Biochemical and molecular characterization of aerobic and lowland indica rice (Oryza sativa L.) varieties
| dc.contributor.advisor | Jain, Sunita | |
| dc.contributor.author | Dahiya, Anjali | |
| dc.date.accessioned | 2017-09-29T05:01:46Z | |
| dc.date.available | 2017-09-29T05:01:46Z | |
| dc.date.issued | 2017 | |
| dc.description.abstract | In the present investigation, biochemical and molecular characterization of aerobic (MAS25 and MAS26) and high yielding lowland (HBC19, HKR47, PUSA1121 and PAU201) indica rice varieties were carried out under aerobic and well watered conditions in the greenhouse to understand the mechanism(s) of water efficiency in rice. Data was recorded on various physio-morphological parameters and activities of key enzymes and metabolites of glycolytic, HMP, fermentative and proline metabolizing pathways in root and shoot tissues at early vegetative, late vegetative and reproductive stages. Relative expression of DRO1 and genes of proline metabolism using real time PCR were also observed. Aerobic compared to low-land rice varieties, invariably had higher root length, and root biomass under under aerobic conditions. Activities of the enzymes of glycolytic (hexokinase, phoshofructo kinase, fructose-1,6-bisphosphate aldolase, pyruvate kinase), HMP (glucose -6- phosphate dehydrogenase, 6-phospho gluconate dehydrogenase) and fermentative (alcohol dehydrogenase, lactate dehydrogenase and alanine aminotransferase) pathways in both the tissues declined under aerobic conditions but reduction was significantly lower in aerobic (MAS25 and MAS26) varieties. Rice cultivation under aerobic conditions also affected the levels of various metabolites. While ethanol, lactate and alanine contents decreased, levels of reducing sugar and total sugars increased in both the tissues of all the six rice varieties under aerobic conditions. Significant positive correlation was observed between per cent change in PFK1 activity and other glycolytic (HXK, FBP aldolase and PK) enzymes’ activities, between enzymes and metabolites of fermentative pathway in roots and shoots at all the stages. High basal levels of proline content and proline synthesizing enzymes, pyrroline-5-carboxylate synthetase (P5CS) and pyrroline-5-carboxylate reductase (P5CR) were observed in root as well as shoot tissues of aerobic rice genotypes in comparison to lowland rice varieties, however, per cent enhancement was more pronounced in lowland varieties under aerobic conditions. Contrarily, proline oxidase (ProDH), the proline degrading enzyme had lower activity in aerobically grown plants of all the six varieties. Relative expression of P5CS and P5CR genes increased while that of ProDH declined more in MAS26 under aerobic conditions as compared to HBC19 in both the tissues. A positive correlation was observed between proline content and both the enzymes involved in its biosynthesis while there was a negative correlation between proline content and proline oxidase activity. In roots, expression of DRO1 declined in HBC19 (57%) but increased by 41% in MAS26 under aerobic conditions. Higher expression of DRO1, P5CS and P5CR genes and levels of proline in aerobic compared to lowland indica rice varieties may be the potential reasons for the better growth and productivity in aerobic rice under less water conditions. | en_US |
| dc.identifier.uri | http://krishikosh.egranth.ac.in/handle/1/5810031944 | |
| dc.keywords | Aerobic rice, Water stress, Glycolytic, HMP, Fermentative, Proline, DRO1 | en_US |
| dc.language.iso | en | en_US |
| dc.publisher | CCSHAU | en_US |
| dc.sub | Biochemistry | en_US |
| dc.subject | null | en_US |
| dc.theme | Biochemical and molecular characterization of aerobic and lowland indica rice (Oryza sativa L.) varieties | en_US |
| dc.these.type | Ph.D | en_US |
| dc.title | Biochemical and molecular characterization of aerobic and lowland indica rice (Oryza sativa L.) varieties | en_US |
| dc.type | Thesis | en_US |