IMPACT OF CONCURRENT ELEVATION IN CO2 AND TEMPERATURE ON TUBER YIELD AND ASSOCIATED TRAITS OF POTATO GENOTYPES

Abstract

Carbon dioxide (CO2) concentration in the atmosphere is rising continuously and consequently global average
surface temperature is anticipated to rise in near future which tends to affect tuber yield, associated physiological traits of
potato. This necessitate to explore some resilient cultivars to counter the adverse impact of anticipated changing climate
scenario. So, in order to explore such cultivars, an investigation was carried out in open top chambers having controlled
facility (CO2 and Temperature) at ICAR-CPRS, Jalandhar, Punjab. Two advance stage heat tolerant potato genotypes viz.,
HT/7-1105 and HT/7-1329 and two commercial varieties, viz., Kufri Surya (heat tolerant) and Kufri Badshah were evaluated
under three treatments, viz., (i) elevated CO2 (600 ppm) along with elevated temperature (30C rise over ambient); (ii)
elevated CO2 (600 ppm) and (iii) ambient. Impact of higher temperature with elevated CO2 on tuber yield was negative
only in Kufri Badshah (-10.17 t/ha). Response to CO2 enrichment, in terms of tuber yield, was positive in case of all the
genotypes i.e. Kufri Badshah, Kufri Surya, HT/7-1105 and HT/7-1329. These results suggest the overall superiority of Kufri
Surya and heat tolerant cultivars in terms of productivity under high CO2 and high temperature. Net photosynthesis (PS)
rate was 34.4 μmol CO2 m-2s-1 under elevated CO2 in Kufri Badshah that reduced to 27.10 μmol CO2 m-2s-1 on exposure to
high temperature (around 3oC) and CO2. These values were statistically significant over PS rate under ambient conditions.