Maize Stubble Research Articles

Conservation agricultural practices promoted arbuscular mycorrhizal fungal colonization and glomalin content on sandy clay loam of southern India.

Arbuscular mycorrhizal Fungi (AMF) are essential in agriculture and are often inter-linked with glomalin-related soil protein (GRSP) production which supports binding of aggregates, enhanced SOC and biological attributes. However, conservation agricultural practices in agroecosystem may have significant impact on AMF diversity, GRSP and soil quality-related parameters (SQRPs). This current experiment was implemented to gauge AMF conization percentage (AMF-CP), GSRP and significant changes on critical SQRPs, and to investigate the linkages between AMF-CP, GRSP and SQRPs as influenced by synergistic tillage and weed management in CA. Contrasting tillage practices (Main plots) included the T 1 :Conventional tillage with cotton- Conventional tillage with maize-fallow i.e., No Sesbania rostrata (Farmers' practice), T 2 :Conventional tillage with cotton- Zero tillage with maize- Zero tillage with Sesbania rostrata and T 3 : Zero tillage with cotton+Sesbania rostrata residues- Zero tillage with maize+Cotton residues- Zero tillage with Sesbania rostrata+Maize stubbles. Weed management tactics (Sub plots) were W 1 : Chemical weed control, W 2 : Herbicide rotation, W 3 : Integrated weed management and W 4 : Single hand-weeded control. The roots and soil samples were collected at 60 DAS of maize. Analysis of examined parameters was done duly following standard protocols. The observed results indicated that 22.50 % of AMF-CP, 16.50 % of EE-GRSP and 12.08 % of T-GRSP was significantly higher in conservation tillage compared to T 1 (Farmers practice). SQRPs followed similar trend in the case of tillage. Significantly higher SMBC and β-galactosidase (β-GaA) was exhibited by W4 and W3. A highly significant positive correlation of AMF-CP and T-GRSP pool with SOC (r=0.951∗∗ and 0.756∗∗), SMBC (r=0.872∗∗ and r=0.761∗∗), β-GaA (r=0.916∗∗ and r=0.832∗∗) and WSA1-2mm (r=0.888∗∗ and 0.882∗∗), respectively was also observed. Generally, AMF-CP and GRSP, and SQRPs correlated positively and significantly. The following parameters; T-GRSP, SOC, WSA1-2mm, SMBC and β-GaA were selected as potential indicators to gauge the soil quality based on calculated principal component analysis (PCA). In general, the examined parameters in the study are highly supported by zero-till+crop residues, and can be considered indicators for monitoring agroecosystem.

Study on the Characteristics of Residual Film–Soil–Root Stubble Complex in Maize Stubble Fields of the Hexi Corridor and Establishment of a Discrete Element Model

Plastic film mulching is one of the key technologies for improving agricultural productivity in arid and semi-arid regions. However, residual plastic film can severely disrupt the structure of the topsoil in farmland, leading to a decrease in crop yield. The Hexi Corridor, as the largest seed maize production base in the arid regions of Northwest China, is facing an increasingly prominent issue of residual plastic film recovery. This study designed experiments based on the typical maize planting model in the Hexi Corridor. A discrete element simulation model of the residual film–soil–root stubble complex was established using the Bonding-V2 model and API rapid filling technology. The reliability of the simulation model was verified through shear and puncture tests. The study revealed that the soil type in the Hexi Corridor is heavy sandy soil. The differences between the average maximum shear forces in the simulated and actual shear tests for root stubble–soil complexes at depths of 30 mm, 50 mm, and 100 mm were 4.8%, 6.4%, and 6.5%, respectively. Additionally, the differences in the average maximum vertical loading forces in the simulated and actual puncture tests for root stubble–soil complexes at depths of 50 mm and 100 mm were 6.4% and 12.37%, respectively. The small discrepancies between the simulated and actual values, along with the consistency of particle movement trends with real-world conditions, confirmed the reliability and accuracy of the simulation model. This indicates that the established discrete element flexible model can effectively represent actual field conditions, providing discrete element model parameters and theoretical support for optimizing the design of key components in China’s mechanized root stubble handling and residual film recovery machinery.

Long-Term Maize Intercropping with Peanut and Phosphorus Application Maintains Sustainable Farmland Productivity by Improving Soil Aggregate Stability and P Availability

The intercropping of maize (Zea mays L.) and peanuts (Arachis hypogaea L.) (M||P) significantly enhances crop yield. In a long-term M||P field experiment with two P fertilizer levels, we examined how long-term M||P affects topsoil aggregate fractions and stability, organic carbon (SOC), available phosphorus (AP), and total phosphorus (TP) in each aggregate fraction, along with crop yields. Compared to their respective monocultures, long-term M||P substantially increased the proportion of topsoil mechanical macroaggregates (7.6–16.3%) and water-stable macroaggregates (>1 mm) (13.8–36.1%), while reducing the unstable aggregate index (ELT) and the percentage of aggregation destruction (PAD). M||P significantly boosted the concentration (12.9–39.9%) and contribution rate (4.1–47.9%) of SOC in macroaggregates compared to single crops. Moreover, the concentration of TP in macroaggregates (>1 mm) and AP in each aggregate fraction of M||P exceeded that of the respective single crops (p < 0.05). Furthermore, M||P significantly increased the Ca2-P, Ca8-P, Al-P, and Fe-P concentrations of intercropped maize (IM) and the Ca8-P, O-P, and Ca10-P concentrations of intercropped peanuts (IP). The land equivalent ratio (LER) of M||P was higher than one, and M||P stubble improved the yield of subsequent winter wheat (Triticum aestivum L.) compared with sole-crop maize stubble. P application augmented the concentration of SOC, TP, and AP in macroaggregates, resulting in improved crop yields. In conclusion, our findings suggest that long-term M||P combined with P application sustains farmland productivity in the North China Plain by increasing SOC and macroaggregate fractions, improving aggregate stability, and enhancing soil P availability.

Shallow-incorporated straw returning further improves rainfed maize productivity, profitability and soil carbon turnover on the basis of plastic film mulching

Ridge and furrow plastic film mulching (RFM) has improved net primary productivity (NPP) to a high level in semi-arid rainfed agricultural regions. Yet, it is unclear whether there is still a room for further improvement on NPP while stabilizing soil organic carbon through returning previous maize stover pieces. To address this issue, maize stubbles were smashed into pieces and in situ ploughed into 30 cm topsoil at a semi-arid site in northwest China from 2016 to 2017. This was done using the Pioneer 335 maize variety with three treatments (CK, ridge and furrow without mulching; RFM, ridge and furrow with plastic mulching; RFML, 3.49 t ha−1 of maize stover returning in RFM; RFMH, 5.24 t ha−1 of returning in RFM). The results indicated that maize stover returning exhibited similar trend as RFM at early cool seedling stage, raising the topsoil temperature. However, in warm and dry silking stage (2017), both stover returning rates reduced soil temperatures by 1.33 and 0.8 ◦C relative to RFM and CK (P < 0.05), respectively. The soil water storage increased significantly in RFMH by 17.3% and RFML by 28.5% relative to that of RFM, in a warm and dry growing season (2017). Critically, stover returning increased (P < 0.05) soil organic carbon and light fraction organic carbon turnover across the two growing seasons. By improving hydrothermal conditions, stover returning in RFM increased biomass accumulation and grain yield (P < 0.05), leading to higher (P < 0.05) net economic benefit, with greater above-ground biomass NPP (74.5–93.2%) and below-ground biomass NPP (88.5–89.4%), compared with CK. In conclusion, maize stover returning of stover pieces into topsoil might be a promising solution to enhance carbon turnover for higher net primary productivity on the basis of plastic film mulching in semiarid rainfed region.

The Feasibility Synthesis of Growing Hemp Instead of Maize to Reduce Smog from Maize Stubble Burning in Northern Thailand

The Feasibility Synthesis of Growing Hemp Instead of Maize to Reduce Smog from Maize Stubble Burning in Northern Thailand

Maize silage and maize stubble, strategy for cattle feed in dry seasons

The objective was to estimate the production costs and profitability of maize silage and maize stubble as a feeding strategy for cattle in dry seasons in the southern region of Estado de México. Methodology:30 semi-structured surveys with non-probabilistic sampling were applied during the spring/summer 2020 cycle. Socioeconomic variables, the profitability threshold and the benefit/cost ratio were analyzed. The production units were characterized as small, the average age of producers did not exceed 45 years and nine years dedicated to production. Results: The average production of maize silage and maize stubble was 28 and 7.20 tons with a cost of 1,278.40 and 3,587.23 pesos per ton. Conclusions: The benefit/cost ratio in maize silage and stubble was 0.46 and 0.16. The conclusion is that both activities were profitable with a predominance of maize silage.

Effect of in situ soil moisture conservation practices on maize and its crop residue incorporation on yield and economics of succeeding transplanted rice Var. ADT 46

Crop residue incorporation is a key component of sustainable cropping systems. It reduces the adverse effects of residue burning and enhances soil fertility. Effective usage of crop residue in the field and proper management are required. With this background, a field experiment was conducted during 2020 – 21 in the maize-rice cropping sequence at Annamalai University Experimental Farm, Department of Agronomy, Faculty of Agriculture, Annamalai University, Annamalai Nagar, Tamil Nadu to find out the residual effect of different mulching practices adopted in preceding maize crop and maize stubble incorporation on the growth, yield and economics of transplanted rice Var. ADT 46. The field experiment was conducted in Factorial Randomized Block Design with three replications. In factor I, soil moisture conservation in preceding maize crop viz., mulching of sugarcane trash, water hyacinth, hydrogel and control were allotted. In factor II, different levels of maize crop stubble incorporation on rice viz., 0, 33, 66 and 100% were provided. Water hyacinth mulched plot (M3) to the preceding crop registered significantly (þ &lt;0.05) higher yield parameters, yield and economic returns of succeeding rice. The lower values were observed in unmulched (M1) plot. With respect to maize crop stubble incorporation on rice crop, the incorporation of 66% (SI3) of maize stubble registered higher yield parameters, yield and economic returns. In the interaction effects, mulching with water hyacinth to preceding maize + maize crop stubble incorporation at 66% in rice crop (M3SI3) recorded significantly (þ &lt;0.05) higher yield parameters, yield and economic returns than other treatments. The lowest values were recorded with an unmulched + 100% crop residue incorporated (M1SI4) plot. Mulching the preceding maize crop with water hyacinth at a rate of 12 t ha-1 and incorporating 66% maize stubble into the transplanted rice (M3SI3) had a remarkable yield advantage and financial rewards.

Calibration of Discrete Element Parameters of Maize Root and Its Mixture with Soil

Discrete element simulation is an effective method to reveal the interaction between tillage components and work objects. However, due to the lack of discrete element modelling parameters of maize root and its mixture with soil, existing tillage models cannot accurately simulate the farmland environment under a no-tillage system. This study developed single maize root (SMR) with different diameters and maize root-soil mixture (MRSM) DEM models based on calibrated parameters through the angle of repose (AOR) tests. First, the Plackett–Burman and the steepest climb tests were performed to identify the range of essential parameters for the AOR of the SMR. Then, the optimal parameters for the SMR and MRSR models were obtained by Box–Behnken design (BBD) testing. The results showed that the static friction coefficient of SMR-SMR and the rolling friction coefficient of SMR-SMR and SMR-steel significantly affected the AOR. In addition, the AOR of MRSM was extremely sensitive to the restitution coefficient and surface energy coefficient of root soil. Based on optimal parameters, the relative errors between the simulated and measured AOR and pixel peak values of the piles’ contour curve were less than 5% for SMR and MRSM. The error of the dynamic AOR of the measured and simulated MSRM was less than 10%. These results indicate that the parameter calibration method and the developed models can be valuable references for DEM simulation for maize stubble and tillage.

Influence of Maturation Time on Organic Matter Loss and Quality of Maize Stubble Compost

Stubble management is one of the major challenges in maize cultivation, which has seen a surge in recent years. Using maize straw exclusively for composting is problematic due to its elevated C/N ratio and significant lignin content, both of which decelerate the composting process. Ripe farm manure, molasses, and urea fertilizer were added to finely ground maize straw to accelerate composting. Compost samples were collected on the 15th, 30th, 45th, and 60th days for analyses of parameters such as organic carbon, total nitrogen (TN), C/N ratio, ammonium and nitrate nitrogen, pH, EC, organic matter (OM), OM loss (OML), and macro and microelements. The C/N ratio of the compost mixture, which began at a 30:1 ratio, reduced to 27.99, 22.88, 16.85, and 12.89 on the 15th, 30th, 45th, and 60th days of composting, respectively. Concurrently, the TN content in the compost mixture rose from 1.29% on day 15 to 2.34% on day 60. OML registered at 30.50% and 48.57% on the 45th and 60th days, respectively. The results indicate that the composting process can be deemed complete by the 45th day, as the rising compost temperature leads to the inactivation of potential pathogens and weed seeds in the environment.

Positive effects of maize incorporation into the traditional tobacco cropping systems on soil nutrients, microbial biomass, enzyme activities, and bacterial compositions

ABSTRACT To reduce tobacco production suggested by the Chinese government, a 12-year field experiment was established by planting other crops in a traditional tobacco growing system every 2 years. Thus, tobacco-wheat, tobacco-canola, tobacco-wheat-maize, and tobacco-canola-maize rotations were implemented to compare the changes in soil properties. Compared to the initial soil, available N, P, and K increased or changed little after 12-year cropping except for decreased available N in the tobacco-wheat rotation soil. Compared with two-crop rotations, soil organic matter, available N, microbial biomass, enzyme activities (urease, phosphatase, and dehydrogenase), and bacterial community indexes (16S rDNA sequences, operational taxonomic units (OTUs), and richness and diversity indexes) increased in the three-crop rotations. The return of voluminous maize stubble should be the important reason for the change of these soil properties. All cropping soils were dominated by five bacteria (Proteobacteria, Acidobacteria, Firmicutes, Actinobacteria, and Bacteroidetes) accounting for 53.5–62.3% of the 16S rDNA sequences. Among the top 20 predominant bacteria, 10 were commonly found in all soils and only 2–5 were unique. Therefore, maize incorporation into the traditional two-crop systems increased stubble return and improved soil properties. However, bacterial community composition was more influenced by the soil itself than cropping systems.

Detection and Factors That Induce Stenocarpella spp. Survival in Maize Stubble and Soil Suppressiveness under Tropical Conditions

Stenocarpella spp. causes stalk and ear rot in maize and overwinters in stubble during the off-season. Understanding the factors that guide saprophytic colonization is a crucial strategy for management. In this study, we analyzed the abiotic factors and crop management practices in relation to the inoculum of Stenocarpella spp. in stubble by qPCR. Soil samples were used for suppressiveness tests against Fusarium verticillioides, Fusarium graminearum, and Stenocarpella maydis. In the 29 fields, different levels of Stenocarpella spp. were detected. Only three fields were considered suppressive for the three pathogens. Heat maps showed that soil suppressiveness was inversely related to the pathogen concentration, and the suppressiveness of one pathogen was correlated with the suppressiveness of other pathogens. Under no-tillage systems in which rotation with soybeans was adopted, Stenocarpella spp. were detected at lower concentrations than in areas that adopted no-tillage systems with maize monocultures. While in tillage systems, the maize–maize monocropping increases the inoculum level of Stenocarpella spp. Crop rotation is a factor related to the observed reduction in the pathogen concentration and increases in the broad-spectrum antagonistic microbial communities. These communities guide the suppressiveness of soil-borne diseases in maize fields cultivated under tropical conditions.

Effects of temperature and soil fauna on the reduction and leaching of deoxynivalenol and zearalenone from Fusarium graminearum-infected maize stubbles

A microcosm study was conducted at two different temperatures under laboratory conditions to investigate the regulatory capacity and the interactive performance of two soil fauna species (Aporrectodea caliginosa, earthworms, and Proisotoma minuta, collembolans) on the reduction of Fusarium toxins in contaminated maize stubbles. Single and mixed species treatments were exposed to artificially infected maize stubbles highly contaminated with the mycotoxins deoxynivalenol (DON) (10,462 µg kg−1) and zearalenone (ZEN) (2,780 µg kg−1) at 17 °C and 25 °C for time periods of 3 and 6 weeks. Immediately after the respective end of incubation, the microcosms were heavily watered to determine the leaching potential of DON and ZEN from contaminated maize stubbles. Maize residues, soil, and eluted water (percolate) samples were analysed for mycotoxin content using liquid chromatography coupled to mass spectrometry. The biomass of introduced earthworms and number of collembolans were monitored to get information about their adaptability to the experimental conditions. While the decline of ZEN was temperature-dependent, but not influenced by faunal activities, a reduction of DON due to faunal impact was observed by trend. In the leaching experiment, 67–82% of the DON content in the residual maize stubbles leached from the plant material by irrigation and was detected in the soil (1.9–3.4 µg kg−1) and in the percolate (12–295 µg L−1). In the case of ZEN, 27–50% of the mycotoxin leached from the residual maize stubbles due to watering but was only occasionally detected in traces in the soil and not found in the percolate. The results clearly reveal a leaching potential of both DON and ZEN, respectively, but a mobilisation with water was only observed for DON. Temperature confirmed to be a key factor, affecting the fate of the mycotoxins in the soil by driving the interaction between different soil fauna members as well as functional and trophic levels within the soil food web.

Characterization and evaluation of Flammulina mexicana growth in lignocellulosic residues

Flammulina mexicana is a fungus species endemic to high mountains and has potential for commercial cultivation. Four strains were isolated from wild fruit bodies and its growth was evaluated in two culture media. There were no morphological differences among these strains; however, the choice of culture media did produce differences. Growth rate was superior in strains IE 974 and IE 986 at 0.65 cm day-1. These strains also presented the highest biomass production at 6.9 and 7.7 g L-1, respectively; with a period of 35 days in production with solid spawn and 20 days with liquid spawn. All the four strains have the ability to fructify in agricultural and forestry wastes. Strains IE 986 and IE 974 presented better biological efficiency at 34.5 % and 31.9 %, respectively, with maize stubble as a substrate. A nutritional analysis of the fructifications obtained showed a high percentage of fiber (52.51 %) and low carbohydrate content (9.03 %). For this reason, culture of these species represents an alternative for their ex situ conservation and use.

Surveillance and habitat diversity affect European brown hare (Lepus europaeus) density in protected breeding areas

The European brown hare (Lepus europaeus) is an important game species throughout Europe. In Italy, for preventing the introduction of allochthonous strains, the management of brown hare populations has focused on the establishment of small protected areas (ZRCs), appositely managed for disposing of wild-born hares for restocking hunting territories. We investigated the effects of both land cover and surveillance on hare density and habitat preferences in 20 ZRCs, monitored twice per year (pre- and post-breeding periods) between 1997 and 2017. Density, as assessed by spotlight counts, ranged between 2.8 and 47.0 ind/km2 in spring and 5.0 and 68.4 ind/km2 in autumn. Surveillance, percent length of protected boundaries, year of institution and habitat diversity, as assessed by Shannon’s Index, were the main factors affecting hare density. During their foraging activity, hares selected ryegrass, hayfields and lucerne, while avoided maize stubble and ploughed fields and were never recorded in poplar plantations or next to human settlements. While the effects of habitat heterogeneity on hare density have been widely studied, we suggest that the involvement of local stakeholders may be of paramount importance for ensuring effective conservation measures.

Cinética de degradación ruminal in situ de ensilado de rastrojo de maíz (Zea mays) con niveles crecientes de urea

Se estudió el efecto de la inclusión de urea sobre la composición y cinética de degradación ruminal in situ en el ensilado de rastrojo de maíz. Se partió de cuatro de tratamientos al adicionar el 0, 1, 2 y 3% de urea a una mezcla de rastrojo de maíz con el 10% de melaza. Se elaboraron 128 microsilos (3 kg/unidad y 4 repeticiones por tratamiento). La apertura de los silos se realizó a los 7, 14, 21, 28, 35, 42, 49 y 56 días. Se determinó el contenido de la materia seca (MS), materia orgánica (MO), proteína bruta (PB), FND y FAD. La degradabilidad in situ se obtuvo mediante el método de Mehrez y Orskov y la degradabilidad de MS y PB mediante el análisis de los residuos con el método Kjeldhal. Los datos se analizaron con el procedimiento GLM y el test de Tukey (P±

Producción y calidad de grano y rastrojo en maíces en el altiplano poblano

La mayoría de las unidades de producción de rumiantes en los valles altos, en diversas regiones de México, integran al maíz como fuente de forraje. Este cultivo debe ser, por tanto, alto productor de grano y rastrojo de calidad. Con base en esto, el objetivo de la presente investigación fue evaluar el comportamiento de 36 genotipos de maíz en el altiplano de Puebla durante el año 2017. Los genotipos fueron siete híbridos comerciales, una variedad sintética, nueve poblaciones de polinización libre y diecinueve híbridos experimentales de cruza simple derivados de variedades locales. La siembra se realizó en tres experimentos con diseño látice 6x6 en unidades experimentales de dos surcos de 80 cm de ancho por cinco metros de largo. Se evaluaron variables relacionadas con características propias de las plantas y químicas del rastrojo producido. La principal variable discriminatoria fue rendimiento útil (RUT) que incluyó el rendimiento de grano (RGR) con la producción y digestibilidad del rastrojo. Los genotipos fueron diferentes (p&lt; 0.001) en todas las variables medidas. En RUT, los genotipos sobresalientes fueron: HS-2®, Águila 215W®, SM-16 60x66, SM-16 5x64, SM-16 64x66, SM-16 53x64, SM-16 13x44, SM-16 23x60, SM-16 58x21, SM-16 44x64, SM-16 136x142, Niebla® y SM-16 21x64. No obstante, esta variable logra enmascarar genotipos que tienen producciones altas de grano y rastrojo, pero que tienen baja digestibilidad. Sólo el SM-16 5x64 tuvo superioridad en digestibilidad, pero rendimiento medio de materia seca de rastrojo, lo cual le da mayor potencial para ser un genotipo de doble propósito

Casos inusuales de colibacilosis septicémica en terneros neonatos de cría para carne

&lt;p&gt;La colibacilosis septicémica es causada por Escherichia coli y suele afectar a terneros de tambo. El objetivo de este trabajo fue describir casos de colibacilosis en terneros de cría para carne. Las terneras afectadas (casos A y B) tenían 4 y 3 días de vida, eran hijas de vaquillonas y nacieron por parto distócico. El rodeo estaba en un rastrojo de maíz y en una pastura polifítica con escasa cobertura vegetal del suelo, debido al anegamiento por las intensas lluvias. Los signos clínicos y lesiones fueron similares en ambos casos e incluyeron decaimiento, hipopión, dificultad para desplazarse, deshidratación, disnea, poliartritis e hiperemia de vasos esclerales. Ambos animales desarrollaron leucocitosis y neutrofilia, con formas inmaduras en el caso A, en el cual se aisló E. coli de fluidos corporales, hígado, bazo y pulmón, recolectados a la necropsia, observándose aumento del volumen de líquido sinovial, con presencia de coágulos de fibrina. En el caso B se aisló E. coli a partir de sangre entera. Los aislamientos efectuados en diferentes órganos (caso A) y sangre (caso B) fueron sensibles a gentamicina, ciprofloxacina y minociclina. La ternera del caso B respondió favorablemente al tratamiento, durante 3 días, con gentamicina, enrofloxacina, meglumina de flunixin y sales rehidratantes orales. No se volvieron a observar casos similares durante la parición. Esta enfermedad debería considerarse en el diagnóstico diferencial de mortalidad neonatal en terneros de rodeos para carne, fundamentalmente cuando ocurren los factores predisponentes mencionados.&lt;/p&gt;

Pontoscolex corethrurus: A homeless invasive tropical earthworm?

The presence of earthworm species in crop fields is as old as agriculture itself. The earthworms Pontoscolex corethrurus (invasive) and Balanteodrilus pearsei (native) are associated with the emergence of agriculture and sedentism in the region Amazon and Maya, respectively. Both species have shifted their preference from their natural habitat to the cropland niche. They contrast in terms of intensification of agricultural land use (anthropic impact to the symbiotic soil microbiome). P. corethrurus inhabits conventional agroecosystems, while B. pearsei thrives in traditional agroecosystems, i.e., P. corethrurus has not yet been recorded in soils where B. pearsei dwells. The demographic behavior of these two earthworm species was assessed in the laboratory over 100 days, according to their origin (OE; P. corethrurus and B. pearsei) food quality (FQ; soil only, maize stubble, Mucuna pruriens), and soil moisture (SM; 25, 33, 42%). The results showed that OE, FQ, SM, and the OE x FQ interaction were highly significant for the survival, growth, and reproduction of earthworms. P. corethrurus showed a lower survival rate (> mortality). P. corethrurus survivors fed a diet of low-to-intermediate nutritional quality (soil and stubble maize, respectively) showed a greater capacity to grow and reproduce; however, it was surpassed by the native earthworm when fed a high-quality diet (M. pruriens). Besides, P. corethrurus displayed a low cocoon hatching (emergence of juveniles). These results suggest that the presence of the invasive species was associated with a negative interaction with the soil microbiota where the native species dwells, and with the absence of natural mutualistic bacteria (gut, nephridia, and cocoons). These results are consistent with the absence of P. corethrurus in milpa and pasture-type agricultural niches managed by peasants (agroecologists) to grow food regularly through biological soil management. Results reported here suggest that P. corethrurus is an invasive species that is neither wild nor domesticated, that is, its eco-evolutionary phylogeny needs to be derived based on its symbionts.

Сontrolled breeding of the psychrophilic strain G-034 VIZR of Trichoderma asperellum for fast crop residues’ polymers utilization and soil enhancement

Genus Trichoderma strains as the natural plant residues’ biodestructors, highly active antagonists of soil phytopathogens and phytoregulators with the widest range of optimum conditions for their development, are widely used in biologics development. Of particular importance in Russia’s northern regions, especially in winter crop cultivation, is the ability of a microorganism’s strain used in agro-technologies to maintain viability and target biological activity at low temperatures. In this connection, this work purpose is to select a psychrotolerant strain of T. asperellum for the rapid crop residues’ polymer utilization and soil enhancement at low temperature, as well as to evaluate its activity under laboratory and field conditions. In the work process, the following tasks were addressed: selecting psychrotolerant strains of T. asperellum with high cellulolytic activity; further controlled breeding of psychrophilic strains capable of rapid growth, active colonization of plant substrates and high sporulation at 4–8 °C; evaluating the target activity of the selected psychrophilic strain as a cellulolytic as well as antagonistic activity against cereal pathogens; obtaining laboratory samples of bioformulations by deep-surface cultivation on non-sterile peat and multirecycled wastes from the edible mushrooms production and assessing their efficacy in field small-plot trials. The methods for inoculum cultivation, sporulation capacity determination, modified wet chamber, estimating antagonistic activity and biologics’ quality, field small-plot trials management, quantitative estimates of biomass losses, cellulose and lignin content were used in the work. The active psychrophilic strain for the rapid crop residues’ polymer utilization and soil enhancement controlled breeding was selected during a four-step screening of 29 T. asperellum strains from All-Russian Research Institute of Plant Protection (VIZR) State Microorganisms’ Collection with high cellulolytic and antagonistic activities. In terms of linear growth rate, antagonistic and hyperparasitic activities at 4–8 °С, a high rate of wheat and maize stubble residues’ colonization, a perspective psychrophilic strain G-034 of T. asperellum was selected for developing the laboratory samples of biologics and for running field trials. In small-plot trials, the active maize crop residues’ decomposition under the T. asperellum G-034 influence was revealed, resulting in the complete loss of plant intact state in 12 months due to more than 80 % cellulose and 20 % lignin biodestruction. The maximum loss of maize crop residues biomass for 12 months was more than 70 %. The T. asperellum strain G-034 was active after field hibernation in an amount of ×104 cfu/g, resulting in a titer increase with seasonal temperature rising and the trophic base bioavailability growth.

Colonización miceliar de Flammulina mexicana a partir de inóculo sólido y líquido en residuos agroforestales

La producción de inóculo es un proceso que requiere de su optimización, ya que, en gran parte depende generar una mayor eficiencia biológica en el cultivo de hongos, reducir los costos económicos, así como problemas de contaminación y tiempo en los ciclos de cultivo. En la presente investigación, durante el año 2016, se evaluó la colonización de cuatro sustratos (rastrojo de maíz, aserrín de Quercus sp., aserrín de Senecio cinerarioides y rastrojo de maíz en combinación con aserrín de S. cinerarioides) con inóculo líquido y sólido de F. mexicana (cepas IE 974, IE 984, IE 985, IE 986). Como resultados se obtuvo que la velocidad de colonización de los diferentes sustratos varió entre las cuatro cepas (p≤ 0.0001). Los sustratos con inóculo sólido presentaron velocidades de crecimiento menores respecto al inóculo líquido, los sustratos con inóculo líquido fueron colonizados en un periodo de 17 días y con inóculo sólido tardaron 50 días y en algunos casos hubo partes que no fueron colonizadas; lo cual también estuvo relacionado con el sustrato utilizado, presentando una interacción (p≤ 0.0001) entre el tipo de inóculo y el sustrato que afecta la velocidad de crecimiento. La incorporación de inóculo líquido en el cultivo de hongos permite aumentar la densidad y velocidad de crecimiento miceliar, así como la aparición temprana de primordios, lo que contribuye a reducir el tiempo en el ciclo de cultivo. &#x0D;