Structural and productive characteristics of Marandu and Xaraés grasses fertilized at different times after harvesting

Abstract

-The objective of this study was to assess the effect of applying N and K 2 O at different times after harvest on the structure and production characteristics of Marandu and Xaraés cultivars of Brachiaria brizantha. Two greenhouse 4 × 2 factorial experiments using a randomized block design with eight treatments and four replicates were carried out. In experiment 1, the plants in pots were fertilized weekly with 50 mg/dm 3 of N and K 2 O until a week before a uniformity cut, for a total of four applications. After cutting, plants were fertilized with 50 mg/dm 3 of N and K 2 O at 0, 3, 6, and 9 days. Cultivars were evaluated after 44 days of regrowth. In experiment 2, a single 50 mg/dm 3 dose of N and K 2 O was applied a week before the uniformity cut, and 100 mg/dm 3 of N and K 2 O were applied at 0, 4, 8, and 12 days after cutting; cultivars were evaluated after 39 days of regrowth. In experiment 1, the leaf/stem ratio and dry matter yield were influenced by the time at which fertilizers were applied. In the second experiment, the total number of leaves, expanded leaves, dead leaves, and the leaf lamina accumulated length and dry matter production were influenced by the time at which fertilizers were applied. Marandugrass had more leaves and tillers than cv. Xaraés, which, in turn, had greater height, dry matter yield and regrowth vigor. Applying nitrogen and potassium fertilizer immediately after cutting improves the structural characteristics, while the dry matter yield is maximized by applying fertilizers immediately after cutting by using lower doses of N, or at 4.5 days after cutting by using higher doses of N.

Productive and morphophysiological responses of Panicum maximum Jacq. cv. BRS Zuri to timing and doses of nitrogen application and defoliation intensity

“…Different results were obtained by Pereira et al. () when studying the cultivars marandu and xaraés of Urochloa brizantha Trin. The concentration of N in the plants did not change with the time of N application, but the forage production was higher when the fertilization was performed approximately 4 days after the cut.…”

“…Pereira et al. () also did not report changes in the number of tillers in the U. brizantha cultivars marandu and xaraés in response to N application 4 days after the beginning of regrowth. Although this response is difficult to explain, notably, the opposite effect was observed on the root mass, as already discussed.…”

“…fertilized with N compared to that of unfertilized plants. A large part of this response comes from the strong effect of N on grass tillering (Marques et al., ; Pereira et al., ). Garcez‐Neto, Gobbi, Silva and Santos () reported that under higher N doses, a reduction occurs in the mobilization of stem base stocks and roots of the P. maximum cv.…”

Impactos Técnico-Econômicos Da Adubação De Pastos

“…Para o capim Piatã recomenda-se que a adubação seja feita o mais próximo da desfolha, ou seja, logo após a saída dos animais do piquete, pois em adubação tardia evidencia-se redução na massa de forragem (FARIA et al, 2019). Contudo, para os capins Marandu, Xaraés, BRS Quênia, BRS Zuri, Massai existe pouco efeito da época de adubação sobre a massa de forragem, o que garante mais flexibilidade no manejo da adubação (PEREIRA et al, 2012;MARQUES et al, 2016;GOMIDE et al, 2019;FARIA et al, 2019). É provável que a maior flexibilidade quanto ao momento de realizar a adubação nitrogenada esteja associada ao baixo teor de reservas nitrogenadas na base do colmo e raízes das gramíneas forrageiras.…”

Wood ash and water availability in the production of Paiaguás-grass

“…The aerial-part dry mass has a positive correlation with the structural characteristics of grasses, such as the number of leaves, tillers and leaf area (Megda and Monteiro, 2010), important aspects to define the most adequate management of pastures (Pereira et al, 2012).…”