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Soil composition and herbivory are two environmental factors that can affect plant traits including flower traits, thus potentially affecting plant-pollinator interactions. Importantly, soil composition and herbivory may interact in these effects, with consequences for plant fitness. We assessed the main effects of aboveground insect herbivory and soil amendment with exuviae of three different insect species on visual and olfactory traits of Brassica nigra plants, including interactive effects. We combined various methodological approaches including gas chromatography/mass spectrometry, spectroscopy and machine learning to evaluate changes in flower morphology, colour and the emission of volatile organic compounds (VOCs). Soil amended with insect exuviae increased the total number of flowers per plant and VOC emission, whereas herbivory reduced petal area and VOC emission. Soil amendment and herbivory interacted in their effect on the floral reflectance spectrum of the base part of petals and the emission of 10 VOCs. These findings demonstrate the effects of insect exuviae as soil amendment on plant traits involved in reproduction, with a potential for enhanced reproductive success by increasing the strength of signals attracting pollinators and by mitigating the negative effects of herbivory.

Edible insects have been proposed as a novel and sustainable source of protein and other essential nutrients for human consumption but nutrient absorption efficiency is still uncertain. We investigated zinc absorption from house crickets (Acheta domesticus) in a single-center and single-blinded cross-over study with children aged 24–36 months old in Kenya from September-November 2021. For this, children were randomized to consume two different experimental meals labeled with stable isotopes of zinc (Zn) at two different days, separated by a wash-out period of one month. Primary endpoints were the differences in amount of absorbed zinc (AZ) from maize-based meals enriched with intrinsically 67Zn-labeled house crickets (2.61 mg Zn, n = 28) in comparison with meals enriched with 68Zn (low-enriched: 0.90 mg Zn, n = 29); high-enriched: 3.24 mg Zn, n = 28) or with intrinsically 67Zn-labeled low-chitin cricket flour (2.51 mg Zn, n = 25), whereas the secondary endpoints were the differences in fractional zinc absorption. We found that AZ from meals with whole crickets (geometric mean: 0.36 mg; 95%CI: 0.30, 0.43) was 2.6 times higher than from low-enriched maize meals (0.14 mg; 0.11, 0.16; P < 0.001), while it was not different from low-chitin cricket flour meals. Absorbed zinc from both cricket meals was higher than that from high-enriched meals. No severe adverse side events were reported. We conclude that edible house crickets are a good source of well-absorbable zinc, and their increased consumption could contribute to the alleviation of zinc deficiency. This trial was registered at the Pan African Clinical Trials Registry as PACTR202104533831364. Zinc deficiency can impair child growth and development, and edible insects contain substantial amount of zinc. Here the authors report that edible house crickets are a source of well-absorbable zinc in a randomized crossover clinical trial in Kenyan children aged 24–36 months. [ABSTRACT FROM AUTHOR]

Purpose: The Farmer Field School (FFS) has been used to enable farmers to adapt their farming decisions according to the field situation. This paper explores the methodological state, challenges and lessons learned, of the FFS around the World. Design/methodology/approach: We used a 52-item questionnaire to capture issues of design, implementation and evaluation of the FFS. Completed questionnaires were received from 57 ongoing or recent FFS programmes. Data were analysed using descriptive statistics. Findings: FFS programmes have diversified, including multiple crops and livestock. Farmer involvement in the design and planning of interventions was found to be critical. FFS programmes increasingly relied on farmers as FFS facilitators. Short training duration for FFS facilitators raised concern about FFS quality. Even though mechanisms for monitoring and evaluation were mostly in place, capacity for data analysis and data utilization were a concern. Practical implications: Results highlight strengths and shortcomings in design, implementation and evaluation of the FFS. The information acquired can be used to support the quality of ongoing and future programmes. Theoretical implications: This research contributed to understanding that the educational foundations of the FFS should be reflected in programme design and evaluation. Originality/value: Many studies of the FFS exist, but this is the first global overview on how farmer field school programmes are carried out, with various lessons learned.

SUMMARY: Although plants harbor a huge phytochemical diversity, only a fraction of plant metabolites is functionally characterized. In this work, we aimed to identify the genetic basis of metabolite functions during harsh environmental conditions in Arabidopsis thaliana. With machine learning algorithms we predicted stress‐specific metabolomes for 23 (a)biotic stress phenotypes of 300 natural Arabidopsis accessions. The prediction models identified several aliphatic glucosinolates (GLSs) and their breakdown products to be implicated in responses to heat stress in siliques and herbivory by Western flower thrips, Frankliniella occidentalis. Bivariate GWA mapping of the metabolome predictions and their respective (a)biotic stress phenotype revealed genetic associations with MAM, AOP, and GS‐OH, all three involved in aliphatic GSL biosynthesis. We, therefore, investigated thrips herbivory on AOP, MAM, and GS‐OH loss‐of‐function and/or overexpression lines. Arabidopsis accessions with a combination of MAM2 and AOP3, leading to 3‐hydroxypropyl dominance, suffered less from thrips feeding damage. The requirement of MAM2 for this effect could, however, not be confirmed with an introgression line of ecotypes Cvi and Ler, most likely due to other, unknown susceptibility factors in the Ler background. However, AOP2 and GS‐OH, adding alkenyl or hydroxy‐butenyl groups, respectively, did not have major effects on thrips feeding. Overall, this study illustrates the complex implications of aliphatic GSL diversity in plant responses to heat stress and a cell‐content‐feeding herbivore. Significance Statement: The function of many metabolites in (a)biotic stress responses is still largely unknown. By integrating large‐scale metabolome and stress‐related phenome data into GWA mapping, we reveal that genes involved in glucosinolate biosynthesis have pleiotropic effects on the responses of Arabidopsis thaliana to heat stress and thrips infestation. [ABSTRACT FROM AUTHOR]

There is increasing evidence that host–parasitoid interactions can have a pronounced impact on the microbiome of host insects, but it is unclear to what extent this is caused by the host and/or parasitoid. Here, we compared the internal and external microbiome of caterpillars of Pieris brassicae and Pieris rapae parasitized by Cotesia glomerata or Cotesia rubecula with nonparasitized caterpillars. Additionally, we investigated the internal and external microbiome of the parasitoid larvae. Both internal and external bacterial densities were significantly higher for P. brassicae than P. rapae , while no differences were found between parasitized and nonparasitized caterpillars. In contrast, parasitism significantly affected the composition of the internal and external microbiome of the caterpillars and the parasitoid larvae, but the effects were dependent on the host and parasitoid species. Irrespective of host species, a Wolbachia species was exclusively found inside caterpillars parasitized by C. glomerata , as well as in the corresponding developing parasitoid larvae. Similarly, a Nosema species was abundantly present inside parasitized caterpillars and the parasitoid larvae, but this was independent of the host and the parasitoid species. We conclude that parasitism has pronounced effects on host microbiomes, but the effects depend on both the host and parasitoid species. [ABSTRACT FROM AUTHOR]