Figures (1)  Tables (2)

    • Figure 1. 

      Interactions between intercropping and host plants. The influence of intercropping on the host plants mainly includes two factors. 1 Above-ground factors: pests and microclimate, such as temperature, humidity and light intensity. 2 Below-ground factors: soil nutrients, enzymes and microorganisms. There are complex material exchanges between host plants, intercropping plants and soil microorganisms. (a) Host plants absorb nutrients from the soil. (b) Soil microorganisms degrade humus in soil. (c) Signal communication between the roots of intercropping plants and the host plants. (d) Signal communication between the roots of host plants and soil microorganisms.

    • Tea plantation
      intercropping plant(s)      		Pest(s) and effectVolatiles/predatorsReference(s)
      Flemingia macrophyllaLeafhoppers are attractedVolatiles (cis-3-hexen-1-ol, cis-3-hexenyl acetate, nonanal and alpha-farnesene)[54]
      Lavandula pinnata L., Corymbia citriodora (Hook.), Tagetes erecta, Leonurus ArtemisiaLeafhoppers are repelledVolatiles (alpha-pinene, 1,8-cineole, thymol anisole, thymol, p-cymene, limonene and camphor)[52−54]
      Rosmarinus officinalis L., Catsia tora and Paspalum notatumLeafhoppers are controlledpredators (spiders, ladybirds, coccinellids, and lacewings, Anystis baccarum)[17, 52, 55]
      Chamaecrista rotundifoliaHerbivorous beetles, Thysanoptera or Geometridae are controlledPredators (Serangium japonicum, Pharoscymnus taoi, Cryptogonus postimedialis or parasitoids)[11, 56]
      Mentha haplocalyxGreen plant bugs are repelledVolatiles (unknown)[53]
      Red beanLeafhoppers and thrips are controlledPredators (Orius sauteri)[57]
      Rosmarinus officinalisEctropis obliqua are repelledVolatiles (Beta-myrcene, Gamma-terpinene,
      (R)-(−)- linalool, (S)-(−)-cis-verbenol,
      (R)-(+)-camphor, and (S)-(−)-Verbenone)      		[59]
      MaizeLeafhoppers and Trialeurodes vaporariorum are controlledVolatiles (unknown)[58]
      Acacia confusa Merr. treesHemiptera, Lepidoptera, and Coleoptera are controlledPredators (Araneida, Hymenoptera, Hemiptera)[60]

      Table 1. 

      Effects of different intercropping patterns on pests in tea plantations.

    • Tea plantation intercropping plant(s)Nutrients increased in intercropping patternsReference(s)
      SoybeanAmmonium N, Nitrate N, AP, OM, AK (flowering–podding or mature period of soybean)[13]
      ChestnutSOM, N, P and K[18]
      Stropharia rugosoannulataSOM, TN and AN[68]
      Osmanthus and MicheliaTN, TK, AN, AP and SOM[14]
      Loquat or citrus or waxberryAN, AP, AK and SOM (loquat) and AP, AK and SOM (waxberry) and AN, AP and AK (citrus) in top-, sub- and bottom-soil[16]
      PeanutTP, TK, AP and AK in top-, sub- and bottom-soil[9]
      WalnutAN, AP, AK and SOM[69]
      Vulpia myurosSOM, TN, alkali-hydrolyzed N, AP and AK[15]

      Table 2. 

      Effects of different intercropping patterns on soil nutrients.