The seeds of plants are rich stores of proteins, carbohydrates, and lipids and are therefore used by heterotrophs as valuable food sources. Humans use seeds as a major food source and have learned, through agricultural practice, how to increase the levels and the quality of their components. They have also learned how to deal with the multiplicity of toxic or antinutritional compounds present in seeds. It is believed that these seeds, most of which are not essential for the establishment of the new plant following germination, contribute to the protection and defense of seeds against pathogens and predators. However, insects, fungi, and bacteria have also learned how to cope with detrimental compounds in order to take advantage of the high nutritional value of seeds.Coleopteran insects of the family Bruchidae, the seed weevils, have been associated with the seeds of leguminous plants through co-evolutionary processes. These processes have permitted the weevils to thrive on seeds full of toxic compounds, in contrast to the majority of the other potential aggressors, which are incapable of dealing with them. The association between bruchids and legume seeds is highly specific with only seeds of a very few species being attacked by any one insect species.Among our food sources, plants of the legume family contribute some of the most important protein-rich seeds. The common bean (Phaseolus vulgaris), native of the New World and the cowpea (Vigna unguiculata), which originated in Africa, are heavily attacked by bruchids, both in the field and in storage. Infestations are commonly so heavy that the seeds are unsuitable for use as food, feed, or planting.Control of bruchid infestation is done by treating stored seeds with methyl bromide, carbon disulfide, and several other chemicals. These are considered environmentally undesirable and are too expensive for subsistence farmers. To increase the insect resistance of cultivated varieties plant breeders are interested in understanding resistance mechanisms that operate in wild varieties or why certain bruchids attack one cultivated species but not another.Both the common bean and cowpea are endowed with compounds called general defensive compounds that protect their seeds against widely different herbivores. Among these are the tannins, cyanogenic glucosides, non-protein amino acids, and proteins such as protease and amylase inhibitors, lectins, chitinases, ␤-1,3-glucanases. These defensive compounds are ineffective against the host-specific bruchids, Callosobruchus maculatus and Zabrotes subfasciatus, which attack cowpea and common bean, respectively. Host-specific defenses are rare and are generally found in populations in the centers of dispersion of the particular plant species. Landraces of cowpea and common bean that produce seeds resistant to their associated bruchids have been discovered respectively in West Africa and Mexico. The biochemical basis of the resistance of cowpea and common bean seeds to C. maculatus and Z. subfasciatus, respectively, is the focus of t...

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The rocky, seasonally-dry and nutrient-impoverished soils of the Brazilian campos rupestre s impose severe growth-limiting conditions on plants. Species of a dominant plant family, Velloziaceae, are highly specialized to low-nutrient conditions and seasonal water availability of this environment, where phosphorus (P) is the key limiting nutrient. Despite plant-microbe associations playing critical roles in stressful ecosystems, the contribution of these interactions in the campos rupestres remains poorly studied. Here we present the first microbiome data of Velloziaceae spp. thriving in contrasting substrates of campos rupestres . We assessed the microbiomes of Vellozia epidendroides , which occupies shallow patches of soil, and Barbacenia macrantha , growing on exposed rocks. The prokaryotic and fungal profiles were assessed by rRNA barcode sequencing of epiphytic and endophytic compartments of roots, stems, leaves and surrounding soil/rocks. We also generated root and substrate (rock/soil)-associated metagenomes of each plant species. We foresee that these data will contribute to decipher how the microbiome contributes to plant functioning in the campos rupestres , and to unravel new strategies for improved crop productivity in stressful environments.