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The edible Ruspolia differens (Orthoptera: Tettigoniidae) is a widely‐consumed insect in East Africa but surprisingly little is known of its host plant use in the field. We studied host plants used by non‐swarming R. differens for 15 months, in central Uganda. In particular, we assessed the use of host plant species with respect to host cover in the field and host parts used by R. differens, also recording their sex, developmental stages, and colour morph. Ruspolia differens were found on 19 grass and two sedge species and they were observed predominantly (99% of 20,915 observations) on seven grasses (namely, Panicum maximum, Brachiaria ruziziensis, Chloris gayana, Hyparrhenia rufa, Cynodon dactylon, Sporobolus pyramidalis, and Pennisetum purpureum). Ruspolia differens was most frequently observed on the most common grass of each study site but P. maximum, and S. pyramidalis were used more frequently than expected from their cover in the field. Furthermore, R. differens were observed predominantly on inflorescences (97% of feeding observations) and much less frequently on the leaves (3.0%), stems (0.1%), and inflorescence stalks (0.1%) of grasses and sedges. Host use was not independent of sex, developmental stage, or colour morph. Panicum maximum was the preferred host of the youngest nymphs of R. differens. Overall, our findings indicate that a continuous supply of diverse grass resources with inflorescences is necessary for the management and conservation of wild populations of R. differens. [ABSTRACT FROM AUTHOR]

Gaps created 10 years ago by clearing of conifer plantations in Kibale National Park, Uganda, still experience very little tree regeneration. We studied the arrested succession by examining the survival of Neoboutonia macrocalyx Pax in different sized canopy gaps. We examined whether Neoboutonia seedlings can survive in gaps, which the tree rarely colonizes naturally and whether survival is limited by the size of the canopy opening, herbaceous climbers or insect folivory. A total of 384 seedlings were planted in 24 gaps, and survival was monitored for 19 months. Survival was dependent on canopy openness, being lowest in small gaps and highest in large gaps. We found a significant negative relationship between survival and folivory and a positive relationship between survival and climber infestation. Because 53% of the seedlings survived, regeneration could be limited by seed dispersal, rather than high seedling mortality. However, considering its high survival rate in arrested succession gaps, Neoboutonia seems to have good potential for forest restoration. [ABSTRACT FROM AUTHOR]

Very little is known about Leptocybe invasa Fisher & LaSalle, a new fast-spreading alien pest infesting Eucalyptus in several countries. This study examined L. invasa infestation on Eucalyptus germplasms in different agroecological zones of Uganda. The incidence and severity of the pest infestation were higher in hotter and drier agroecological zones than in cooler and wetter zones. There were direct negative relationships between altitude and L. invasa infestation on Eucalyptus species. No infestation was observed on any Eucalyptus species in stands at altitudes ranging from 1938 to 2452 (the maximum encountered) m above sea level. Leptocybe invasa infestation occurred on all Eucalyptus species encountered ( Eucalyptus grandis, Eucalyptus camaldulensis, Eucalyptus saligna, Eucalyptus robusta), except Eucalyptus maidenii that escaped attack because it was located outside the ecological range of the insect. The incidence and severity of L. invasa infestation was generally higher on clonal hybrids E. grandis × E. camaldulensis than on E. grandis × Eucalyptus urophylla. Research on host germplasms, L. invasa biology and ecology, impact of the pest infestation and possible control strategies are suggested to facilitate the development of sustainable management strategies. [ABSTRACT FROM AUTHOR]

Despite their well-known role as pests, termites also provide essential ecosystem services. In this paper, we undertook a comprehensive review of studies on human-termite interactions and farmers' indigenous knowledge across Sub-Saharan Africa in an effort to build coherent principles for termite management. The review revealed that local communities have comprehensive indigenous knowledge of termite ecology and taxonomy, and apply various indigenous control practices. Many communities also have elaborate knowledge of the nutritional and medicinal value of termites and mushrooms associated with termite nests. Children and women also widely consume termite mound soil for nutritional or other benefits encouraged by indigenous belief systems. In addition, subsistence farmers use termites as indicators of soil fertility, and use termite mound soil in low-risk farming strategies for crop production. In the past, chemical control of termites has been initiated without empirical data on the termite species, their damage threshold, and the social, ecological, or economic risks and trade-offs of the control. This review has provided new insights into the intimate nature of human-termite interactions in Africa and the risks of chemical control of termites to human welfare and the environment. We recommend that management of termites in future should be built on farmers' indigenous knowledge and adequate understanding of the ecology of the local termite species. [ABSTRACT FROM AUTHOR]

Farmers growing Eucalyptus species in Uganda were interviewed using a pre-tested questionnaire to investigate their knowledge, perceptions and management of the Eucalyptus gall-forming wasp, Leptocybe invasa Fisher & LaSalle, with the aim of developing integrated management programme for the pest. Farmers were aware of, and concerned about, the gall problem on Eucalyptus, but the vast majority of them did not know the cause. Most farmers did not attempt to control the infestation because they did not know of suitable control methods and/or the cause of the problem. Farmers' control decisions were not influenced by their experience in cultivating Eucalyptus or their education level. Only 20% of 59 farmers interviewed had received advice on L. invasa, suggesting poor flow of information on tree pests to farmers. Nearly all farmers interviewed still wanted to plant Eucalyptus, and they saw the trees as a source of several products and services. Problems relating to the increasing emergence of alien insect pests in tropical forests, and challenges and strategies for effective management of forest pests in developing countries are discussed. [ABSTRACT FROM AUTHOR]

Background: Edible insects are a sustainable source of high-quality animal protein. Insect farming is gaining interest globally, particularly in low-income countries, where it may provide substantial nutritional and economic benefits. To enhance insect farming practices in Africa, new farming systems are being developed. However, knowledge on how to best promote uptake of these systems is lacking. This study aims to fill this gap by investigating the effectiveness of educational interventions in promoting insect farming for household consumption in Africa. Method: The study is designed as a multi-site randomized controlled trial to evaluate the impacts of agricultural training alone or in combination with nutrition education on the adoption of insect farming in Ghana, Kenya and Uganda. In each of the three countries, ninety-nine villages are randomly assigned to one of three arms: two intervention arms and a control arm with no interventions. Focusing on production (P), the first intervention arm covers agricultural training on insect farming combined with provision of insect production starter kits. Focusing on both production and consumption (PC), the second intervention arm involves the same intervention components as treatment P plus additional nutrition education. The impacts of the interventions are measured by comparing baseline and endline data collected one year apart. Primary outcomes are adoption of insect farming and consumption of the farmed insects. Discussion: Understanding the drivers and impacts of novel agricultural practices is crucial for transitioning to sustainable food systems. The current project is the first to investigate how educational interventions promote insect farming for household consumption in low-income countries. The results will contribute evidence-based knowledge to support sustainable development through insect farming in Africa. Trial registration: The protocol is registered in the American Economic Association registry for randomized control trials with registration number AEARCTR-0009996. Initial registration date: 02 September 2022, last updated 17 May 2023. [ABSTRACT FROM AUTHOR]

Background: Tamarindus indica L is one of the indigenous fruit tree species that traditionally contributes to food security and ecosystem stability in sub-Saharan Africa. We hypothesized that the indigenous people of Eastern Uganda have used T. indica for generations and developed practices that promote its conservation and therefore we expected that they possess an elaborate indigenous knowledge (IK) system and that most of them have planted the species. The aim of this study was to assess the influence of IK, attitudes and practices on the use and conservation of T. indica. Methods: A cross sectional survey was conducted in two districts purposively selected from the T. indica natural range. Focus group discussions, key informant interviews, semi-structured interviews and observation were used to collect data. Data was processed using qualitative analytical methods. Results: Tamarindus indica was highly valued by the majority of the population. Tamarindus indica was used for food, medicinal, cultural, social, environmental amelioration and income generation purposes. The population possessed a high level of IK about T. indica evidenced by 18 categories of uses and multiple modes of use. Fruit pulp was the most commonly used tamarind product. Relative frequency of citation of the different uses provides insight into usage levels and IK possessed. The communities' food and medicinal uses concurred with scientific reports of health benefits of consuming T. indica. Approximately half of respondents had T. indica on their compounds or homegardens (53%). Fifty two percent of the tamarind population was self-propagated, 45% were planted while the propagation history for the remaining 3% was not known. Constraints towards planting T. indica included limited land, long maturation period and low monetary value. Fifty three percent of those who were growing T. indica did not carry out any silvicultural practices. The majority of T. indica encountered (87%) was intercropped with other crops or trees. Several beliefs and taboos regarding T. indica persist. Conclusion: Tamarindus indica has a high use value in the study area evidenced by multiple uses. Indigenous knowledge and uses concurred with scientifically proven nutritional and medicinal attributes of T. indica in literature which is significant given current trends towards affordable functional foods. The high level of IK has not translated into high rates of planting T. indica. There is need to encourage value-addition so as to maximize T. indica benefits and enhance conservation. [ABSTRACT FROM AUTHOR]

Predicting the recovery processes in tree communities after logging is critical when developing conservation strategies. We assessed the patterns in tree communities in logged and primary forests in Kibale National Park, Uganda, representing 9- to 19-year-old clear-cuts of former conifer plantations, 42- to 43-year-old logged forests and primary forests. Species density and diversity were lower and dominance higher in the 9- to 19-year-old forests compared to the 42- to 43-year-old forests or primary forests. The tree species density, diversity and dominance of 42- to 43-year-old forests did not differ significantly from primary forests. However, they had a lower stem density, and higher cover of Acanthus pubescens, a shrub known to arrest the succession in Kibale. The tree community compositions of 9- to 19-year-old, 42- to 43-year-old and primary forests differed from each other. A large group of tree species (21) were primary forest indicators, that is, they were either missing or relatively rare in logged forests. The results of this study show that even after four decades of natural recovery, logged Afrotropical forests can still be distinguished from primary forests in their tree community compositions, emphasizing the slow community recovery and the important role of primary forests when preserving the tree communities in tropical rainforests. [ABSTRACT FROM AUTHOR]

The relative importance of host-plant resources, natural enemies or their interactions in controlling the population of galling insects and their parasitism is poorly known for tropical gallers. In this study, we assessed the impacts of plant quality and density of host trees in regulating the densities of a galler species, the cecidomyiid leaf galler (Cecidomyiini sp. 1EJV) and its parasitoids and inquilines on Neoboutonia macrocalyx trees in Uganda. We manipulated the nutritional quality (or vigour) and the resource concentration with four levels each of fertilization and the group size of host tree. We then recorded the effects of these treatments on the growth rate and total leaf area of host plants, the density of gallers and their mortality by parasitoids and inquilines. Higher levels of fertilization and host density resulted in significantly higher total leaf area than did ambient nutrient levels, and lowest tree densities, respectively. Fertilization also caused significant change in the growth rate of leaf area. Both higher fertilization and host density caused higher density of gallers. Total leaf area was positively associated with galler density, but within galled replicates, the galled leaves were larger than the ungalled leaves. Although highest levels of fertilization and density of host trees caused significant change in the densities of parasitoids, the rate of parasitism did not change. However, tree-density manipulations increased the rate of inquilinism, but on a very low level. Our results demonstrate a trophic cascade in the tropical galler and its parasitoids as a response to bottom-up effects. [ABSTRACT FROM AUTHOR]

The effects of bottom-up forces on the community structure of tropical insect gallers and within species variation in gall morphotype assemblages are not well understood., We tested the roles of increased nutritional quality and density of host plants with respect to structuring the galling insect communities and gall morphotype assemblages on Neoboutonia macrocalyx trees in Uganda., Plant nutritional quality and resource concentration were manipulated with four levels of fertilization and the group size of trees, respectively. After applying these treatments in May 2011, gallers established naturally on experimental replicates. Five months later, we sampled gallers and recorded their numbers and the different morphotypes. We analyzed the effects of treatments on the structures of galler communities and gall morphotype assemblages., We recorded 5237 individuals, representing four galler species. One species, Cecidomyiid leaf galler, was represented by three morphologically distinct galls. Fertilization, host tree density and their interactions significantly changed the structures of galler species communities and gall morphotype assemblages., The results of the present study demonstrate the important role of bottom-up factors in structuring galler communities and the gall morphotype assemblages. These changes are likely caused by differential responses of different galler species and gall morphs to plant quality or quantity changes. [ABSTRACT FROM AUTHOR]

Highlights: [•] Species richness, abundance and diversity increased and dominance decreased with age of restoration. [•] Similarity to primary forest communities increased with age of restoration. [•] Butterfly communities can recover in 40years, when primary forests are close by. [•] Differently aged forests were characterised by different butterfly specialists. [•] Tropical forest restoration enhances the rapid recovery of butterfly communities. [ABSTRACT FROM AUTHOR]

Termites are important decomposers and 'ecosystem engineers' in tropical ecosystems. Furthermore, termite assemblages are sensitive to human land-use intensification and often termite density and the importance of soil-feeding termites decrease with land-use intensification. These changes in termite assemblages may also lead to a decrease in termite-mediated ecosystem processes (e.g. soil formation, cellulose decomposition). We compared density and functional composition of termites with cellulose removal from undisturbed primary forests to farmlands (Kakamega Forest, Western Kenya). In contrast to the expectation, we found no response of termite abundance along the gradient of land-use intensification. However, as expected, the relative abundance of soil-feeders decreased from primary forests to farmlands. In contrast, frequency of attack on tissue paper baits and removal of tissue showed a clear hump-shaped relationship to land-use intensification with high values in secondary forests. These nonconcordant patterns of density and functional composition of termite assemblages with cellulose removal by termites suggest that it may be misleading to infer changes in a process by the characteristics of the assemblage of organisms that mediate that process. [ABSTRACT FROM AUTHOR]

The African edible bush‐cricket, Ruspolia differens (Serville) (Orthoptera: Tettigoniidae), is an economically valuable insect in sub‐Saharan Africa. For its mass‐rearing, suitable diets that can sustain its performance need to be identified. This study aimed at finding inflorescence diets of 10 host plant species and their mixtures that result in the highest R. differens production. We reared newly hatched nymphs to adults on inflorescences of single host species, and also on a gradient of five diversifying dietary mixtures consisting of one and mixtures of two, three, five, and seven host plant species. For the single host‐plant diets, the developmental time was shortest on Pennisetum purpureum, Chloris gayana, and Brachiaria ruziziensis (approximately 63 days), whereas the fresh weight was highest on B. ruziziensis and P. purpureum (approximately 0.383 g). Survival was highest (>65%) on C. gayana, P. purpureum, B. ruziziensis, Setaria sphacelata, and Sporobolus pyramidalis, and lowest on Panicum maximum, Hyparrhenia rufa, Cynodon dactylon, and Paspalum scrobiculatum (<40%). With respect to diet mixtures, the developmental time was significantly shorter (on average 16 days shorter), and survival was higher, in the most diversified diets compared to the least diversified diets. The contents of polyunsaturated fatty acids and fatty acid composition did not differ significantly among the diets. However, the content of monounsaturated fatty acids differed significantly among the diets and there was a significant diet*sex interaction. From the applied point of view, based on our results, for maximal weight and survival plus fast development, we recommend rearing on P. purpureum, C. gayana, B. ruziziensis, and S. sphacelata, and on dietary mixtures of inflorescences. These findings are important in designing large‐scale rearing programs for this species. [ABSTRACT FROM AUTHOR]

The edible Ruspolia differens (Serville) (Orthoptera: Tettigoniidae) is an important source of food in East Africa, but the seasonality of its population dynamics and host plant use are not fully understood. We studied seasonal patterns in the population density and relative frequency of developmental stages, sexes, colour morphs and host plants of the non‐swarming R. differens at two study sites in central Uganda over 15 months. Linear mixed models were used to study how precipitation and Enhanced Vegetation Index (EVI) predict population density and relative frequency of developmental stages, sexes, colour morphs and host plants. The results showed that all developmental stages of non‐swarming R. differens were found in the field throughout the year. The population densities of R. differens were high in wet seasons and low in dry seasons and were best predicted by the EVI of the previous month. The sex ratio of the non‐swarming R. differens populations was female biased. The proportion of males and green colour morphs increased during and after the rainy season. The use of host plants fluctuated seasonally so that during the greener seasons individuals used the more preferred host Panicum maximum more frequently. Overall, our work indicates that R. differens has a seasonal dynamic so that vegetation greenness can be used to forecast non‐swarming R. differens population densities. Our results also suggest that source populations for swarming individuals might have a local origin. This is important for the management of habitats for reproduction and conservation of viable populations of R. differens in East Africa. [ABSTRACT FROM AUTHOR]

Ruspolia differens (Serville) (Orthoptera: Tettigoniidae) is a highly valued edible grasshopper species in Africa. However, the effects of plant diets on lipid content and fatty acid composition of R. differens are not well understood. We tested the effects of four diets on the total lipid content and fatty acid composition of R. differens. Sixth instar nymphs of R. differens were reared on one, and mixtures of two, three, and six natural plant inflorescences. Individuals collected from the field constituted a control treatment. We extracted lipids and analyzed the fatty acid methyl esters using gas chromatography–mass spectrometry. We analyzed if the total lipid content, body weight, and fatty acid composition differed among diets and between the sexes using two‐way ANOVAs and a PERMANOVA model, respectively. The total lipid content and weight of R. differens did not differ among the diets. The nine common fatty acids were palmitic (mean across treatments, 26%), oleic (22%), palmitoleic (18%), linoleic (13%), stearic (7%), myristic (6%), myristoleic (4%), α‐linolenic (2%) and arachidic acid (1%). The composition of fatty acids and the proportion of essential fatty acids significantly differed among the diets. The proportion of essential fatty acids was highest in the control treatment (21%) but low in less diversified (one to three feed) diets (12–13%). This study demonstrates that the fatty acid composition in R. differens can be influenced through diet. Thus, with dietary manipulations, using local plants in Africa, it is possible to produce R. differens with preferred high quality essential fatty acids for human consumption. [ABSTRACT FROM AUTHOR]

Abstract: Ruspolia differens (Serville) (Orthoptera: Tettigoniidae, Conocephalinae) (its common names including ‘African edible bush‐cricket’, ‘edible grasshopper’, and ‘nsenene’) is an important source of food for humans in East Africa, but its ecology and biology are poorly understood. We explored the host plants of R. differens with a series of no‐choice and multiple‐choice laboratory experiments using 18 local common grass and sedge species in Uganda. In no‐choice experiments, the degree of acceptance differed significantly among the studied plant species, but in only three species were leaves rejected and in one species were inflorescences rejected. The pattern of acceptance among plant species was different in the local vs. swarming populations. Leaves were generally more accepted by the local population, whereas inflorescences were generally more accepted by the swarming population. Both leaves and inflorescences were more readily accepted by males than by females. According to the multiple‐choice experiments, R. differens preferred inflorescences over leaves. Our results demonstrate that R. differens is a facultatively oligophagous grass‐specialist, which has a clear preference for certain grass or sedge species (especially inflorescences), but it accepts many host plants if the preferred ones are not available. To preserve viable natural populations of R. differens in East Africa in the long term, our results draw special attention to the availability of grasslands where accepted and preferred host plants are available year‐round. [ABSTRACT FROM AUTHOR]

Abstract: The relationships between the physicochemical composition of Tamarindus indica pulp and seeds, and agro‐ecological zones and land use types were assessed in Uganda. The objective was to determine the relationship between the physicochemical composition, agro‐ecological zones, and land use types. The samples were processed by manually depulping the T. indica pods, sun‐drying the pulp and seeds, and grinding into powder. The powdered samples were analyzed for β‐carotenoids, vitamin C (ascorbic acid), calorific value, crude oil, acid, and peroxide values. Data were analyzed using ANOVA in the general linear model (GLM). Principal component analysis (PCA) was used to relate the physicochemical properties to the agro‐ecological zones and land use types. There were significant differences (p ≤ .05) in the physicochemical composition variables between agro‐ecological zones and land use types. Land use types showed strong correlations with physicochemical properties while agro‐ecological zones did not show correlations. The results show that in terms of general properties, T. indica pods provide a valuable, rich, and exceptional source of vitamin C, compared to many widely consumed indigenous and conventional fruits and vegetables. The pods from land use types characterized by natural habitats had relatively more nutrient levels than the land use types influenced by anthropogenic activities. [ABSTRACT FROM AUTHOR]

Mineral composition of dry Tamarindus indica LINN pulp and seeds was evaluated on samples collected from three different agro-ecological zones of Uganda (Lake Victoria Crescent, and Eastern and West Nile). The objective of the study was to evaluate the mineral composition of T. indica pulp and seed samples from across Uganda's different agro-ecological zones and land use types. Separately grounded samples of T. indica pulp and seeds were analyzed for Zn, Fe, Mg, P, Na, K, and Ca. The univariate analysis of variance in the General Linear Model was used to compare differences in mineral composition. Treatment means were separated using Least Significant Difference ( LSD) in Post Hoc Tests. The results showed that there were significant differences ( p ≤ 0.005) in mineral composition levels of T. indica pulp and seed samples between the different agro-ecological zones with the exception of P and Na (for pulp). The T. indica pulp and seeds samples from the Lake Victoria Crescent zone and wild land use type had generally higher mineral levels than T. indica samples from other agro-ecological zones and different land use types. As mineral composition levels were generally higher in the seed than the pulp samples, consumption of T. indica seeds should be promoted. There is also need to conserve individual species both on-farm and in the wild population, but T. indica mineral concentrations (both pulp and seeds) were higher in the samples from the wild population, making them good for human and animal diets. [ABSTRACT FROM AUTHOR]

Folk knowledge has been the basis for selection and improvement of many food crops such as potatoes, sorghum, yams, cassava and rice. In Uganda, there is strong potential to utilize folk knowledge to select and domesticate the shea butter tree (Vitellaria paradoxa C.F. Gaertn. subsp. nilotica (Kotschy) A.N. Henry & Chithra & N.C. Nair), an important economic tree species. Farmers report high variation in fruit yield, tree form and pulp taste. In this study, we documented shea tree folk classification by interviewing 300 respondents, 15 focus groups and 41 key informants across three farming systems of Uganda. Data were analyzed using Kruskall-Wallis and Spearman's tests, Chi-square, Multivariate, Factor and Discriminant Function Analyses. Folk classification and nomenclature of shea tree ethno-varieties is based on fruit/nut organoleptic (color and taste) and morphological attributes. Interestingly, despite the socio-cultural importance of shea oil, it does not feature as a factor in the folk classification and nomenclature of shea tree ethno-varieties. There was no significant difference in classification knowledge across the three farming systems (Kruskal - Wallis X2 = 28, df = 28, p > 0.05; Spearman's R > 0.8, p < 0.0001) although there was significant influence from ethnicity of the respondents (Pillai's trace = 0.817, p < 0.001). While this study provides a record of shea tree ethno-varieties and associated classification criteria, there is need to validate these 'ethno-varieties' using detailed morphological, biochemical and molecular analyses. [ABSTRACT FROM AUTHOR]

Abstract: Significant environmental benefits are claimed for local food systems, but these biophysical indicators are increasingly recognised as inadequate descriptors of supply chain ethics. Social factors such as health are also important indicators of good practice, and are recognised by the organic and local food movements as important to the development of rounded sustainable agricultural practices. This study compared the self-reported health status of farm workers in the United Kingdom, Spain, Kenya and Uganda who were supplying distant markets with fresh vegetables. Workers on Kenyan export horticulture farms reported significantly higher levels of physical health than did Kenyan non-export farm workers and workers in the other study countries. Mean health levels for farm workers in the United Kingdom were significantly lower than relevant population norms, indicating widespread levels of poor health amongst these workers. These results suggest that globalised supply chains can provide social benefits to workers, while local food systems do not always provide desirable social outcomes. The causal mechanisms of these observations probably relate more to the social conditions of workers than directly to income. [Copyright &y& Elsevier]

1. Exchange of carbon dioxide (CO2) from soils can contribute significantly to the global warming potential (GWP) of agro-ecosystems. Due to variations in soil type, climatic conditions and land management practices, exchange of CO2 can differ markedly in different geographical locations. The food industry is developing carbon footprints for their products necessitating integration of CO2 exchange from soils with other CO2 emissions along the food chain. It may be advantageous to grow certain crops in different geographical locations to minimize CO2 emissions from the soil, and this may provide potential to offset other emissions in the food chain, such as transport. 2. Values are derived for the C balance of soils growing horticultural crops in the UK, Spain and Uganda. Net ecosystem production ( NEP) is firstly calculated from the difference in net primary production ( NPP) and heterotrophic soil respiration ( Rh). Both NPP and Rh were estimated from intensive direct field measurements. Secondly, net biome production ( NBP) is calculated by subtracting the crop biomass from NEP to give an indication of C balance. The importance of soil exchange is discussed in the light of recent discussions on carbon footprints and within the context of food life-cycle assessment (LCA). 3. The amount of crop relative to the biomass and the Rh prevailing in the different countries were the dominant factors influencing the magnitude of NEP and NBP. The majority of the biomass for lettuce Lactuca sativa and vining peas Pisum sativum, was removed from the field as crop; therefore, NEP and NBP were mainly negative. This was amplified for lettuces grown in Uganda (−16·5 and −17 t C ha−1 year−1 compared to UK and Spain −4·8 to 7·4 and −5·1 to 6·3 t C ha−1 year−1 for NEP and NBP, respectively) where the climate elevated Rh. 4. Synthesis and applications. This study demonstrates the importance of soil emissions in the overall life cycle of vegetables. Variability in such emissions suggests that assigning a single value to food carbon footprints may not be adequate, even within a country. Locations with high heterotrophic soil respiration, such as Spain and Uganda (21·9 and 21·6 t C ha−1 year−1, respectively), could mitigate the negative effects of climate on the C costs of crop production by growth of crops with greater returns of residue to the soil. This would minimize net CO2 emissions from these agricultural ecosystems. [ABSTRACT FROM AUTHOR]

Objectives: To develop successful mass-rearing programs of edible insects, knowledge of the feeds and their influence on nutritional content is critical. We assessed the influence of natural food plants (grass inflorescences) and their mixtures on fatty acid profiles of edible Ruspolia differens. We reared neonate nymphs to adult on six dietary treatments consisting of one, and mixtures of two, three, five, six and eight plants. Results: The contents of saturated, monounsaturated and polyunsaturated fatty acids, omega-6/omega-3 ratio, and adult body weight did not differ among dietary treatments. However, the composition of fatty acids differed significantly among insects fed on six dietary treatments, but only for the rare fatty acids. Our results demonstrate that even if natural diets (grass inflorescences) do not strongly modify fatty acid contents or compositions of R. differens, when reared from neonate nymphs to adults, their n − 6/n − 3 fatty acid ratio is generally low and thus good for a healthy human diet. [ABSTRACT FROM AUTHOR]