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Homegardens contain agroforestry systems that provide diverse resources for familyconsumption in rural communities. The aim of this study was to perform an ethnobotanical inventory of the tree speciesand their uses in the homegardens of two small-scale rural farming communities situated near the Mata Seca State Park,Minas Gerais, Brazil, and to understand the potential role of these agroecosystems in the conservation of native treespecies. Local knowledge about species used was assessed using free lists with 20 small-scale farmers selected using thesnowball sampling technique in each community. All shrub and tree species with a circumference at the soil level  10 cmwere sampled in each homegarden. We confirmed that most plant species listed provided food (48.3%) and shade (35.6%),showing the importance of fruit trees and evergreens in the homegarden flora in this local semi-arid context. Other specieswere also cited as medicinal and ornamental plants. Besides that, some species listed were used for construction, fuel,fodder, fertilizer and other uses. Amongst the 87 tree species, 44 are Brazilian natives, and 23 can be found in the dryforests of the region. These results showed that homegardens can contribute to conservation and enhancement of localbiodiversity functioning as a reservoir of species with different biogeographic origins, including regionally endemic andnative trees. Furthermore we conclude that homegardens are important sources of plant resources for home consumptionand contribute towards a balanced diet and to the welfare of the people living in the communities of north Minas Gerais’semi-arid region.

The soils developed under High Altitude Rocky Complexes in Brazil are generally of very low chemical fertility, with low base saturation and high exchangeable aluminium concentration. This stressful condition imposes evolutionary pressures that lead to ecological success of plant species that are able to tolerate or accumulate high amounts of aluminium. Several analytical methods are currently available for elemental mapping of biological structures, such as micro-X-ray fluorescence (µ-EDX) and histochemical tests. The aim of this study was to combine µ-EDX analysis and histochemical tests to quantify aluminium in plants from High Altitude Rocky Complexes, identifying the main sites for Al-accumulation. Among the studied species, five showed total Al concentration higher than 1000 mg kg -1 . The main Al-hyperaccumulator plants, Lavoisiera pectinata, Lycopodium clavatum and Trembleya parviflora presented positive reactions in the histochemical tests using Chrome Azurol and Aluminon. Strong positive correlations were observed between the total Al concentrations and data obtained by µ-EDX analysis. The µ-EDX analysis is a potential tool to map and quantify Al in hyperaccumulator species, and a valuable technique due to its non-destructive capacity. Histochemical tests can be helpful to indicate the accumulation pattern of samples before they are submitted for further µ-EDX scrutiny.

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Harmonia axyridis is a voracious aphid predator, which has been used in biological control programs in several countries. Due to its fast spreading, H. axyridis is becoming widely distributed across the world. Recently, it was detected in Viçosa, Minas Gerais, southeastern Brazil. This region shows climatic similarity to its native region and it may facilitate the establishment of H. axyridis. The species was found in some home gardens feeding on aphids and psyllids. The presence of the lady beetle in the state of Minas Gerais confirms its high spreading potential in Brazil, reinforcing the necessity for further studies on the possible impacts and control methods of its populations.