Components of resistance to banana weevil (Cosmopolites sordidus) in Musa germplasm in Uganda

Abstract

A field screening trial undertaken in Uganda showed that a number of Musa L. (Musaceae) cultivars and hybrids displayed high levels of resistance to banana weevil, Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae), while most highland banana cultivars tended to be susceptible to weevil attack. In this study, research was undertaken to determine modalities of resistance to banana weevil. Laboratory studies suggested that all cultivars were attractive to the weevil and that females freely oviposited on all cultivars. While some differences were found between cultivars in attractivity and egg numbers, these were not related to subsequent damage. Therefore, antixenosis does not appear to play an important role in host‐plant resistance to banana weevil. Larval survivorship rates in living corms were, for the most part, low on resistant cultivars, suggesting that antibiosis mechanisms offer the primary avenues of resistance. In the laboratory, development was slower on some resistant cultivars although survivorship rates on excised corm material were not as well related to levels of resistance as that on living material. Sap appeared to play a minor role in reducing egg eclosion rates on some resistant cultivars. Methanol extracts from Kayinja, a resistant cultivar, inhibited larval development on corms of susceptible cultivars in the laboratory.

Volatile Organic Compounds from Entomopathogenic and Nematophagous Fungi, Repel Banana Black Weevil (Cosmopolites sordidus)

“…It causes more crop destruction than any other arthropod pest in all banana producing countries [5]. BW-resistant banana plants do not cover main commercial cultivars, making this pest a severe problem [74][75][76].…”

Banana defence responses to Cosmopolites sordidus feeding and methyl jasmonate application

“…In both cultivars, banana plants suffered considerable rhizome injury from feeding C. sordidus larvae at varying degrees. Such damage variations are a dependant of cultivar resistance Km5 or susceptibility Mbwazirume (Kiggundu et al, 2007; Night et al, 2011). This emphasises the need to evaluate alternatives like MJ whose application on crops like Picea abies improved its resistance against Ceratocystis polonica (Franceschi et al, 2002).…”

“…Tissue culture banana (AAA) plantlets of the sweet dessert‐type cultivar “Yangambi” and the starchy cooking‐type cultivar “Mbwazirume,” an East African Highland banana, were used for the experiments at the Crops Research Institute (CRI) in Kumasi, Ghana, in 2015. Yangambi, also known as “Km5,” is tolerant to C. sordidus , while Mbwazirume shows susceptibility (Kiggundu, Gold, Labuschagne, Vuylsteke, & Louw, 2003a, 2003b; Kiggundu, Gold, Labuschagne, Vuylsteke, & Louw, 2007; Night et al, 2011). Plantlets were grown in 10 L plastic pots, containing sterilised peat, and fertilised with a 5 g mixture of 23% nitrogen (N), 10% phosphorus pentoxide (P 2 O 5 ) and 10% water‐soluble potash (K 2 O) each week for 3 months prior to treatment applications.…”

“…Cosmopolites sordidus adults were trapped from infested plantations near the CRI, using the method as described by Ogenga‐Latigo and Bakyalire (1993). They were maintained during ovulation and hatching of larvae on weekly supplied freshly cut plantain rhizomes inside 10 L plastic buckets that were closed with perforated lids for aeration (Kiggundu et al, 2003a). Each treatment plant was inoculated with three, two‐day‐old larvae by introducing them into knife‐carved notches just below the collar.…”

Respuesta de monocultivos y mezclas de cultivares de Musáceas a la infestación de Cosmopolites sordidus (Germar) (Coleóptera: Curculionidae)

“…La variación de los niveles de daño por C. sordidus observados dentro de los genotipos de Musas se ha atribuido a la dureza del cormo ya las características químicas antibiosis, Abera et al, 1999 yKiggundu et al 2007. Aunque en este estudio se ha considerado que el mezclar cultivares susceptible y resistente a la plaga se observó claramente que disminuye…”