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Omnivorous insects make foraging decisions between plant and prey resources depending on their accessibility, availability, and nutritional value. This shapes the stability and complexity of food webs, but also pest control services in agroecosystems. The mirid bug Lygus pratensis is a common cotton pest in China, but it also feeds on a variety of prey species. However, little is known about how different types of available resources affect its fitness and foraging behaviour. In laboratory experiments, we measured the fitness (survival, longevity and fecundity) of L. pratensis fed with bean pod only, bean and Aphis gossypii nymphs, or bean and Helicoverpa armigera eggs, and we also conducted focal observations of its foraging behaviour when provided the latter two. Adding H. armigera to its diet increased its fitness (both survival and fecundity), while adding A. gossypii was marginally detrimental. The different diets did not affect the time spent walking (searching for food resources) or preying, but significantly affected the time spent sapping bean tissue depending on L. pratensis life stage. Nymphs spent more time sapping plant when provided with H. armigera than A. gossypii (possibly through higher efficiency of handling prey). In addition, adults spent less time sapping plant than did nymphs (possibly through good efficiency of handling A. gossypii mobile prey and due to higher protein requirements). This special case of life-history omnivory highlights the complexity of natural food webs, where a major crop pest at the juvenile stage may become a biological control agent at the adult stage. [ABSTRACT FROM AUTHOR]

Sichuan pepper (Zanthoxylum bungeanum, HJ), a spice widely used in China, has antioxidative, anti-inflammatory, antibacterial, and anti-obesity properties. In this study, to confirm the value of HJ as a functional food, the in vitro antioxidant and bile acid-lowering capacities, as well as the effects on caecal microbiota, were compared with those of cumin (Cuminum cyminum, CM) and coriander (Coriandrum sativum, CR) seeds in Institute of Cancer Research (ICR) mice fed a high-sucrose and low-dietary fibre diet. The total phenolic content, superoxide anion radical-scavenging capacity, and Fe-reducing power of the HJ aqueous solution were higher than those of CM and CR (p < 0.05). The bile acid (taurocholic, glycocholic, and deoxycholic acids)-lowering capacity of the HJ suspension was also higher than those of CM and CR. Compared with mice fed a control diet (no fibre, NF), caecal Lactobacillus gasseri- and Muribaculum intestinale-like bacteria were higher in mice fed a diet containing 5% (w/w) of CM, CR, or HJ for 14 days. Bifidobacterium pseudolongum-, Lactobacillus murinus/animalis-, and Faecalibaculum rodentium-like bacteria were significantly increased, while Desulfovibrio-like bacteria were significantly decreased in the HJ group. In addition, CM and HJ may benefit specific metabolic functions of gut microbiota, such as starch, sucrose, and tyrosine metabolism. The tumour necrosis factor (TNF-α) concentration in the spleen tissue of ICR mice was decreased by the intake of spices. However, there were no changes in interleukin-2 (IL-2) and IL-10 levels in HJ fed mice. These results suggested that HJ has potential as a functional food related to gut microbiota. Key points: • Bididobacterium and Faecalibaculum in mice gut microbiota are increased by Sichuan pepper (HJ). • Desulfovibrionaceae, an inflammatory LPS producer, in mice gut microbiota is decreased by HJ. • HJ decreases pro-inflammatory TNF both in murine spleen tissue and in vitro macrophages. [ABSTRACT FROM AUTHOR]

Background and aims: Understanding the variability in water availability in agroforestry systems in rain-fed orchards is vital for optimizing orchard management in semiarid areas. However, few studies have examined the soil capacity of water stock and supply in these systems over multiple years. We aim at (i) characterizing several soil physical properties related to water availability and inter-annual dynamics of soil water content and (ii) exploring their response to meteorological conditions and root distribution. Methods: Jujube (Ziziphus jujuba Mill.) intercropped with the fodder species canola (Brassica napus L.) (JFCS), jujube intercropped with daylily (Hemerocallis fulva L.) (JDLS), and a jujube orchard with clean tillage (JCS) were established on the Loess Plateau, China. Soil physical properties (including soil bulk density, soil hydraulic conductivity, soil field capacity, and soil porosity), soil water content and fine root data were collected over the period 2014–2017. Results: Compared to JCS-Tree, the field capacity was significantly increased both in the JFCS-Tree and JDLS-Tree treatments, while soil capillary porosity increased significantly only in the JFCS-Tree. Compared to JCS-Inter-row, the JFCS-Inter-row and JDLS-Inter-row exhibited significantly decreased soil bulk density, and increased field capacity, saturated hydraulic conductivity, and improved soil porosity, but the non-capillary porosity in the JDLS-Inter-row treatment were not significantly modified. Compare to JCS-Tree treatment, the soil water at 0–60 cm significantly increased under JFCS-Tree and JDLS-Tree in four years. However, due to the deeper fine root distribution for both tree and crop under JDLS-Inter-row, the soil water content at 60–180 cm in JDLS-Inter-row significantly decreased more than JFCS-Inter-row and JCS-Inter-row. Conclusions: The introduced crop modified the soil physical properties and soil water content, indirectly under trees and directly between inter-rows through the role of fine roots, thereby changing the orchard environment in semiarid areas. Agroforests can generally improve water condition at shallow soil layers compared to monocultural plantations, although such an effect may be accompanied with lower water stock at deeper soil layers in inter-rows, depending on crop species chosen. [ABSTRACT FROM AUTHOR]