Banana and plantain are consumed by over five hundred million people around the world. Despite their market value and importance in ensuring global food security, several pests and diseases threaten their yield. Banana bunchy top disease (BBTD) is one of the world’s most destructive diseases of banana and plantain causing up to 100 % yield loss in severe cases. Transboundary exchange of infected planting materials and banana aphid (Pentalonia nigronervosa) are the two transmission modes of the disease. Banana aphid harbouring banana bunchy top virus (BBTV), is the sole vector and an efficient method of transmission of the virus from infected to healthy plants. Controlling the spread of BBTD has been very challenging since there is no known banana germplasm containing an endogenous gene that could confer absolute resistance to BBTV. Therefore, the preeminent way of controlling the virus starts with controlling the vector. Biotechnological strategies via RNA interference (RNAi) could be used to target banana aphid as well as BBTV to reduce virus-associated banana and plantain yield losses. The aim of this study was to generate transgenic plantains using RNAi as a strategy to control banana aphids. Plant tissue culture techniques such as somatic embryogenesis and genetic transformation offer a valuable tool for genetic improvement. Identification and quantification of phytochemicals found in banana and plantain are essential in optimizing in vitro activities for crop improvement. Total antioxidant capacity, flavonoids, tannins and phenol were determined with varying concentrations in the root, pseudostem, leaf explant and in in vitro samples of plantain and banana cultivars. Embryogenic cell suspension (ECS) was developed for three farmer-preferred plantain cultivars, Agbagba, Obino l’Ewai and Orishele. Both Murashige and Skoog (MS) and Gamborg (B5)-based culture media supported the development of friable embryogenic callus (FECs) in plantain cultivars while MS culture media supported the proliferation of fine cell suspension in liquid culture media. Up to 22 ± 24 %, 13 ± 28 % and 9 ± 16 % FECs were obtained for Agbagba, Obino l’Ewai and Orishele cultivars, respectively. To design a reliable synthetic diet for in vitro aphid feeding, the type of available sugars in banana and plantain were first analysed and shown to include sucrose, fructose and glucose at varied levels. An optimal synthetic diet containing 7.5 % sucrose supported the survival of banana aphid in vitro. The efficacy of acetylcholinesterase as the targeted gene in banana aphid was determined through an in vitro feeding assay of banana aphid using dsRNA and siRNA both of which conferred lethal effects on banana aphid. Banana and plantain cell suspension was transformed by Agrobacterium-mediated transformation with pNXT-35S-ACE-hp gene construct. The presence and integration of the transgene in elite plants was confirmed by PCR and Southern blot assays. Transgenic events generated were screened for resistance to banana aphid and up to 46.7 %, 75.6 %, and 67.8 % reduction in aphid population was observed in Gonja Manjaya, Orishele and Cavendish Williams respectively compared to those grown on the wild-type plants under glasshouse condition. These results suggest the effectiveness of RNAi targeting an essential aphid gene, could be a useful way of managing the infestation of banana aphid and reducing the spread of BBTD.

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