Development of transgenic cotton (Narasimha) using triple gene Cry2Ab-Cry1F-Cry1Ac construct conferring resistance to le
- PDF / 4,126,128 Bytes
- 11 Pages / 595.276 x 790.866 pts Page_size
- 47 Downloads / 163 Views
Ó Indian Academy of Sciences (0123456789().,-volV) (0123456789().,-volV)
Development of transgenic cotton (Narasimha) using triple gene Cry2Ab-Cry1F-Cry1Ac construct conferring resistance to lepidopteran pest SUMALATHA KATTA1,3, ASHWINI TALAKAYALA1, MALIREDDY K REDDY2, UMA ADDEPALLY3 and MALLIKARJUNA GARLADINNE1* 1
Plant Molecular Biology Laboratory, Agri Biotech Foundation, Rajendranagar, Hyderabad 500 030, India
2
Crop Improvement Group, International Center for Genetic Engineering and Biotechnology, New Delhi 110 046, India 3
Center for Biotechnology, Jawaharlal Nehru Technological University, Hyderabad 500 085, India *Corresponding author (Email, [email protected]) MS received 12 February 2019; accepted 31 October 2019
High-yielding Indian cotton varieties are not amenable for regeneration and transformation because they are recalcitrant in nature. In this work, we have developed Narasimha (NA1325) cotton variety by introducing three Cry genes driven by three different promoters conferring insect resistance. The meristematic region of embryo axis explants were infected and co-cultivated with Agrobacterium tumefacience (LBA4404) harbouring pMDC100 vector with three Cry gene cassettes (a-globulin : Cry2Ab, DECaMV35s : Cry1F and nodulin : Cry1Ac) with Npt II as a selectable marker gene. Out of 1010 embryo axes explants infected, 121 (T0) regenerated under two rounds of kanamycin selection medium. About 2551 T1 seeds were collected from 111 T0 plants and these seeds screened again with kanamycin at seedling stage. The transgenic plants were characterized by PCR, real time quantitative PCR, lateral flow strip protein assay and insect bioassay. Out of 145 kanamycin resistant plants (T1), twelve showed amplification of all four transgenes: Npt II, Cry2Ab, Cry1F and Cry1Ac through PCR with expected amplicons as 395, 870, 840 and 618 bp, respectively. Further, lateral flow strip test revealed Cry1F and Cry1Ac proteins accumulated in 12 plants, whereas Cry2Ab protein was detected in eight only. The transcripts of all three Cry genes were accumulated significantly higher in transgenic plants at T2 generation. The transgenic lines showed effective resistance against Helicoverpa armigera and Spodoptera litura larvae. The T2 line L-3 exhibited highest percentage of insect mortality, in which transcripts of all cry genes were accumulated higher than other plants. The transgenic cotton plants carrying triple Cry genes could be an excellent germplasm resource for the breeders for introgressions. Keywords. Agrobacterium; acetosyringone; embryo axes; Helicoverpa armigera; Spodoptera litura; Cry2Ab; Cry1F; Cry1Ac transcripts
1. Introduction Cotton (Gossypium hirsuturm L) is an important commercial crop, being cultivated in several countries and serving the purpose of textile industry, animal feed, seed oil, etc. The annual cotton production was 23 million metric tons globally (www.cottoninc.com), with
India being the largest producer (6.2 mt), during 2017–2018 (FAOSTATS, 2017-18). But, evolution of resistant bollworms
Data Loading...
