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Trichoderma is a genus of widespread filamentous fungi widely used in agriculture as biofungicides for controlling a wide range of plant diseases. Trichoderma, as is well known, can not only effectively control crop diseases but also improve soil physico-chemical properties and increase soil productivity. However, the effects of its control on crop growth and the soil's ecological environment are unclear. The results of Trichoderma on disease resistance, yield, and crop growth as well as the effects of Trichoderma on the soil ecological environment from the standpoint of soil physical, chemical, and microbial properties were therefore reported in this study. Furthermore, this paper highlighted the shortcomings of the existing research on the impact of Trichoderma on crop and soil properties and emphasised opportunities to address the gaps in the existing research on the effects of Trichoderma on crops and soil attributes. This review will provide a theoretical foundation for further research and application of Trichoderma in agricultural production. [ABSTRACT FROM AUTHOR]

This experiment was carried out during 2019 at Department of Soil Science, University of Sargodha, Pakistan to judge the toxic effect of sodium bicarbonate (NaHCO3) commonly recognized as sodicity on soil chemical characteristics using rice as test crop. There were seven treatments with three replicates applied using completely randomized design (CRD). Various levels of sodicity were developed artificially including 15, 20, 25, 30, 35 and 40 SAR by using sodium bicarbonate (NaHCO3). Sufficient time was given for development of desired level of sodicity. Rice was used as test crop. Practices like irrigation, hoeing and weeds eradication were done as per crop requirement. Recommended doses of chemical fertilizer was applied. Crop was raised for 120 days and then collection of soil and plants samples were carried out from all pots for analysis of sodium (Na) and potassium (K) ion concentrations. Similarly, pH, EC and SAR were also determined from all soil samples. Results revealed that deterioration of soil properties (pH, EC and SAR) occurred by the addition of NaHCO3 as values of these properties were negatively affected by increased levels of sodicity. Numerical values of soil pH raised from 7.78 to 9.35, EC from 1.85 to 6.13 dS/m, SAR from 9.80 to 41.53 and ESP from 11.64 to 37.49 me/ L respectively. Regarding ionic composition of rice, an increase in Na ion and decrease in K ion concentration was observed in all treatments in comparison with control. Potassium content in rice decreased from 2.3 to 1.2% while sodium concentration was raised from 102.26 to 410.14 me/L. Toxic effect of sodicity on soil pH, EC, SAR and ESP as well as Na/K ratio in rice plants were enhanced with increasing levels of NaHCO3. [ABSTRACT FROM AUTHOR]

Herbaceous vegetation is of great ecological importance and responds quickly to environmental changes. The present study was aimed to understand the variation in herbaceous species composition, biomass and soil physico-chemical properties in the naturally formed gap and the understory of semi-arid forests in the Aravalli hills. Four permanent plots consisting of the gap as well as the understory were established. To study herbs phytosociological attributes and biomass, 10 quadrats of 0.5 × 0.5 m size were laid in each plot. For soil physico-chemical properties, 5 soil samples were collected randomly at 0–10 cm depth from each plot. Relationships among biodiversity indices, herbaceous biomass and soil physico-chemical properties were determined using Redundancy Analysis (RDA) and correlation analysis. Across the sites, Poaceae was the dominant family. All species showed a contagious distribution pattern. In the understory, Importance Value Index (IVI) was the recorded highest for Oplismenus burmannii, ranging from 138 to 230.5 while in the gap, it was the highest for Achyranthes aspera (56.15) followed by Eragrostis ciliaris (53.1). Both sites included, herbaceous community biomass in the gap ranging from 700 to 900 g m−2 while in the understory it ranged from 30 to 70 g m−2. Cenchrus ciliaris (597.97 g m−2) and Chrysopogon sp. (391.2 g m−2) contributed a major proportion of herbaceous community biomass in the gap. Oplismenus burmannii (52.2 g m−2), Dipteracanthus prostratus (16.6 g m−2) and Cynodon dactylon (9.6 g m−2) contributed a major proportion of herbaceous community biomass in the understory. The understory soil had significantly (p < 0.05) higher soil moisture (%), electrical conductivity (EC), soil organic carbon (SOC) and soil total nitrogen (TN) compared to the gap. Even though canopy had positive effects on soil physico-chemical properties, it has negatively influenced herbaceous species composition, diversity and biomass, due to significant reduction in solar radiation reaching the ground. [ABSTRACT FROM AUTHOR]

Field experiment was conducted in the 2019 and 2020 early cropping seasons at the University of Calabar Teaching and Research Farm, Calabar, to assess the foliage yield of fluted pumpkin (Telfairia occidentalis Hook F.) as affected by organic manure and cutting frequency on soil of Calabar. The experiment was a factorial combination of four poultry manure rates (0, 3, 6 and 9 tonnes per hectare) and three cutting frequency (2, 3 and 4 weekly intervals), laid out in randomized complete block design (RCBD) with three replications. Data were collected on vine length, number of leaves, internode length, fresh leaves, dry matter weights and soil physico-chemical properties, and analyzed. Significant means were compared using Fisher's Least Significant Difference (FLSD) at 5 % probability. Results indicated that the sand proportions decreased after harvest while the silt and clay proportions, the soil pH, total nitrogen, organic carbon, organic matter, potassium, magnesium, effective cation exchange capacity (ECEC) and base saturation all increased after harvest in both cropping years. There were significant (p <.0. 05) effects of PM, cutting frequency and their interactions on vine length, number of leaves, internode length, fresh leaves and leaves dry matter weights in both years of study. Plots treated with 9 t/ha of PM produced the longest vines, higher number of leaves, heavier fresh leaf and leaf dry matter. This was followed by plots treated with 6 t/ha of PM while the lowest was the plot with zero PM treatment. Foliage harvest at 3-weekly cut intervals produced the highest cumulative number of leaves, fresh leaf and leaf dry matter weights, followed by the 4-weekly cut intervals while the lowest was the 2-weekly cut intervals. The interaction of 9 t/ha PM with 3-weekly cut intervals produced the best effect and is therefore recommended. [ABSTRACT FROM AUTHOR]

The present investigation was conducted at the Research Farm, Khalsa College, Amritsar during rabi season of 2017-18 in order to evaluate the impact of organic manures (FYM, Vermicompost, Poultry manure) and inorganic fertilizers on soil physico-chemical properties and available nutrient status in soil after onion (Allium cepa L.) harvest. The experiment was laid out in randomized block design with twelve treatments and replicated thrice. It was observed that significant variation in organic carbon, bulk density, available macro (N, P, K and S) and micro (Fe, Mn, Zn and Cu) nutrients status was noticed when organic manures were integrated with inorganic fertilizers as compared to sole use of inorganic fertilizers and initial status of soil. The maximum available nutrient status was recorded with treatment T12 {25% RDNF + 25% N (FYM) + 25% N (VC) + 25% N (PM)} whereas lowest was recorded with treatment T1 (control). The soil properties such as pH, EC, particle density and porosity did not showed any significant difference. [ABSTRACT FROM AUTHOR]

The present study was undertaken to assess the status of available copper (Cu) in the intensively rice growing soils of Madurai district, Tamil Nadu. A total of 235 geo referenced surface soil samples were collected and analysed for plant available Cu and simple correlation was worked out to ascertain the degree of relationship between soil properties and available Cu content of soils of the study area. Plant available Cu in the entire rice growing soils ranged from 0.08 to 9.50 mg kg-1. Out of two hundred and thirty five locations of rice growing soils of Madurai district collected for the purpose of delineation of copper, 29.78 per cent of the soils were deficient in Cu status while 31.91 and 38.29 per cent areas were medium and high in available Cu. Among the soil properties, clay, silt and CEC had a positive influence on the availability of Cu whereas, sand, pH, OC and CaCO3 content had negative influence on available copper. The step-wise multiple regression equation in general indicated that the pH, CEC, OC and sand accounted for 54.50 per cent variation in available Cu in the soils of study area. [ABSTRACT FROM AUTHOR]

Cultivation of legume plants is well known to improve soil N level and net primary productivity; besides, it may deliver other ecosystem benefits such as increasing soil carbon sequestration and soil food web complexity. However, little is known about whether legumes can improve the resistance of soils to ecosystem disturbances. In the present study, we compared the resistance of soils to an ecosystem disturbance (understory removal) in the presence or absence of a legume species (Cassia alata) in mixed tree species plantations in southern China. Soil physico-chemical and biotic properties were employed to quantify the resistance of soils to understory removal. Our results showed that the resistance indices of soil water content, omnivorous-predacious nematode abundance and nematode channel index to understory removal were greater in the presence of legumes than those without legumes in wet season. The resistance indices of fungal to bacterial ratio, fungivorous nematode abundance and total arthropod abundance were greater in the presence of legume than those without legume species in dry season. Our results indicate that legumes may enhance the resistances of soil physico-chemical and biological properties to the ecosystem disturbance. Our findings could provide a better understanding of the myriad ways in which legumes can positively affect ecosystem functioning. [ABSTRACT FROM AUTHOR]

This study was undertaken to develop new pedotransfer functions (PTFs) for the estimation of soil moisture content at field capacity (FC, at −33 kPa) and permanent wilting point (PWP, at −1500 kPa) for South African soils based on easily measurable soil physico-chemical properties. The new PTFs were developed using stepwise multiple linear regressions with the dependent variable (either FC or PWP) against clay, silt, sand and soil organic carbon (SOC) content from a total of 3171 soil horizons as the explanatory variables. These new PTFs were evaluated and compared with five well-established PTFs using a total of 3136 soil horizons as an independent dataset. The coefficient of determination (r2) values for the existing PTFs ranged from 0.65–0.72 for FC and 0.72–0.81 for PWP, whilst those developed in this study were 0.77 and 0.82 for FC and PWP, respectively. The root mean square error (RMSE) values for the well-established PTFs ranged from 0.052–0.058 kg kg−1 for FC and 0.030–0.036 kg kg−1 for PWP, whilst those developed in this study were 0.047 and 0.029 kg kg−1 for FC and PWP, respectively. These findings suggest that PTFs derived locally using a large number of soil horizons acquired from different agro-climatic locations improved the estimation of soil moisture at FC and PWP. Due to the range of conditions and large soil datasets used in this study, it is concluded that these new PTFs can be applied with caution in other regions facing data scarcity but with similar soil types and climatic conditions. [ABSTRACT FROM AUTHOR]

Polychlorinated biphenyls (PCBs) belong to the organic pollutants that are toxic to humans and harmful to environments. Numerous studies dealing with the impact of PCBs on soil microorganisms have focused on bacterial communities. The effects of PCBs on fungal communities in three different PCB-polluted soils from former industrial sites were investigated using high-throughput sequencing of the internal transcribed spacer 1 region. Significant differences in fungal alpha diversity were observed mainly due to soil physico-chemical properties. PCBs only influenced the richness of the fungal communities by increasing it. Fungal composition was rather strongly influenced by both PCBs and soil properties, resulting in different communities associated with each soil. Sixteen Ascomycota species were present in all three soils, including Stachybotrys chartarum, Fusarium oxysporum, Penicillium canescens, Penicillium chrysogenum,Penicillium citrosulfuratum and Penicillium brevicompactum, which are usually found in PCB-polluted soils, and Fusarium solani, Penicillium canescens, Penicillium citrosulfuratum and Penicillium chrysogenum, which are known PCB degraders. This study demonstrated that PCBs influence the richness and the composition of fungal communities. Their influence, associated with that of soil physico-chemical properties, led to distinct fungal communities, but with sixteen species common to the three soils which could be considered as ubiquitous species in PCB-polluted soils. [ABSTRACT FROM AUTHOR]