Portal de Periódicos da CAPES

ÍNDICES DE EFICIENCIA DE GENOTIPOS DE PAPA ESTABLECIDOS EN CONDICIONES DE SECANO

2006; Chapingo Autonomous University; Volume: XII; Issue: 1 Linguagem: Inglês

10.5154/r.rchsh.2004.09.049

2007-4034

Rafael Mora-Aguilar, J. Ortíz-Cereceres, A. Rivera-Peña, M.C. Mendoza-Castillo, Ma. T. Colinas-León, Héctor Lozoya-Saldaña,

Plant Pathogens and Resistance

Five potato genotypes were established in rows separated by 90 cm and plants by 30 cm in Metepec, in the state of Mexico, during the rainfed season of 1996. During the 85 days after their emergence, at intervals of 7±1 days, five plants with complete genotype competition were harvested by genotype to determine the total biomass of the plants and their organs, and the total foliar area, with which different efficiency indexes were estimated. During the vegetative stage, the relative growth rate was 0.10 a 0.40 g·g-1·d-1, agreeing with the genotype and plant organ, later diminishing until becoming negative. The net assimilation rate and of economical net assimilation fluctuated between 0.01-0.10 and 0.001-0.017 g·cm-2·d-1, respectively when tuberation began, and between 0.21-0.57 and 0.035 a 0.054 g·cm-2·d-1 during full tuberation; in both cases the Alpha Norteña and C-771A11 genotypes were outstanding. Between development days 43 and 57, the growth rate of the crop increased up to 184 and 264-386 g·m-2·d-1 in the precocious and late genotypes, respectively, and later diminished. The maximum rate of biomass accumulation in the underground organs was from 239 to 306 g·m-2·d-1, in the underground organs in the genotypes of undetermined habits at 85 days after emergence. The harvest index fluctuated between 48 and 92 %, and had a greater expression in the genotypes Alpha, Norteña and C-771A11. The majority of the genotypes had a high total yield of tubercles per plant due to the high values of relative growth rate and the growth rate of the tubercles, as well as the net economic assimilation rate. The greatest yield of commercial tubercles (1017 a 1164 g·pta-1) was due to the higher number of commercial tubercles per plant.