The development of custard apple flower bud under nitrogen and potassium nutrition/Desenvolvimento de botoes florais da pinheira em funcao da adubacao nitrogenada e potassica

• Published in: Revista Brasileira de fruticultura
• Main Authors: Souza, Ivan Vilas Boas, Sao Jose, Abel Reboucas, Da Silva, Jose Carlson Gusmao, Bomfim, Marines Pereira, De Jesus, Jecilene Silva
• Format: Journal Article
• Language: Spanish
• Published: Sociedade Brasileira de Fruticultura 01-03-2016
• Subjects: Brasil
• ISSN: 0100-2945
• DOI: 10.1590/0100-29452016507

The custard apple tree (Annona squamosa L.), has increased in cultivation due to good prices in the national market. However, there are few studies regarding the fruit's nutrition. The aim of this study was to verify the influence of N and K levels in developing the flower buds in two growing cycles, corresponding to the time of high temperatures (spring-summer) and another milder season (autumn-winter). The experiment was conducted in a rural property located in the municipality of Anage, Bahia, installed in a randomised complete block design with 3 blocks, arranged in a factorial 4 x 4, obtained by the combination of the following levels of N (0, 16.875, 33.750 and 67.500 g [plant.sup.-1]) in the form of urea and K (0, 22.5, 45.0 and 90.0 g [plant.sup.-1]) in the form of potassium chloride, applied every fifteen days (every fortnight / every two weeks). It was evaluated the vigor of floral buds, measured by determining its weight and the length of them. At the end of the study it was concluded that the vigor of the floral buds tended to increase with elevated levels of nitrogen in the coldest period of the year (dry season with low in temperature). In the spring-summer period (rainy season and high temperature) the vigor of the flower buds was reduced as they increased the doses of N. Potassium did not affect the vigor of the flower buds in these considered periods. There was no interaction between N and K levels for the vigor of the flower buds. Index terms: Annona squamosa L., Annonaceae, growth, nutrition, floral quality. A pinheira (Annona squamosa L.) tem seu plantio aumentado em detrimento dos bons precos alcancados no mercado nacional. Porem, existem poucos estudos sobre sua nutricao. O presente trabalho teve como objetivo verificar a influencia dos niveis de N e K no desenvolvimento de seus botoes florais em dois ciclos de cultivo, que corresponderam a epoca de temperaturas elevadas (primavera-verao) e outra mais amenas (outono-inverno). O experimento foi desenvolvido em propriedade rural localizada no municipio de Anage-BA, instalado no delineamento de blocos casualizados, com 3 blocos, arranjados num esquema fatorial de 4 x 4, obtidos pela combinacao dos seguintes niveis de N (0; 16,875; 33,750 e 67,500 g [planta.sup.-1]) na forma de ureia e K (0; 22,5; 45,0 e 90,0 g [planta.sup.-1]), na forma de cloreto de potassio, aplicados quinzenalmente. Foi avaliado o vigor dos botoes florais, medidos atraves da determinacao de sua massa e do comprimento dos mesmos. Ao final do estudo, pode-se concluir que o vigor dos botoes florais da pinheira tendeu a aumentar com a elevacao das doses de nitrogenio no periodo mais frio do ano (periodo seco com queda de temperatura). No periodo de primavera-verao (periodo chuvoso e de alta temperatura), ocorreu reducao do vigor dos botoes florais a medida que aumentaram as doses de N. O potassio nao afetou o vigor dos botoes florais da pinheira nas epocas consideradas. Nao houve interacao entre os niveis de N e K para o vigor dos botoes florais. Termos para indexacao: Annona squamosa L., Anonaceas, crescimento, nutricao, qualidade floral.