CARACTERIZACIÓN DE LÍNEAS DE JITOMATE EN HIDROPONÍA * CHARACTERIZATION OF TOMATO LINES UNDER HYDROPONICS

Tomato (Lycopersicon esculentum L.) is an important horticultural crop in Mexico due to a large area planted and economic value. The objective of this study was to select lines that can be used as parents of hybrids on the basis of superior traits in pollen, flower, seed, fruit and seedling morphology. The research was conducted in Montecillo, Texcoco, State of Mexico. During 2003 the seed increase of 21 lines of tomato was carried out under an hydroponic system; in 2004 a trial with 16 lines selected from the 21 were utilized to carry out a morphological characterization under greenhouse and laboratory. Data on flower, fruit, seed and plants were analyzed by means of an ANOVA and a Tukey test (p 0.05), and for the data on pollen grains a Principal Component Analysis was performed. Results indicated differences among tomato lines in traits such as easiness for flower emasculation and in the efficiency for the production of pollen and seeds. The PCA separated the sixteen lines in five groups and out of six traits, the area and main axes length of pollen grains were choosen and could be used as a selection criteria to be used in breeding programs; lines 2-4, 8-9, 5-11, 8-12, 3-12, 3-6, 5-7 and 7-12 were selected as parents on the basis of high production of fruits, pollen and seed.