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20142
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Subject: Genetics and Plant Breeding × End date: 2014 × Start date: 2010 × Type: Thesis × Thesis Type: M.Sc ×
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    ThesisItemOpen Access
    Response of poplar clones to different soil types and growth regulator at nursery stage
    (Punjab Agricultural University, Ludhiana, 2014) Mitu Bala; Avtar Singh
    In present investigation the response of two types of soils (Sandy loam and Sandy clay loam soil) and foliar application of growth regulator i.e. Triacontanol at three levels (0ppm, 3ppm, 5ppm) was investigated on nine poplar clones (PL-1, PL-2, PL-3, PL-4, PL-5, PL-6, PL-7, L47/88, L-48/89) at nursery stage, conducted at Research farm area of department of Forestry and Natural Resources, Punjab Agricultural University, Ludhiana. Various attributes like growth characteristics, physiological parameters and nutrient content in leaves were recorded at different interval of growth. The results of the study revealed that Triacontanol showed non significant and soil types showed significant results for morphological characters Viz. Plant height, collar diameter, no. of branches/plant, no. of leaves/plant, leaf area. Sandy clay loam soil showed good response than sandy loam soil for all morphological characters. For physiological characters like chlorophyll content, soil types showed non significant results and growth regulator showed significant results. Triacontanol at 5ppm concentration showed higher chlorophyll content during July and October 2013 by 30.88 and 36.21 SPAD units, respectively. For nutrient content analysis like nitrogen, phosphorus and potassium in leaves of poplar clones, growth regulator and different soil types showed significant results. After critical analysis it was concluded that PL-7, PL-4, PL-2 and PL-1 were better clones among all other clones studied for morphological characters. PL-1, PL-4 and PL-7 showed higher growth characters in sandy loam soil and PL-1, PL-5 and PL-7 clones in sandy clay loam soil.
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    ThesisItemOpen Access
    Phenotypic evaluation and molecular profiling of Brassica juncea (L.) lines carrying introgressions from Erucastrum abyssinicum
    (Punjab Agricultural University, Ludhiana, 2014) Shruti; Atri, Chhaya
    Introgression lines (ILs), created in Brassica juncea, following hybridization with Erucastrum abyssinicum were studied to catalogue their genetic diversity and crop performance under stressed ecologies. Molecular data generated following amplification with 72 SSR markers (35 (A genome) and 37 (B genome)) suggested the occurrence of high genetic diversity. ILs like JA-85, JA-128, JA-77, JA-30, JA-72, JA-96, JA-196, JA-95, JA-75 fell in Cluster 1 along with E. abyssinicum and were amongst those lines that carried a very large chunk of genomic information from the wild donor species. Graphical genotyping revealed that percent introgression varied from 12.5% to 40% with maximum introgression in JA-30, followed by other ILs like JA-85 (39.9%), JA- 53 (38.3%), JA-128 (37.4%), JA-75 (37.4%), JA-77 (36%), JA-96 (35.9%), JA-95 (35.1%), JA-72 (34.9%), JA-196 (34.1%), JA-245 (33.7%). Least introgression from the donor parent was recorded in JA-24 (12.5%). On the whole, maximum introgression was seen in chromosome 3 of ‘B’ genome which had 43.2 percent introgression from the donor parent. Morphological evaluation helped to identify useful ILs for earliness and components associated with crop productivity. Some of the ILs like JA-344 (number of primary branches), JA-92 (number of siliqua on main shoot), JA- 42 (siliqua length), JA-159 and JA-235 (seeds per pod), JA-192 (seed yield) performed equally well in both the environments. Grain yield was positively associated with flowering, plant height, leaf area index etc. which indicated that higher yield can be achieved by bringing changes in these parameters. GG Biplot analysis also confirmed a high level of variation for all the traits studied. Morphological data for test characters was also used to generate Euclidean distance graphs based on Mahalanobis D2 analysis and the ILs were clustered in 10 groups. The growing unpredictability of climate requires breeding of cultivars adapted to broad environments. Three ILs namely JA-59, JA-65, JA-240 were able to tolerate high temperature while 16 ILs viz. JA-22, JA-31, JA-35, JA-38, JA-45, JA-65, JA-127, JA-147, JA-149, JA-174, JA-193, JA-233, JA-331, JA-343, JA-352 and JA-36 could tolerate low temperature stress during flowering. These ILs can further be used in future breeding programmes suited for the development of varieties for stressed ecologies.