Abstract

RODRIGUEZ-AMAYA, Ricardo et al. Morphological characterization of pipiana squash (Cucurbita argyrosperma Huber). Agric. Téc. Méx [online]. 2009, vol.35, n.4, pp.379-389. ISSN 0568-2517.

The pipiana squash (Cucurbita argyrosperma Huber) lacks formal descriptors of their existent morphological diversity in Mexico. With this antecedent and regarding the importance of conserving and to describe the genetic resources of this species, a research was carried out with the aim of characterizing 32 accessions of pipiana squash from the gene bank of the Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias, at Campo Experimental Bajio, Mexico during the spring-summer cycle (2006). Seedlings of the 32 populations were distributed in the field under a complete random block design, and the agronomic handling was carried out according to the techniques used for commercial squash production in the "Bajio Guanajuatense" of Mexico. For the characterization, two sets of descriptors were used, one set included 37 qualitative traits and a second set of 13 quantitative traits; traits were recorded during the cultivation cycle and at post harvest. Data handling included principal components and clusters analysis. In the qualitative traits the distribution of the tertiary color, intensity of spots, color of the margin and seed coat plus the form of the leaf border, showed large variation in the evaluated accessions, these traits influenced the formation of seven groups of accessions. Meanwhile, the quantitative traits weight of one hundred seeds with and without coat, fruit weight and days to flowering contributed more to the distinction of the characterized accessions, separating them in five groups. The characteristics of anthropocentric interest, weigh of a hundred seeds with and without coat, showed the most diversity in the germplasm of pipiana squash.

Keywords : accessions; characterization; genetic resources; principal components.