By Leonardo Gottems, reporter for Agropages
Nematodes can make all cash crops infeasible, generating losses of more than US$3,000 per hectare in Brazil. The intensive use of the soil, the lack of crop rotation and the use of varieties without resistance are decisive factors for the proliferation of these worms that attack the plant roots and affect the water and nutrient absorption.
According to Leonardo Aquino, Doctor in Plant Breeding at the Federal University of Viçosa and professor of the areas of Vegetable Production, Soil Fertilization, and Plant Nutrition, nematodes became one of the main worries of potato and carrot production in Brazil. “They are widely disseminated in the major regions of these two crops – Southeast, Center-West and Chapada Diamantina (Bahia),” said Aquino.
The roundworms (Meloidogyne incognita) and the root-lesion nematode (Pratylenchus brachyurus) are the main species that affect crops in Brazil. The expert warned that if not be combated, these species will be capable of causing considerable losses. “When we talk about crop losses, it is some 20% on an average in carrots, but in some plantings, they will be completely destroyed by nematodes, and 33% in potatoes,” added Aquino.
The potatoes reached by the nematodes have limited growth and not much attractant visually to the market due to gill formation, and carrots present deformation of roots and branches. The recommendation of the expert is that the farmer stays attentive to the management system and a choice of crop area without a history of nematodes, besides opting for more resistant varieties to the plague. In the case that the problem already exists, the producer can make the nematode controlled with the use of chemical nematicides or biological.
In the field of pesticides, one alternative that presented results is the use of fluensulfone. This active ingredient presents a concept of “real nematicide”, not only for stopping plague action, but provoking its death. “Fluensulfone is highly efficient on the reduction of nematode population and presents as a potential tool for the plague management in several crops,” said João Giraldi, Marketing Manager of Products at Adama.
Deraldo Horn, Marketing Manager at Simbiose, defends the use of biological nematicides: “We do not yet have an efficient chemical control and resistant cultivars to this crop, which has a wide geographic distribution. With biotechnology, we achieve to protect the root system during the whole cycle, impeding that the nematodes attack the root system, so that we avoid the entrance of other root diseases. NemaControl, formulated by the Bacillus amyloliquefaciens bacteria, was the first biological nematicide produced in Brazil.”