The suckering behaviour of plantains (Musa, AAB) can be viewed as part of an evolved reproductive strategy

Plantains (Musa, AAB), a major food source in the tropics, produce vegetative off-shoots (suckers) arising from lateral buds. In warm environments too few suckers are produced to allow successful perennial cultivation of the crop. We hypothesized that increased growth of the parent (main stem) (A) would promote suckering but environment would limit the number of suckers (S). We introduced an alternative way of viewing the issues involved by identifying the role of temperature (T) and development of the ‘mat’ or genet for successful ratoon crop cycles. The problem was placed within an agricultural/ecological context, highlighting intra-mat interactions and the vegetative response of plantains to T. Using published data from an experiment with 4 sites, 5 cultivars and 4 crop cycles in North Kivu, DRC, the equation S=A.c.exp[-b(T)] described S at flowering as a function of basal pseudostem area at flowering (A) and site temperature (T). Coefficient ‘b’ was negative and is the response of suckering efficiency (S/A) to site temperature, range 16 °C to 24 °C. The coefficient ‘c’ is suckering capacity. Both coefficients differed among cultivars. A parent mat component contributed 1.6 suckers to the first ratoon crop with its contribution varying in subsequent cycles. Across sites, increasing site temperature increased A by 55% but reduced S by 75%. However, within sites increased A promoted suckering of the parent. This conundrum between growth and suckering may be viewed as part of an evolved reproductive strategy whereby temperature affected plant development and morphology with consequent changes in resource allocation that promoted suckering at cool temperatures. Relationships between S, T and A are relevant for managing suckering and the adaptation of plantains to different environments. Practical outcomes could involve modifying soil temperature and growth, and selecting or breeding cultivars with improved suckering under warm temperatures.