Mohanpuria, PrashantRavinder Kaur2022-12-032022-12-032022Ravinder Kaur (2022) Cloning of vitellogenin gene of whitefly, Bemisia tabaci (Gennadius) into RNAi vector for genetic transformation of upland cotton (Unpublished M.Sc. thesis). Punjab Agricultural University, Ludhiana, Punjab, India.https://krishikosh.egranth.ac.in/handle/1/5810190294Cotton is India's important cash crop, and it plays a significant part in the country's industrial and agricultural economy. Whitefly (Bemisia tabaci) has been one of the most threatening polyphagous pests of cotton and no whitefly resistance germplasm is reported in India. Also, there are no Bacillus thuringiensis (Bt) toxins known to be effective against whitefly. Generating RNAi cotton plants expressing dsRNA of vital gene of whitefly can be a novel approach to produce whitefly resistance in available Bt cotton variety. In present work, 208bp cDNA fragment of vitellogenin gene (VG) gene of whitefly was used to prepare an RNAi construct. The cloning of RNAi cassette was confirmed through PCR with vector specific primer sets. Agrobacterium harboring prepared RNAi construct was used to transform cotton variety, PAU Bt3. The germinated cotton seeds containing hypocotyledonary region of mature embryo was used as an explant (pricking and without pricking) for Agro-inoculation for different incubation periods (90 and 120 minutes) and thus, a cultivar-independent, in planta genetic transformation protocol has been standardized. In transformation one cotyledon was removed followed by pricking with needle on hypocotyledonary region resulted in 29 PCR (with RNAi cassette specific primers in isolated DNA) positive RNAi cotton plants with overall cotton transformation efficiency was 3.29%. PCR was also attempted in DNA isolated from all confirmed RNAi cotton plants with Vir C gene specific primers which showed absence of Agro contamination in these plants even after 5-6 months of transformation. These RNAi cotton plants will be further characterized in future.EnglishThesis