Thierry Lescot

Recovery and regeneration of embryogenic cultures from female flowers of False Horn Plantain

Somatic embryogenesis from immature male flowers in Musa is only suitable for genotypes with a male bud. Six friable embryogenic cultures were obtained from 28 cultured buds of female flowers of the AAB False Horn Plantains, ‘Curraré’ and ‘Curraré Enano’. Embryogenic suspensions were established from these embryogenic cultures. Somatic embryogenesis was demonstrated histologicaly. Regeneration of plants was obtained either from somatic embryos directly isolated from embryogenic cultures or from suspensions after plating on a semi-solid medium. This study demonstrates that somatic embryogenesis from immature flowers is suitable for genotypes of Musa with or without male buds.

An Integrated Approach to Control the Black Leaf Streak Disease (BLSD) of Bananas, while Reducing Fungicide Use and Environmental Impact

Bananas are one of the main agricultural productions in the world, and the main fruit crop, with an annual production of about 117 Mt (Lescot, 2011). International trade of bananas represents 14Mt·year–1 with a value of more than 4 billion US

The ‘Plantain-Optim’ dataset: Agronomic traits of 405 plantains every 15 days from planting to harvest

(Loeillet, 2005). The production of bananas for this international trade is grown in a small number of tropical countries mainly located in Latin America (80%), in African and Asian countries, and in the European community (French West Indies, Canary Islands). In all these countries, this industry is economically important and a source of direct and indirect employment. But one of the main problems is that it relies on a very narrow genetic base, the Cavendish subgroup, which is exposing the industry to important pest and disease threats.

Experimental approaches for agro-ecological management of black leaf streak in dry and humid tropical conditions

The ‘Plantain-Optim’ dataset (came from the ‘Plantain-Optim’ experiment conducted from 2009 to 2011 at CARBAP experimental station in Cameroon. The main objective was to describe agronomic potential of nine plantain varieties, including five natural plantains commonly cropped in Cameroon, and four plantain-like hybrids. A completely randomized bloc permitted to compare growth, development and yield of 45 plants per variety split between five replicates. Cropping practices guarantied non-limiting and homogenous conditions. Each plant was measured every 15 days. Data described aerial organ sizes, foliar structure and bunch characteristics of the mother plant. The ‘Plantain-Optim’ dataset includes the complete individual growth of each studied plantain of the ‘Plantain-Optim’ experiment with a 15-day accuracy. It is a useful standard of plantain varietal diversity for comparison with others datasets. Varietal growth and development homogeneity, biomass production or foliar and bunch structures could be further investigated. Moreover, these accurate data on plantain growth could be valuable for plantain 3D modelling.

New approaches to select cultivars of banana with durable resistance to mycosphaerella leaf spot diseases.

Black leaf streak (BLS), caused by the phytopathogenic fungus Pseudocercospora fijiensis, leads to leaf necrosis and often to a substantial reduction in fruit yield. It also causes the fruit to ripen early by reducing the time between harvest and the beginning of natural ripening, called green life (GL). The usual method of control is by spraying fungicides, but this type of management is challenged worldwide due to the high costs, regulation of products, environmental concerns and the development of resistance. Integrated pest control is an alternative management method based on the combination of agronomic practices that can slow down the development of the epidemic, and limit damage to the fruit. Two experiments were conducted in the Dominican Republic and Martinique, to evaluate the performance of an innovative prototype cropping system with no chemical control. This system is based on optimal growth management, to reduce stress and enhance the leaf emission rate, combined with the systematic removal of necrotic parts of the leaves, which strongly limits ascopore sporulation and reduces the effect of BLS on GL. Depending on the conditions and cycles, the reduction in bunch weight with the prototype system versus chemical control ranged from O to 15%. Bananas were harvested at the same physiological age in the prototype and in the control. The bananas harvested from plants with as low as zero leaves left at harvest retained a good aptitude for conservation, with up to 40 days of GL, on average. The limited impact on fruit weight observed suggests that physiological compensation phenomena through remobilization of resources inside the plant (stem, bunch, suckers) occur. Above all, the removal of necrotic leaves prevented a significant negative effect on early fruit ripening when the bananas were harvested at the correct physiological age, and enabled export of the fruit despite the small number of leaves remaining on the plant at harvest. These results offer perspectives for the development and transfer of alternative practices to chemical control.