Green and sweet corn grown under different cover crops and phases of the no-tillage system

ABSTRACT Special corn is cultivated all year conventionally round; however, its productivity increases when grown under a no-tillage system (NTS). This study aimed to evaluate the agronomic performance of sweet and green corn cultivated under residues of different cover crops and the NTS implantation stages. Two experiments were carried out in the randomized block design, with four replications, in each of the three areas. The experiments consisted of evaluating the sweet and green corn, simultaneously, in three areas at different stages of development of NTS: initial (1 year), transition (7 years), and consolidation (19 years) with six types of cover crops: Signal grass (SG), Pearl millet (PM), Sunn hemp (SH), a mixture of SG + SH, SG + PM, and PM + SH. The dry matter (DM) production of the cover crops, the productivity of husked and unhusked ears, straw, and grain yield were evaluated. The SH had the highest dry mass production among the studied cover crops in all phases of the NTS. The phase of the NTS did not influence the productivity of ears with or without husk in green corn. The cultivation of sweet corn in transition and consolidation areas of the NTS showed better yields when compared to the initial phase of the system.

No-tillage implementation: Analyzis on water-based sediment flow in the Marombas River, Brazil

ABSTRACT Water erosion is influenced by climate, soil, soil cover and soil conservation practices. These factors can be modified by natural (especially climate) and/or anthropogenic (especially soil, soil cover and conservation practices) actions. The relief factor also influences the water erosion and can also be partially modified by anthropic action. This study aimed to evaluate the impact of anthropogenic action due to the introduction of soil crop in no-tillage system on water erosion, and on the consequent flow of sediments in the water. The study was carried out in the Marombas river basin with an area of 3,939 km², using the Soil Water Assessment Tools (SWAT) model. The calibration and validation of the model for sediment production was carried out with a historical series of synthetic data. The data from this series were estimated by linear regression from sediment value load and the average daily flow obtained punctually in the basin’s outlet. The SWAT model was calibrated on a daily scale with data from 1979 to 1989 and was validated with data from 1994 and 1997. The SWAT model was suitable to represent the average daily flow and sediment flow in the Marombas watershed. The hypothesis of reduced sediment production with increasing soil crop in no-tillage system was accepted.

Long-Term Monitoring of Different Field Traffic Management Practices in Cereals Production with Support of Satellite Images and Yield Data in Context of Climate Change

Cereals in Europe are mainly grown with intensive management. This often leads to the deterioration of the physical properties of the soil, especially increasing bulk density due to heavy machinery traffic, which causes excessive soil compaction. Controlled traffic farming (CTF) technology has the potential to address these issues, as it should be advantageous technology for growing cereals during climate change. The aim of this study was to compare the yield potential of CTF and standardly used random traffic farming (RTF) technology using yield maps obtained from combine harvester and satellite imagery as a remote sensing method. The experiment was performed on a 16-hectare experimental field with a CTF system established in 2009 (with conversion from a conventional (ploughing) to conservation tillage system). Yield was compared in years when small cereals were grown, a total of 7 years within a 13-year period (2009–2021). The results show that CTF technology was advantageous in dry years. Cereals grown in the years 2016, 2017 and 2019 had significantly higher yields under CTF technology. On the contrary, in years with higher precipitation, RTF technology had slightly better results—up to 4%. This confirms higher productivity when using CTF technology in times of climate change.

The Combined Effect of Biochar and Mineral Fertilizer on Triticale Yield, Soil Properties under Different Tillage Systems

This study examined the effect of study time, biochar dose, and fertilization-tillage system on the improvement of sandy loam physical-chemical properties and triticale grain yield. The soil properties (water holding capacity (WHC), wettability, moisture content (MC), organic matter content (SOM), pH, and electrical conductivity (EC) were monitored in short time intervals (after 3, 6, 12, and 24 months). Soil was tilled in two methods (shallow ploughless tillage and direct drilling), fertilized with nitrogen, phosphorus, and potassium (NPK) fertilizers, and amended with three hydrophobic pine wood biochar doses (0 t/ha; 5 t/ha; 15 t/ha). It was found that 15 t/ha biochar dose had the highest effect on the soil’s physical-chemical properties improvement (SOM increased by 33.7%, pH—by 6.84%, EC—by 23.4%, WHC—by 8.48%, and MC—by 21.8%) compared to the variants without biochar. Direct drilling, fertilization with NPK fertilizers and 15 t/ha biochar dose significantly influenced the rise of soil’s physical-chemical properties and triticale yield (3.51 t/ha).

Rotation/Succession Systems Affects Springtails (Hexapoda: Collembola) Abundance in Cash Crops Under No Tillage Cultivation

Acknowledging the bio indicator importance of springtails (Hexapoda: Collembola) for soil quality, this study aimed to determine the abundance of these arthropods in different systems of rotation/succession with commercial and cover crops, while also verifying the agricultural factor associated to these arthropods’ population. In the Instituto de Desenvolvimento Rural do Paraná (IAPAR-EMATER), during six years, areas with differing crops in rotation/succession adopting the no-tillage system were studied. For each system, chemical analyses of the soil were conducted and the number of captured springtails in pitfall traps was counted. The phytosanitary products applied during the evaluations and the quantity of vegetal cover remaining after harvest were considered as well. No difference was found between the rotation/succession systems in relation to chemical soil attributes, however the largest number of springtails was found in crop covers from corn, Brachiaria sp., and canola. These crop covers, including wheat, resulted in the highest straw dry mass. When removing the system in which the predecessor crop had the highest quantities of fungicide application, a positive correlation (r = 0.63; p < 0.01) was found, between springtail abundance and highest amount of straw after the harvest. If no fungicide applications occur, the crops with the largest amount of vegetal cover favor springtail populations.

Effect of Cover Crops Associated With Lettuce Production Under No-Tillage System

The use of cover crops has benefits for the chemical, physical and biological properties of the soil. However, together with the need for good vegetable productivity, considerable challenges arise in several regions of Brazil. The preparation of conventional soil for initiating no-tillage systems is necessary to create a management history and assimilate the benefits of the no-tillage system in vegetables, ensuring sustainable production. The objective of this research was to evaluate lettuce yield as a function of different cover crops as a function of resistance to soil penetration. The experiment was conducted in the horticulture sector of the University of Rio Verde, Rio Verde, Goiás, Brazil. The cover crops used were sunflower (Helianthus annuus), sunn hemp (Crotalaria juncea), and fallow, and the vegetable used was lettuce (Lactuca sativa). The variables analyzed were plant height and lettuce yield, straw decomposition, and soil resistance to penetration. The collected data were submitted to analysis of variance, and if significant, was compared by Tukey test (p < 0.05) and regression analysis. The lettuce height in the different management systems showed no statistical differences. The decomposition of the straw presented accentuated degradation for the evaluated cover crops and the productivity was bigger in the straw of crotalaria and fallow. Soil resistance for cover crops was not greater than 2 MPa.

Soybean (Glycine max (L.) Merr.) Growth, Yield, and Nodulation in the Early Transition Period from Conventional Tillage to Conservation and No-Tillage Systems

Soybean (Glycine max (L.) Merr.) is the most important protein crop globally, with its cultivation area in Europe on the increase. To investigate how alternative tillage systems affect soybean growth, yield performance, and nitrogen fixation capacity in the early conversion period from conventional tillage to conservation and no-tillage practices, a field study was conducted in 2020 under the humid central European climatic conditions of Slovenia. A complete randomized block design with four repetitions was used for the three different tillage systems (conventional, conservation, and no-tillage). The results show that the majority of the studied soybean growth parameters (e.g., plant density, nodes per plant, and shoot and root dry matter) and the yield components (e.g., pods per plant, and 100-seed mass) were greatest for the reference conventional tillage system. The conventional system also showed significantly greater dry nodule mass (p < 0.01) and proportion of large-sized nodules (>4 mm) on both the tap root (p < 0.05) and the lateral roots (p < 0.001). A positive linear correlation between nitrogen content and nodule production in the roots also suggested increased nitrogen fixation for the conventional system. The less intensive conservation and no-tillage systems resulted in significantly greater soil compaction, which negatively affected early plant establishment and resulted in significantly decreased plant densities. Despite the large differences in plant stands and individual plant performances, no significant differences were seen for dry seed yields between these tillage systems. Dry seed yields for the conventional and conservation systems were 4.54 and 4.48 t ha−1, respectively, with only minor (non-significant) yield reduction for the no-tillage system, at 4.0 t ha−1. These data show that soybean cultivation in the early transition period to less intensive tillage systems have no major yield losses under these less suitable agro-climatic conditions if correct crop and weed management measures are implemented.