Adubação nitrogenada no perfilhamento da aveia-preta em duas condições de fertilidade do solo

Abstract

RESUMO -Para testar o efeito de seis doses de N (0, 20, 30, 40, 50 e 60 kg/ha) aplicadas em cobertura, no final do perfilhamento, sobre a produção e a qualidade das sementes de Avena strigosa Schreber cv. Comum, foi conduzido um trabalho, em condições de campo, em Terra Roxa Estruturada distrófica, textura argilosa, em duas glebas com diferentes condições de fertilidade de solo. A gleba de menor fertilidade (pousio) apresentava saturação de bases (V) de 35% e a de maior fertilidade (cultivo com batata), 49%; nesta aplicou-se calcário para elevar a V para 70%. Na semeadura, foram aplicados 20, 80 e 40 kg/ha de N, P 2 O 5 e K 2 O, respectivamente. A adubação nitrogenada em cobertura não afetou nem os componentes da produção, nem a produtividade, nem a germinação das sementes, nos dois experimentos. Em condições de maior fertilidade do solo, a dose de 60 kg/ha de N provocou aumento no acamamento das plantas e diminuição do peso hectolítrico. Em condições de menor fertilidade de solo, a adubação nitrogenada ocasionou aumentos na produção de massa vegetativa seca da parte aérea, e quando na dose de 60 kg/ha, aumentou o teor de proteína das sementes.Termos para indexação: Avena strigosa, semente, nitrogênio, acamamento, matéria seca, partes aéreas, peso. NITROGEN FERTILIZATION AT TILLERING OF BLACK-OAT IN TWO SOIL FERTILITY CONDITIONSABSTRACT -The objective of this work was to study the effect of six doses of N (0, 20, 30, 40, 50 and 60 kg/ha) applied at the end of tillering stage, on yield and seed quality of Avena strigosa Schreber cv. Comum, under two conditions of soil fertility. The experiments were carried out under field conditions on a Ultisol (distrophic Terra Roxa Estruturada), in Botucatu, SP, Brazil. The soil with less fertility (fallow land) presented 35% of soil base saturation. The soil with high fertility (previously with potato crop) had 49% of soil base saturation and received lime to increase it to 70%. All plots received basal fertilization of 20, 80 and 40 kg/ha of N, P 2 O 5 and K 2 O. The yield and seed germination were not affected by N top dressing under both soil conditions. Under high fertility soil, the 60 kg/ha of N dose gave rise to the lodging and the decrease of the hectolitric weight of the seeds. Under less fertility soil, the N fertilization increased the dry weight of aerial part and improved the seed protein content at the highest dose of N.

Rates of nitrogen and growth retardant trinexapac-ethyl on wheat

“…Increase in plant lodging in response to N rates corroborates the results reported for oat (NAKAGAWA et al, 2000). The rise in N supply stimulates vegetative growth (BUZETTI et al, 2006), reduces tissue hardness and, among other agronomic effects, contributes to increase in grain yield (COELHO et al, 1998;TEIXEIRA FILHO et al, 2007).…”

IPR 126 white oat forage potential under free growth, cutting and grazing at two management heights

“…Most published papers on tillering with oats have been carried out aiming at evaluating seeds production (Nakagawa et al, 2000;Reichardt et al, 2008). Tillering in forage grasses has been described as the most important feature to establish productivity of these crops (Simon & Lemaire, 1987).…”

Forage production dynamics of winter annual grasses sown on different dates

“…Nakagava et al (2000) planted common black oat in June and counted 87.5 plants/m² less than Rosseto & Nakagava (2001) At the first sowing date, common black oat and ryegrass had a higher tiller population density ( Table 6 -Tiller population density (tillers/m 2 ) of annual winter grasses on different sowing dates morphology and smaller leaves and tiller in relation to other forage cultivars. Similarly, at the second sowing date, these materials had a higher tiller population density, the same of IPR 126 oat.…”