Effect of tuber planting depth on yield, quality and profitability of potato (Solanum tuberosum) processing varieties

A field experiment was conducted during 200910 and 201011 at Central Potato Research Institute, Regional Station, Modipuram, Uttar Pradesh, to evaluate the effect of 3 planting depths (10, 15 and 20 cm) on 2 potato (Solanum tuberosum L.) processing varieties, Kufri Frysona and Kufri Chipsona 1. In both the processing vari- eties, final plant emergence and growth traits (plant height, stem and leaf number/plant) decreased significantly at 20 cm depth of planting. Increase in tuber planting depth increased the depth of tuber setting. Kufri Frysona tu- bers were found little deeper (by 1 cm) than Kufri Chipsona 1. Maximum processing grade (French fry and chip grade) and total tuber number were realized at 10 cm planting depth. The lowest number and yield of green tuber recorded at 20 cm depth of planting. The maximum french fry-grade tuber yield was recorded at 10 cm depth of planting in cv. Kufri Frysona, whereas it was the highest at 15 cm planting depth in Kufri Chipsona 1; however, total tuber yield was the maximum at 10 cm depth of planting in both the varieties. Total tuber yield was signifi- cantly higher in Kufri Frysona than Kufri Chipsona 1 at 10 cm planting depth only. Highest net returns and ben- efit: cost ratio were recorded at 10 cm planting depth and decreased with the increase in planting depth. Similarly, Kufri Frysona recorded higher net returns and benefit: cost ratio than Kufri Chipsona 1, under shallower depths of planting (10 cm and 15 cm). French fry colour was observed best at 10 cm seed tuber depth of planting. Me- dium size (5060 g) seed tuber of processing varieties, Kufri Chipsona 1 and Kufri Frysona may be planted at 10 cm depth of planting for realizing higher processing grade (French fry + chip grade) and total tuber yields, maxi- mum net returns and benefit: cost ratio along with best fry quality.