Physiological age of potato seed tubers and its role in plant growth, yield, and quality response to irrigation regime.

摘要

The physiological age of seed tubers can be an important factor in potato crop performance. It is known to affect sprouting capacity and initial plant vigor as well as subsequent plant growth and development.; Several storage experiments addressed the relation between electrolyte leakage from potato tuber tissue and sprouting capacity. An increase in electrolyte leakage was observed after tubers started to sprout. Sprouting capacity of tubers was affected by physiological age in that it increased to a maximum and then declined over time in storage. The decline in sprouting capacity coincided with the increase in electrolyte leakage, suggesting membrane integrity as a possible factor in vigor of seed tubers.; In a three year field study, the effect of physiological age of seed tubers on growth, development and tuber quality of potatoes grown under different irrigation regimes was investigated as well as the interaction between seed tuber age and irrigation regime. The effect of seed tuber age was most apparent by its increase in stem number. The higher number of stems resulted in more and smaller tubers, higher early season tuber yields, and a tendency for improved specific gravity. A lower susceptibility to second growth was observed in one year for tubers from aged seed. The effect of seed age was independent of irrigation regime as the interaction was not significant for two contrasting cultivars. The same conclusion was reached in a greenhouse study where plants from physiologically young and pre-sprouted, old seed tubers were subjected to temporary drought after tuber formation. Although plant growth and development was more advanced for aged seed, plants from young and old seed responded very similarly to the drought and did not differ in drought sensitivity or ability to recover from drought. It was concluded that irrigation requirements of a potato crop were not modified by seed tuber age.