The cultivation of sugarcane uses different cropping systems that result in varying quantities of crop waste, this may influence soil erosion. The objective of this study was to evaluate the loss of soil and water, the infiltration rate, and soil surface roughness in an area cultivated with sugarcane (Saccharum spp.). Six treatments with different levels of plant waste were evaluated: sugarcane without plant waste; sugarcane with 4.0 Mg ha -1 of waste; sugarcane with 8.0 Mg ha -1 of waste; sugarcane with 12.0 Mg ha -1 of waste; sugarcane with 16.0 Mg ha -1 of waste; and burned sugarcane. The treatments were arranged in a randomized block design with four replications, totalling 24 experimental plots. As soil depth increased, there is reduction in macroporosity, total soil porosity, organic carbon content, mean geometric diameter and weighted mean diameter of the soil aggregates, whereas the bulk density of the soil displays the opposite trend. The presence of sugarcane waste on the soil surface increases the time required for the initiation of surface runoff. Sugarcane waste does not alter soil surface roughness, and at the minimum amount of waste administered (4 Mg ha -1 ) reduces losses of soil and water and increases the infiltration rate. The lack of soil surface coverage after harvesting the sugarcane contributes to soil and water loss, and reduces the rate of stable infiltration of water into the soil. Key words: Saccharum spp. Simulated rain. Soil and water loss. ResumoO cultivo da cana-de-açúcar utiliza diferentes sistemas de colheita, resultando em quantidades variadas de resíduos vegetais, que podem influenciar no processo erosivo. O objetivo foi avaliar as perdas de solo e de água, a taxa de infiltração e a rugosidade superficial do solo em área cultivada com cana-deaçúcar (Saccharum ssp.). Foram utilizados seis tratamentos com diferentes níveis de resíduos vegetais: cana crua sem resíduo vegetal; cana crua com 4,0 Mg ha -1 de resíduo; cana crua com 8,0 Mg ha -1 de resíduo; cana crua com 12,0 Mg ha -1 de resíduo; cana crua com 16,0 Mg ha -1 resíduo e cana queimada. Os tratamentos dispostos no esquema experimental de blocos casualizados, com quatro repetições, totalizaram 24 parcelas experimentais. Com o aumento da profundidade do solo verifica-se redução da macroporosidade, da porosidade total do solo, do teor de carbono orgânico, do diâmetro médio geométrico e do diâmetro médio ponderado dos agregados do solo enquanto os valores de densidade do solo apresentam comportamento inverso. A presença de resíduos vegetais de cana-de-açúcar sobre a superfície do solo aumenta o intervalo de tempo necessário para o início do escoamento superficial. A palhada de cana-de-açúcar não altera a rugosidade superficial do solo e a quantidade mínima avaliada,

Resumo -O objetivo deste trabalho foi avaliar, sob chuva simulada, o efeito da cobertura vegetal sobre a erosão de um Argissolo Vermelho, no Estado de Mato Grosso do Sul, nos seguintes sistemas de cultivo: soja, com preparo convencional; soja, em plantio direto; pastagem estabelecida, sem pisoteio animal; e condição de solo exposto, como padrão de comparação. A cada 20 dias, foram tiradas fotografias digitais para a estimativa da cobertura do solo, e chuvas simuladas de 60 mm h -1 foram aplicadas às parcelas experimentais, com uso do simulador portátil de chuvas. As perdas de solo, quantificadas a cada 2 min, variaram de 3,10 a 11,40 Mg ha , no cultivo de soja sob plantio direto. As perdas de solo diminuíram com o aumento da cobertura vegetal. Na pastagem, a máxima cobertura foi de 98,10%. Os efeitos benéficos do preparo convencional são temporários, o que torna o solo mais suscetível à erosão do que os sistemas conservacionistas.Termos para indexação: Glycine max, Urochloa ruziziensis, perda de solo e água, chuva simulada. Hydraulic erosion in different tillage systems and soil coverAbstract -The objective of this work was to evaluate, under simulated rainfall, the effect of soil cover on the erosion of a Typic Hapludalf erosion, in the state of Mato Grosso do Sul, Brazil, in the following crop systems: soybean, under conventional tillage; soybean, under no-tillage; established pasture, without cattle trampling; and exposed soil, as a comparison standard. Digital photographs were taken every 20 days for soil cover estimate, and 60 mm h -1 simulated rainfall was applied on the experimental plots, using a portable sprinkler infiltrometer. Soil losses, quantified every 2 min, ranged from 3.10 to 11.40 Mg ha -1 , in exposed soil, and from 0.03 to 0.19 Mg ha -1 , in established pasture; water losses ranged from 300 to 555 m 3 ha -1 , in exposed soil, and from 63 to 229 m 3 ha -1 , in soybean cultivation under no-tillage. Soil losses decreased with the increase in vegetation cover. In the pasture, the maximum vegetation cover was 98.10%. Conventional tillage has temporary positive effects, which makes the soil more susceptible to erosion than the conservationist systems.

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The use of alternative technologies involving biological processes, with economic and ecological gains, is desirable for both the expansion of Musa spp. farming and the renovation of areas with low yields. Arbuscular mycorrhizal fungi (AMF) can stimulate plant growth, especially by increasing the absorption of phosphorus (P) and other nutrients. This study analyzes the influence of AMF on the growth and physiology of micropropagated Musaspp. plants submitted to doses of P. The experimental design was randomized blocks, in a 5 x 5 factorial arrangement, in which the factors were inoculation with AMF (Glomus clarum, Gigaspora margarita, , Gigaspora albida,Clareoideoglomus etunicatum, and the control without AMF) and five doses of P (0, 50, 100, 200, and 400 mg kg-1), with four replicates. The application of P doses increased growth in micropropagated Musaspp. seedlings, regardless of mycorrhizal inoculation. The highest rates of mycorrhizal colonization occurred at the lowest P doses, and the dose of 50 mg kg-1 P provided better conditions for mycorrhizal formation in all AMF species under study. The symbioses with AMF, as well as the use of P, increased photosynthesis rate, thus favoring the growth, development, and quality of Musa spp. seedlings. Species G. clarum, C. etunicatum, and G. margarita were the most promising for plant growth.