Production of doubled haploids in rice (Oryza sativa L.) through anther culture and wide crosses and their molecular characterization
| dc.contributor.advisor | Gill, R.S. | |
| dc.contributor.author | Saundarya Kumari | |
| dc.date.accessioned | 2019-11-11T04:20:09Z | |
| dc.date.available | 2019-11-11T04:20:09Z | |
| dc.date.issued | 2019 | |
| dc.description.abstract | The doubled haploidy is one of the fundamental tools of plant breeding which provides the fastest way to accelerate plant breeding and develop homozygous lines in the shortest possible time. The F4/F5 population of japonica x indica derived cross (Dubraj x IR 75862-206-2-8-3-B.B.B.) was used for the production of doubled haploids through anther culture for two crop seasons. Approximately 74,834 and 88,100 anthers from 87 and 21 lines respectively were cultured during kharif 2016 and 2017 crop seasons. Standard N6 medium supplemented with 2, 4-D (2.0 mgL-1) + BAP (0.5 mgL-1) +Sucrose (3 %) was used. Callus induction frequencies (CIF) varying from 0.07405 to 8.235 and 0 to 8.835 respectively were obtained during kharif 2016 and 2017 and upon transfer of 2-3 mm calli on regeneration media with varying compositions the regeneration frequencies varying from 0 to 100 and 0-35 per cent respectively were obtained. Delayed callus response initiating 90 days after culturing was observed during both the culturing seasons. All the regenerated shoots were albinos and no green plantlets could be obtained, which may be due to genotypic specificity leading to delayed callusing. The parental lines also had poor response towards anther culturability with CIF of 0.00, 0.020 and 0.064, 0.04 for Dubraj and IR 75862-206-2-8-3-B.B.B. respectively during kharif 2016 and 2017. Anther culture of a different set of material belonging to 41 crosses combinations of Basmati and non basmati genotypes during kharif 2018 though in general, gave low callus induction frequencies but high frequency of plant regeneration varying from 2.56 to 100 per cent was observed. Contrary to previous seasons results the callus initiation started 30 days after culturing and about 16 putative doubled haploid plants were generated. Studies on identification of genomic regions associated with anther culture response by using twenty two polymorphic SSR markers revealed random distribution of indica and japonica type alleles in callus as well as callus responsive and callus non-responsive lines. From the present set, no marker could clearly differentiate its association with calli and callus responding lines. RM228 and RM23662 markers had heterozygous alleles in the callus indicating their origin from the callus wall. Studies on wide crosses of rice x maize and rice x pearl millet indicated strong pre-fertilization barrier. Pollen tube of maize failed to penetrate the stigma of rice even up to 48 hours of observations. The pollen tube of pearl millet penetrated the stigma in some samples of rice but only one pollen tube of pearl millet out of 400 microscopic fields was found to reach near the micropylar end at 24 hours of cross-pollination. Hence, pearl millet could be a better candidate for further study of wide crosses of rice for induction of haploids. Pseudo seed formation was observed in the wide crosses of rice due to application of 2, 4-D in low frequencies. Further, studies on media manipulation, identification of genes/QTLs for anther culturability, overcoming barrier of wide crosses in rice x pearl millet and exploration of new alternate techniques like use of CENH3, OSMATL and BBM1 are suggested. | en_US |
| dc.identifier.uri | http://krishikosh.egranth.ac.in/handle/1/5810134995 | |
| dc.keywords | Doubled haploids, Anther culture, Anther culturability, Wide crosses | en_US |
| dc.language.iso | en | en_US |
| dc.pages | 100 | en_US |
| dc.publisher | Punjab Agricultural University, Ludhiana | en_US |
| dc.research.problem | Production of doubled haploids in rice (Oryza sativa L.) through anther culture and wide crosses and their molecular characterization | en_US |
| dc.sub | Genetics and Plant Breeding | en_US |
| dc.subject | null | en_US |
| dc.theme | Production of doubled haploids in rice (Oryza sativa L.) through anther culture and wide crosses and their molecular characterization | en_US |
| dc.these.type | Ph.D | en_US |
| dc.title | Production of doubled haploids in rice (Oryza sativa L.) through anther culture and wide crosses and their molecular characterization | en_US |
| dc.type | Thesis | en_US |