MORPHO-PHYSIOLOGICAL EVALUATION AND DNA FINGERPRINTING OF DROUGHT QTL INTROGRESSED RICE GENOTYPES

Simple item page
dc.contributor.advisorChetia, Sanjay Kumar
dc.contributor.authorAdhikari, Pragyan
dc.date.accessioned2024-07-18T06:22:29Z
dc.date.available2024-07-18T06:22:29Z
dc.date.issued2023
dc.description.abstractRice (Oryza sativa L.) holds a significant position as one of the world's most crucial cereal crops, serving as a staple food for a vast majority of the global population. In India, it plays a vital role, contributing around 45 percent to the total cereal production and serving as the primary food source for over 60 percent of the population. Developing countries, particularly in Asia, Africa, and Latin America, contribute more than 90% to the world's total rice production. However, around 40% of the world’s rice is produced under rainfed environment, making it vulnerable to the adverse effects of low rainfall. Drought stands out as a major abiotic stress factor that leads to reduced yields. Rice faces even greater challenges due to its semi-aquatic nature and high-water requirement. Keeping the significance of drought stress in mind, an effort to introgress drought QTLs into some of the popular rice varieties of Assam was made at AAU – Assam Rice Research Institute, Titabar. In the present study, morpho-physiological evaluation of 17 drought QTL introgressed lines along with 4 checks (IR64 drought, Sahbhagi Dhan, Luit and Lachit) was carried out in a field experiment laid out in Randomised Block Design with three replications under irrigated and drought stress conditions. 10 traits; 7 morphological viz., leaf rolling, days to 50% flowering, ear bearing tillers, panicle length, spikelets per panicle, spikelet fertility and grain yield per plant and 3 physiological traits viz., chlorophyll content, relative leaf water content, excised leaf water loss were studied. Significant variation was observed among the genotypes for all the 10 traits evaluated under drought stress conditions, while under irrigated conditions, significant variation was observed for all traits except relative leaf water content and spikelet fertility. Highest GCV and PCV values were observed for spikelets per panicle (19.46 and 20.12 respectively) under irrigated conditions and leaf rolling (70.30 and 74.17 respectively) under drought stress conditions. High heritability coupled with high genetic advance as percentage of mean were exhibited by 3 traits, viz., chlorophyll content, ear bearing tillers and spikelets per panicle under both irrigated and drought stress conditions, while leaf rolling and grain yield per plant displayed high heritability coupled with high genetic advance as percentage of mean under drought stress conditions. Genotyping was done using the linked SSR markers to confirm the presence of the QTLs and the study revealed that 4 lines out of the 17 lines evaluated contained all three introgressed QTLs (qDTY 1.1, qDTY 2.2 and qDTY 4.1). DNA fingerprinting was also carried out for the lines under study using 50 SSR panel markers selected from Gramene, out of which 11 were found to be polymorphic. The PIC content of the markers varied from 0.0023 (RM152) to 0.7460 (RM154). A dendrogram constructed from the dissimilarity index grouped the population into 3 clusters. Based on the evaluation, the four best-performing lines Luit x IR64 Drought (4.13-1), Kolong x IR64 Drought (4.4-2), Kolong x IR64 Drought (12.1-4) and Kopilee x IR64 Drought (2.1-2) were identified which may be sent for multilocation trials and subsequently be released and notified. These lines hold promise in assisting farmers to better manage and mitigate the impact of drought stress.
dc.identifier.urihttps://krishikosh.egranth.ac.in/handle/1/5810212173
dc.language.isoEnglish
dc.subGenetics and Plant Breeding
dc.themeMORPHO-PHYSIOLOGICAL EVALUATION AND DNA FINGERPRINTING OF DROUGHT QTL INTROGRESSED RICE GENOTYPES
dc.these.typeM.Sc
dc.titleMORPHO-PHYSIOLOGICAL EVALUATION AND DNA FINGERPRINTING OF DROUGHT QTL INTROGRESSED RICE GENOTYPES
dc.typeThesis
Files
Original bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
MORPHO-PHYSIOLOGICAL EVALUATION AND DNA FINGERPRINTING OF DROUGHT QTL INTROGRESSED RICE GENOTYPES.pdf
Size:
2.27 MB
Format:
Adobe Portable Document Format
Download
License bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
license.txt
Size:
1.71 KB
Format:
Item-specific license agreed upon to submission
Description:
Download
Collections
Theses