Abstract

CORASPE-LEON, Héctor M; MURAOKA, Takashi; IDE FRANZINI, Vinicius  and  DO PRADO GRANJA, Newton. N and k in nutrient solution in the potato tuber seed production ¹. Agronomía Trop. [online]. 2008, vol.58, n.4, pp.417-425. ISSN 0002-192X.

The potato-seed, Solanum tuberosum L., is considered a fundamental factor to guarantee high productivity and good tuber quality in the potato crop. In spite of their importance and the great number of studies on the potato crop, under tropical conditions, investigations on the mineral nutrition in potato-seed in varieties for industrial use, as much in field as in protected conditions, are scarce. The hydroponics system production, already consecrated in diverse crops, has been shown as an alternative for the production of potato pre-basic seeds, due to increases in the productivity, reduction of production costs, and elimination of contami­nation for soil pathogens. The objective of this research was to evaluate the effect of N and K interactions in nutritive solution, on the production of potato seed. The experiment was carried out in greenhouse, in the Center of Nuclear Energy in the Agriculture (CENA), University of São Paulo (USP), Brazil, and we used in vitro material of the "Atlantic" variety. Five doses of N and K in a factorial arrangement (5 x 5), were established in a complete randomize block desing with three repetitions. There was positive interaction between nitrogen and potassium, which resulted in decrease of the loss of weight of tubers during the period of storage. With the combination of 12,65 and 7,03 mmol L^-1 of N and cause the K the lowest percentage of dehydration.

Keywords : Solanum tuberosum L; Mineral Nutrition; Nutrient Solution; Expanded Clay; Potato Seed.