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20133
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Subject: Plant Breeding and Genetics × End date: 2013 × Start date: 2010 × Thesis Type: Ph.D ×
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    MOLECULAR CHARACTERIZATION OF Triticum durum – Aegilops speltoides INTROGRESSION LINES AND EVALUATION FOR THERMO–TOLERANCE AND ITS COMPONENTS
    (PAU Ludhiana, 2013) Zewdu Teshome; Parveen, Chhuneja
    Backcross introgression lines (BILs) developed from crosses of Triticum durum –Aegilops speltoides were used to identify quantitative trait loci (QTLs) associated with heat tolerance.Three hundred lines in the first season and 100 selected lines in two consecutive cropping seasons were grown under normal sown and late sown conditions. Membrane thermostability, chlorophyll content (CH), canopy temperature and triphenyl tetrazolium chloride (TTC) tests have been used for identifying genetic variability within genotypes.Yield and yield related traits were also recorded. In all the traits variations between BILs in both normal sown and late sown conditions have been observed. Early maturity, shorter height and reduced tillering were recorded in late sown conditions which could be due to terminal heat stress. Out of 386 markers tested, 76 markers (19.7%) showed polymorphism between the parental lines. These polymorphic markers were used to genotype 100 selected BILs. Graphical genotyping showed introgressed regions in all 14 chromosomes of the recipient parent with overall 14.2% introgression.Single marker analysis (SMA) revealed that six markers (Xgwm293, Xgwm565, Xgwm148, Xwmc269, Xgwm299 and Xwmc603) were significantly associated with spikelets/spike at LOD values ranging from 6.1-10.3 and phenotypic contribution of 18.5-44.3%.Similarly, markers Xgwm293,Xwmc269, Xgwm565, Xgwm471, Xgwm148, Xgwm299, Xwmc603, Xwmc31, Xcfd6 and Xcfa2278 were linked to thousand grain weight. One marker Xcfd60 revealed association to TTC in normal sown BILs with LOD value of 3.1 and PVE of 16.1%. Four markers Xgwm293,Xgwm148, Xcfd60 and Xwmc269 showed linkage with CH with varying LOD score and PVE%. SMA also identified eight markers (Xgwm293, Xgwm565, Xgwm471, Xgwm148, Xgwm299, Xwmc603, Xcfd6 and Xwmc269) linked to days to flowering and four markers viz, Xgwm293, Xgwm471, Xgwm299 and Xwmc603 showed association to days to maturity with LOD value higher than the threshold. Plant height was also linked to four marker loci (Xgwm471, Xgwm148, Xgwm565 and Xwmc603) in average environment and stay green trait was linked to Xgwm148, Xwmc269, Xgwm471 and Xwmc269 with LOD score in the range of2.6 -3.4 and PVE of 12.6-15.9%. Additive QTL analysis identified that most of the traits were contributed from the donor parent and a number of markers identified in SMA were validated in additive QTL analysis also.
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    ThesisItemOpen Access
    Effect of alien cytoplasms on heterosis and combining ability of yield, quality and water use efficiency traits in sunflower (Helianthus annuus L.)
    (PAU, 2013) Tyagi, Vikrant; Dhillon, S K
    The present investigation was undertaken in the Department of Plant Breeding & Genetics, Punjab Agricultural University, Ludhiana during the years 2011 and 2012 to study the effect of alien cytoplasms on heterosis and combining ability of yield, quality and water use efficiency traits in sunflower (Helianthus annuus L). Analysis of variance for morphological, physiological and quality traits revealed significant differences due to genotypes and environments (irrigation regimes) for all the characters. Among sources E002-91A recorded a substantial increase in plant height, head diameter, seed yield and harvest index under stress environment, indicating its suitability for developing water use efficient hybrids. The D 2 analysis revealed a lot of diversity between cms analogues. Euclidean distance values indicated the uniqueness of ARG-3A under stress environment. For seed yield and its component traits E002-91A, ARG-3A, ARG-6A and RCR-8297 were good combiners under both the environments while PRUN-29A and CMS-XA under stress environment. The role of female parent was more in expression of all the traits as compared to male parents. The hybrid s CMS-XA x P100R, ARG-2A x P100R, ARG-6A x P69R, DV-10A x P100R, PRUN-29A x RCR-8297, 234A x P69R and 38A x P124R were identified as best specific combiners for seed yield and E002-91A x P124R, E002-91A x P100R, ARG-3A x RCR-8297, ARG-6A x P124R, DV-10A x P69R, PRUN-29A x P100R, 40A x RCR-8297, 40A x P124R for oil content. For seed yield maximum standard heterosis over check PSH-996 was recorded as 24.72 per cent for 40A x P69R (under normal environment) and 60.7 per cent for PRUN -29A x P69R (under stress environment). It is pertinent to mention here that all the sources significantly differed from PET-1 source with respect to seed yield per plant under both the environments and this effect was in positive direction. The sources ARG-3A and DV-10A had significant effect on heterosis for 100 seed weight under stress environment. Similarly for seed yield none of the sources recorded significant effect on heterosis under normal environment while in stress environment all the sources except ARG-2A and ARG-6A had positive effect on heterosis. Seed yield recorded significant positive association with plant height (0.301), highly significant correlation with leaf water potential (0.417) and biological yield (0.372) under normal environment. A total of 11 hybrids giving stable performance over normal and stress environments have been identified for seed yield. The genotypes with stay green trait at maturity were identified under both the environments. Drought susceptibility index (DSI) studies revealed that few genotypes recorded stable performance under both the environments with respect to seed yield having DSI values near to zero.
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    ThesisItemOpen Access
    Improvement of rice variety PAU 201 for aleurone colour and bacterial blight resistance using Marker Assisted Selection
    (PAU, 2013) Prem Kumar A; Gill, M.S.
    In Punjab, Rice variety PAU 201 was released for cultivation in the year 2007. Within two years this variety occupied 25% of total area under rice because of its high yield. It gives good yield under average conditions. However, recently this variety faced problems because of red aleurone colour, susceptibility to new evolved pathotypes of bacterial blight and low amylose content. During 2010, crosses were attempted between PAU 201 and RYT 3148 to improve the characters of PAU 201 with the help of molecular markers. The F1 plants were backcrossed with recipient parent and BC 1 F 1 seeds were generated. In 2011, marker-assisted foreground selection for first gene rc7 was analyzed on 270 BC 1 F 1 plants, 97 plants showed positive result for this gene in heterozygous condition. For second target gene (Xa21), 23 plants were found to be heterozygous for Xa21 and the desirable plants were backcrossed to recurrent to generate BC2 F 1 seeds. For third gene (wx), 10 plants out of 23 were recorded for the presence of three genes (rc7, Xa21 and wx) while 13 plants had two target genes (rc7 and Xa21). BC2 F 1 seeds were sown in kharif 2012, 371 out of 669 plants were heterozygous for rc7 gene. Among 371 BC 2 F 1 plants, 231 plants were selected which looked similar to PAU 201 in terms of agro-morphological characters. Out of these, 80 plants were found positive for Xa21 and 25 plants out of 80 plants were identified to be heterozygous for RM190. So, on the basis of analysis of three genes, 25 plants were identified to the presence of the target genes. In case of two gene category, 118 plants out of 778 were selected based on morphological characters which resemble to PAU 201. During parental polymorphic survey, 69 polymorphic markers (19.8%) were identified out of 348 between parents. Four and six polymorphic markers in carrier chromosomes 7 and 11 were applied on selected plants to find out the recovery percentage of recurrent parent. The recovery percentage of selected plants varied from 50-75% in carrier chromosomes 7 and 11. Based on GGT results, some plants were observed as heterozygous condition with retain segments from the recurrent parent, while heterozygosity was observed at all loci in the remaining plants for carrier chromosomes 7 and 11. Plants (24-12-43, 24-15-5, 24-18-8, 24-18-44, 24-78-54, 24-78-58, 24-200-17,24-200-18, 24-200-19, 24-200-24, 24-200-47, 24-200-69, 24-200-70, 24-200-71 and 24-200-75) carried three target genes with recurrent parent genome to the extent of 75.0% in carrier chromosomes along with grain size and shape similar to parents