Mimosa caesalpiniifolia intercropping, weeds removal and nitrogen fertilization on maize

Abstract

Weeding is expensive and laborious, and some weeds may re-establish themselves afterwards. Arboreal leguminous plants can control weeds, and fertilization with nitrogen can increases the competitive ability of the maize. The aim of this work was to evaluate the effects of weed-removal and intercropping with sabiá (Mimosa caesalpiniifolia) on control of weed plants and maize productivity. A randomized complete block design in a split-plot arrangement was used with five replications. Cultivar AG 105, fertilized with nitrogen (30 and 120 kg/ha of N applied to the plots) was subjected to the following treatments (subplots): A) no weeding; B) intercropping with sabiá (30 viable seeds/m2, broadcast between the rows of maize); C) hoeing {20 and 40 days after sowing (DAS)} with no removal of weeds (nROW); D) two hoeings at 20 and 40 DAS with ROW at 20 DAS; E) two hoeings at 20 and 40 DAS with ROW at 40 DAS; F) and two hoeings at 20 and 40 DAS with ROW after each hoeing. Increasing the dose of nitrogen reduced the growth of the sabiá (30%) and weeds (32%) and increased the corn green ear yield (115%) and grain yield (40%) of maize. Sabiá did not reduce the growth of weeds, but it was beneficial to corn because increased the number of green ears. Carrying out two hoeings, with or without the removal of weeds, reduced weed growth (92%) and provided the highest yields of green ears (5.6 t/ha) and grains (6.0 t/ha).

Economic nitrogen doses via fertigation for corn cultivation in a semiarid environment

“…In a study using irrigated corn in Mossoró, Rio Grande do Norte State, Brazil, Silva et al (2014) obtained a maximum estimated grain yield (7,480.00 kg ha -1 ) at the recommended dose of 88 kg ha -1 N for the production of hybrid AG 1051. In the same edaphoclimatic conditions and using the hybrid AG 1051, Silva, Braga, Ribeiro, Oliveira, and Santos (2010), Silva, Oliveira, Silva, Chicas, and Tomaz (2015), and Monteiro, Silva, Tavella, Oliveira, and Silva (2016) reached average grain yields of 5,094.00; 6,264.00; and 6,332.00 kg ha -1 , respectively, with a dose of 120 kg ha -1 N. These productivities were superior to the present research and can be justified by the use of NH 3 sulfate instead of urea (Barros, Santos, Pacheco, Procópio, & Souza, 2016), reducing possible N loss by NH 3 volatilization and sulfur availability, in addition to the use of phosphate fertilization (60 to 120 kg ha -1 P 2 O 5 ) and potassium (30 to 50 kg ha -1 K 2 O) in the foundation.…”

Economic nitrogen rate for fertigation of green corn crop in the Brazilian semiarid

“…Studies have shown the beneficial effect of N rates via manual or mechanical fertilizer distribution on the yield of green corn (Silva et al, 2000(Silva et al, , 2013Paiva et al, 2012;Freire et al, 2010;Araújo et al, 2014;Dantas et al, 2014;Monteiro et al, 2016). However, published article on the application of fertilizers by water (fertigation) in green corn in Brazil were not found, although many corn producers in the country's semiarid already use this technique in drip-irrigation systems, seeking to reduce costs with labor, facilitate the splitting of rates, and increase the uniformity of distribution of fertilizers.…”