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Before the invasion of the fall armyworm (FAW) Spodoptera frugiperda into Africa, smallholder farmers had been using indigenous practices such as applying fish soup to plants to manage stemborer pests. Although farmers have since begun adapting this practice against FAW, no attempt has been made to scientifically evaluate this practice. Therefore, we assessed the efficacy of applying fish soup to maize plants that were artificially infested with FAW under semi-field conditions. Our results showed that foliar damage is inversely correlated with the concentration of a fish soup and sugar solution, with the highest (100%) concentration resulting in the lowest foliar damage and the highest plant recovery. The FAW foliar damage results for maize plants treated with 100%, 50%, 10% fish soup and sugar, and distilled water were 46.3 ± 5.6, 51.1 ± 5.0, 71.6 ± 5.2, and 99.4 ± 0.4%, respectively, whereas plant recovery results from the same treatments were 35.2 ± 3.7, 31.1 ± 5.4, 20.0 ± 4.6, and 0.0 ± 0.0%, respectively. A concentration of fish soup and sugar solution of at least 25.9% was required to achieve the lowest foliar damage of 17.8% and peak plant recovery of 73.6%. Fish soup and sugar solutions attracted a wide range of insects, including potential natural enemies (predators and parasitoids) of FAW, in a dose-dependent manner. Maize plants treated with fish soup and sugar showed higher chlorophyll content and better growth than the control did. Proximate and chemical analysis showed that fish soup contains essential plant growth nutrients (e.g., nitrogen, phosphorus, and calcium). Through GC-MS analyses, we identified 76 volatile organic compounds in fish soup, of which 16 have been reported as insect attractants, highlighting their potential ecological significance. Therefore, the indigenous pest management practices for FAW, such as the use of fish soup, deserve particular attention. These practices could contribute to food security and improve the livelihoods of vulnerable communities. Further field validation studies, economic analyses, product development, and optimisation are therefore required to optimise the use of fish soup based on fish waste.

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BACKGROUND: The fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith) is a serious pest of maize. Farming systems such as push-pull or maize-legume intercropping have been reported to reduce FAW infestations significantly. However, the exact mechanisms involved in FAW management have not been practically elucidated. We therefore assessed larval host preference, feeding and survival rate when exposed to four host plants commonly used in push-pull and legume intercropping. We also compared adult moths' oviposition preference between maize and other grasses used as trap crops in push-pull. RESULTS: The larval orientation and settlement study showed that maize was the most preferred host plant followed by bean, desmodium and Brachiaria brizantha cv Mulato II. The larval arrest and dispersal experiment showed that mean number of larvae was significantly higher on maize than on Desmodium or B. brizantha cv Mulato II. However, no significant differences were found between maize and bean after 24 h. Maize was the most consumed plant, followed by bean, desmodium and finally brachiaria. The mean percentage of survival to the pupation stage was significantly higher on maize. The study on FAW oviposition preference showed no significant differences in egg deposited between maize and other grasses. However, B. brizantha cv Xaraes, which received more eggs than maize, could be a promising alternative to B. brizantha cv Mulato II for the control of FAW. CONCLUSION: The study provides a better understanding of the mechanisms involved in the control of fall armyworm under the push-pull and maize legume intercropping. © 2021 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

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Malaria is still one of the greatest causes of mortality in the world; in Brazil there are over 500,000 reported cases each year. Malaria, caused by the protozoan Plasmodium, has been aggravated by the increasing resistance of Plasmodium to the traditional drugs chloroquine and mefloquine. The study of new drugs resulted in the identification of antimalarial activities of an endoperoxide sesquiterpene lactone, called qinghaosu or atemisinin, extracted from the leaves of Artemisinin annua L., of the Asteraceae family. The research work developed at MEDIPLANT (Switzerland) and CPQBA-UNICAPM (Brazil) involved the selection and breeding of genotypes rich in artemisinin and presenting high biomass followed by a second selection for adaptation to Brazilian climatic conditions. Through controlled hybridization between selected genotypes from China and Vietnam, genetic gain was obtained in terms of artemisinin content and population uniformity. Through the increase of biomass and artemisinin content (estimated by analytical monitoring), it was possible to increase the artemisinin production of 5 Kg/ha for the base population to approximately 25 Kg/ha for the genetically bred population. In the cultivation carried out in Brazil, 3 of 7 hybrid lines, 2/39 x 1V, Ch x Viet.55 and 1V x 2/43 produced respectively 25.43, 23.05 and 21.27 Kg of artemisinin/ha/cut, with 2 harvests possible per year. The cultivation of these new hybrid lines in Brazil is technically feasible and highly competitive, due to the production obtained.

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