In situ production of shoots derived from plantain strain-suckers by stimulation with cytokinin substances

Plantain ( Musa x paradisiaca L., AAB genomic group) is a useful supplement to the nutritional balance of populations in developing countries. The objective of this study was to improve the multiplication rate of in situ plantain (Musa x paradisiaca L.) seeds through the supply of substances with cytokinin activity. Suckers of 10 cm height and related to the parent plant, called strain-suckers, were used to produce shoots. The pseudo-trunk of plantain tree was decorticated, then the apical meristem extracted. Four milliliters of each substance (6-Benzylaminopurine (BAP)\ua0; Kin\ue9tine and Coconut water) were introduced in the cavity left by the extracted meristem. For each substances, the effect of the diameter of first-generation strain-suckers (d < 9; 9 < d < 12 cm and d > 12 cm) was tested. This operation was repeated once so as to have the second and third generations. BAP induced the highest number of buds after three generations. The optimal concentration of BAP was 40 mg L-1. Similarly, all concentrations of coconut water stimulated production of seedlings. Among different diameters of strain-suckers, the largest number of buds was induced with strain-suckers larger than 9 cm in diameter. The production of leafy shoots varied greatly, depending on the solutions tested and the size of strain-suckers used. After 3 to 4 months, seedlings obtained were ready to be transferred in the field.L\u2019objectif principal de la pr\ue9sente \ue9tude est d\u2019am\ue9liorer le taux de multiplication des semences in situ de bananier plantain ( Musa x paradisiaca L.) par apport de substances \ue0 activit\ue9 cytokinine. Les rejets ba\uefonnettes de plus de 10 cm de haut et li\ue9s \ue0 la plante m\ue8re ont \ue9t\ue9 r\ue9pertori\ue9s et appel\ue9s souche-rejets. Le pseudo tronc de ces derniers a \ue9t\ue9 d\ue9cortiqu\ue9 puis le m\ue9rist\ue8me apical extrait. Dans la cavit\ue9 laiss\ue9e par l\u2019extraction du m\ue9rist\ue8me, 4 ml des solutions de Benzylaminopurine (BAP)\ua0; de Kin\ue9tine (Kin) ou de l\u2019eau de coco y ont \ue9t\ue9 introduites. Cette op\ue9ration a \ue9t\ue9 r\ue9p\ue9t\ue9e de sorte \ue0 disposer des rejets de deuxi\ue8me et troisi\ue8me g\ue9n\ue9ration. La substance induisant le plus grand nombre de bourgeons a ensuite \ue9t\ue9 utilis\ue9e pour tester diff\ue9rents diam\ue8tres de rejets (d < 9 cm\ua0; 9 < d < 12 cm et d > 12 cm). La BAP a permis d\u2019induire le plus grand nombre de bourgeons apr\ue8s trois g\ue9n\ue9rations. La concentration optimale de BAP a \ue9t\ue9 de 40 mg L-1. De m\ueame, le lait de coco a permis de stimuler la production de plantules. Parmi les diff\ue9rents diam\ue8tres de rejets, le nombre moyen le plus important de bourgeons a \ue9t\ue9 induit avec les rejets de diam\ue8tre sup\ue9rieur \ue0 9 cm. La production de pousses feuill\ue9es a vari\ue9 fortement selon les solutions test\ue9es et la taille des rejets utilis\ue9s. Au bout de 3 \ue0 4 mois les plantules obtenues sont pr\ueates \ue0 \ueatre transf\ue9r\ue9es au champ