliar spray to both the cultivars at three growth stages, vegetative bud stage (30 DAT), reproductive stage (60 DAT) and post-reproductive stage (90 DAT). All the concentrations of PGRs were effective in imparting thermotolerance in terms of improved growth parameters (plant height, plant spread and leaf area), membrane thermostability, photosynthetic parameters (total chlorophyll content, carotenoid content and hill reaction activity), levels of total soluble sugars, starch, proteins, proline, enhanced antioxidant system (CAT, APX, POX, SOD and GR), fruit parameters (fruit length, fruit width, pericarp thickness and fruit chlorophyll). Application of SA and EBR resulted in reduced lipid peroxidation in leaf tissue and cellulase activity in pedicel of flowers, causing more retention of flowers, increased pollen viability and fruit set percent even at high temperature ultimately resulting in improved yield. Appearance of some new bands during SDS-PAGE of proteins in treated plants pointed towards the foundation of HSPs which helped the plants to survive under stressful conditions. Foliar spray of 0.10 µM EBR in hybrid Indra and 0.20 mM in variety Royal Wonder done at reproductive stage (60 DAT) and vegetative bud stage (30 DAT), respectively, were most effective in ameliorating the effects of high temperature stress.ThesisItem Open Access Characterization of morpho-physiological and biochemical trait for heat tolerance in Indian mustard (Brassica juncea L. Czern. & Coss)(Punjab Agricultural University, Ludhiana, 2020) Priya; Sharma, PushpThe present investigation “Characterization of morpho-physiological and biochemical trait for heat tolerance in Indian mustard (Brassica juncea L. Czern. & Coss)” was conducted in timely and late planted set of forty nine advanced breeding genotypes in two rabi seasons (2016-17 and 2017-18) at Punjab Agricultural University, Ludhiana and Dr. JC Bakhshi, Regional Research Station, Abohar which were further evaluated in the temperature gradient tunnels (TGT), Department of Climate Change and Agricultural Meteorology, Punjab Agricultural University, Ludhiana with the objective to standardize the screening techniques for heat tolerance based on morpho-physiological, biochemical and yield traits. Experiments were laid in factorial randomized block design. High temperature experienced by late planting led to reduced phenological duration at both locations while genotypes attained late maturity in TGT (13 days). Physiological traits like chlorophyll content, SPAD value, LAI and PAR (%) increased from vegetative to flowering stage followed by decline at siliquing stage whereas chlorophyll and SPAD value increased in TGT at flowering and siliquing stage. Lower CTD, decline in RWC (23.0%), LWR (12.0%) and MS (36.3%) while increase in WSD (16.8%), RSD (15.4%) and MI (18.1%) under delayed sowing. The high demand for utilizing stem reserve but lower accumulation and translocation of photoassimlates led to the imbalance between source to sink translocation in delayed planting however up regulation of antioxidative enzymes and non enzymatic antioxidative biomolecules imparted thermo tolerance. Positive association of seed yield existed at two locations with phenological durations, BY, HTI and HSI. Selection criteria of seed yield reduction (<30%), lower HSI (≤1) and higher HTI (≥1), over the years at two locations rated PCR-3, CSR-158, HLM-4113-2, ELM-38, CSR-1163, JMG-244 and CM-21-16promising. Three genotypes PCR-3, ELM-38, CSR-1163 were identified heat tolerant at two locations and in temperature gradient tunnels.ThesisItem Open Access Evaluation of Elymus semicostatus germplasm from lahaul valley as potential donor for wheat improvement(Punjab Agricultural University, Ludhiana, 2020) Antul Kumar; Sharma, RajniThe present investigation entitled “Evaluation of Elymus semicostatus germplasm from Lahaul valley as potential donor for wheat improvement’’ was carried out to evaluate the in depth botanical characterization, their physiological responses in different water environments and hybridization attempts to mobilize the useful traits into wheat. The plant material was collected from Lahaul valley (Lahaul-Spiti, HP) and its adjoining regions. The field experiments were conducted at the research farm of Wheat section, Department of Plant Breeding and Genetics, Punjab Agricultural University, Ludhiana. The E. semicostatus showed morphological resemblance with three other members of the genus Elymus viz: E. longiaristatus, E. repens and E. dahuricus. Forty distinguishing characters were marked for each species. The E. semicostatus showed morphological adaptation for drought tolerance such as dense pubescence, awn length and colour, leaf waxiness and pigmentation on other plant parts. The germplasm set was narrowed down to 34 accessions on the basis of their intra-specific variation during field evaluation. Selected 34 accessions set was evaluated for drought tolerance traits under field conditions. Vernalization treatment for 4-6 weeks at 4-8˚C and 8hr photoperiod was provided to germinated seedlings in December and January for about 6-7 hours to synchronize flowering with hexaploid wheats. The drought conditions were created by withholding irrigation (rainfed), regular recommended irrigation and restricted irrigation (1-2 times after transplantation). The morpho-physiological traits such as plant height, flowering days, spike length, leaf area, tiller numbers, chlorophyll contents at different stages and relative water content were observed at anthesis. For morpho-physiological parameters, the NBPAU28 showed maximum plant height (133cm), spike length (25.67 cm), tiller number (33.17) and leaf area (30.32cm). The accessions NBPAU7, NBPAU13, NBPAU14 and NBPAU28 were best for plant height, spike length, leaf area, whereas NBPAU1, NBPAU6, NBPAU15 and NBPAU27 performed well under drought conditions. The chlorophyll content was significantly increased during anthesis in all accessions and then declined, but it maintains low chlorophyll content upto harvesting stage. In an attempt to cross the species with hexaploid wheat, embryo rescue was attempted. A total of 991 caryopses were obtained from the crosses of three consecutive seasons from 2017 to 2018. Only 20 hybrid plants could be established on account of the desiccating conditions at PAU, which probably contributed to low survival rate. The surviving hybrid plants never reached booting stage at PAU, Ludhiana. The E. semicostatus can be a potential donor for the drought tolerance traits and more detailed studies on overcoming pre and post fertilization barriers need to be done for introgressing useful traits into wheat cultivars for wheat improvement.
