Grasses and Legumes as Cover Crops Affect Microbial Attributes in Oxisol in the Cerrado (Savannah Environment) in the Northeast Region1

Abstract

The cover crop straw may cause changes in the microbial activity and population, with repercussions on environmental changes and on the C and N dynamics, providing important information for the planning of adequate land use in the Cerrado. The objective of this study was to evaluate the effect of straw of cover crops on the soil microbial attributes and quality of organic matter. Experimental units consisted of 100 g of sieved soil placed in small plastic cups mixed with straw from cover plants. Treatments were distributed in a CRD, in a factorial scheme of 7 x 7 + 1, with seven types of straw, evaluated at 7, 14, 21, 28, 42, 63 and 105 days after incubation, and control without straw, with three replicates. The qCO2 ranged from 0.1 (Crotalaria spectabilis at 14 days) to 5.1% (Cajanus cajan ‘IAPAR 43’ at 42 days). The organic carbon and nitrogen reservoir are differently affected by straw of legumes and grasses on the dates. The incorporation of Brachiaria brizantha and Mucuna aterrima had a positive impact on the microbial attributes until the 21st incubation (qCO2, Cmic and Nmic), with little loss of carbon dioxide and growth of the microbial population. All the evaluated species presented a potential to be used in crop rotation systems, enabling no-tillage systems in the Cerrado of Piauí. However, it is recommended to select species according to specific purposes. Thus, the use of cover crops is an important tool for increasing the biological quality of Brazilian northeastern cerrado soils.

Silicon mitigates the effects of moderate drought stress in cover crops

“…Cover crops are well known for their positive effects on soil such as erosion processes, physical properties, organic matter, microbial population, nutrient cycling, potassium (K + ) and nitrate (NO 3 – ) leaching and weed populations (Almeida et al., 2018; Amorim et al., 2020; Surekha et al., 2006; Tardy et al., 2017). Several cover crops have been researched and used in tropical conditions; among these, forage grasses are the most studied.…”

Relations between soil attributes and the abundance of Bacillus thurigiensis in the Cerrado of Maranhão state, Brazil

“…Considering that the soils evaluated are native Cerrado, whose characteristic is low fertility, with high values of attributes linked to acidity and aluminum, and low in basic cations and phosphorus (Amorim et al, 2020), thus we can justify the contrasting result between the mentioned chemical attributes and iBt, since there is a need for an adequate pH and nutrient concentrations for a satisfactory development of microorganisms (Medhi et al, 2017), including Bt, as reported in Rabinovitch et al (2017). Furthermore, for a good conditions for bacterial growth includ temperature and pH, so in low value of pH, that represent high levels of H+Al and Al in soils of Cerrado could be explain the results founded (Kalsoom et al, 2023).…”

Grass-Legume Seeding: A Sustainable Approach Towards Reclamation of Coalmine Degraded Lands in India

“…Grass-Legume Seeding: A Sustainable Approach towards Reclamation of Coalmine Degraded… DOI: http://dx.doi.org/10.5772/intechopen.99741 A grass-legume association potentially accumulates high quality organic substrates in soil with soil organic carbon (SOC) and N pool accretion and promoting beneficial soil micro-organisms [53][54][55]. The difference in the chemical composition of grass-legume mixture incorporated in soil shifts the nutrient cycling via mineralization which stimulated the soil microbial activities [56]. Soil microorganisms are a necessary link between plant-soil interaction for productivity, nutrient availability and cycling thus, legumes are one of the necessary components to increase soil microbial activity accelerating the process of ecological restoration in mined areas [29].…”