This work aimed to characterize physically and physiologically buffelgrass seeds collected in different municipalities located in the semiarid region of Bahia and at different positions in the panicle. At each site, two hundred mature, whole panicles were collected when seeds were naturally falling. A 5 × 3 factorial in a completely randomized design was used. Factors were five municipalities where seeds were collected and three positions within the panicle (bottom, middle and top portions), with four replicates of 50 seeds for each treatment. Moisture content, dry seed weight, electrical conductivity, germination percentage, germination speed index and emergence speed index were assessed. Data were tested by analysis of variance and Tukey test at 5% of significance level. Soil and climate conditions of each region affect the physiological quality of buffelgrass seeds. Seeds located in bottom and middle portions of the panicle are more vigorous than seeds located in the top portion. The municipality of Poções has better conditions for yielding buffelgrass seeds of better quality than the remaining municipalities.

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Understanding the effects of different production systems on arbuscular mycorrhizal fungi (AMF) can help to interpret interactions between their components and to defi ne management strategies. As a result, our study was conducted on soils under three coffee production systems (one homogeneous and two heterogeneous) and in a native forest located in the Bahia state, Brazil. This study aimed to answer the following questions: 1) Does the organization and management of the coffee production system affect the occurrence and diversity of AMF?; and 2) Is the seasonality effect similar between systems? To do so, soil samples (0-10 cm depth) were collected at two times of the year (rainy and dry). Number of spores (NS) and average richness did not show differences between the systems, only between seasons. There was a reduction in NS in the dry season (1.4 and 2.7 spores g -1 soil) in relation to the rainy season (3.8 to 12.5 spores g -1 soil). The infl uence of coffee production systems was observed in the presence and absence of some AMF species. The AMF community was shown to be related to the plant species composition of the system, which was refl ected in the dissimilarity of heterogeneous systems in relation to the coffee monoculture system.