Ângulo foliar e lâmina de irrigação afetam a qualidade das mudas florestais
Carregando...
Arquivos
Data
2017-03-29
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Estadual Paulista (Unesp)
Resumo
Em muitos viveiros, a experiência pessoal dos viveiristas é o principal método utilizado para determinar quando e quanto tempo irrigar. Os viveiros produzem diversas espécies simultaneamente numa mesma área. Entre as espécies, há muita variação na arquitetura foliar, especificamente nos ângulos foliares. A falta de conhecimento sobre a lâmina adequada e como os ângulos foliares afetam a interceptação e captura da água, limitam a eficiência da irrigação e, consequentemente, a qualidade das mudas florestais. Este estudo teve como objetivo avaliar se o ângulo foliar das mudas de nove espécies florestais nativas e as lâminas de água aplicadas no viveiro afetam a qualidade morfológica, fisiológica e nutricional das mudas; a fração de lixiviação e a condutividade elétrica da solução lixiviada; e a qualidade morfológica das plantas após o plantio em vaso. As avaliações foram realizadas ao final do ciclo de produção de cada espécie no viveiro, através das variáveis: altura da parte aérea, diâmetro do colo, massa seca aérea, radicular e total, índice de qualidade de Dickson, área de projeção da copa, conformação do sistema radicular, potencial hídrico foliar, índice SPAD, transpiração diária, teores dos pigmentos foliares clorofila a, b, carotenoides e antocianinas, fração de lixiviação, condutividade elétrica da solução lixiviada e acúmulo nutricional. A qualidade morfológica das plantas após o plantio em vaso foi avaliada em intervalos de 30 dias, durante 120 dias, através das variáveis altura da parte aérea e diâmetro do colo. Aqui mostramos que, nas espécies com ângulos foliares maiores, a aplicação de lâminas menores resulta em mudas com maior qualidade. Nas espécies com ângulos menores, é necessária a aplicação de lâminas maiores, exceto quando a área de projeção da copa é pequena. A partir desse conhecimento, o ângulo foliar poderá começar a ser adotado entre os critérios para agrupar as espécies no viveiro, a fim de que a irrigação praticada evite o desperdício de água e fertilizantes, bem como aumente a qualidade morfológica, fisiológica e nutricional das mudas florestais.
In many nurseries, the personal experience of nurseries is the primary method used to determine when and how much time to irrigate. Nurseries produce several species simultaneously in the same area. Among the species, there is much variation in foliar architecture, specifically in the leaf angles. The lack of knowledge about the proper water depth and how the leaf angles affect the interception and capture of water, limit irrigation efficiency and consequently seedlings quality. The objective of this study was to evaluate if the leaf angle of nine species of tree seedlings and the water depths applied in the nursery affect the morphological, physiological and nutritional seedlings quality; the leaching fraction and the electrical conductivity of the solution leached; and the morphological quality of the plants after planting in pot. The evaluations were performed at the end of the production cycle of each species in the nursery, through the following variables: height, stem diameter, shoot, root and total dry mass, Dickson quality index, crown projection area, conformation root system, leaf water potential, SPAD index, daily perspiration, leaf chlorophyll a, b, carotenoids and anthocyanins, leaching fraction, electrical conductivity of the solution leached and nutritional accumulation. The morphological quality of the plants after planting was evaluated at intervals of 30 days, during 120 days, through the variables height of and stem diameter. Here we show that, in species with larger leaf angles, the application of smaller water depths results in seedlings with higher quality. In species with smaller angles, it is necessary to apply larger water depths, except when crown projection area of seedling is small. From this knowledge, leaf angle can begin to be adopted among the criteria to group the species in the nursery, so that the irrigation practiced avoids the waste of water and fertilizers, as well as increase the morphological, physiological and nutritional tree seedlings quality.
In many nurseries, the personal experience of nurseries is the primary method used to determine when and how much time to irrigate. Nurseries produce several species simultaneously in the same area. Among the species, there is much variation in foliar architecture, specifically in the leaf angles. The lack of knowledge about the proper water depth and how the leaf angles affect the interception and capture of water, limit irrigation efficiency and consequently seedlings quality. The objective of this study was to evaluate if the leaf angle of nine species of tree seedlings and the water depths applied in the nursery affect the morphological, physiological and nutritional seedlings quality; the leaching fraction and the electrical conductivity of the solution leached; and the morphological quality of the plants after planting in pot. The evaluations were performed at the end of the production cycle of each species in the nursery, through the following variables: height, stem diameter, shoot, root and total dry mass, Dickson quality index, crown projection area, conformation root system, leaf water potential, SPAD index, daily perspiration, leaf chlorophyll a, b, carotenoids and anthocyanins, leaching fraction, electrical conductivity of the solution leached and nutritional accumulation. The morphological quality of the plants after planting was evaluated at intervals of 30 days, during 120 days, through the variables height of and stem diameter. Here we show that, in species with larger leaf angles, the application of smaller water depths results in seedlings with higher quality. In species with smaller angles, it is necessary to apply larger water depths, except when crown projection area of seedling is small. From this knowledge, leaf angle can begin to be adopted among the criteria to group the species in the nursery, so that the irrigation practiced avoids the waste of water and fertilizers, as well as increase the morphological, physiological and nutritional tree seedlings quality.
Descrição
Palavras-chave
Viveiro, Arquitetura foliar, Área de projeção da copa, Microaspersão, Lixiviação, Condutividade elétrica, Nutrição, Desenvolvimento após o plantio, Nursery, Leaf architecture, Crown projection area, Microsprinkler, Leaching, Electrical conductivity, Nutrition, Development after planting