Agronomic Compatibility of the Potato (Solanum tuberosum L.) Intercropped with Onion (Allium fistulosum).

Abstract

The system of intercropping potato with onion is a production alternative for Nariño (Colombia) potato growers and a defense against low crop productivity. A trial was carried out in which the potato variety Parda Pastusa was intercropped with onion variety Blanca Common, this was done at three planting dates and a three onion sowing densities, in order lo evaluate its effect over potato yield, tuber size and Premnotripes vorax Hustache. The economic benefits of different systems arrangements were evaluated, that is the relative competition index of each crop, as well as the land efficiency use (U. E. T.). Onion did not affect the potato yield, nor tuber size at the distance of 40, 80 or 120 cm within the potato row. The onion plant did not controll the "gusano Blanco" when simultaneously planted, or when planted during the first or second hilling. The monoculture of potato with three applications of an insecticide having as chemical basis carbofuran, gave effective control of the pest and a higher return as compared to intercroppings. The greatest U. E. T. was obtained from potato-onion intercropping when sowed simultaneously at a distance of 40 cm between plants.

Aditional Index Words: Intercropping, Solanum tuberosum L., Allium fistulosvm, land efficient use, ratability, tuber size, competing.