No-till practices have not been widely adopted by vegetable producers due to the necessity of seedbed preparation to incorporate organic fertilizers and plant residues of the preceding crops. This study evaluated biomass yield and residue decomposition of different cover crops, and their influence on agronomic performance of Brassica crops cultivated under no-till system. The experiment was laid out in randomized complete blocks with 4 x 3 factorial treatment combinations of four cover crops: Sunn hemp (SH), Signal grass (SG), Pearl millet (PM), and SH + PM mixture, and three doses of mineral fertilizer-0, 50, and 100% of the recommended fertilizer doses for broccoli. The same design and treatments were used for cauliflower and then for cabbage, separately.. The experiment was carried out with 4 repetitions on parcels of 20 m 2 . No beds were raised, for the planting of seedlings was done in pits. The following agronomic traits were evaluated: Dry biomass (DB) and decomposition of cover crop residues (DR), and the number of leaves (NL), height (H), fresh head weight (FHW) and dry head weight (DHW), and yield (Y) of Brassica crops. The highest DB occurred in treatments with SH (Give value). SG presented the highest DR constant and the shortest half-life of residues in this study.; Broccoli presented better agronomic performance when cultivated on residues containing SH.; Fertilizer doses influenced broccoli and cabbage productivity, which were the highest for the treatment with 100% dose of mineral fertilizer.

The decomposition and release of nutrients from plant residues that precede the cultivation of vegetables can positively affect the morphological parameters and crop productivity. The objective of this study was to evaluate the effects of plant residue decomposition and the cycling of macro and micronutrients of four cover crops preceding the broccoli production (single head Avenger hybrid). A 4x3 factorial scheme was implemented including four cover crops: signal grass (SG), pearl millet (PM), sunn hemp (SH), mixture PM+SH; and three doses of mineral fertilizer: 0, 50 (200 kg ha-1 of P2O5, 50 kg ha-1 of K2O, 75 kg ha-1 of N) and 100% of the recommended fertilizer dose (400 kg ha-1 of P2O5, 100 kg ha-1 of K2O and 150 kg ha-1 of N). Fresh (FB) and dry biomass (DB), residue decomposition, nutrient cycling of cover crops, the number of leaves, head height (HH), stem diameter (SD), head diameter (HD), head fresh-biomass (FB), head dry biomass (DB) and broccoli yield were evaluated. The FB production from PM (25.9 t ha-1), SG (23.3 t ha-1) and mixture PM+SH (23.9 t ha-1) were similar, while the largest production of DB occurred in the SG (11.9 t ha-1). The lowest rate of decomposition and the greatest half-life time of residues occurred where PM was present. The accumulation and nutrient cycling follow the sequence K>N>Ca>Mg>P>S and Mn>Zn>B>Cu for all cover crop treatments evaluated. The highest SD (51.95; 51.44 and 50.67 mm), HD (187.97; 187.41 and 183.48 mm), FB (1.01; 1.00 and 0.97 kg), DB (0.08; 0.07 and 0.07 kg) and broccoli yield (25.3; 24.9 and 24.7 t ha-1) was observed in the 100% dose of mineral fertilizer and on the residues of SH or PM+SH mixture, respectively.

Currently, the environmental appeal to promote reforestation programs, recovery of degraded areas and preservation of biodiversity pressures the production sector of native forest essences' seedlings. Jatoba, Hymenaea courbaril L., is a native tree which provides many products of great economic relevance. Vegetative propagation is an alternative method for seedlings production, which presents many benefits, including the possibility of establishing high productivity clonal hedges, as it occurs with the Eucalyptus genus. The experiment was conducted in a greenhouse, with partial temperature and humidity control. The study assessed the effects of different dosages of indolbutiric acid (IBA) hormone in the process of rooting jatoba cuttings. The cuttings were prepared in a laboratory and submitted to different dosages of IBA (0, 200, 400, 600, 800 e 1000 mg L-1), later established in sand substrate and placed in protected environment with intermittent fogging system and shading of 50%. Statistical analysis was carried out using R software, according to experimental design in randomized blocks, with six treatments and four replications. The results obtained by binomial evaluation showed there was no significant difference between IBA dosages, so the use of IBA on rooting H. courbaril cuttings was ineffective. However, success in the vegetative propagation of jatoba can occur through the selection of individuals that present good results to adventitious rooting. The use of IBA on adventitious rooting varies from one species to another, and due to the lack of studies on the subject concerning Hymenaea courbaril L., more experiments to be carried out in order to evaluate the rhizogenic potential should be done.