IRRIGATION AND MULCHING MANAGEMENT FOR SWEET PEPPER CROP IN PROTECTED ENVIRONMENT

IRRIGATION AND MULCHING MANAGEMENT FOR SWEET PEPPER CROP IN PROTECTED ENVIRONMENT Antonio Evaldo Klar1; Sidnei Osmar Jadoski21Rural Engineering Department, Agronomic Science College,Paulista State University , Botucatu-SP (Brazil), klar@fca.unesp. br2Agricultural and Veterinarian Sciences Center, Guarapuava – PR. 1 ABSTRACT This study was developed over the 1999-2000 agricultural years at the Rural Engineering Department of School of Agronomical Sciences, UNESP, Botucatu, SP, under protected environment. The objective was to evaluate the influence of irrigation and black polyethylene mulch management on the water use and fruit production of sweet pepper crop (Capsicum annuum L., Elisa Hybrid) 230 days after seedling transplant (DAST). The study was divided into two experiments: 1) application of the irrigation at -50 and -1500 kPa minimum soil water potentials with and without mulching on the soil, from 29 to 168 DAST. A randomized experimental design was used with six replications; and 2) severe water deficit in the soil through irrigation suspension and mulching removal (169 to 230 DAST). Drip fertigation was used and soil water was monitored by tensiometers and neutron probe. It was verified that: - the severe drought stress caused leaf senescence and abscission and significantly affected the production and quality of sweet pepper fruits and the Water Use Efficiency (WUE); - the fruit yield and number were higher in the treatments with mulching, therefore polyethylene mulching showed to be an efficient technique to reduce irrigation number and water volume applied. This efficiency was reduced with soil water content decreases based on fruit yield. Pepper plants showed good osmotic adjustment and, consequently, tolerance to water stress. KEYWORDS: drought stress, polyethylene mulching, soil water potential KLAR, A. E. ; JADOSKI, S. O. IRRIGACAO E COBERTURA MORTA EM PLANTAS DE PIMENTAO EM AMBIENTE PROTEGIDO 2 RESUMO O trabalho foi desenvolvido no ano agricola 1999-2000, em casa de vegetacao, no Departamento de Engenharia Rural da Faculdade de Ciencias Agronomicas - UNESP, campus de Botucatu, SP. O objetivo foi estudar o efeito de diferentes manejos da agua de irrigacao e de cobertura de polietileno preto na superficie do solo sobre o consumo de agua e producao de frutos da cultura do pimentao (Capsicum annuum L, hibrido Elisa), por um periodo de 230 dias apos o transplante das mudas (DAT). O trabalho foi composto por dois experimentos: I) aplicacao dos manejos da irrigacao a 50 kPa e 1500 kPa, com e sem a presenca de cobertura de polietileno preto sobre a superficie do solo, para o periodo de 29 a 168 DAT. O delineamento experimental foi inteiramente casualizado com seis repeticoes, e II) aplicacao de deficiencia hidrica severa no solo, atraves da suspensao das irrigacoes e retirada da cobertura de polietileno do solo, no periodo de 169 a 230 DAT. Concluiu-se que a deficiencia hidrica afeta a qualidade e a producao dos frutos do pimentao. A utilizacao de cobertura de polietileno sobre o solo e tecnica eficiente para reduzir a necessidade de irrigacoes e o volume de agua a ser aplicado aos cultivos e sua eficiencia e reduzida na medida em que diminui o conteudo de agua do solo. Houve significativa influencia no ajuste osmotico pela aplicacao dos estresses hidricos nos tratamentos em que o potencial minimo de agua no solo atingiu 1500 kPa. UNITERMOS: deficiencia hidrica, potencial de agua do solo, polietileno preto