Localized irrigation reduces diseases caused by leaf wetness in plants

Brazil, according to IBGE data, until October 2021, is considered the world's largest producer and exporter of products such as soy, coffee and sugarcane. For results as expressive as these to occur, a balance of several factors is necessary, including the environment in which the crop is located, which must have ideal climate conditions for good crop development.

The environment is relevant, as it influences all stages of development, both of the pathogen and the host plant, in the various stages of the cycle of pathogen-host relationships, commonly known as the disease triangle.

The climate is part of the environmental variable and directly affects the incidence of diseases, through air temperature and leaf wetness. Experts list the duration of leaf wetness, characterized by the presence of free water on the leaf surface resulting from dew, rain or irrigation, as a major villain in the establishment of pathogens, as it allows the germination and penetration of fungi and bacteria. If one of the three factors in the disease triangle is controlled, the risk of infection is reduced.

In the São Francisco Valley, the combination of high temperatures and relative humidity favor the emergence of fungal diseases such as vine downy mildew (viticultural plasmopara), and by bacteria such as grapevine bacterial canker (Xanthomonas campestris p.v. Viticulture). These diseases require only a few hours of leaf wetness to start the infection process and subsequently cause severe damage to the leaves, branches and bunches of the vine, reducing production and causing damage for the next productive pruning.  

Aiming to reduce the ideal environmental conditions for the development of the pathogen, there is the tool of localized drip irrigation, which promotes the distribution of water and nutrients directly to the plant's root zone in a uniform manner. As a result, the environment beneath the grapevine tends to remain less humid compared to other irrigation methods, keeping the leaf surface free of water droplets from irrigation.

Therefore, managing the cultivation environment well through an irrigation system with these benefits tends to bring greater profitability per hectare and savings in water resources and inputs, as the crop will be cultivated in a microclimate favorable to its development and not that of a pathogen. undesirable.