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Professor Jayashankar Telangana State Agricultural University, Hyderabad (Telangana State)
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ThesisItem Open Access ENRICHMENT OF β-CAROTENE IN QUALITY PROTEIN MAIZE INBREDS THROUGH MOLECULAR BREEDING(Professor Jayashankar Telangana State Agricultural University, 2016) SAGARE DEEPTI BABURAO; SOKKA REDDY, S.Vitamin A deficiency (VAD), a primary cause of blindness afflicts over 250 million people across the globe. Development of micronutrient enriched staple plant foods through “biofortification” holds significant promise in alleviating VAD due to its cost effectiveness and sustainability. Maize posseses natural variations for provitamin A carotenoids. Enhancement of kernel provitamin A carotenoids in QPM genetic background is of greater value as compared to improvement in normal maize. Thus, the present investigation was carried out to analyse the genetic variability for provitamin A carotenoids to identify promising β-carotene donor and enrichment of β-carotene in QPM through molecular breeding. In the study of genetic variability for provitamin A, four maize inbreds viz., MGU23379, MGU23207, CM150 and BAJIM12-11 were found to contain favorable allele i.e. allele1 of crtRB1-3’TE and one maize inbred BML13 was found to possess favorable allele i.e. allele4 of lcyE-5’TE. Maize inbred MGU23379 was found to contain high amount of β-carotene (6.14µg/g) and was used as promising β-carotene donor. Among the QPM inbreds, CB6-36 and CB7-28 were found to be suitable recipient parents and named them as, CBML6 and CBML7, respectively. There was distinct polymorphism between donor and recurrent parents for crtRB1-3’TE. Eighty two SSRs were polymorphic between donor and CBML6 whereas, 161 SSR markers were polymorphic between donor and CBML7. In the conversion programme F1, BC1F1, BC2F1, BC2F2 and BC2F3 materials were generated. In each generation foreground selection with crtRB1-3’TE and umc1066 was carried out. Whereas, in BC1F1 and BC2F1 generation recombinant and background selection was carried out. RPG varied from 60.93% to 83.22% in BC1F1 populations and from 87.98% to 93.25% in BC2F1 populations. In both BC2F2 populations individuals with favorable allele in homozygous dominant condition were subjected to plant phenotyping. In converted CBML6 (PVCBML6), stem anthocyanin pigmentation was found to be reduced than the original QPM line. Also, the silk color was dark pink in original QPM line which was changed to light pink in PVCBML6. In converted 18 CBML7 (PVCBML7), tassel density was found to more spare and tassel was more erect than original QPM line. Silk color was changed to light pink in PVCBML7, which was pure white in original QPM line. Tryptophan content varied from 0.882% to 0.899% and 0.832% to 0.849% in PVCBML6 and PVCBML7 seeds, respectively. PVCBML6 seeds derived from individuals P6-3 and P6-193 were found with higher β-carotene content (6.25µg/g) whereas, PVCBML7 derived seeds of P7-31 were found with higher β-carotene content (6.80µg/g). The normal and converted lines were significant for all the phenotypic characters except for β-carotene content. The β-carotene content in converted inbreds was significantly higher than that of normal line and it was on par with the donor. These converted inbreds can be used for reconstitution of DHM117 maize hybrid rich in tryptophan, lysine and β-carotene. Converted lines also provides an ideal platform for stacking number of nutritionally important traits such as enhanced Fe, Zn, vitamin E, folate, ascorbic acids and low phytate. Key words: QPM, opqaue2, crtRB1-3’TE, β-carotene, provitaminA, recurrent parent genome, molecular breeding.ThesisItem Open Access CONVERSION OF PARENTAL LINES OF DHM119 MAIZE HYBRID INTO QPM VERSION EMPLOYING MARKER ASSISTED SELECTION(Professor Jayashankar Telangana State Agricultural University, 201) PRASHANT SHETTI; SOKKA REDDY, S.Enrichment of nutritional quality in maize has become essential in the malnourished population of the world. Several breeding efforts were initiated earlier to develop QPM hybrids and recently marker assisted selection is the most feasible way of developing QPM hybrids in short time. The present investigation deals with conversion of elite normal maize inbred lines BML2 and BML15 (parental lines of DHM119 maize hybrid) into QPM lines using marker assisted selection. Breeding efforts have led to the successful development of QPM cultivars and to improve the efficiency of QPM breeding, the utility of three simple sequence repeats (SSR) markers viz. umc1066, phi057 and phi112 were used in selection and introgression of the opaqaue2 gene. Polymorphism was detected between recipient parents (BML2 and BML15) and donor parent (CML142) with phi057 SSR marker. Foreground selection was carried out in each generation using opaque2 specific marker phi057. Recombinant selection was done using flanking markers to minimize the linkage drag and background selection was carried out in BC1F1 and BC2F1 generations to recover the recurrent parent genome (RPG) using genomic polymorphic SSR markers distributed across the genome. In BC2F1 the recovery of recurrent parent ranged between 90 to 93% and the plants with highest recovery were selfed to generate advanced generations (BC2F2 and BC2F3). Kernels were screened for endosperm hardness using light box and kernels showing less than 25% opacity were selected and further forwarded. Rigorous phenotyping was done for various plant characters and tryptophan was estimated using colorimetric method. Tryptophan content varied from 0.89% to 0.96% in converted lines of BML2 and 0.89% to 0.98% in converted lines of BML15. These normal looking converted inbreds named as CBML2 and CBML15 can be further used for reconstitution of the DHM119 maize hybrid. Key words: QPM- Quality protein maize, opqaue2, tryptophan, recurrent parent genomeThesisItem Open Access Marker Assisted Selection For Convertion Of Elite Maize Inbreds Into Hqpml Line With High Lysine And Trytophan(APAU ; Hyderabad, 2012) Krishna Motukuri S R