Introduction. A study was conducted in India to assess the efficiency of 32P uptake and the feasibility of intercropping using land-use efficiency parameters in a banana-based intercropping system. Materials and methods. Absorption of 32P applied to plants in five-crop, two-crop and sole-crop systems involving banana Musa AAB (‘Mysore’), ginger (Zingiber officinalis Rosc.), turmeric (Curcuma longa L.), cassava (Manihot esculenta Crantz.) and elephant yam (Amorphophallus campanulatus Blume.) was studied in field trials. The experiment was conducted for two years. During the first year, the main crop was planted during October, the main planting season for banana in India, and the intercrops were planted in early May of the next year. In the second year, both the main crop and intercrops were planted in May. Results. Radiophosphorus applied in the active root zone of one of the component species in the mixed crop system was found to be absorbed not only by the treated plant but also by the neighboring plants. Absorption by banana was prevalent. Differential effects of competition were manifested as observed by the relative uptake of 32P. Lower relative uptake of 32P was observed in the main crop banana when simultaneous planting of intercrops was done. Ginger and turmeric were not affected in relation to planting at different stages of the main crop, whereas cassava and elephant yam showed lesser relative 32P uptake when planted later, confirming that different crops in the mixed crop system react differently. Conclusions. The efficiency of different crops in terms of uptake varied with the system of planting. The higher relative efficiency of 32P uptake in a multiple cropping system points to an improved efficiency of uptake and higher dry weight on a per plant basis. It confirms the efficiency and feasibility of the cropping system. Economic analysis emphasizes the concept and proves the viability of the system.

Introduction. Plant regeneration from in vitro culture of adult citrus tissue may help in early evaluation of important horticultural characteristics of genetic material from breeding programs, which incorporate biotechnological tools. Our research aimed to optimize in vitro culture conditions that could lead to the maximum plant regeneration through organogenesis of ‘Bahia’ sweet orange (Citrus sinensis L. Osbeck) in explants (internodes and foliar disc segments) collected from adult plants grown under greenhouse conditions. Materials and methods. Organogenesis was induced in internodes on DBA3 culture media supplemented with BAP at (0.0, 1.0, 2.0 and 3.0) mg·L–1 combined with NAA (0.5 mg·L–1), and in foliar discs on culture media with BAP at (0.0, 0.5, 1.0, 1.5 and 2.0) mg·L–1 combined or not with NAA (0.5 mg.L–1). Results and discussion. The concentrations of (1.0, 2.0 or 3.0) mg·L–1 of BAP combined with 0.5 mg·L–1 of NAA induced in vitro organogenesis in internodes of ‘Bahia’ sweet orange. The use of foliar discs was not efficient for adventitious organogenesis.

Introduction. L’absence de données statistiques fiables et exhaustives sur les exploitations fruitières constitue un handicap pour élaborer une stratégie pertinente de développement de ces cultures et en évaluer l’impact. Une enquête a été réalisée sur les cultures fruitières dans trois sites (Bokito, Foréké et Yaoundé) en zone humide du Cameroun. Matériel et méthodes. Les arbres fruitiers cultivés ont été caractérisés en analysant le profil du producteur et la place de ces cultures dans les activités pratiquées par les familles des exploitants agricoles. Les espèces présentes, le nombre de pieds, l’origine du matériel végétal, l’âge des arbres et les contraintes de production ont été étudiés dans 193 exploitations familiales agricoles. Résultats et discussion. Les chefs d’exploitation, dont 90 % sont des hommes, ont en moyenne 51 ans et un niveau de formation relativement bas. La diversité des espèces fruitières répertoriées varie suivant les sites. La composition spécifique du verger est aussi variable mais quatre espèces majeures (safoutier, oranger, manguier et avocatier) constituent 78 % des plants recensés. Cette répartition corrobore les préférences exprimées par les producteurs pour ces espèces fruitières. Les jeunes arbres (< 10 ans), qui indiquent une dynamique de replantation, constituent (15, 21 et 38) % des effectifs respectivement à Bokito, Foréké et Yaoundé. Toutefois d’importantes disparités intraspécifiques sont observées et discutées. En termes de contribution à la sécurité alimentaire du ménage, les arbres fruitiers, par rapport aux autres spéculations, occupent le 1er, le 2e et le 4e rang à Bokito, Foréké et Yaoundé, respectivement. Les contraintes de production sont d’ordre parasitaire (maladies et ravageurs), agronomique (variétés, pratiques culturales, etc.) ou socioéconomique (intrants, foncier, etc.). Conclusion. Notre travail a permis d’obtenir d’importantes données sur les arbres fruitiers cultivés en zone humide du Cameroun. Les implications des principaux résultats sont discutées dans la perspective d’améliorer, en qualité, en quantité et dans la durée, ces productions.

Introduction. En Tunisie, pays grand producteur de dattes, les écarts de triage de dattes restent non valorisés malgré une valeur nutritionnelle comparable à celle du fruit de haute valeur marchande. Notre étude a eu pour objectif de tester une voie de valorisation basée sur l'extraction, à partir d’une pâte de datte, d'une boisson de datte clarifiée. Matériel et méthodes. Le schéma technologique du procédé d’extraction de la pulpe a été inspiré d'un procédé traditionnel. Une solution brute obtenue de la dilution de pâte de dattes a été traitée par voie enzymatique (pectinases, cellulases) et par microfiltration tangentielle. La composition chimique, les caractéristiques physicochimiques et les caractéristiques rhéologiques de la boisson clarifiée obtenue ont été déterminées. Résultats et discussion. La solution brute extraite des dattes après broyage, dilution et filtration a une forte teneur en sucre. Le couplage des traitements enzymatique et de microfiltration a conduit à l'élaboration d'une boisson clarifiée, modérément acide, présentant une viscosité et une turbidité relativement faibles et ayant des caractéristiques d'écoulement comparables à celles des boissons et jus de fruits connus. Conclusion. Les écarts de triage de dattes peuvent constituer un sous-produit apte à être transformé, par le biais de procédés usuels, en une boisson agréable et commercialisable.

Introduction. Figs of the variety ‘Roxo de Valinhos’ are currently cooled in a cold room at a temperature between (1 and 3) °C, and it is unknown how long it takes to cool the fruits to that temperature. The work was based on the need to determine the parameters of forced-air precooling of figs packed in a carton box used for exportation and commercialization in São Paulo State, Brazil. Materials and methods. The fruits were harvested at the harvest rami stage (3/4 of maturity) and at size “type 8”, corresponding to eight fruits per box, making up a total of 24 fruits per package. Forty-eight packages were utilized, 24 on each side to form a Californian tunnel. The airflow was 2.8 L·s–1 per kg of product, with an average velocity of the air of 2.0 m·s–1. The initial interior temperature of the fruits was 20 °C and the final temperature was 1 °C. The evolution of the fig interior temperature was registered. Results. The cooling curve was drawn and the exponential analytical model to predict the precooling parameters was made based on the experimental data. The cooling curve of fig showed a typical behavior; the average fruit temperature during precooling presented a rapid fall at the beginning of the cooling, and slowly declined when it was close to the final temperature. Conclusion. The cooling time was 110 min, the cooling coefficient was 0.0344 min–1, the Biot number was 1.3 and the convective heat transference coefficient was 23.8 °C·W–1·m–2.

Introduction. Fruit production is faced with water shortage, especially in areas with a Mediterranean climate characterized by a very long, dry and hot summer. Thus, the growers under such conditions must manage irrigation carefully by finding new strategies, including water stress management. Materials and methods. Effects of water stress (WS) and crop load (CL) on the carbon assimilation rate, fruit growth, crop yield and fruit quality (size and soluble solids content) were evaluated in a 7-year-old ‘Elegant Lady’ peach orchard (Winters, California, USA). The experimental design consisted of a completely randomized block factorial design with 2 × 3 factors: irrigation with two levels (control and WS trees) and crop load with three levels (light, commercial and heavy). Results and discussion. Both CL and WS affected fruit growth during the last stages but not early on. Crop load did not affect trunk water potential (TrWP) which, however, was significantly reduced by WS throughout the day and the season. The stomatal conductance (gs), transpiration rate (E) and CO2 assimilation rate (A) were not affected by CL, but they were reduced by WS. There were poor correlations between TrWP and either gs or A in control trees, indicating relatively poor coordination between leaf functions in peach trees under optimal conditions. Both WS and CL delayed the harvest date through their effect on ripening. Water stress significantly reduced the average crop fresh yield but hardly affected crop dry yield. Both WS and CL affected the distribution of fruit size categories, with the proportion of large fruit decreasing with the increase in crop load and the severity of WS. Conclusion. Water stress reduced fruit fresh weight and fruit fresh yield but not fruit dry weight or dry yield. Crop load reduced fruit fresh and dry weights and yields. Crop load had a negative effect on soluble solids content, while WS had a positive effect. Thus, CL reduced fruit size and soluble solids content, while WS reduced size but improved soluble solids concentration.