Aspectos morfológicos de acessos do gênero dioscorea

Abstract

The genus Dioscorea known as yams, whose rhizophores constitute a food with excellent nutritional characteristics, in addition to generating employment and income. The yam crops are concentrated in the Northeast region of Brazil and even in this region little is known about the diversity present in the genus Dioscorea. Based on this information, prospecting for accesses of Dioscorea spp. in crops located in the state of Alagoas, a collection of work was then established. Thus, this work aimed to evaluate some morphological aspects in accesses of Dioscorea spp. Initially, the accesses were cultivated in the experimental area of Embrapa Tabuleiros Costeiros, located in Rio Largo - AL. When the 12 Dioscorea spp. accesses were in the vegetative development, their characterization began, based on the individual evaluation of the plants using morphological descriptors, where 14 characters were evaluated, with five observations made on the leaves and nine related to the stem of the yam. From the data obtained in measurements and observations, a descriptive statistical and grouping analysis was carried out. The results regarding the stem descriptors indicate that there was little variation in the 12 accesses of Dioscorea spp., with 25% of the accesses having a purplish green color, 75% a green color and only accesse 7 has wings and spines. Regarding the leaves, 75% of the accesses have opposite leaves with a sagitate shape and 25% have alternate leaves with a chordate shape. Only accesses 4 and 5 exhibited three lobes, while the others have a single lobe on the leaves. All accesses had a green colored petiole. In the five quantitative characteristics evaluated, there was a range in values between accesses. There was the formation of four distinct groups with five, four, two and one accesse composing groups 1, 2, 3 and 4, respectively. The results obtained demonstrate the existence of variability between Dioscorea spp. accesses. However, for greater discrimination of accesses, other evaluations are necessary, with the characteristics of flowers and rhizophores.

Keywords: yam; diversity; germplasm.