Phytomass production and nutrient accumulation by green manure species

Abstract

Green manuring is recognized as a viable alternative to improve nutrient cycling in soils. The aim of this study was to evaluate the phytomass production and nutrient accumulation in shoots of the summer green manures jack bean [Canavalia ensiformis (L.) DC.], dwarf pigeon pea (Cajanus cajanvar var. Flavus DC.), dwarf mucuna [Mucuna deeringiana (Bort) Merr] and sunn hemp (Crotalaria juncea L.), under nitrogen fertilization and/or inoculation with N-fixing bacteria. A split plot design was arranged with the four Fabaceae species as main plots and nitrogen fertilization (with and without) and inoculation with diazotrophic bacteria (with and without) as the subplots, in a 2 2 factorial. The experiment was arranged as a randomized complete block design with four replications. In the conditions of this trial, the sunn hemp had the highest production of shoot phytomass (12.4 Mg ha -1) and nutrient accumulation, while the dwarf mucuna had the lowest production of shoot phytomass (3.9 Mg ha -1 ) and nutrient accumulation. The results showed no effect of nitrogen fertilization or inoculation with N-fixing bacteria on the production of shoot phytomass and nutrient accumulation, except for inoculation without nitrogen fertilization, resulting in greater P accumulation (p <0.05) in the sunn hemp and greater Zn and Mn accumulation in the dwarf mucuna. These findings indicate that N fertilization or inoculation with N2-fixing bacteria for Fabaceae are low efficiency practices in the edaphoclimatic conditions of this study. Produção de fitomassa e acúmulo de nutrientes por espécies utilizadas na adubação verdeA adubação verde é reconhecida como alternativa viável para melhorar a ciclagem de nutrientes em solos agríco-las. O objetivo deste trabalho foi avaliar a produção de fitomassa e o acúmulo de nutrientes na parte aérea de adubos verdes de verão: feijão-de-porco [Canavalia ensiformis (L.) DC.], guandu-anão (Cajanus cajanvar var. Flavus DC.), mucuna-anã [Mucuna deeringiana (Bort) Merr] e crotalária (Crotalaria juncea L.), sob efeito da adubação nitrogenada e, ou, da inoculação com bactérias fixadoras de N. Utilizou-se o arranjo de parcelas subdivididas, sendo as parcelas constituídas pelas quatro fabáceas e, as subparcelas, por um fatorial 2 2, cujos fatores e níveis foram: 733Phytomass production and nutrient accumulation by green manure speciesRev.

Decomposition and Nutrient Release Dynamics of Shoot Phytomass of Cover Crops in the Recôncavo Baiano

“…Thus, the use of cover crops, also commonly called green manures (Correia and Durigan, 2008;Balota and Auler, 2011;Xavier et al, 2013), and nutrient recycling (Giacomini et al, 2003) should be considered as strategies to increase the productive capacity of soils, which would benefit crops of economic interest in the region. Among the most-used species of cover crops are legumes because of their ability to biologically fix N in association with diazotrophic bacteria (Mangaravite et al, 2014;Mendonça et al, 2017). Furthermore, some grasses and other non-leguminous plants have proven to be effective in keeping soil covered and recycling nutrients other than N (Gama- Rodrigues et al, 2007;Pacheco et al, 2011;Torres et al, 2015).…”

Partial replacement of nitrogen fertilization with legumes in tropical pasture overseeded with temperate species for the production of steers

“…In sub-tropical and warm-temperate latitudes, a wide range of persistent warm-season perennial grasses commonly occurs as near-monoculture grass pastures or as naturally occurring, mixed-species, grass-dominated rangeland. Forage legumes are often introduced into ruminant systems in order to reduce production costs regarding biological nitrogen fixation (N) and to add nutritional value to the diet (Ferreira et al ., 2012; Foster et al ., 2014; Mangaravite et al ., 2014). Although organic N in soil is partially mineralized by microbial activity, its quantity is not enough to significantly increase pasture quality and availability to enhance animal production.…”

Sample Sufficiency for Mean Estimation of Productive Traits of Sunn Hemp

“…This legume is a shrub, standing upright 2 to 3 meters high and with deep root system, which assists in soil decompression and nutrient recycling. This species is used in crop rotation and stands out among the soil cover crops due to the P and Mg accumulation, high biomass production, reaching up to 16.5 t ha -1 of dry matter and nitrogen fixation up to 298 kg ha -1 of N (Mangaravite, Passos, Andrade, Burak, & Mendonça, 2014;Silva et al, 2014;Xavier, Oliveira, & Silva, 2017). Sunn hemp is a viable option for crop rotation in areas infested with root-knot nematodes (Meloidogyne enterolobii) (Rosa, Westerich, & Wilcken, 2015).…”