Potato

• Potato is both thermo & photosensitive crop. It is a cool season crop. Potato is planted within temperature range is 18-320C and tuber development most rapidly occur when day temperature is 20-210C and night temperature is below 140C.
• Most of the potato genotype do not tuberize when night temperature is more than 230C. From emergence to tuber initiation stage, optimum temperature is 250C. For the period of tuber initiation to early stage of tuber development, potato requires low temperature i.e. 15-180C and for tuber enlargement to maturation period high temperature is required i.e. 290C.
• Tuber yield decreases in higher temperature due to reduction of synthesis of carbohydrates over that consumed in respiration. So, temperature above 250C decreases tuber formation.
• Optimum soil temperature for potato crop varies with different stages of the plant. Similarly, mild frost to the extent of -10C partially damages the potato leaves but when temperature falls below -20C, the exposed part of the most of the varieties are damaged.
• Sprout development in soil is rapid at a constant temperature of about 240C. However, the later growth will be better at approximately 180C.
• Soil temperature above 240C causes excessive branching of young sprouts, shortening of internodes & decrease in fragmentation of leaves.
• Water requirement for potato crop during its vegetative period are not very high. Fifteen to twenty cm of rainfall or irrigation is sufficient.