Planting period is the main factor for controlling maize rough dwarf disease

Abstract

Maize rough dwarf virus (MRDV) is one of the main yield-limiting factors of maize in the Mediterranean. However, knowledge about the interactions between the agroecosystem and the virus–vector–host relationship continues to be limited. We used multi-model inference to test a landscape-scale approach together with variables measured in the field, and we estimated the effects of early and late planting on MRDV incidence. The results revealed that the virus incidence increased by 3% when the planting was delayed, and this increase was coincident with the first peak of the vector population. The variables at the field and landscape scales with a strong effect on virus incidence were the proportions of grasses in adjacent crops, in uncultivated areas, and in edges close to maize plants. Grass plant cover in the edges also affected virus incidence, but these effects varied with the planting period. These findings provide new insights into the causes of MRDV incidence and may provide some guidance to growers to reduce losses caused by the virus. Among the recommendations to be prioritized are early planting, management of grasses at field edges, and non-overlapping cultivation of maize and winter cereals in the same area.

This study was funded by the Spanish Ministry of Economy, Industry and Competitiveness projects AGL2014-53970-C2-1-R, AGL2014-53970-C2-2-R and AGL2017-84127-R. GCO. was funded by the grant BES-2015-072378 and IB was funded by the grant BES-2015-075700 from the Spanish Ministry of Economy and Competitiveness.