Companion planting pattern of Salvia leucantha Cav. and Tagetes erecta
L. regulates population dynamics of natural enemies and pests in tea
plantation
Abstract
Biological control is an element of an integrated pest management
approach by restoring or maintaining biodiversity and associated
ecosystem services. Introducing flowering plants into crop management
may promote the top-down pest suppression by natural enemies and reduce
the reliance on pesticide use. Sage (Salvia farinacea Cav.) and marigold
(Tagetes erecta L.) were planted in tea gardens in this paper to
investigate the effect of sage and marigold, that of different layouts
on the pest and natural enemy populations in tea gardens. It was found
that sage and marigold, the checkerboard planting layout could
consistently increase the population of natural enemies such as spiders,
coccinellids, ladybird beetles, flower bugs, etc., and suppress the
population of major pests (aphids, thrips, whiteflies, etc.) in tea
gardens. At the same time, it was also found that the pests did not show
significant tropism when flower plants and tea trees were present
simultaneously, suggesting that flower plants may mask the ability of
the host plant to achieve protection of the target crop. Additionally,
the content composition of tea leaves, such as tea polyphenols and free
amino acids, was significantly improved in the treated area planted with
sage compared to the blank treatment group. Thus, it suggests that
planting sage and marigold in tea gardens are not only a good measure to
regulate the population density of natural enemies and pests, but also
can have a positive impact on tea quality.