Effect of CO۲ Enrichment on Gas Exchanges, Biochemical Traits, and Minituber Yield in Potato (Solanum tuberosum L.) Cultivars

Micro-propagated potato plantlets (cvs. Agria and Fontane) were grown in growth chambers under controlled conditions to determine the effect of different levels of CO۲ concentrations (۴۰۰ vs. ۸۰۰ µmol mol−۱) on physiological and biochemical traits and yield of minitubers, at the Ferdowsi University of Mashhad, in ۲۰۱۵. Irrespective of the cultivar, the elevated CO۲ significantly increased Net photosynthesis (Np) and leaf Dark Respiration (RD) compared to the control at ۳۴ and ۵۷ days after transplanting. Higher Np under the elevated CO۲ resulted in a higher accumulation of leaflet starch and soluble sugar content. The elevated CO۲, compared to the ambient, induced allocation of more dry matter to the underground parts, especially tubers. CO۲ Enrichment did not significantly affect the number of tubers and mean tuber weight, however, the elevated CO۲ increased yield of Agria and Fontane by ۱۷ and ۳۹%, respectively. The yield of Fontane was increased more than Agria when exposed to elevated CO۲, mainly due to greater mean tuber weight than tuber number. The number of large size tubers increased under elevated CO۲. The results showed that the greater mean tuber weight might affect tuber yield more than the number of tubers. Our findings suggest that rising levels of CO۲ in minituber production systems could be beneficial to improve productivity and tuber yield.

Keywords:

Carbohydrate , Dark respiration , Dry matter partitioning , Photosynthetic rate , Starch. , تنفس تاریکی , تسهیم ماده خشک , فتوسنتز خالص , محتوای کربوهیدات محلول برگ , محتوای نشاسته برگ