Influence of earthworms on the microbial properties and extracellular enzyme activities during vermicomposting of raw and distilled grape marc

Financiado para publicación en acceso aberto: Universidade de Vigo/CISUGThe treatment of winery wastes by using appropriate management technologies is of utmost need in order to reduce to a minimum their disposal and avoid negative environmental impacts. This is of particular interest for grape marc, the main solid by-product of the winery industry. However, comparative studies on a pilot-scale dealing with the impact of earthworms on marc derived from both red and white grape varieties during vermicomposting are still scarce. The present study sought to evaluate the changes in the biochemical and microbiological properties of red and white raw marc in the presence and the absence of the earthworm species Eisenia andrei. The distilled marc obtained through distillation of the red grape marc was also considered under this scenario. Samples were taken after 14, 28, 42, and 63 days of vermicomposting. On day 14 earthworms led to a pronounced increase in most of the enzymatic activities, but only in those vermireactors fed with raw marc from the red grape variety. Alfa- and beta-glucosidase as well as chitinase and leucine-aminopeptidase activities were between 3 to 5-times higher relative to the control, while alkaline phosphomonoesterase was even up to 14-fold higher with earthworm presence. From day 28 onwards the magnitude of earthworms’ effect on the studied enzymes was also dependent on the type of grape marc. Reduced values of basal respiration, ranging between 200 and 350 mg CO2 kg OM h−1 and indicative of stabilized materials were found in the resulting vermicomposts. Moreover, the content of macro- and micronutrients in the end products matched with those considered to have the quality criteria of a good vermicompost. Altogether, these findings reinforce the effectiveness of vermicomposting for the biological stabilization of grape marc with the dual purpose of fertilizer production and environmental protection.Ministerio de Economía y Competitividad | Ref. AGL2017-86813-RMinisterio de Economía y Competitividad | Ref. RYC-2016-21231Xunta de Galicia | Ref. ED431B 2019/038Xunta de Galicia | Ref. ED431F 2018/0

Desempenho de sementes de feijão sob diferentes temperaturas

The study evaluated the germination performance of bean seeds (BRS Expedito) from different regions of southern Brazil submitted to different germination temperatures (20, 25 and 30º C). Were evaluated to germination (GER), first germination count (PCG), germination speed index (IVG), shoot dry mass (MSPA) and root dry mass (MSR). The seeds from São Mateus (PR) presented the highest average values for the variables GER, PCG and IVG in the three temperatures tested. The temperature increase (20 to 30 ºC) significantly influenced the dry biomass accumulation in the shoots and seedlings roots. The results indicate the existence of a phenotypic plasticity acquired by the cultivar due to local adaptation of the ecotypes.O estudo avaliou o desempenho germinativo de sementes de feijão (BRS Expedito) de diferentes regiões do sul do Brasil submetidas a diferentes temperaturas de germinação (20, 25 e 30º C). Foram avaliados: germinação (GER), primeira contagem de germinação (PCG), índice de velocidade de germinação (IVG), massa seca da parte aérea (MSPA) e massa seca da raiz (MSR). As sementes de São Mateus (PR) apresentaram os maiores valores médios para as variáveis GER, PCG e IVG nas três temperaturas testadas. O aumento da temperatura (20 a 30 ºC) influenciou significativamente o acúmulo de biomassa seca nas raízes e da parte area das platulas de feijão. Os resultados indicam a existência de uma plasticidade fenotípica adquirida pela cultivar devido à adaptação local dos ecótipos

Edaphic fauna in soil profile after three decades of different soil management and cover crops in a subtropical region

Abstract This research evaluated the effects of long-term (30 years) winter cover crops under conventional farming system and no-tillage system on edaphic fauna in a Rhodic Hapludox soil, from Paraná State, Brazil. We used three winter cover crops (black oat, hairy vetch and fallow), and as a reference a fragment of natural forest. Soil monoliths were collected at two times, one during the flowering of maize (April 2013) and the other during the flowering of soybean (January 2014). The extraction of the monoliths was carried out in three layers in the soil profile (0-10, 10-20 and 20-30 cm). Seventeen taxonomic groups were sampled. The density of the edaphic fauna is inversely related to soil depth. The winter crops associated with the no-tillage system in long-term resulted in fauna densities similar to the natural environment, with a higher density (density increase of 2.2x) at a depth of 10-20 cm in areas with black oat. At 0-10 cm depth, black oat and vetch under no-tillage systems resulted in an increase of 62% and 69% (April 2013) and 46 and 44% (January 2014), respectively, in the density of soil fauna, when compared to the same winter crops in conventional farming system

Grandes questões precedem grandes descobertas: o legado de Stephen Hawking

A resenha objetiva apresentar a obra intitulada “Breves respostas para grandes questões” de Stephen Hawking. Deus existe? Oque há dentro de um buraco negro? Deveríamos colonizar o espaço? A inteligência artificial vai nos superar? O que acontecerá com nossa espécie se não determos as mudanças climáticas? Essas e outras questões provocativas são discutidas por Hawking ao longo do livro. A obra apresenta um conteúdo inédito sobre questões que acompanham a história da humanidade, e outras questões emergentes do século XXI

Rapid bacterial community changes during vermicomposting of grape marc derived from red winemaking

Previous studies dealing with changes in microbial communities during vermicomposting were mostly performed at lab-scale conditions and by using low-throughput techniques. Therefore, we sought to characterize the bacterial succession during the vermicomposting of grape marc over a period of 91 days in a pilot-scale vermireactor. Samples were taken at the initiation of vermicomposting, and days 14, 28, 42, and 91, representing both active and mature stages of vermicomposting. By using 16S rRNA high-throughput sequencing, significant changes in the bacterial community composition of grape marc were found after 14 days and throughout the process (p < 0.0001). There was also an increase in bacterial diversity, both taxonomic and phylogenetic, from day 14 until the end of the trial. We found the main core microbiome comprised of twelve bacterial taxa (~16.25% of the total sequences) known to be capable of nitrogen fixation and to confer plant-disease suppression. Accordingly, functional diversity included increases in specific genes related to nitrogen fixation and synthesis of plant hormones (salicylic acid) after 91 days. Together, the findings support the use of grape marc vermicompost for sustainable practices in the wine industry by disposing of this high-volume winery by-product and capturing its value to improve soil fertility.Ministerio de Economía, Industria y Competitividad (España) | Ref. RYC-2016-21231Ministerio de Economía, Industria y Competitividad (España) | Ref. AGL2017-86813-RMinisterio de Economía, Industria y Competitividad (España) | Ref. CTM2013-42540-RXunta de Galicia | Ref. ED431F 2018/05Xunta de Galicia | Ref. ED431B 2019/03

Table_1_Edaphic mesofauna responses to land use change for sugarcane cultivation: insights from contrasting soil textures.docx

Land use change (LUC), specifically the cultivation of monoculture sugarcane, can negatively impact soil biodiversity, leading to a decline in soil health and ecosystem functioning. However, while studies focusing on macrofauna and microorganisms are more frequent in the literature, the impacts of LUC on mesofauna are still little known. Therefore, this study aimed to investigate the impacts of the predominant LUC for sugarcane production in Brazil on the diversity of edaphic mesofauna in soils with contrasting textures. In addition, we assessed correlations between biodiversity and soil properties chemical, biological, and physical attributes. We took samples from two sites (clayey and sandy soils) in southeastern Brazil. The sequence of LUC included i) native vegetation (NV), ii) pasture (PA), iii) sugarcane (SC), and iv) sugarcane ratoon (SCr). In the rainy season, monoliths (25 x 25 x 10 cm), soil samples were collected at 0-10, 10-20, and 20-30 cm to assess soil mesofauna, soil chemical (pH, soil organic matter, phosphorus, sulfur, potassium, calcium, magnesium, potential acidity, cation exchange capacity), physical (soil porosity) and biological (microbial biomass carbon and nitrogen) properties. The mesofauna taxonomic groups were quantified after the classification. Briefly, a total of 22 taxonomic groups were classified. The most predominant groups were non-oribatid mites, oribatid mites, and Collembola. Richness and abundance were lower in the three land uses studied (PA, SCr, SC) compared to the intercept (NV). In clayey soil, diversity decreased from NV to PA (-0.68 ± 0.27) and SC (-0.55 ± 0.27) but not to SCr. In sandy soil, land use significantly impacted the mesofauna diversity and evenness index, significantly reducing these indexes in SCr in relation to NV. Although land use change towards more intensified systems resulted in a loss of richness and abundance of soil mesofauna, sugarcane cultivation over the years can recover the diversity of mesofauna in clay-textured soils. These results provide a scientific background to better understand the LUC effects on sugarcane cultivation and support the establishment of sustainable practices that enhance soil health and biodiversity in different soil textures. This study highlights the need for tailored land management considering soil texture and biodiversity for improved ecosystem services.</p

Table_2_Edaphic mesofauna responses to land use change for sugarcane cultivation: insights from contrasting soil textures.docx

Land use change (LUC), specifically the cultivation of monoculture sugarcane, can negatively impact soil biodiversity, leading to a decline in soil health and ecosystem functioning. However, while studies focusing on macrofauna and microorganisms are more frequent in the literature, the impacts of LUC on mesofauna are still little known. Therefore, this study aimed to investigate the impacts of the predominant LUC for sugarcane production in Brazil on the diversity of edaphic mesofauna in soils with contrasting textures. In addition, we assessed correlations between biodiversity and soil properties chemical, biological, and physical attributes. We took samples from two sites (clayey and sandy soils) in southeastern Brazil. The sequence of LUC included i) native vegetation (NV), ii) pasture (PA), iii) sugarcane (SC), and iv) sugarcane ratoon (SCr). In the rainy season, monoliths (25 x 25 x 10 cm), soil samples were collected at 0-10, 10-20, and 20-30 cm to assess soil mesofauna, soil chemical (pH, soil organic matter, phosphorus, sulfur, potassium, calcium, magnesium, potential acidity, cation exchange capacity), physical (soil porosity) and biological (microbial biomass carbon and nitrogen) properties. The mesofauna taxonomic groups were quantified after the classification. Briefly, a total of 22 taxonomic groups were classified. The most predominant groups were non-oribatid mites, oribatid mites, and Collembola. Richness and abundance were lower in the three land uses studied (PA, SCr, SC) compared to the intercept (NV). In clayey soil, diversity decreased from NV to PA (-0.68 ± 0.27) and SC (-0.55 ± 0.27) but not to SCr. In sandy soil, land use significantly impacted the mesofauna diversity and evenness index, significantly reducing these indexes in SCr in relation to NV. Although land use change towards more intensified systems resulted in a loss of richness and abundance of soil mesofauna, sugarcane cultivation over the years can recover the diversity of mesofauna in clay-textured soils. These results provide a scientific background to better understand the LUC effects on sugarcane cultivation and support the establishment of sustainable practices that enhance soil health and biodiversity in different soil textures. This study highlights the need for tailored land management considering soil texture and biodiversity for improved ecosystem services.</p