Determinação da curva de crescimento da cratília (Cratylia argentea) (Desv.) Kuntze para estabelecimento do ponto de corte.

Abstract

This work aimed to develop the knowledge and techniques of using Cratylia (Cratylia argentea) for biomass produtction aiming supplying fodder for livestock. The literature review exposed the contradictions that animal husbandry faces in relation to food supply during periods of climatic stress. We also sought to present the benefits that the use of cratilia can provide in Brazilian and Latin American livestock. Intending to evaluate the growth profile and the chemical composition of Cratylia (Cratylia argentea), periodic pruning and evaluations were made in different plants. The experiment was conducted with Cratylia planted in two-line spacings of 2 and 3 meters between lines and 0,5 meters between plants. They were evaluated in a cycle of 126 days, cutting every 21 days and totalizing 6 assessments for each treatment. The bromatological composition (DM, CP, NDF, ADF) of the edible part and productivity were evaluated. The study was planned in a completely randomized design and the differences in spacing were compared by Fisher test (p<0,05). Variations over the days were evaluated using regression analysis. The models that had the best fit for productivity was exponential and logistic, whereas, for the bromatological composition it was Gompertz and polynomial. Plants with 3 meters spacing had higher individual production, but lower productivity. The spacing of 2 meters resulted in higher CP contents. The growth rate reduces as time goes by and it is suggested to prune from 86 days for 2 meters spacing and 91 days for 3 meters spacing. The spacing of 2 meters between lines is more suggested to use, because it is more productive and have higher CP contents. Both spacings presented values of PB, NDF, and ADF of 20.26, 60.29 and 40.63% for spacing 2 m and 18.97, 60.61 and 42.11% for spacing 3 m, respectively for 105 days of pruning. Pruning Cratylia after 105 days results in less productive use for both spacings.