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rate of one kg per square metre significantly reduced the occurrence of Meloidogyne incognita

in tobacco plants [51].

6.1. Vermicompost tea in pest and disease management

In agriculture, the use of vermicompost tea is increasing due to its potential to manage the

diversity of air and soil-borne diseases (Table 5). With this in mind, liquid extracts of composts

are seen as alternative options to the use of conventional chemical fungicides and pesticides in
response to the growing need for agriculture and food protection for environmental

sustainability. The efficacy of compost tea may be different depending on differences in the
types of composts used, sources and preparation methods. However, it has been documented

that the most excellent results are obtained by applying aerated tea instead of still tea. This is
probably because dissolved oxygen favours microbial diversity and activity. In the last 10 years,

the application of vermicompost tea as a biocontrol agent has increased significantly. Mycelial

growth of Botrytis cinerea, Sclerotinia sclerotiorum, Rhizoctonia solani, Corticium rolfsii, and
Fusarium oxysporum was significantly inhibited by liquid extracts from vermicomposts. The

high potential of using vermicompost as a suitable substitution technique to control plant
diseases is pointed out. It is recommended that farmers apply these liquid solutions directly to

the leaves as a simple, cheap, and environmentally friendly plant protection method with high
yield potential. In a study investigating disease prevention potential of vermicast tea against

Phytophthora infestans on three varieties of tomato; it was revealed that vermicast tea reduced

the susceptibility of leaves, stems and fruits of tomato plants to diseases caused by
Phytophthora infestans [49].

Vermicompost teas have significant potential to kill or suppress pests. It is reported that
drenching of vermicast tea suppresses spider mite damage. By applying vermicompost tea, the

soluble phenolic compounds reach the plant and make the plant tissues unpalatable, thereby

disturbing survival and reproduction rate of pests [50]. It is reported that earthworms take-up
soil substances, swallow humic acids through their guts and finally excrete polychlorinated and

monomeric phenols into the final vermicast. Vast microbial communities and their activities in
vermicompost tea led to the release of nutrients in slow but balanced manner that reduces

nitrogen inputs, improves phenol content of plants, thus resulting in plant tolerance against pests
[52].

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