Resumen En este estudio fueron evaluados los efectos de las dosis de fósforo y de estiércol bovino sobre el crecimiento de melón (Cucumis melo L.) cv Galia, cultivado en casa de vegetación utilizando macetas con suelo Luvisol crómico. El experimento fue realizado con un delineamiento completamente casualizado con esquema factorial 5x2, constituido por cinco dosis de estiércol bovino (0, 12, 16, 20, 24 t ha-1) y dos dosis de fósforo (0 y 400 mg dm-3) con tres repeticiones, totalizando 30 unidades experimentales. Los resultados indican que hubo efecto significativo de la interacción del fósforo con la materia orgánica sobre la masa seca total del melón. Cuando las plantas fueron sometidas a mayores dosis de estiércol hubo una reducción de la masa seca total. Los contenidos de P en la hoja y en el tallo aumentaron gradualmente con las dosis más altas la mayor dosis de fósforo. Los niveles de fósforo en el suelo aumentaron de acuerdo con las dosis de materia orgánica disponible.

Abstract It was aimed to evaluate the effect of doses of phosphorus and different doses of bovine manure on growth of melon Galia. The experiment was carried out in greenhouse utilizing pots filled with soil Chromic Luvissoil in design completely randomized with a 5 x 2 factorial arrangement, comprising five doses of bovine manure (0, 12, 16, 20, 24 t ha-1) and two doses of phosphorus (0 and 400 mg dm-3), with three replicates, totaling 30 experimental units. The results indicated that interaction of phosphorus with organic matter was significant effect on total dry mass of the melon plant. There was a reduction of the total dry mass when the plants were fertilized at the highest doses of bovine manure. The P content from leaf and stem increased gradually at higher doses of phosphorus. The phosphorus content in the soil increased according to the doses of organic material available.

Resumo A compostagem é uma alternativa para reciclagem de resíduos orgânicos biodegradáveis, transformando-os em adubo orgânico que podem ser utilizados como aporte de nutrientes para fins agrícolas, evitando sua deposição em aterros sanitários. O objetivo do presente estudo foi avaliar a compostagem de resíduo orgânico doméstico em substituição ao esterco de bovino, com vista a sua aplicação na adubação do tomateiro cereja (Solanum lycopersicum Mill., var. cesariforme). Nesse sentido, foram construídas pilhas de compostagem com 30% de resíduos orgânicos (fonte de carbono) e 70% resíduos de podas de árvores (material de enchimento). Foram testadas duas fontes de resíduo orgânico: resíduos alimentares de origem doméstica (FW) e esterco bovino (CM), em cinco proporções (15% FW + 15% CM, 10% FW + 20% CM, 20% FW + 10% CM e os controles 30% CM e 30% FW). Após 90 dias, o composto maturado de cada pilha foi misturado com substrato de fibra de coco na proporção de 1:1 e acondicionado em vasos plásticos de 15 L, onde as plantas de tomateiro cereja foram cultivadas. O experimento foi conduzido em casa de vegetação utilizando o delineamento experimental de blocos casualizados, com cinco tratamentos e cinco repetições. Foram realizadas avaliações de crescimento e composição mineral do tecido foliar do tomateiro cereja. Os resultados indicam que o esterco bovino pode ser substituído por resíduos alimentares como material orgânico para construção das pilhas de compostos. A adubação com composto orgânico oriundo de resíduos alimentares influenciou positivamente no crescimento e assimilação dos nutrientes no tecido foliar do tomateiro cereja.

Abstract Composting is an alternative for recycling biodegradable organic waste, transforming it into organic fertilizer that can be used as agricultural nutrients, avoiding its disposal in landfills. This study evaluated the composting of household organic waste as a substitution for cattle manure, with a view to its application in the fertilization of cherry tomatoes (Solanum lycopersicum Mill., Var. Cesariforme). Thus, compost piles were set up using 30% organic waste (carbon source) and 70% tree-pruning residues (filling material). Two sources of organic waste were tested: household food waste (FW) and cattle manure (CM), at five proportions (15% FW + 15% CM, 10% FW + 20% CM, 20% FW + 10% CM and the controls 30% CM and 30% FW). After 90 days, the mature compost from each pile was mixed with coconut fibre in a 1:1 ratio and used as substrate filled in 15 L plastic pots, where the cherry tomato plants were grown. The experiment was conducted under greenhouse conditions in a randomized block design, with five treatments and five replicates. Assessments of growth and leaf mineral composition were performed for the cherry tomato plants. The results indicate that cattle manure can be replaced by household food waste as the organic material used in compost piles. Fertilization with organic compost from household food waste positively influenced the growth and nutrient assimilation in the leaf tissue of cherry tomato.

ABSTRACT We evaluated two areas of sustainable management within the Caatinga and one area of conventional agricultural cultivation to compare their physicochemical attributes with those of native forest. The management strategies were as follows: (1) thinning of savanna; (2) thinning of strips; (3) conventional tillage with plowing and harrowing; and (4) native forest. The main indicators of physicochemical quality of the environments were bulk density, porosity, clay amount, phosphorus content, cation exchange capacity, and organic matter. The use of soil for agricultural purposes resulted in a reduction of soil organic matter, regardless of the tillage system. Even though the management strategy, which involved thinning of savanna, further increased the soil phosphorus content and compaction, it did not reach critical values that limit crop development.