Effect of Loose Kernel Smut caused by Sporisorium cruentum on Sorghum halepense. 2014. Astiz Gasso, M., Lovisolo, M., Perelló, A.

ASTIZ GASSO, M.; LOVISOLO, M; PERELLÓ ANALÍA

BIOCONTROL SCIENCE AND TECHNOLOGY

TAYLOR & FRANCIS LTD

Lugar: Londres; Año: 2014

0958-3157

The effects of the loose kernel smut fungus Sporisorium cruentum on its host Sorghum halepense were investigated through a series of in vitro and glasshouse-based experiments. Smut infection induced a decrease in the dry matter of rhizomes and aerial vegetative parts of the plant. The diseased plants reached lower height than controls. The infection resulted in multiple smutted buds that caused small panicles infected with the fungus. In addition, changes were observed in the structural morphology of the host. Leaf tissue sections showed hyphae degrading chloroplasts and vascular bundles colonized by the fungus. Subsequently, cells collapsed and widespread necrosis was observed. The pathogen did not colonize the gynoecium until the tassel was fully developed. The sporulation process continued and produced the total disintegration of anthers and tissues that composed them. When panicles were extracted before emergence, fungal hyphae were observed on promordia. Then, histological sections of panicles showed fungal hyphae located in the parenchyma tissue and in the nodal area. The infection occurred in the floral primordium and not when the tassel was fully differentiated and without emerging from the flag leaf. Grains were replaced by sori surrounded by a thin membrane that usually broke before or after the emergence of the panicle. This result, together with the significant decrease observed in the dry matter rhizomes and seeds of S. halepense, suggests that S. cruentum could be considered as a biocontrol agent in the integrated management of this weed.