Indian potato (Solanum tuberosum L.) processing industry has emerged fast due to economic liberalization coupled with growing urbanization, expanding market options and development of indegenous processing varieties. India's first potato processing varieties 'Kufri Chipsona-1' and 'Kufri Chipsona-2' were developed in 1998, followed by an improved processing variety 'Kufri Chipsona-3' in 2005 for the Indian plains and first chipping variety 'Kufri Himsona' for the hills. These varieties have >21% tuber dry matter content, contain low reducing sugars (<0.1% on fresh wt) and are most suitable for producing chips, French fries and dehydrated products. The availability of these varieties and standardization of storage techniques for processing potatoes at 10-12°C with sprout suppressant isopropyl N-(3-chlorophenyl) carbamate have revolutionized the processing scenario within a short span of 10 years. Currently about 4% of total potato produce is being processed in organized and unorganized sector. Potato processing industry mainly comprises 4 segments: potato chips, French fries, potato flakes/powder and other processed products. However, potato chips still continue to be the most popular processed product. The major challenge facing the industries lies in arranging round the year supply of processing varieties at reasonable price for their uninterrupted operation, besides several others which have been discussed at length and addressed with concrete solutions.

Peroxidase activity was determined in the leaves of early (70-80 days maturity), medium (90-100 days), and late maturing (100-120 days) potato (Solanum tuberosum) germplasm accessions at 30, 50, and 70 days after planting. Enzyme activity was lowest in early maturing cultures, whereas late maturing cultures exhibited the maximum activities with medium maturing ones showing intermediate values at all three stages of crop growth. Peak enzyme activity was observed at the 30-day stage, irrespective of the maturity group, and declined thereafter. Mean peroxidase activity in the leaves at the pre-tuber initiation stage (30 days) was 25.3, 40.3, and 74.0 ΔA min -1 g -1 fresh weight, in early, medium, and late maturing cultures, respectively. The large differences in the enzyme activities of (at the 30-day stage) can be used as a biochemical marker for identifying cultivars belonging to different maturity groups.

Changes in the chemical constitutents of potato tubers grown under different concentrations of 3 synthetic organic nematicides (carbofuran, aldicarb and phorate) and a natural plant product (sawdust) were investigated. There were no significant differences in the specific gravity, dry matter and starch content of tubers from different treatments. A significant increase in the content of non-reducing and total sugars was observed in all the treatments. Nematicidal treatments had significant effects on reducing sugars, true protein, free amino acids, orthodihydroxy phenols, beta-carotene and ascorbic acid. Application of nematicides reduced the content of total phenolic compounds which is a desirable change from a processing viewpoint. Potatoes grown under different nematicidal treatments can be processed into chips and French fries as they contain permissible levels of reducing sugars required for these forms of processing.