Avaliação da parte aérea de variedades de mandioca in natura e fenada

Abstract

This study aimed to evaluate the production potential and nutritional value of the plant and hay from different shoots fractions of four cassava varieties grown in the North of Minas Gerais. The experiment was carried out at Experimental Farm UNIMONTES, located in Janaúba district. A randomized complete block design was used, with factorial scheme 4 x 3, with four replications and four cassava varieties (“Amarelinha”, “Olho Roxo”, “Periquita” and “Sabará”) and three forms of exploitation of cassava shoot (Entire Plant, Superior Third, Remains of Planting). During the collection of the fresh material, were made evaluations of plants height and yield of fresh forage and hay. Soon afterwards the material was taken to laboratory so that were made chemical and sensorial analyses. The data were submitted to variance analysis and their means were compared by Scott & Knott test at 5% significance level and by the P test (contrasts). The whole plant fraction from “Periquita” variety stood out as for hay and forage yield. The superior third fraction showed the best results as for leaf/stem and sensory analysis. For nutritional value of fresh material, “Sabará” variety presented a higher total digestible nutrient content and together with the “Periquita” a low lignin value, a smaller fraction C content in the protein fractionization and greater fraction B2 content of carbohydrates. The values of total digestible nutrients were similar for the different shoot fractions and the fraction whole plant stood out as for total carbohydrates content and as for the smallest lignin content. For the nutritional value of the hay the variety “Amarelinha” presented the smallest losses due to the low lignin content and fraction C of carbohydrates and together with the variety “Olho Roxo”, they presented high values of total digestible nutrients and a better distribution in the fibrous carbohydrates and no fibrous content. The fraction superior third presented the largest crude protein and lowest lignin and fraction carbohydrates C content.