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2012 - 20183
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Subject: Botany × Author: Amandeep Kaur × End date: 2022 ×
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    Genetic diversity analysis using morphological and molecular markers in eggplant (Solanum melongena L.)
    (Punjab Agricultural University, Ludhiana, 2018) Amandeep Kaur; Nirmaljit Kaur
    Genetic 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.
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    ThesisItemOpen Access
    Deciphering Morpho-physiological traits for drought tolerance of Iranian wheat (Triticum aestivum L.) landraces
    (Punjab Agricultural University, Ludhiana, 2018) Amandeep Kaur; Sarlach, R.S.
    The present research work on “Deciphering Morpho-physiological traits for drought tolerance of Iranian wheat (Triticum aestivum L.) landraces’’ was carried out to explore the genetic diversity of landraces for drought stress tolerance. The study was carried out at wheat laboratory and experimental area of Department of Plant Breeding and Genetics , Punjab Agricultural University, Ludhiana during two successive growing seasons of 2015-2016 and 2016-2017.To find water stress tolerance among Iranian landraces, they were subjected to different concentration of Polyethylene glycol (2%, 4%, 6%,8%,10%,14%, 16% and 18%). Among these different concentration14% PEG was found to be the suitable dose for screening, stress induced by using 14% PEG solution was best to highlight the differences in the set of germplasm.At16% and 18% most of the lines not germinated .After screening of whole set of Iranian landraces 27 landraces were selected on the basis of vigor index and evaluated under field conditions i.e. Irrigated, restricted irrigated and rain-fed conditions. The experiment was carried out in RBD design with two replications Drought environment was created by with holding of irrigation. Morpho-physiological data on plant height, tillers per meter row length, spikelet per spike, grains per spike grain yield, thousand grain weight, harvest index, chlorophyll content, stay green habit were recorded. On the basis of performance of Iranian lines under field conditions ,IWA 8600064, IWA 8600179 and PETTERSON ML68-10 considered as water stress tolerant on the basis of spikelet per spike, grains per spike thousand grain weight, grain yield and harvest index. The identified landraces can be included in future breeding programmes for the wheat improvement for drought prone areas.
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    Physiological basis of nitrogen use efficiency in maize (zea maysl.) at various rates of applied nitrogen
    (PAU, 2012) Amandeep Kaur; Bedi, Seema
    Field and laboratory experiments were conducted at Punjab Agricultural University, Ludhiana during kharifseason in the years 2009 and 2010 respectively to study the physiological basis of nitrogen use efficiency in maize (Zea mays L.) at various rates of applied nitrogen. Six maize genotypes (hybrids and their parents) i.e., long duration PMH1 (parents LM13, LM14) and short duration JH3459 (parents CM143, CM144) were raised under five nitrogen levels viz; recommended (RDN), RDN+25%, RDN+50%, RDN-25% and RDN-50% respectively. Various ecophysiological traits viz; leaf area, leaf area index (LAI), fraction of PAR intercepted by plants (FRI), intercepted photosynthetically active radiation (IPAR), radiation use efficiency (RUE) were significantly improved with the application of nitrogen at higher than the recommended rates in both long and short duration genotypes. Low nitrogen levels increased anthesissilking interval and shortened the duration of grain filling. It also caused a reduction in grain yield and its determinants mainly harvest index, 100-kernel weight, cob weight, above ground biomass, shelling percentage, cob length and diameter, number of kernel rows per cob and number of kernels per cob. The various physiological traits such as plant height, crop growth rate, relative growth rate, dry matter accumulation, root-shoot ratio etc. were significantly increased with the application of 25% and 50% higher nitrogen than the recommended. The applied nitrogendose also affected the content of various biochemical constituents (total soluble sugars, total soluble proteins, total starch content, chlorophyll content as well as the activity of various enzymes viz., nitrate reductase (NR), glutamine synthetase (GS), glutamate synthase (GOGAT) and PEP carboxylase). Path coefficient analysis showed that various traits such as RUE, LAI, FRI, IPAR, GS and NR activity had the maximum positivedirect contribution to grain yield in both set of maize genotypes (long and short duration). Therefore, these traits should be used as target traits to improve maize grain yield at both high and low nitrogen levels. The various quality parameters (starch, proteinand oil) in grains of both long and short duration genotypes were maximum in the treatment RDN+50%. Aminoacid content (total free amino-acids, tryptophan and methionine content) was significantly decreased with the decrease in nitrogen (RDN-25%; RDN-50%) than the recommended. In contrast, there was a decreasing pattern in nitrogen use efficiency (NUE), nitrogen remobilization efficiency (NRE) and nitrogen harvest index (NHI) values with increasing fertilizer rates in both long and short duration genotypes. Hybrids i.e. PMH 1 (long duration) and JH 3459 (short duration) were more responsive to variations in nitrogen supply than their female and male parents. Moreover, the high nitrogen use efficiency for hybrids (PMH1, JH3459) as compared to their parents (LM13, LM14 ; CM143, CM144) was associated with greater PAR interception during the growth period , high radiation use efficiency (RUE), more harvest index (HI), high photosynthetic capacity associated with increased acitivity of PEP carboxylase enzyme and high chlorophyll content in leaves, high nitrogen metabolic efficiency, increased activity of nitrogen metabolism enzymes (nitrate reductase, glutamine synthetase and glutamate synthase) leading to higher nitrogen harvest in dex. Keywords:GOGAT, GS, maize, nitrogen, NR, NUE, PAR, PEP carboxylase, RUE, yield