RESUMO
BACKGROUND: In Kenya, rice (Oryza sativa L.) is mainly produced under irrigation by small-scale farmers. Mwea irrigation scheme (MIS) in Kirinyaga County accounts for 80-88% of rice production. Here, rice is the main source of livelihood and a source of revenue generation for the county. However, a recently established invasive freshwater snail, Pomacea canaliculata (Lamarck) (family: Ampullariidae), a species of apple snail, presents a serious threat to rice production. RESULTS: Household surveys, focus group discussions and key informant interviews highlight apple snail as a serious problem in MIS. Households that observed at least a moderate level of infestation (>20% of cultivated area) experienced significant reductions in rice yield (~14%) and net rice income (~60%). Farmers reported increased use of chemical pesticides for management of apple snail. In addition, the cost of hired labor for physical removal of egg masses and snails is resulting in substantial negative effects on net income. Farmer age, area of land owned, responsibility for decision-making, receipt of extension advice, training, and membership of a farmer organization, were all statistically significant variables to explain farmers awareness of the need for area-wide apple snail management. CONCLUSION: Strategies to limit the spread of apple snail are urgently needed. A Multi-Institutional Technical Team (MITT) has been established to spearhead management efforts and consolidate advice to farmers on how to manage apple snail. However, without action to mitigate spread, the consequences could be disastrous for rice production and food security in Kenya, and for other rice growing regions across Africa. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
RESUMO
During surveys for the potential biocontrol agents Merochlorops species complex (Diptera: Chloropidae), to control the invasive weed Hedychium gardnerianum Sheppard ex Ker Gawl. (Zingiberaceae), two new species of Rhogadopsis Brèthes (Braconidae: Opiinae) viz., R. gratia Gupta van Achterberg, sp. n. and R. macrusa Gupta van Achterberg, sp. n. were reared as solitary larval-pupal parasitoids of Merochlorops in the stems of H. gardnerianum. Interestingly, both wasp species have very different ovipositor lengths, in addition to other characters for species delimitation. Perhaps parasitism by the respective wasp species depends on the thickness of the stem harbouring the chloropid larvae. In the present study, both these new species of wasps are described and illustrated, together with notes on their biology. For the first time the genus Rhogadopsis has been found associated with Chloropidae; earlier records concern Agromyzidae.
