Book of Extended summaries ISDA

International Conference on Reimagining Rainfed Agro-ecosystems: Challenges &
Opportunities during 22-24, December 2022 at ICAR-CRIDA, Hyderabad
Prajapat, K., Vyas, A.K. and Dhar, S. 2015. Effect of cropping systems and nutrient
management practices on growth, productivity, economics and nutrient uptake of
soybean (Glycine max). Indian J. Agric. Sci., 85(9): 1138-1143.
Managing genetic resources for enhanced stress tolerance
T3-04O-1123
Samrat Bt – A New, Early Maturing Bt Cotton Variety for Stress Resilience
and Multiple Cropping in Rainfed Agro-Ecologies of South India
H. B. Santosh *1,4 , S. Manickam 1 , S. B. Singh 1 , V. N. Waghmare 1 , K. P. Raghavendra 1 ,
Vivek Shah 1 , K. R. Kranthi 2 , Kunal Gaikwad 1 , S. S. Patil 3 , G. Ravindra Chary 4 and
V.K. Singh 4
1 ICAR – Central Institute for Cotton Research, Nagpur 440010, Maharashtra
2 International Cotton Advisory Committee, Washington DC 20006-1635, USA
3 University of Agricultural Sciences, Dharwad 580005, Karnataka
4 ICAR-Central Research Institute on Dryland Agriculture, Hyderabad 500059
* hb.santosh@icar.gov.in
Bt cotton was developed as an alternate strategy to the previously used hazardous insecticides
to circumvent bollworm problem. Though majority of cotton production in India comes from
Bt cotton, the cotton productivity in India is low compared to world average (>750 kg/hectare)
and is found stagnated at around 500 kg lint per hectare for past many years (Kranthi and Stone,
2020). One of the reasons attributed to this productivity stagnation is deployment of Bt
technology in the form of Bt hybrids in rainfed conditions which accounts to more than 60%
of cotton area in India. Majority of the popular Bt hybrids are long duration that suffer moisture
stress at boll formation stage due to poor water retention of shallow soils in rainfed regions.
Productivity enhancement in India can come from yield improvement in rainfed ecosystems
through development and deployment of Bt cotton varieties (Singh et al., 2021). Additionally,
to address the menace of Pink bollworm and also to enable farmers taking multiple crops, we
embarked upon development of early maturing Bt cotton varieties for rainfed agro-ecologies
of India.
Methodology
An F 2 population of the 4 parental cross [(Bikaneri Narma Bt × RCRSC7) × (RCRSC2 ×
RCRSC12)] was phenotyped for traits of interest like crop maturity, plant architecture, jassid
tolerance, yield and fibre quality attributes at ICAR-CICR, Nagpur during Kharif, 2013-14.
The promising plants were selected, advanced and stabilized through pedigree breeding during
2014-15 to 2017-18. The presence of Bt gene (cry1Ac) and transgenic event (Mon531) was
confirmed through ELISA and event specific PCR. The homozygosity of the transgene was
confirmed through zygosity PCR. The rapid generation advancement was achieved by taking
off-season crop at CICR Regional Station, Coimbatore, Tamil Nadu. The most promising
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