EMERGENCY AND INITIAL DEVELOPMENT OF Cassia grandis L. f. PLANTS ACCORDING TO DIFFERENT SUBSTRATES

Atualmente, busca-se utilizar substratos constitu\ueddos, principalmente, de res\uedduos org\ue2nicos, a fim de diminuir os custos com aduba\ue7\ue3o qu\uedmica. Nesse sentido, o experimento teve como objetivo avaliar diferentes tipos de substratos para a emerg\ueancia e desenvolvimento inicial de pl\ue2ntulas de c\ue1ssia-rosa ( Cassia grandis L. f.). O experimento foi conduzido em casa de vegeta\ue7\ue3o do Departamento de Ci\ueancias Vegetais da Universidade Federal Rural do Semi\ue1rido (UFERSA), em Mossor\uf3 - RN, no per\uedodo de abril a maio de 2012. Os substratos utilizados foram: terra vegetal + palha de arroz (nas propor\ue7\uf5es de 1:1, 1:3 e 3:1), terra vegetal + p\uf3 de madeira (nas propor\ue7\uf5es de 1:1, 1:3 e 3:1), terra vegetal + fibra de coco (nas propor\ue7\uf5es de 1:1, 1:3 e 3:1), terra vegetal + casca de castanha-de-caju (nas propor\ue7\uf5es de 1:1, 1:3 e 3:1) e terra vegetal (testemunha). O delineamento estat\uedstico utilizado foi o inteiramente casualizado, com 13 tratamentos (combina\ue7\uf5es dos substratos), em quatro repeti\ue7\uf5es de 25 sementes e as m\ue9dias submetidas ao teste de Skot-knott (pr<0,05). Foram avaliadas as vari\ue1veis porcentagem e velocidade de emerg\ueancia, comprimento da parte a\ue9rea, comprimento de raiz e massa seca da parte a\ue9rea, massa seca da raiz e massa seca total. De acordo com os resultados, os substratos terra vegetal + p\uf3 de madeira (1:1) e terra vegetal + fibra de coco (1:3) foram os mais apropriados, proporcionando melhores resultados em emerg\ueancia, massa seca da parte a\ue9rea, comprimento da parte a\ue9rea, massa seca da raiz e comprimento da raiz. Por outro lado, verificou-se que o substrato composto com terra vegetal e casca de castanha-de-caju (1:3) mostrou-se inadequado para a emerg\ueancia de pl\ue2ntulas de c\ue1ssia-rosa.Currently, it is aimed to use substrates composed primarily of organic waste in order to reduce costs with chemical fertilizer. In that sense, the experiment was to evaluate different types of substrates for the emergence and early development of seedlings of Cassia grandis L. f. The experiment was carried out in a greenhouse at the Departament of Vegetable Sciences of Federal Rural do Semi-\uc1rido (UFERSA), in Mossor\uf3, Rio Grande do Norte state, Brazil. The substrates used were: sand + carbonized rice husk (in ratios of 1:1, 1:3 and 3:1), plant sand + wood dust (in ratios of 1:1, 1:3 and 3:1), plant sand + coconut fiber (in ratios of 1:1, 1:3 and 3:1), plant sand + chestnut bark (in ratios of 1:1, 1:3 and 3:1) and plant sand (control). The experimental design was a completely randomized design with 13 treatments (combinations of substrates), with four replications of 25 seeds and the means to test for Skot-knot (pr <0.05). We evaluated the following variables: plant emergence, emergence speed, plant height, root length and weight of the aerial part of the plant, root dry mass and total dry mass. According to the results, the substrate plant sand + sawdust (1:1) and plant sand + coconut fiber (1:3) showed higher values, providing better results in emergence, weight of the aerial part of the plant, length of the aerial part of the plant, root dry mass and root length. It was found that the substrate compounds sand plant and chestnut bark (1:3) is harmful to the emergence of seedling of Cassia grandis