A study on newly developed wheat-Aegilops kotschyi derivative lines, putative genes for iron homeostasis and EMS mutants for biofortification of hexaploid wheat with iron and zinc
| dc.contributor.advisor | Sundip Kumar | |
| dc.contributor.author | Naveen Kumar | |
| dc.date.accessioned | 2019-01-31T10:32:06Z | |
| dc.date.available | 2019-01-31T10:32:06Z | |
| dc.date.issued | 2018-06 | |
| dc.description.abstract | Micronutrients (Fe and Zn) malnutrition affects more than 2 billion people worldwide. Wheat is one of the most important staple crops, which provides more than 40% calories at different parts of the globe. Modern cultivars of wheat have lower concentration and limited variability of grain micronutrients in comparison to its wild relatives. The biofortified line of wheat (3P-3-2) developed through wide hybridization among hexaploid wheat and Aegilops kotschyi 396 followed by pollen irradiation was observed to have at par yield with three of the wheat checks namely PBW343(Lr24+GPCB1), PBW703/698 and HD2967(Yr40+Lr57). This line has shown more than 35% (39.7 mg/Kg) increase in Fe over PBW343(Lr24+GPCB1) (29.33 mg/Kg) and more than 23% (34.41 mg/Kg) increase in Zn over PBW343(Lr24+GPCB1) (27.76 mg/Kg). The overall impact of this high concentration of micronutrients is directly based on their bioavailability which is influenced by antinutritional (tannins and phytic acid) and nutritional (beta-carotene and ascorbic acid) factors. Hence, hexaploid wheat, its wild relatives, wheat-Ae kotschyi derivative lines and advanced biofortified lines were studied to analyze the bioavailability of Fe and Zn. The higher contents of ascorbic acid was estimated in Aegilops longissima (1.29 ppm) (Acc. 3507) and biofortified line S-944-2 (1.112 ppm) and the higher contents of beta-carotene was estimated in Triticum monococcum 473 (6.89 ppm), Aegilops kotschyi-393 (6.86), S-934-2 (5.28 ppm) and S-934-3 (5.29 ppm). The lower contents of phytic acid was observed in Aegilops longissima (Acc. 3507) (10.86 mg/g), Aegilops kotschyi (Acc. 3502) (12.52 mg/g) and biofortified line (R-10) (11.96 mg/g) and the lowest contents of tannic acid were observed in Ae. dicoccoides (Acc. W-744) (9.27 ppm) and the biofortified line S-933-3 (11.19 ppm). To explore the iron homeostasis genes diversity in hexaploid wheat and its progenitors, the insilico characterization of iron homeostasis gene was done. In-silico characterization results indicates the presence of five NAS genes each from the Triticum urartu, Aegilops speltoides and Aegilops tauschii and the presence of 20 NAS genes in hexaploid wheat Chinese spring on group 2, 3, 4, 5 and 6 of chromosomes. Three of the six NAAT genes were characterized as NAAT1 and other three were as NAAT2 on long arm of chromosomes of group 1 while 2 genes (TuNAAT1 and TuNAAT2) from Triticum urartu and one gene each from Aegilops speltoides (AespelNAAT2) and Aegilops tauschii (AeTauNAAT1). Three DMAS genes were identified in wheat cultivar Chinese spring which were present on the group 4 chromosome, while single gene was identified each from Triticum urartu, Aegilops speltoides and Aegilops tauschii. The in-silico characterization of NAAT and DMAS genes indicated variation in length of these genes. The variation in homologous genes are more likely due variation in the length of intron sequences. Further gene expression studies of three of these genes in hexaploid wheat (Chinese spring) indicates that the iron deficiency and age of the plant directly regulates the expression of these three (TaNAAT, TaDMAS and TaNAS9A) genes in wheat roots while TaIDEF2 was found to be post transcriptionally regulated. From the newly developed mutant population in wheat cultivar DPW 621-50, we have identified a the putative glyphosate tolerant plant, a putative lodging tolerant plant (Lt-1) and other mutants for various traits which may further be helpful in mapping genes for these traits. In addition to the above mentioned traits the mutant’s population was also used to isolate the mutants containing higher contents of minerals (Ca, Cu, Fe and Zn) in grains. The mutant line M-152-P-1 has 131.17% (60.77 ppm) Zn, 112% (89.09 ppm) Fe over the parent cultivar (DPW 621-50). The mutant line DWF-21 and Bus-2-P-2 has 86.76% (206.36 ppm) and 85.20 % (204.63 ppm) increase in their Ca contents in comparison to DPW 621-50 while lines M-9-P-4 and DWF- 47 has 110.5 % and 104.80 % in Cu in comparison to the control. | en_US |
| dc.identifier.uri | http://krishikosh.egranth.ac.in/handle/1/5810093162 | |
| dc.keywords | Aegilops kotschyi, genes, homeostasis, mutants, fortification, wheat, iron, zinc | en_US |
| dc.language.iso | en | en_US |
| dc.pages | 307 | en_US |
| dc.publisher | G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand) | en_US |
| dc.research.problem | Wheat | en_US |
| dc.sub | Agricultural Biotechnology | en_US |
| dc.subject | null | en_US |
| dc.theme | Molecular Biology and Biotechnology | en_US |
| dc.these.type | Ph.D | en_US |
| dc.title | A study on newly developed wheat-Aegilops kotschyi derivative lines, putative genes for iron homeostasis and EMS mutants for biofortification of hexaploid wheat with iron and zinc | en_US |
| dc.type | Thesis | en_US |