Managing Pratylenchus brachyurus in agricultural integrated systems using the tropical forage legume 'Estilosantes Campo Grande’ in Brazil
Celso Fernandes: Embrapa
<div>Losses caused by <span><em>Pratylenchus brachyurus </em></span>(Pb) has become increasingly common in soybean, maize and cotton crops in Brazil, due to the use of crops in succession or rotation susceptible to the nematode. Currently, <em>Crotalaria</em> spp. has been the main choice of resistance to Pb. This study aimed to evaluate the h<span lang="en">ostability </span>of the forage legume ‘Estilosantes Campo Grande (ECG)’, a multiline composed of improved genotypes of <em>Stylosanthes</em> <em>capitata</em> (Sc) and <em>S. macrocephala</em> (Sm) to Pb. Two trials were carried out at Embrapa Beef Cattle, Campo Grande-MS, Brazil. The first one was sown in pots containing Sc and Sm. After 30 days from emergence (DAE), 1000 specimens of Pb were inoculated and 90 days later, the number of Pb in the root mass and soil was assessed, and the reproduction factor (RF) was calculated. RFs ranged from 0.01 to 0.02 for Sc and Sm, respectively, compared to the soybean cultivar Vmax RR, with RF= 7.22. In another trial, Sc, Sm and the controls <em>Crotalatria spectabilis</em> and soybean Vmax RR were sown in a natural infested area, with a history of high Pb populations. After 90 DAE, the density of Pb in the roots mass of Sc and Sm behaved similarly to <em>C. spectabilis</em>, with 5.0, 0.0 and 17.5 specimens of Pb/10g of roots, respectively. For soybean Vmax RR, 3229 individuals of Pb were observed in the same root volume. Thus, ECG can be considered a bad host for this nematode, being an excellent option for the management of Pb in infested areas in Brazil.</div>
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