Blueberry root rot is a devastating disease of blueberries and poses a serious threat to the growth of blueberries. Biological control is a green control method for blueberry root rot and an important measure to ensure the production of organic blueberries. It plays an important role in improving the economic benefits of blueberry farmers.
The pathogen of blueberry root rot is caused by Fusarium oxysporum. Fusarium has a wide host range and can infect cotton, beans, cucumbers, grapes, Chinese medicinal materials, blueberries, and other crops, causing rhizomes to rot.
It can produce large conidia, small conidia, and chlamydospores. In harsh environments, Fusarium can survive in the form of chlamydospores and survive for a long time in the soil environment.
Pathogens usually overwinter on plants or in the soil in the form of large conidia, small conidia, chlamydospores, or mycelium.
With the increase of blueberry planting years, harmful organisms continue to multiply and accumulate in the soil. The chlamydospores in the soil as the source of infection are the main cause of the disease.
Biological Control of Root Rot
Although chemical control has a significant control effect on blueberry root rot, pathogenic bacteria are easily resistant to pesticides. The use of pesticides continues to increase, resulting in large-scale residues, posing a serious threat to people’s living environment.
Although chemical control has a significant control effect on blueberry root rot, pathogenic bacteria are easily resistant to pesticides. The use of pesticides continues to increase, resulting in large-scale residues, posing a serious threat to people’s living environment.
Excessive use of pesticides has sharply reduced the number of beneficial microorganisms in the soil and weakened the soil’s self-remediation ability. Therefore, technologies and methods that utilize beneficial microorganisms and microbial metabolites to effectively control crop diseases are welcomed by people.
Biological control has the characteristics of safety, long-lasting, high efficiency, safety to the environment, ecology, and human health, and especially can avoid a series of problems caused by pesticide residues, making biological control more and more important to all countries in the world.
Biocontrol Fungus
At present, the most commonly used biocontrol bacteria are Trichoderma, Paecilomyces lilacinus, and Arbuscular Mycorrhizal. Trichoderma not only has a parasitic effect on a variety of pathogenic fungi but also has a good preventive effect on the occurrence of diseases. The most common Trichoderma are: Trichoderma harzianum, Trichoderma viride, Trichoderma Corning, and Trichoderma echinosporum.
Paecilomyces lilacinus can not only form a significant nutritional competition with Fusarium, but also have a better inhibitory effect on the growth of Fusarium hyphae. The extracellular polysaccharides secreted by Paecilomyces lilacinus can obviously inhibit the growth of Fusarium oxysporum mycelium and the germination of spores, and the higher the concentration of polysaccharides, the stronger the inhibitory effect.
Arbuscular mycorrhizal fungi can coexist with plants and establish a reciprocal symbiosis relationship, which can enhance the plant’s resistance to Fusarium oxysporum. Arbuscular mycorrhizal fungi not only have a good effect on improving the nutrition of plant roots but also have a good inhibitory effect on pathogens around the roots, reducing the morbidity and mortality of plant hair.
Biocontrol Bacteria
The advantage of biocontrol bacteria is that they have a large number of species and numbers, which are abundant in the rhizosphere soil of the plant and the plant body. It has a wide range of action modes, which can affect pathogenic bacteria through competition, antagonism, parasitism, and induction of plant disease resistance. The rapid reproduction speed is conducive to occupying space and competing for survival. The main biocontrol bacteria currently used to prevent and control plant diseases are Bacillus, Agrobacterium, Pseudomonas, Azotobacter, Erwinia, Serratia, Pasteurella.
In particular, Bacillus subtilis has a good control effect on blueberry root rot, and it also has a certain effect on increasing production. Bacillus subtilis has a fairly good control effect on root rot caused by Fusarium oxysporum.
Biocontrol Actinomycetes
Streptomyces is a type of actinomycete widely used in the biological control of plant diseases. Among them, Streptomyces roseaflavus, Streptomyces griseus, Streptomyces chlortetracycline, etc. have a very good inhibitory effect on wilt, root rot, and other soil-borne diseases.