Jussara Maria Ferrazza

Altura de manejo de papuã e propriedades de solo em sistema de integração lavoura-pecuária

No sul do Brasil, ha ocorrencia espontânea de papua (Urochloa plantaginea (Link) R.D. Webster), nas lavouras, no periodo de verao, sendo que essa planta possui grande potencial forrageiro. Neste trabalho, objetivou-se avaliar as alteracoes ocorridas nas caracteristicas fisicas e na materia orgânica do solo, em pasto de papua, com diferentes alturas de manejo, na presenca e na ausencia de pisoteio animal. O trabalho foi realizado na Estacao Experimental do IAPAR, no municipio de Pato Branco, Parana. O delineamento experimental utilizado foi o de blocos casualizados com tres repeticoes. Os tratamentos foram arranjados em esquema bifatorial, com parcelas subdivididas, durante o periodo de pastejo. As parcelas receberam os niveis do fator altura de manejo de pasto de papua (0,1; 0,2; 0,3 e 0,4 m), enquanto as subparcelas foram constituidas de areas com (pastejadas por cabras) e sem pisoteio animal (corte manual). Foram avaliados, apos o periodo de pastejo, os teores de materia orgânica, a densidade, a porosidade total, a macro e a microporosidades do solo. De maneira geral, a altura de manejo do papua, na presenca, ou nao, de pisoteio animal, nao alterou significativamente as caracteristicas fisicas e a materia orgânica do solo, avaliadas apos o primeiro ciclo de aplicacao dos tratamentos. O pisoteio animal nao causou compactacao adicional e, mesmo com pastejo animal, os teores de materia orgânica no solo mantiveram-se altos.

Application limestone forms and doses for Alfalfa in no-tillage system

Alfalfa (Medicago sativa L.) requires good soil fertility. Brazil is characterized by acidic soils which reduce the potential of the crop. Generally, liming is incorporated into the soil, but in tillage systems it is inadvisable. This study aimed to evaluate the effects of the lime application method and dose on pH, Al+3, V % and Ca+Mg in the soil and on dry matter yield of alfalfa cultivated under a consolidated no-tillage system. The experiment was conducted at the Experimental Station of Parana Agronomic Institute, located in Pato Branco city, in Parana state. The plots consisted of the types of lime application (plowing+harrowing, subsoil and surface), the sub-plots was the lime dose (0, 2, 4, 6 and 8 Mg ha-1) and the sub-sub-plots were the sampled soil depth (0-5; 5-10; 10-20 and 20-30 cm). The results show the application of lime, even superficially, caused increases in pH, concentration of Ca and Mg and base saturation of the soil, while also reducing the concentration of Al, especially in the surface layers of the soil. The practice of plowing and harrowing or of subsoiling, with the aim of lime incorporation in a consolidated no-tillage system is unnecessary. If it is required, the application of lime to the soil should be done superficially for alfalfa cultivated in this system.

Produção de forrageiras anuais de inverno em diferentes épocas de semeadura

This study was carried out in order to evaluate the productive characteristics of annual winter forages (Avena strigosa Schereb, Lolium multiflorum Lam, Avena sativa, Triticum aestivum, Secale cereale and Triticosecale Wittmack), on four sowing dates (11 March, 8April, 6 May and 3 June 2009). The work evaluated the number of days to first harvest, the number of harvests, days of pasture usage, plant and tiller density, total production, residual dry matter and production per harvest. There was significant interaction between forages and sowing dates for all the variables analysed, which makes possible altering forage planning, combining each forage type with its best sowing date and directing forage production in order to fill any gaps. One option is the sowing of oats at the beginning of March, more conveniently supplying fodder to animals in the autumn relative to its being sown in April, even though this represents greater total forage production. However, if the greatest need for forage is in the spring, the best combination would be ryegrass sown in June. White oats, ryegrass, and oats IAPAR 61, are materials which have a high capacity for fodder production and distribution, especially when sown by the beginning of May.