Produção de tomateiro orgânico irrigado por aspersão e gotejamento, em cultivo solteiro e consorciado com coentro

Abstract

Production of organic tomatoes irrigated by sprinkler and drip systems, as single crop and intercropped with corianderThe efficient use of water and the environmental diversity are crucial to the balance and sustainability of the organic production system of tomatoes. The present study aimed to evaluate the organic production of tomato cultivated as a single crop and in consortium with coriander, under sprinkler and drip irrigation. The experiment was carried out at an organic production area on the Federal District of Brazil. The experimental design was randomized blocks with treatments arranged in a 2 x 2 factorial (two irrigation systems x two cropping schemes). No significant interaction between the both factors occurred, and there was no significant effect of the cropping scheme over the evaluated variables. Although the crop cycle has been reduced when tomato was drip irrigated, the fruit yield was not affected by the irrigation systems. The larger reduction in the stand of plants observed under sprinkler irrigation has been compensated by an increase in the number of fruits per plant, without a change on the fruit mass. The smaller volume of soil explored by the tomato roots associated with the higher incidence of South American tomato pinworm (Tuta absoluta) and mainly powdery mildew (Leveillula taurica) may have limited the yield of drip irrigated tomato. The fruit decay rate on sprinkle irrigated plants was twice the rate found on the drip irrigated system. 1969; Marouelli et al., 2005). Assim, a irrigação por aspersão pode acentuar a sobrevivência e a dispersão de vários patógenos em razão da água ser aplicada sobre a parte aérea das plantas. Por outro lado, o impacto das gotas de água pode agir na remoção de propágulos de alguns patógenos, como o oídio Oidium lycopersici e Oidiopsis sicula (Erysiphaceae), e no desalojamento de esporos fúngicos e de células bacterianas (Lopes et al., 2006).Os sistemas de irrigação por sulco e por gotejamento minimizam a incidência de várias doenças bacterianas foliares em tomateiro, por não molharem a parte aérea das plantas, mas favorecem as doenças causadas por patógenos de solo, especialmente em condições de drenagem deficiente (Marouelli et al., 2005; Lopes et al., 2006). Apesar de o gotejamento ser destacadamente o sistema de irrigação que possibilita maiores produtividades de frutos, o sistema por sulco é ainda um dos mais adotados no Brasil na produção convencional de tomate de mesa, principalmente devido ao seu baixo custo de implantação (Coletti & Testezlaf, 2003).Ao contrário da maioria dos produtores convencionais de tomate tutorado, a aspersão é, possivelmente, o método de irrigação mais utilizado por produtores orgânicos de tomate (Menezes et al., 2007). Isso ocorre especialmente como forma de controlar alguns insetos-pragas e doenças (Costa et al., 1998; Coelho et al., 2000). A aspersão pode reduzir a população de ácaros e de insetos-pragas, tais como a traça-do-tomateiro Tuta absoluta e alguns insetos vetores de viroses, devido ao impacto d...

Sprinkler and drip irrigation in the organic tomato for single crops and when intercropped with coriander

“…were not significantly affected by the treatments (Table 1). These results are in agreement with Branco et al (2010) and Marouelli et al (2011a), who also found no variation in the productivity of the organic tomato whether irrigated by drip or sprinkler. This differs however from studies conducted in conventional production systems, where the yield of the tomato irrigated by drip is typically greater than when irrigated by sprinkler (HANSON, MAY, 2004;MAROUELLI et al, 2003).…”

“…As for the system of cultivation, it was found that intercropping tomato with coriander did not significantly affect tomato yield, agreeing with Marouelli et al (2011a) who used the cultivar 'Pollyanna'. Thus, coriander may be a good choice for diversifying the cultivation system of the tomato, since besides presenting a low level of competition, as also observed by Medeiros, Sujii and Morais (2009), it provides the producer with extra income.…”

“…Marouelli et al (2011a) also found similar responses of the tomato cultivar 'Pollyanna', irrigated under different systems, when grown alone and when intercropped with coriander. ) were not significantly affected by the treatments (Table 1).…”

“…Among the vegetables produced under organic systems, the tomato (Solanum lycopersicum L.) is one of the most sought after by Brazilian consumers, as its production under conventional systems demands the intensive use of pesticides. However, there are great difficulties in cultivating the tomato under organic systems due to phytosanitary problems that this crop presents, this being one of the main factors that makes the cost of the organic tomato far superior to those produced under a conventional system (MAROUELLI et al, 2011a;SCHALLENBERGER et al, 2008).…”

“…Recent work (MAROUELLI et al, 2011a;MORAIS, 2009) has shown that the cultivation of coriander (Coriandrum sativum L.) intercropped with the tomato may reduce the population densities of tomato leafminer (Tuta absoluta (Meyr.) and whitefly (Bemisia tabaci Genn., biotype B).…”