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The sugarcane agro-industry is a major producer of organic waste, which could be used as substrates for production of pre-sprouted sugarcane seedlings aiming at reducing production costs and the sustainability of the sugar and alcohol industry. This study aimed to identify the best position of origin of the bud chip (little portion of stem with one bud) for the production of pre-sprouted seedlings (PSS) of sugarcane and the effects of commercial and alternative substrates containing by-products of the sugarcane industry on the production of sugarcane PSS. For this, a 4x2 factorial experiment was performed with four substrates: two commercial (TRIMIX® and BIOPLANT®) and two substrates formulated from sugarcane bagasse and filter cake (SABAFI and SUSBAFI) combined with bud chip from the basal and apical regions. The chemical and physical-hydric properties of the substrates and the development of PSS were evaluated. The substrates evaluated provided contrasting environments for root growth in relation to the physical-hydric and chemical properties. The use of by-products from the sugarcane industry can be added to the formulation of substrates for the production of pre-sprouted sugarcane seedlings, although the commercial substrate TRIMIX® provides superior performance to the seedlings, regardless of the origin position of the bud chip.

Pequi is propagated mainly by the seminal pathway (seminal route) and presents an uneven and reduced germination. The increasing demand for fruits and seedlings for reforestation indicate the need for new strategies for the propagation of this species which would minimize the negative impact of predatory extractivism on Caryocar brasiliense. The present study aimed to assist the development of a protocol for the cutting of the pequi tree (pequizeiro). Different ages of the matrix plant and levels of foliation and pruning were assessed through the collection (sampling) of cuttings (stakes) from plants in the field. It was noted that cuttings (stakes) from seedlings (young plants) have greater rooting capacity when compared to cuttings derived from adult plants. Pequi leafless stakes failed to root. In contrast, stakes with 50% of leaflets cut from their original size showed 2.5% of rooting whereas those with 6 leaflets showed 22.5% of rooting. Stakes from pruned apical branches exhibited 21.2% of rooting. Both callogenesis and rooting of pequi stakes demonstrated the potential of this particular species from the Cerrado (Brazilian savanna) for cutting.

The Cerrado is one of the most important regions for agricultural development in the world and is the main productive breadbasket of the Americas. One of the main agricultural activities in the region is high-tech livestock. Cerrado soils are predominantly low in fertility, and arbuscular mycorrhizal fungi play a fundamental role in plant nutrition in this biome. Understanding the behavior of mycorrhizal fungi in the soil under pasture is essential for the development of more efficient and sustainable management practices. Thus, this work aims to verify the activity of arbuscular mycorrhizal fungi in different species of forage grasses cultivated in cerrado soil. To measure mycorrhizal activity, soil spore density factors and mycorrhizal colonization rates in roots of 14 forage grass genotypes were investigated. No significant differences were identified in spore density values between the investigated genotypes. Panicum maximum cv and Mombasa showed the lowest values of mycorrhizal colonization, and the highest values were found in the roots of Brachiaria decumbens. Among the identified genera associated with the rhizosphere of the genotypes studied, Gigaspora, Scutelospora and Sclerocysts are less frequent, which indicates that the association with these fungal genera is less recurrent than with the others.