Companion plants associated with kale increase the abundance and species richness of the natural-enemies of Lipaphis erysimi (Kaltenbach) (Hemiptera: Aphididae)

Abstract

The effects of intercropping of Brassicaceae with coriander (Coriandrum sativum), dill (Anethum graveolens), African marigold (Tagetes erecta) and calendula (Calendula officinalis) on the abundance, species richness and diversity of predators and parasitoids of Lipaphis erysimi have been assessed. The numbers of aphids, parasitized aphids and natural enemies were determined during two consecutive phases. The first period comprised the vegetative phase of companion plants up to the onset of flowering and the development of kale up to the start of harvesting, while the second period encompassed the late flowering of companion plants up to senescence and the complete harvesting phase of kale. The establishment of L. erysimi and its natural enemies during the first period was enhanced by the climatic conditions and the additional nutritional resources offered by companion plants. Over the complete 13 week period, the abundance of natural enemies in kale intercropped with African marigold, calendula, coriander and dill increased by factors of 3.1, 2.1, 2.0 and 1.6, respectively, compared with the kale monoculture, while species richness increased by 1.8-fold in kale/African marigold intercrop and by a factor of 2.7 in the other treatments. The predominant predators were Syrphidae larvae and Hippodamia convergens whereas the predominant parasitoid was Diaeretiella rapae. The diversity of natural enemies was similar in all crops owing to the high proportion of syrphids in relation to the other groups of insects. The improved resources offered by companion plants can be exploited in the conservative biological control of insect pests.

Parasitoids diversity in organic Sweet Pepper (Capsicum annuum) associated with Basil (Ocimum basilicum) and Marigold (Tagetes erecta )

“…In our experiment, it also acted as good attractive to parasitoids, as a higher quantity of parasitoids was found in the systems associated with basil (98 individuals) than in the monoculture (40 individuals). In the same way, the association with marigold provided an parasitoids increasing (130 individuals), as also found in plantations of onion (Silveira et al, 2009), garlic (Silva et al, 2012), lettuce (Haro, 2015), and kale (Silva et al 2016). Numerous past studies support that vegetable diversification increases the number of parasitoid looking for food, host, and shelter (Pereira et al, 2015).…”

White Mustard, Sweet Alyssum, and Coriander as Insectary Plants in Agricultural Systems: Impacts on Ecosystem Services and Yield of Crops

“…Introducing coriander into cropping systems can affect the abundance and diversity of predaceous soil surface arthropods [92]. Coriander intercropped with kale positively affected the overall abundance (increased by a factor of 2.0) and species richness (increased by a factor of 2.7) of Staphylinidae and Araneae compared to kale grown alone [93]. In contrast, coriander strips did not increase ecosystem service levels in mixed orchards in Portugal [94].…”