INTRODUCTION

At present, potato production from true seed (TPS) has advantages in developing countries, where market quality is not too important. However, this technology might even be adopted by developing countries, if progenies with improved quality were available. At the Institute of Agronomy, University of Milan, the possibility of growing potatoes from true seed in Italy is being evaluated. It is well known that production of high quality seed tubers is difficult to achieve in Italy, because of unfavourable weather conditions; TPS technology could solve this problem, besides saving money and making crop establishment, storage and transport less of a problem.

MATERIAL AND METHODS

Four progenies selected by the International Potato Center (CIP) were studied: open pollinated DTO-28 and DTO-33, and hybrids Atzimba x R-128.6 and Atzimba x 7xy–1. A preliminary trial was carried out in the glasshouse. Seeds were sown on 4 April 1985 in two different substrates in peat pots; one substrate was prepared with peat and sand (1:1 v/v), the other one with peat and soil (1:1 v/v). Both substrates were fertilized with 100 mg N, 300 mg P2O5 and 100 mg K2O. A split-plot design with three replications was used. Seedlings at the 4 to 5 leaf stage were transplanted in the field, in ridges 75 cm apart.