Caracterización de selecciones de guayaba para el Bajío de Guanajuato, México

guava (psidium guajava l.) production and consumption in mexico is based on traditional varieties types "media china" and "peruana" among others. they were selected by farmers using the mexican germplasm available in the central semiarid region of mexico. the objective of this study was to characterize eight guava selections: seven with pink flesh and one of white flesh, developed by the horticulture program of the national research institute for forestry, agriculture and livestock (inifap). the study was conducted at the bajio research station, celaya, guanajuato, during 2007 and 2008. the selected trees were grown from seed obtained from an open pollinated collection of guava trees from brazil and mexico. the studied trees represented the second generation of individual selection. the plant characters studied were: vigour, phenology, tolerance to the disease locally known as "clavo" (pestalotiopsis psidii) and low temperatures. the fruit characters were: flesh color, weight, shape, seed content, titratable acidity, total solid content, c vitamin and lycopene. seven selections of pink flesh color were characterized, their ids are: 23-1, 26-8, 23-5, 25-5, 21-17, 22-11 and 25-9 and one with white flesh; 21-9. all pink selections show: large fruits, 118.4 to 207.6 g, produced from 6.5 to 34.7 kg per tree, its sugar content varied from 10.1 to 13.1 °brix, c vitamin from 83.29 to 185.75 mg 100 g and lycopene from 0.54 to 3.28 mg 100 g. its natural harvest season extended from september 1 to november 15. in comparison, "media china" shows a mean weight of 48 g per fruit, 11.6 °brix, 231.49 mg 100 g of c vitamin, 0.53 mg 100 g of lycopene and a natural harvest season from november to january. the studied selections can be a complement for the commercial varieties in terms of fruit type and harvest season. fruit characters observed in the selections compete with those of the commercial varieties.