Microbial soil organisms can likely be a new, environmentally friendly weapon against crop diseases invading Africa, scientists say.
In the past few years several trans-boundary pests and diseases like fall armyworm, tomato leaf miner and the tropical race 4 (TR4) banana disease, caused millions of dollars of crop damage. It is also threatening food security on the continent.
“Research from our labs in Auburn University has shown great potential in microbes for helping fight pests – and we have done some research on fall armyworms that are pests in turf grass,” says Dr Esther Ngumbi from the Department of Entomology and Plant pathology at the Auburn University in Alabama (AU), USA.
Ngumbi is a post-doctoral researcher on beneficial soil micro-organisms and their ability to help mobilise natural enemies in plants.
She says observations show plant growth was improved by microbial formulations which also provided protection against insects, drought and other climate extremes.
One of the beneficial microbes researchers at AU is studying, is beneficial soil bacteria/microbes, specifically plant growth promoting rhizobacteria (PGPR).
The PGRZ can aid plant growth by helping plants acquire resources like nitrogen, phosphorus and other essential minerals by balancing plant hormone levels, or by indirectly decreasing the effects of pathogens on plant growth and development.
The PGRZ acts as a bio control agent by releasing a substance toxic to the beet armyworm (Spodoptera exigua) and the fall armyworm, (Spodoptera frugiperda) and enhances the ability of plants to fight off plant-eating insects.
The microbes are also a welcome alternative to harmful chemicals which are frequently used against crop and livestock trans-boundary pests and diseases, and are a threat to environmental systems.