Anthracnose in the leaves of sorghum plants is caused by the fungus Colletotrichum sublineolum Hann. Kabát et Bub. (syn. C. graminicola (Ces.) GW Wils.), and is responsible for reducing the yield of grain and forage. The proper management of the mineral nutrition of the plant may be a mechanism for the control of anthracnose. Among the minerals used in disease management, silicon stands out for reducing the severity of the disease in various crops. Given the above, this study aimed to assess the severity of anthracnose in different sorghum genotypes when supplemented with increasing levels of silicon. To this end, experiments were carried out under both greenhouse and field conditions, where the sorghum genotypes DOW 1F305 and A9735R were supplemented with increasing levels of silicon (0, 500, 1000, 1500, 2000, and 4000 kg ha-1) and assessed for the severity of anthracnose. We evaluated the severity of the disease with a rating scale and then samples were collected for determination of the concentration of silicon in the leaves. After analyzing the results, it was concluded that there was a reduction in the severity of anthracnose in response to fertilization with silicon in both of the evaluated genotypes. Although genotype DOW 1F305 accumulated lower silicon levels in the leaves, it was more resistant to foliar anthracnose.
Colletotrichum sublineolum; Sorghum bicolor; Calcium and magnesium silicate
