The eastern sub-Himalayan plain of India is a popular potato growing belt in which vast scope exists to introduce processing grade cultivars. The selection and introduction of a better quality processing grade cultivar in this region may pave the way for the processing industries. Keeping these in the backdrop, this study was conducted at Instructional Farm of Uttar Banga Krishi Viswavidyalaya (UBKV), Pundibari, Cooch Behar, West Bengal, India under eastern sub-Himalayan plains during winter seasons of 2016–17 and 2017–18 in which seven processing type potato cultivars (Kufri Chipsona-1, Kufri Chipsona-3, Kufri Chipsona-4, Kufri Frysona, Kufri Himsona, Kufri Surya and Kufri Chandramukhi) were evaluated in terms of different quality parameters pre-requisite for chips processing viz., dry matter content, specific gravity, starch content, chips colour score, crispiness and hardness of chips through randomised complete block design (RCBD). The study revealed wide variation in all quality parameters amongst the cultivars. Cultivar ‘Kufri Frysona’ showed the highest specific gravity (1.121) as well as dry matter content (23.35%) followed by ‘Kufri Chipsona-3’. The cultivar ‘Kufri Frysona’ showed the highest starch content (28.52%) too. Chips prepared from ‘Kufri Chipsona-1’ were recorded to be crispier with a relatively lower value of deformation before the first break and less hardness value. All processing type potato cultivar reflected the chips colour score <3 (evaluated, based on 1–10 scale, 10 being the darkest and least desirable) though ‘Kufri Frysona’ had the lowest chips colour score (1.50) signifying its superiority for the region. ‘Kufri Frysona’ cultivation could be recommended in this agro-climatic region particularly for chips manufacturing potato industries.

The present study was conducted in the eastern sub-Himalayan plains of West Bengal, India, to evaluate 21 potato cultivars (including table- and processing-type) and assess their suitability in terms of improved physiological responses, yield performances, stability and profitability. A significant difference in various growth attributes, i.e., plant height, number of stems per plant, leaf area index (LAI), dry matter (DM) accumulation, and crop growth rate (CGR), was noted amongst different cultivars. Significant variation was also observed in net photosynthesis rate (NPR), transpiration rate (TR), and stomatal conductance rate (SCR) recorded at various stages of growth. Amongst all the cultivars, ‘Kufri Chipsona-4’ showed the highest SCR at both 60 and 80 days after planting (DAP), while ‘Kufri Pokhraj’ had the highest NPR at both 60 and 80 DAP. However, the highest TR was achieved with ‘Kufri Chipsona-3’and ‘Kufri Surya’ at 60 and 80 DAP, respectively. ‘Kufri Pukhraj’ and ‘Kufri Himsona’ achieved the maximum and minimum tuber bulking rate (TBR) values at initial growth stages (upto 60 days), respectively; however, ‘Kufri Arun’ and ‘Kufri Surya’ had significantly higher TBRs during the later part of growth (after 60 days to maturity), leading to higher tuber yields amongst the medium maturing cultivars. Among the 21 cultivars, ‘Kufri Arun’ showed the maximum total tuber yield (35.52 t/ha), followed by ‘Kufri Pukhraj’ (33.54 t/ha) with higher marketable grade tubers. In terms of production economics, ‘Kufri Arun’ achieved the maximum net return (USD 2137.4) and B:C (benefit:cost) ratio (2.17), suggesting the suitability of this cultivar in the eastern sub-Himalayan plains of West Bengal. The early maturing ‘Kufri Pukhraj’ and processing variety ‘Kufri Chipsona-3’ also showed their suitability in terms of net returns and B:C ratio. The heat-tolerant variety ‘Kufri Surya’ also achieved a tuber yield of 31 tha⁻¹ with satisfying net return (USD 1596.9) and B:C ratio (1.88), suggesting the suitability of this cultivar in this region under terminal heat stress. However, the stability analysis showed that the cultivars ‘Kufri Khyati’ and ‘HPS II/67’ were the most stable in terms of additive main effect and multiplicative interaction (AMMI) stability value (ASV) and yield stability index (YSI), respectively.