Potato Cultivars In Potato

EFFECTS OF TEMPERATURE ON POTATO YIELD

Potato (Solanum tuberosum) is a cool season crop with its vegetative parts and the underground parts requiring different temperatures, but it performs best at temperatures around 20 0C. High temperatures during the growing season induce numerous changes in the potato plants, which affect its growth and development and ultimately leading to reduction in its yield, (Wahid et al. 2007).

However, potato cultivars that are heat tolerant show comparatively little decrease in yield as a result of the effects of high temperature, they do not also form secondary tubers and they have less number of tubers with physiological defects, Rykaczewska, (2015).

High temperatures can have adverse effects on potato yields

The earlier high temperature occurs during the growth stage, the more negative its impact on the growth and yield of potatoes, Rykaczewska, (2013). In an assessment of the response of six (6) potato cultivars to high temperature 320C/250C, day/night during different stages of plant growth, Rykaczewska, (2013), showed that the effects of high temperature during flowering period may reduce the yield of susceptible cultivars by over 50% and more tolerant cultivars by about 25%. However, Wivutvongvana, (1979) observed that the varietal differences in sensitivity to high temperatures may be associated more with differences in their respiration rate than in photosynthetic rate. He compared heat-tolerant and susceptible clones of Solanum chacoense and Solanum acaule and found that the susceptible clones have higher rates of dark respiration than the heat-tolerant clones but they did not differ in the rate of CO2 uptake during photosynthesis, suggesting that tolerance to high temperatures may be associated more with differences in respiration than in

The growth stages which can be divided in to, the period of initial emergence and beginning of development of the plant to the early period of tuber initiation, the period of tuber initiation and start of tuber development and lastly, the period of increased tuber bulking and the start of maturation, all have different temperature requirements. The effects of temperature on potato is further complicated by the time and place of taking the temperature and the plant parts being measured. Furthermore, day and night optimum temperatures, soil and air optimum temperatures, may all differ. In addition, there is the environmental as well as the genetic differences and their interaction with one another, which will all surely play important roles in making the effects of temperature on potato growth and yield more