Passiflora edulis Sims, “maracuyá” (passion fruit), is a globally consumed tropical fruit that can be eaten raw (fresh) or processed. The aim of the current work is to establish its micrographic diagnostic values, permitting botanical quality control to be carried out of commercial products derived from the fruits, thereby incorporating added value. Micrographic techniques were applied such as mild dissociation (5% NaOH at 100° for 5 min), scraping and a histochemical reaction with dissolution of Lugol for starch. The micrographic features found were unicellular, conical, rigid hairs wide at the base (70.75 µm), groups of irregular-shaped sclereids (25.08 µm), clusters of calcium oxalate (17.17 µm), thickened parenchymal cells and starch grains (8.37 µm), the final item comprising a complementary reference used only when no thermal actions were involved in product elaboration. Columnar sclereids are also present in the seeds. Most of the products presented botanical quality, with the exception of one in which characters of diagnostic value of the fruit of the pear were identified. These are indispensable characters for verifying the true nature of foods made with "passion fruit".

Our objective was to evaluate the suppression of root infection by the nematode Meloidogyne incognita in tomato roots previously colonized by arbuscular mycorrhizal fungi (HMA) native of Buenos Aires Province. Tomato plants were inoculated at sowing with a consortiumcontaining HMA= HMA0, HMA50 and HMA100 corresponding to 0, 50% and 100% of substrate with HMA (8 replications). At 40 days, inoculated plants showed HMA colonization higher than 60%. Plants were transplanted and each treatment was inoculated or not with M. incognita (4 replications of each nematode inoculation treatment). At harvest (115 days of growth) plants inoculated with HMA without nematodes showed mycorrhizal colonization higher than 90%. Although plants inoculated with nematodes showed decreases of mycorrhizal colonization, the obtained levels were higher than colonization prior to transplant. Inoculation with HMA decreased both soil abundance of nematode larvae (j2) and number of root galls. Although aerial growth of tomato was not affected by inoculation (HMA or nematodes), HMA0 plants (independently of nematode inoculation) showed higher root growth, that can be considered a strategy of the plant in order to compensate the lower volume of root exploration in the absence of HMA hyphae. Our results showed reduction of nematode density (j2, galls and egg masses) after inoculation of tomato with HMA. It may be concluded that the adequate establishment of mycorrhizal colonization prior to infection with nematodes exerts an apparent control of the infection of the M. incognita nematode in tomato roots. It could be a strategic tool for the biological control of pathogens of horticultural crops.

The search for good quality hardwood vegetables has grown, and consumers are becoming increasingly demanding as to the appearance, color and size of these products. Chemical quality is one of the main programs used in food control. The objective of this paper was to determine the macronutrient contents in leafy vegetables marketed in open fairs in the city of São Luís. The experiment was carried out in the laboratory of mineral nutrition of plants of the engineering nucleus of the State University of Maranhão. From a universe of 14 hardwood vegetables, six of the highest consumption in five free fairs through the application of questionnaires, were selected. Sulfuric digestion/ hydrogen peroxide and P and K determined the N contents by nitroperchloric digestion. The six leafy vegetables selected were: Lactuca sativa, Allium schoenoprasum, Coriandrum sativum, Brassica oleracea var. capitata, Talinum triangulare and Hibiscus sabdariffa. It was verified that the regional vegetables are the most consumed by the population, with emphasis on the non conventional vegetables Hibiscus sabdariffa and Talinum triangulare. The results obtained in the chemical analyses showed potassium and phosphorus deficiency for the samples of Lactuca sativa and Brassica oleraceacapitata in the five fairs studied, indicating inadequate mineral fertilization (excess or deficiency) of these vegetables. While for other unconventional vegetables, more studies are necessary because literature is deficient in information about them.