Introduction. La diffusion de nouvelles variétés issues de programmes d’amélioration génétique (hybrides ou introductions) rencontre parfois des difficultés. Pour limiter ce problème, une démarche méthodologique visant à faciliter l’adoption de ces variétés par les planteurs a été mise au point au Cameroun sur un hybride de type plantain. Matériel et méthodes. La démarche entreprise a cherché successivement à hiérarchiser, par enquête, les critères de préférences variétales privilégiés par les producteurs ; à tester, par des essais en conditions réelles, en quoi une nouvelle variété répondait à ces critères ; à évaluer les performances agronomiques de l’hybride et d’une variété témoin en fonction de la diversité des milieux. Résultats. Les résultats ont souligné l’intérêt de l’approche présentée pour comprendre les déterminants d’adoption d’une nouvelle variété par les planteurs. Ils fournissent des informations utiles pour le pilotage de futurs programmes d’amélioration génétique. Ils révèlent des difficultés méthodologiques dans la réalisation d’essais interdisciplinaires en conditions réelles, qui devront être pris en compte pour l’amélioration des protocoles futurs. Conclusion. Les conditions d’adoption d’une nouvelle variété varient selon les localisations, compte tenu des variables pédoclimatiques, et selon les planteurs, compte tenu des contraintes socio-économiques. L’offre variétale doit donc être diversifiée pour répondre à la diversité des demandes. La démarche effectuée gagnerait à être complétée par des enquêtes auprès d’autres opérateurs de la filière. Notre expérimentation doit être considérée comme une première contribution à une démarche plus large.

Introduction. Rhizobacterial inoculation in low fertilizer-N conditions, viz., 33% fertilizer-N of the total N requirement, could produce similar plant growth to the 100% N-fertilization of banana plantlets grown under hydroponic conditions. Thus, we tested PGPR inoculation in combination with fertilizer-N application to study the role played by strains of rhizobacteria in nutrient accumulation, nitrogen fixation and, consequently, improvement in yield and fruit quality of bananas. Materials and methods. Two PGPR strains were used in the experiments, namely, Sp7 (Azospirillum brasilense) and UPMB10 (Bacillus sphaericus). The design of the experiment was completely randomized with three replications. Eight treatments were applied: control without fertilizer-N application (N0%) and without PGPR; N0% + Sp7; N0% + UPMB10; N33% without PGPR; N33% + Sp7; N33% + UPMB10; N100% without PGPR and N100% + UPMB10. One tissue-cultured banana (cv. ‘Berangan’) plantlet was planted in a plastic pot (4 L) for 45 days and thereafter transferred to a larger polyethylene tank (1000 L) until maturity. A 100-mL broth culture of Sp7 or UPMB10 was added to the respective tanks after the transplanting process and repeat inoculations were performed monthly. The fruits were harvested at the maturity stage after 80–90 days of flowering. After ripening, yield and fruit quality parameters were assessed. Results. Inoculation with 33% fertilizer-N increased the total nutrient accumulation (N, P, K, Ca and Mg). PGPR inoculation along with 33% fertilizer-N significantly increased the bunch yield and fruit physical attributes, namely, finger weight, length and diameter, and [pulp / peel] ratio, besides inducing early flowering by 3 weeks. Conclusion. The results suggested that PGPR strains Sp7 and UPMB10 could be used as bioenhancer and biofertilizer for early, high-yielding and improved banana fruit production in 33% fertilizer-N conditions.

Introduction. The citrus industry is one of the main activities of Brazilian agriculture. Several pests and diseases have threatened citrus culture in recent years. Genetic mapping is one of the most efficient strategies for conducting advanced genetic studies by facilitating plant selection guided by markers. The objective of this study was to construct an integrated genetic map between Citrus sinensis (L.) Osbeck cv. ‘Pêra’ and C. reticulata Blanco cv. ‘Cravo’ using two different types of segregation of markers. Materials and methods. The linkage analyses were conducted with segregation data obtained from 256 RAPD markers in a population of 94 hybrids. Analyses were performed through the software JoinMap, LOD ≥ 6.0, θ ≤ 0.25, and the Kosambi function. Results and discussion. The linked map between the two cultivars had 217 markers defined by 15 linkage groups, covering 527 cM. This map had five linkage groups with common markers of ‘Pêra’ and ‘Cravo’. The inclusion of new markers would increase the number of linkage groups with markers from both parents, thus making their number equal to the haploid chromosome number. The alterations in the order and in the distances among the markers, due to the presence or absence of bridging markers in the linkage map, are discussed.

Introduction. Root restriction occurs when seedlings are grown in increasingly small containers and it reduces plant growth in different ways. Therefore, the objectives of our study were to investigate the effects of varying container sizes and irrigation frequency on growth parameters of ‘Rough lemon’ (C. limon) plants Maseno, Kenya. Materials and methods. The treatments tested the effect of three container volumes (1.7 L, 2.7 L and 4.5 L) and three irrigation frequencies [every day (W1), every two days (W2) and every 3 days (W3)]. The design of the experiment was completely randomized with three replications. Growth parameters studied were plant height, canopy height, shoot and root weight, number of leaves and shoot to root ratio. Results and discussion. Increasing container volumes generally increased the height of plants, height of canopy, weight of whole plants and weight of roots, but it did not affect number of leaves, stem diameter or shoot to root ratio. Irrigation frequency increased number of leaves, height of plants, height of canopy, stem diameter and weight of shoots and roots, but this factor had no effect on weight of whole plants. These findings are explained by reduced root restriction in the largest container volumes. Conclusion. Increasing container volumes from 1.7 L to 4.5 L and irrigation frequency from every 3 days to every day increases plant growth as expressed in the various plant growth parameters.

Introduction. Mature-green Golden apples (Spondias cytherea Sonnerat) are used in the French West Indies for the preparation of a nectar. With the aim of improving the fruit processing conditions for a better quality of this beverage, morphological and compositional characteristics of the mature-green fruits were determined. Materials and methods. Mature-green fruits were harvested in Martinique (French West Indies) and characterised: diameter, length, mass, and colour were determined; pH, titratable acidity, soluble solids, sugars, proteins, starch, fibre, vitamin C, phenols and green pigments were measured. Results and discussion. Average fruit length, diameter and weight were 71 mm, 54 mm and 116.4 g, respectively. With a low pH (2.6) and a high titratable acidity (1.3 g citric acid Eq·100 g–1 fresh material), mature-green Golden apple is an acidic fruit comparable to the lemon. The fruit is rich in vitamin C (52.0 mg·100 g–1), phenols (349.5 mg gallic acid Eq·100 g–1) and starch (7.1 g·100 g–1). The pale green colour of the pulp is due to pheophytins a and b. Conclusion. Our study provided a detailed analysis of mature-green Golden apples, which will be taken into account for the improvement of nectar processing conditions.

Introduction. Although some of the non-formal food items consumed in Southeastern Nigeria are exotic, the indigenous products are becoming increasingly popular. There is also a growing interest among scientists in various disciplines to conduct research on nutritional, medicinal, industrial and other uses of the less studied and largely indigenous plants. Unlike the exotic fruits and seeds literature on the purely indigenous species is scanty. This paper is aimed at the documentation of some of the readily identified species producing fruits and seeds, which are considered to be endangered. Materials and methods. Selected plants producing edible fruits and seeds and considered to be endangered in Southeastern Nigeria were compiled in a list. Mature forms of the fruits and seeds were covered by means of color photographs and further categorized according to their families, growth habits, state of domestication, local names and methods of utilization. Results and discussion. Thirty plant species belonging to 19 families were recorded. The list includes 19 trees, 3 shrubs, 4 climbers and 2 rhizomatous monocots. About 27% of the species listed enjoy some degree of cultivation, while about 70% may still be found protected or wild. Up to 16% are still harvested only from the wild plants. The factors predisposing most of the species to extinction would be: loss of habitat due to deforestation and other forms of population pressure on the ecosystem; lack of interest in tree planting due to rather long gestation periods of existing genetic stock; increasing pressure and demand from few surviving stands; unsustainable harvesting methods. Conclusion. Ex situ conservation strategies, genetic and other tree improvement studies, encouragement of home garden and village forest settlement practices, and the introduction of incentives for tree planting are recommended strategies for conservation and sustainable production of the highly prized indigenous edible fruit and seeds in the area.