Farm Table says:
Soil application of Trichoderma asperellum GDFS1009 granules promotes growth and resistance to Fusarium graminearum in maize
What is the problem?
Fusarium (Fusarium graminearum), a common pathogenic fungus responsible for stalk rot in corn, causes significant damage to corn crop through interference in nutrient uptake, slowing harvest, and infecting corn ears. Researchers from Ministry of Agriculture, Shanghai, investigated if it can be controlled by using soil applications of Trichoderma (Trichoderma asperellum GDFS1009 strain), which can be used as a fungicide.
What did the research involve?
- graminearum strains were isolated from stalk rot-infected maize stem tissues.
- Two of the strains were maintained as spore suspensions in 30% glycerol at –80°C and used to inocculate plant tissues in culture and in potted seedlings.
- Culture and greenhouse soil application tests of asperellum as a biocontrol agent against F. graminearum disease were conducted.
- In-vivo treatments were assessed in culture by comparing growth of Fusarium and Trichoderma grown together on a plate over 48, 72, 96 and 120 h time periods and comparing colony growth of the respective microbe colonies grown in isolation.
- In-vitro treatments were assessed by growing plants in field plots over three consecutive years where no Trichoderma had been applied to the soil, in plots were 75 kg ha–1 Trichoderma had been applied to the soil and in plots where 75 kg ha–1 Trichoderma and fertiliser had been applied to the soil . The plants were inoculated with Fusarium in the soil around the roots when the plants reached the 3-5 leaf stage.
- After 7-10 days, plant height, root length, and fresh weight were recorded and compared to negative control plants which had not been inoculated.
What were the key findings?
- The application of asperellum inhibited the mycelial growth of F. graminearium a rate of 60% in tissue culture and up to 53.7% in potted Zea maize seedlings.
- Height and growth of treated Zea maize plants also showed improvements compared to untreated control plants.
- The addition of fertiliser enhanced the benefits of plants treated with asperellum.
Where Trichoderma granules are applied to the soil over three consecutive seasons, significantly improved control of stalk rot was shown. In both the culture and the greenhouse tests, the T. asperellum appeared to out compete the F. graminearum for resources and reduced negative impact on the plant. According to He et al. (2019), an application of 45–75 kg ha–1 is recommended for the control of stalk rot when combined with 30 kg of NPK fertilizer at the sowing stage.
This paper was summarised by Luke Stafford (Bachelor of Biological Sciences with Honours – Botany and Genetics Majors (La Trobe University) and reviewed by Nickala Best (PhD Student (La Trobe University). Learn more about Luke and Nickala here.