Department of Agriculture warns about the management and prevention of corn stunting and viruses

Corn diseases called stunting and viruses have caused significant damage to crops, especially in hot regions of Brazil, where the crop is grown in more than one crop per year. Among the technical recommendations recommended to combat these diseases is the control of corn tiguera (plants born spontaneously, from corn grains that were lost or from ears that remained in the harvested area).

“The control of corn tiguera must be carried out as early as possible, being a very important preventive measure, as it can harbor and multiply contaminated insect vectors (hoppers - Dalbulus maidis and aphids - Rhopalosiphum maidis), becoming a “green bridge” and source of inoculum for stunting and viruses for the next corn crops”, explains Sandro Lemos Parise, agronomist who is part of the CATI Grains Technical Group and responsible for the Casa da Agricultura de Cândido Mota (linked to CATI Regional Assis), emphasizing that, this year, in which significant volumes of rain were recorded in important regions of São Paulo that produce second-crop corn, there was a direct influence on the germination of these corn grains lost at harvest, which reinforces the importance and urgency of the Tiguera Zero Corn Campaign.  

According to IAC researcher Aildson Pereira Duarte, corn and soybeans - the main crops in Brazil today - are cultivated in succession, since off-season corn, after soybeans, accounts for ¾ of the total area of ​​this cereal (16 million of the 21 million hectares cultivated in the country). In São Paulo, cultivation also predominates in the second harvest after soybeans, occupying more than 500 thousand hectares, while around 300 thousand hectares are cultivated in the summer harvest. “This succession faces increasing challenges due to the increase in pests and diseases, given that the corn tiguera is a green bridge between one harvest and another. Furthermore, the survival of these insects and pathogens depends on the continuous presence of corn in the field, especially that of the leafhopper, which feeds and multiplies only on this grass. Therefore, late control of tiguera corn is one of the main causes of the widespread and recurrent occurrence, which characterizes a true epidemic of stunting and viruses in corn plants, compromising their productive potential”.

Therefore, through the Tiguera de Milho Zero Campaign, the Department of Agriculture intensifies its long-standing work of research and rural extension, aimed at the sustainable development of corn cultivation, which has great economic importance in the State of São Paulo, sharing with producers information and techniques to better combat diseases and adopt Good Production Practices.

“Among the measures adopted by SAA is the elaboration of technical recommendations prepared jointly by IAC, CATI and the Biological Institute, which, if adopted in a coordinated manner by farmers in producing regions, could reduce the losses of these diseases in corn, as well how to improve the economic and environmental sustainability of production, by reducing the spraying of chemical insecticides”, highlights Aildson Pereira.