Introduction. Les réactions d’oxydation constatées régulièrement dans les aliments peuvent causer des dommages importants, entraînant parfois des cancers et maladies chroniques. Les extraits d’huiles essentielles étant connus pour posséder d’importantes propriétés thérapeutiques, notre étude a cherché à comparer les activités antiradicalaires et anti-inflammatoires des essences de C. reticulata var. Madagascar et C. sinensis var. Casagrande. Matériel et méthodes. Les huiles essentielles des feuilles d’agrumes ont été extraites par hydrodistillation et leur composition chimique a été analysée par chromatographie en phase gazeuse et par chromatographie en phase gazeuse couplée à la spectrométrie de masse. La détermination des propriétés antiradicalaires a été faite par la méthode du piégeage des radicaux libres à l’aide du diphenyl picryl hydrazyl (DPPH). En revanche, la méthode enzymatique par la lipoxygénase a permis d’évaluer l’activité anti-inflammatoire des extraits d’huiles essentielles obtenues par hydrodistillation. Résultats. Les propriétés antiradicalaires de nos échantillons ont été évaluées avec une SC50 égale à (4,10 ± 0,05) g·L–1 et (7,40 ± 0,55) g·L–1, respectivement, pour C. reticulata var. Madagascar et C. sinensis var. Casagrande, alors que le composé antiradicalaire de référence (butylhydroxytoluène ou BHT) donnait une SC50 de (7,02 ± 0,5) mg·L–1. Par ailleurs, les deux échantillons ont montré une activité anti-inflammatoire exploitable (IC50 de 53,5 mg·L–1 et 20,3 mg·L–1, respectivement) même si le NDGA (acide nordihydroguaiarétique) a eu une IC50 de 0,7 mg·L–1. Conclusion. C. reticulata var. Madagascar se révèle avoir une activité antiradicalaire plus importante que C. sinensis var. Casagrande, alors que cette dernière espèce a présenté l’activité anti-inflammatoire la plus marquée. Ces huiles essentielles pourraient être utilisées comme additifs alimentaires.

Introduction. Fruit flies contribute significantly to yield losses experienced by citrus farmers in Nigeria. The majority of farmers have meager resources and limited knowledge of appropriate citrus pest management strategies. The best alternative for them is the application of control methods that are environmentally friendly and affordable. Our work was therefore designed to develop baits from a cheap source for monitoring fruit fly populations and controlling them while minimizing environmental hazards. Materials and methods. Protein bait prepared locally from brewery yeast waste by the process of heat autolysis was compared with the imported protein hydrolysate bait in McPhail traps. These traps were hung on the trees of four sweet orange varieties during the major citrus fruiting seasons of 2003 and 2004. Results. Species of Ceratitis dominated in the fruit fly samples collected. Both the imported and locally made baits caught significantly higher numbers of fruit flies than the non-baited control. There was no significant difference between the populations of fruit flies caught by the two baits during the studies. The decreasing order of varieties according to trapped fruit fly numbers for both the imported and locally made baits were: Washington navel > Parson Brown > Valencia late > Agege-1. The fruit fly numbers observed on Washington navel were significantly higher than those of Agege-1 and Valencia late. Discussion. Our results show the effectiveness of the locally made protein bait in fruit fly monitoring and management. Varietal differences also played a part in determining the extent of fruit fly attacks on sweet oranges.

Introduction. Canarium schweinfurthii, a tree species in the rainforest of Nigeria whose fruits are intensively gathered and eaten, is seriously endangered because of poor seed germinability and usage. Our study examined the pattern of seed distribution of C. schweinfurthii in the soil from the stem base of the parent plant and through the soil profile, and it assessed the seed level of germinability. Materials and methods. Four stands of C. schweinfurthii were selected from a study area in Southeastern Nigeria. Soils were collected from six distances from each trunk base (1 m, 5 m, 10 m, 15 m, 20 m and 25 m) and at four soil depths (0–5 cm, 5–10 cm, 10–20 cm and 20–30 cm); then seeds of C. schweinfurthii were isolated from the cores. Moreover, the percentage of viability and germinability of the seeds collected from each distance and depth were determined. Results. The maximum number of seeds occurred at 1 m from the trunk base (82.3 seeds·30 cm–2), which was 55% of the total collected seeds, and no seed occurred beyond 20 m from the trunk base. The mean number of C. schweinfurthii seeds occurring at 0–5 cm soil depth was 51.3 seeds·30 cm–2, which was the highest from any profile. No seeds occurred below 20 cm. Sixty-seven percent of the total 148 seeds collected were considered viable, with about 80% of them occurring at the 0–5 cm soil depth. Even with the pre-sowing treatment (cutting the hard endocarp), only 30.8% of viable seeds collected from 0–5 cm soil depth were able to germinate, while 10% of those collected from 5–10 cm depth germinated. Conclusion. The localization of over 80% of C. schweinfurthii seeds within a 5-m radius from the stem base and 65% within 0–5 cm soil depth encourages easy fruit gathering by local sellers and leads to depletion of the seed bank. Seedling multiplication, protection of stands and domestication need to be initiated to lift C. schweinfurthii out of endangered status, considering the demand for the fruit and poor seed germination due to the hard endocarp.

The plant. The aguaje (Mauritia flexuosa L.f.) is an Amazonian palm in the process of domestication to be cultivated as a dwarf form. In Peruvian Amazonia, it has a major impact on the economic, social and ecological systems. Fruit are sold and take part in the economy of Peruvian Amazonia. The insects. In this survey, the authors present 18 species of insect pests observed in eight different localities in the surroundings of the city of Iquitos (Loreto, Peru) between 2000 and 2003. Among those species, four develop in the pulp of the fruit, two are borers of the rachillae, one is a borer of the trunk and the petioles of the young leaves, two species bore the rachillae and floral buds, one develops in buds of female flowers and another damages the base of the roots; eight of those species are considered as the most important pests: Eupalamides cyparissias Fab., Antiteuches kerzhneri Rider, Stenoma sp., Clinodiplosis sp., an unidentified species of Cecidomyiidae, Tyrannion sp. and two unidentified species of Curculionidae. Discussion. The cultivation of the dwarf aguaje is a good alternative to the cutting of the native palms to harvest the fruit, but the cultivated palms are damaged by insects. The planters must learn to know those pests to control them. The biology and the ecology of the new pests are currently being studied.

Introduction. The production of high quality fruit juice involves several cultural inputs. Among other factors, fruit quality attributes are influenced by the cultivar, the climate, the harvesting time and soil fertility. Particularly, the soil fertility has a significant effect on the nutritional characteristics of the juice. Good practice as regards fertilization consists of applying rates adapted to plant optimum growth, yield and fruit quality. Materials and methods. Effects of four poultry manure rates [(0, 5, 10 and 15) t·ha–1] on the juice quality of passion fruits (Passiflora edulis var. flavicarpa) were evaluated for two cropping years (2005 and 2006). The seedlings of passion fruit vine were field-established in a randomized complete block design, and the manure treatments were replicated four times. Juice quality assessment was performed on fruits picked in December 2005, coinciding with the dry season and low soil moisture recharge, and August 2006, during the wet season and high soil moisture recharge. Results. The results obtained indicated a significant poultry manure effect on all the juice quality parameters studied; the quality of the juice increased gradually as the manure rate increased. Similarly, the season of fruit-picking had a significant effect on the juice quality. As expected, vines that received no manure produced fruits with the poorest juice quality, suggesting unfavorable nutritive conditions within the vines. The concentrations of anti-nutrient factors (tannin, hydrogen cyanide, phytate and calcium oxalate) were low in ripe yellow passion fruits, and insignificant regarding health hazards for consumers of yellow passion fruit. Conclusion. The results obtained showed that the manure rate and the harvest period affected the quality of passion fruit juice. Application of 15 t·ha–1 poultry manure generally gave the best juice quality; similarly, fruits harvested in the first cropping season had better juice quality.

Introduction. The centrifugal-flotation technique allows all nematode species and life stages to be separated from root debris and residual soil particles to facilitate their observation. The principle of the method applied, key advantages, starting plant material and time required are presented. Materials and methods. Necessary laboratory materials, and details of the 19 steps required for extracting nematodes from plant tissue for counting are described. Possible troubleshooting is explained.

Introduction. This protocol aims at measuring fruit ethylene production during ripening. It can be used to compare ethylene production between different banana varieties or to compare ethylene production between fruit produced in different pedo-climatic conditions. The principle, key advantages, starting plant material, time required and expected results are presented. Materials and methods. This part describes the required laboratory materials and the three steps necessary for calculating the amount of ethylene produced during banana postharvest ripening. Possible troubleshooting is considered.

Introduction. This protocol aims at preparing total RNA for gene expression analysis by Northern blots, RT-PCR and real-time quantitative PCR; cDNA isolation by RT-PCR; and cDNA library construction. The principle, key advantages, starting plant material, time required for obtaining total RNA and expected results are presented. Materials and methods. This part describes the required materials and the 27 steps necessary for preparing RNA from peel and pulp fruit tissue: preparation of plant tissue powder, preparation of the complete RNA extraction buffer and isolation of RNA from ground banana fruit tissue. Results. Extraction of total RNA by the method described makes it possible to achieve electrophoresis under denatured conditions and in vitro reverse transcription. An example for Northern blot analysis is illustrated.

Introduction. This protocol aims at detecting and evaluating sensitivity shifts in Colletotrichum musae populations towards fungicides that are currently used for the control of postharvest diseases of bananas. The principle, key advantages, starting plant material, time required and expected results are presented. Materials and methods. The necessary laboratory materials and details of the twelve steps of the protocol for banana sampling and anthracnose lesion development, the agar plate preparation, single-spore isolation, germination test, and data analysis are described. Possible troubleshooting is mentioned. We obtain (a) for antimitotic products, the percentage of resistant strains in the population analysed; (b) for Sterol Biosynthesis Inhibitor (SBI) fungicides, the variation and distribution of the isolates' sensitivity within the population analysed according to their level of radial growth reduction by the fungicide.