Soil Biological Characteristics Research Articles

Ungulates alter plant cover without consistent effect on soil ecosystem functioning

Shifts in animal husbandry and landscape use have significantly changed ungulate grazing effects on ecosystem functioning. These changes are now the subject of extensive research with respect to plant and soil communities, but the results of these studies are highly varied and context dependent. The objective of this study is to address contextual variation by holding all sampling methods and analytical approaches constant and analyse the effect of the feral goat (Capra hircus) population of Mallorca Island, Spain, on soil physical, chemical and biological characteristics across five controlled sites. Specifically, vegetation cover and soil properties in fenced plots excluded from ungulates were compared with adjacent grazed plots in five independent mountain areas of Mallorca. Soil microbial activity measured as Community-Level Physiological Profiles (CLPP) using EcoPlate™ increased when ungulates were excluded. However, all other physical and chemical measures of the soils did not vary significantly when we considered ungulate exclusion across all plots, and this may be caused by a soil community that is simply robust to the effects of the herbivores. Or, it may be due to the high heterogeneity that was detected among pair plots comparisons within each of the five sites. Indeed, we find more variability within a site than among our independent sites leading us to hypothesize that grazing does influence biogeochemical cycles, but it does it by increasing variability of the system in general. Our well-controlled multilevel meta-analysis confirms the notion that ungulate effects are highly context dependent, and soil heterogeneity makes resolving clear patterns very challenging. Apparently, context persistently drives the soil response more than the grazing itself, and this is seen even at very small scales.

Use of Crop Rotations, Cover Crops and Green Manures for Disease Suppression in Potato Cropping Systems

Crop rotations and the inclusion of cover crops and green manures are primary tools in the sustainable management of soil-borne diseases in crop production systems. Crop rotations can reduce soil-borne disease through three general mechanisms: (1) serving as a break in the host-pathogen cycle; (2) by altering the soil physical, chemical, or biological characteristics to stimulate microbial activity and diversity; or (3) directly inhibiting pathogens through the release of suppressive or toxic compounds or the enhancement of specific antagonists. Brassicas, sudangrass, and related plant types are disease-suppressive crops well-known for their biofumigation potential but also have other effects on soil microbiology that are important in disease suppression. The efficacy of rotations for reducing soil-borne diseases is dependent on several factors, including crop type, rotation length, rotation sequence, and use of the crop (as full-season rotation, cover crop, or green manure). Years of field research with Brassica and non-Brassica rotation crops in potato cropping systems in Maine have documented the efficacy of Brassica green manures for the reduction of multiple soil-borne diseases. However, they have also indicated that these crops can provide disease control even when not incorporated as green manures and that other non-biofumigant crops (such as barley, ryegrass, and buckwheat) can also be effective in disease suppression. In general, all crops provided better disease control when used as green manure vs. as a cover crop, but the addition of a cover crop can improve control provided by most rotation crops. In long-term cropping system trials, rotations incorporating multiple soil health management practices, such as longer rotations, disease-suppressive rotation crops, cover crops, and green manures, and/or organic amendments have resulted in greater yield and microbial activity and fewer disease problems than standard rotations. These results indicate that improved cropping systems may enhance productivity, sustainability, and economic viability.

Distribution of Soil Extracellular Enzymatic, Microbial, and Biological Functions in the C and N-Cycle Pathways Along a Forest Altitudinal Gradient.

The diverse chemical, biological, and microbial properties of litter and organic matter (OM) in forest soil along an altitudinal gradient are potentially important for nutrient cycling. In the present study, we sought to evaluate soil chemical, biological, microbial, and enzymatic characteristics at four altitude levels (0, 500, 1,000, and 1,500 m) in northern Iran to characterize nutrient cycling in forest soils. The results showed that carbon (C) and nitrogen (N) turnover changed with altitude along with microbial properties and enzyme activity. At the lowest altitude with mixed forest and no beech trees, the higher content of N in litter and soil, higher pH and microbial biomass nitrogen (MBN), and the greater activities of aminopeptidases affected soil N cycling. At elevations above 1,000 m, where beech is the dominant tree species, the higher activities of cellobiohydrolase, arylsulfatase, β-xylosidase, β-galactosidase, endoglucanase, endoxylanase, and manganese peroxidase (MnP) coincided with higher basal respiration (BR), substrate-induced respiration (SIR), and microbial biomass carbon (MBC) and thus favored conditions for microbial entropy and C turnover. The low N content and high C/N ratio at 500-m altitude were associated with the lowest microbial and enzyme activities. Our results support the view that the plain forest with mixed trees (without beech) had higher litter quality and soil fertility, while forest dominated by beech trees had the potential to store higher C and can potentially better mitigate global warming.

Long-term located fertilization causes the differences in root traits, rhizosphere soil biological characteristics and crop yield

ABSTRACT To clarify the changes of root traits, soil biological characteristics and yield after applying fertilizers for 39 years, a long-term located fertilization experiment (1981-) was conducted. Compared to NPK (inorganic fertilizer) and M (organic fertilizer), 0.8NPKM (80% of NPK plus 80% of M) and 0.5NPKM (50% of NPK plus 50% of M) obviously improved root traits. The number of bacteria, fungi, actinomycetes in 0.8NPKM and 0.5NPKM were significantly higher than that in NPK, M and CT (no fertilizer). Compared to NPK, M increased soil microbial quantity. Soil microbial biomass carbon and nitrogen, organic carbon and total N in M were higher than that in NPK. The activities of phosphatase, dehydrogenase and urease in M were significantly higher than that in NPK. Compared to NPK and M, 0.8NPKM and 0.5NPKM enhanced above-mentioned soil enzymes activities. The differences in wheat and maize yields between 0.5NPKM and 0.8NPKM were insignificant, and the harvest index in 0.5NPKM was the highest. Soil microbial quantity, microbial biomass carbon and nitrogen were positively correlated with enzymes activities and root traits. Thus, appropriate combined application amount of organic and inorganic fertilizer might be an effective way to improve root traits, rhizosphere soil micro-biological environment and crop yield.AbbreviationsCT No fertilizer addedNPK Inorganic fertilizer onlyM Organic fertilizer only0.5NPKM Organic fertilizer plus inorganic fertilizer (50% of NPK plus 50% of M)0.8NPKM High application ratio of inorganic and organic fertilizers (80% of NPK plus 80% of M)

Comparison of Soil Biological Properties and Bacterial Diversity in Sugarcane, Soybean, Mung Bean and Peanut Intercropping Systems

Sugarcane intercropping with soybean [Glycine max (Linn.) Merr.], mung bean [Vigna radiata (Linn.) Wilczek] and peanut (Arachis hypogaea Linn.) as well as a sugarcane monoculture were conducted to study the impacts of intercropping on soil biological characteristics and bacterial diversity. The results showed that soil cultivable microorganisms, the activities of soil enzymes and microbial biomass carbon, nitrogen, and phosphorus were all significantly improved by intercropping with soybean and mung bean. Additionally, soil bacterial diversity and richness in sugarcane fields were also significantly enhanced by intercropping with soybean and mung bean. In addition, soil bacterial community structures in sugarcane fields can be altered by intercropping with different legumes. Proteobacteria, a high-nutrient-tolerant bacterial assemblage, became the dominant bacteria in the sugarcane-soybean and sugarcane-mung bean intercropped soils. Twenty four, 28, 26 and 27 dominant soil bacterial genera were found after the sugarcane-soybean, sugarcane-mung bean, sugarcane-peanut and sugarcane monoculture treatments, respectively. Sugarcane-mung bean intercropping being the most promising system for regaining and improving soil fertility and soil heath and facilitate agriculture intensification of sugarcane.

The influence of soil amendments on a native wildflower seed mix in surface mine restoration

With a multitude of physical, biological, and chemical soil characteristics disrupted or degraded during surface mining, it is challenging to achieve proper reclamation, much less restoration, post‐mining. We sought to assess the potential of a native wildflower seed mix (NWSM) to establish and achieve high vegetative coverage in the first season using soil amendments. We also evaluated the influence of amendments on community composition and soil quality. In May 2018, we seeded a NWSM on a surface mine in experimental plots treated with either inorganic fertilizer, spent mushroom compost, or left untreated. Plant coverage and community composition within experimental plots were assessed in October 2018. Soil samples were collected at the beginning and end of the season to identify potential changes in organic carbon, nitrogen availability, bulk density, and pH. First‐season vegetation results indicate that soil amendments may not be ecologically necessary or economically sensible for initial revegetation using a NWSM. Unamended plots surpassed compost‐amended plots and equaled or surpassed fertilizer‐amended plots in coverage, species richness, and proportion of seedlings present that originated from the mix. However, results from soil analyses suggest that compost may be beneficial to meeting surface mine restoration goals by improving important soil characteristics, such as percent organic matter, labile carbon, nitrate content, and pH, that could aid ecosystem recovery. Given the high degree of heterogeneity both within and between surface mines, future work should focus on identifying initial soil characteristics that could enable land managers to meet both reclamation and restoration goals using a NWSM.

YENİ RAYONLAŞMIŞ PAMBIQ SORTLARINDA XAM PAMBIĞIN FİZİKİ-MEXANİKİ GÖSTƏRİCİLƏRİNİN ÖYRƏNİLMƏSİ

In the course of the study, the biological characteristics of cotton, agrotechnical measures, soil and climatic conditions and technological factors that create conditions for the of a “fibrous coat”, “seed coat” and “seed crumbs” in the fiber were studied. The morphological characteristics of the varieties, the weight of the seed may differ depending on the soil-climatic and agrotechnical conditions, as well as the cultivation conditions. Key words: cotton, raw cotton, seed, technological features, variety, physical-mechanical features

Temporal Bacterial Community Diversity in the Nicotiana tabacum Rhizosphere Over Years of Continuous Monocropping.

Long-term continuous monocropping negatively influences the physicochemical and biological characteristics of cultivated soil, especially for the economically important crop of flue-cured tobacco that is intolerant to continuous monocropping. The underlying mechanism of soil sickness under continuous monoculture and the temporal dynamic changes over the tobacco life cycle among different monoculture time spans remain poorly characterized. In this study, high-throughput sequencing targeting the 16S rRNA gene phylogenetic marker was performed on 60 soil samples of rhizosphere soil from flue−cured tobacco in the replanting, growth and harvest period across 5, 10, and 20 years of a continuous monocropping system. Bacterial community diversity decreased with the increase in duration of continuous monocropping, and the rhizosphere microbiota was highly dynamic in the harvest period. The random forests algorithm identified 17 taxa as biomarkers and a model was established to correlate root microbiota with continuous monocropping time of flue-cured tobacco. Molecular ecological network analysis elaborated the differences and interactions in bacterial co-occurrence patterns under different monocropping systems. The co-occurrence microbial network was larger in size but there were fewer interactions among microbial communities with the increase in continuous monocropping duration. These results provide insights into the changes of flue−cured tobacco root microbiome diversity in response to continuous monocropping and suggest a model for successional dynamics of the root-associated microbiota over continuous monocropping time and development stage. This study may help elucidate the theoretical basis underlying obstacles to continuous monocropping and could contribute to improving guidance for tobacco production.

Covariation between plant biodiversity and soil systems in a European beech forest and a black pine plantation: the case of Mount Faito, (Campania, Southern Italy)

Both climate and land-use changes, including the introduction and spread of allochthonous species, are forecast to affect forest ecosystems. Accordingly, forests will be affected in terms of species composition as well as their soil chemical and biological characteristics. The possible changes in both tree cover and soil system might impact the amount of carbon that is stored in living plants and dead biomass and within the soil itself. Additionally, such alterations can have a strong impact on the detrital food web that is linked to litter decomposition. Although there are studies on the influence of plant diversity on soil physical and chemical characteristics, the effects on soil biological activity and carbon storage processes remain largely unknown. The aim of this study was to investigate and compare chemical and biological variables in covariation with plant communities in an autochthonous beech forest (Fagus sylvatica L.) and a black pine plantation (Pinus nigra J.F. Arnold subsp. nigra). Our results confirmed that the two communities were considerably different, with the old-growth beech community having a lower number of plant species and the pine community was in development as a consequence of anthropogenic activities. These aspects of the two communities were also reflected in the soil, with the beech soil having higher nitrogen levels and a more specialized microbial community compared to the pine soil, with most extracellular enzymes (such as peroxidase and chitinase) showing lower activity in the pine soil.

Glomus intraradices and Funneliformis mosseae am Strains Influence on Soil Physical, Biological and Chemical Characteristics in Tea Plantations in Kenya

Arbuscular mycorrhizal (AM) fungi occur over a wide range of agro climatic conditions and are geographically ubiquitous. Arbuscular mycorrhizal fungi are the medium of soil structure, they determine the flow of water, nutrients, and air, directs the pathways of root growth, and opens channels for the movement of soil animals. As the moderator of the microbial community, they also determine the metabolic processes of the soil. In other words, the mycorrhizal network is practically synonymous with ecosystem function. The tremendous advances in research on mycorrhizal physiology and ecology over the past 40 years have led to a greater understanding of the multiple roles of AMF in the ecosystem. The current study was informed due to the depletion of nutrients and poor soil microbiology in tea production whose production has declined in the recent years. The trial was conducted in the research and development greenhouse at the James Finlays Farm in Kericho County, Kenya. The experiment was laid out in a Randomized Complete Block Design (RCBD) with factorial arrangements of tea clones and mycorrhizae levels. The phosphorus treatments consisted of a standard rate of 107.66kg ha -1, two clones of the tea (S15/10 and SC 12/28) and two mycorrhizal strains (Funneliformis mosseae and Glomus intraradices) at two rates (50 kg ha-1 and 70 kg ha-1) and an untreated control without mycorrhizae. The soil pH was positively influenced by reducing the acidity content significantly where mycorrhizae strains were introduced with the highest unit change (1.3) was recorded on clone SC 12/28 at the 50 kg Mycorrhizae ha-1 rate. The same treatment also significantly increased the soil total phosphorus level (2.3 g/kg) compared to all other treatments with the least change observed on the control. Application of AMF strains Glomus intraradices and Funneliformis mosseae is recommended in tea production at the rate of 50 kg ha-1 which improves and enhances the general positive characteristics of soil health.

Temporal Soil Bacterial Community Responses to Cropping Systems and Crop Identity in Dryland Agroecosystems of the Northern Great Plains

Industrialized agriculture results in simplified landscapes where many of the regulatory ecosystem functions driven by soil biological and physicochemical characteristics have been hampered or replaced with intensive, synthetic inputs. To restore long-term agricultural sustainability and soil health, soil should function as both a resource and a complex ecosystem. In this study, we examined how cropping systems impact soil bacterial community diversity and composition, important indicators of soil ecosystem health. Soils from a representative cropping system in the semi-arid Northern Great Plains were collected in June and August of 2017 from the final phase of a 5-year crop rotation managed either with chemical inputs and no-tillage, as a USDA-certified organic tillage system, or as a USDA-certified organic sheep grazing system with reduced tillage intensity. DNA was extracted and sequenced for bacteria community analysis via 16S rRNA gene sequencing. Bacterial richness and diversity decreased in all farming systems from June to August and was lowest in the chemical no-tillage system, while evenness increased over the sampling period. Crop species identity did not affect bacterial richness, diversity, or evenness. Conventional no-till, organic tilled, and organic grazed management systems resulted in dissimilar microbial communities. Overall, cropping systems and seasonal changes had a greater effect on microbial community structure and diversity than crop identity. Future research should assess how the rhizobiome responds to the specific phases of a crop rotation, as differences in bulk soil microbial communities by crop identity were not detectable.

Assessment of earthworms as an indicator of soil degradation: A case‐study on loess soils

AbstractSoil degradation restricts the development of agriculture, and the degree of soil degradation is related to land use type, and efficient evaluation methods are helpful for the timely implementation of remedial measures to ensure soil sustainability. Earthworms are directly affected by the deterioration of soil properties during the degradation process. The feasibility of using earthworms to assess soil degradation, however, still needs to be verified. In our Loess Plateau study, earthworm biomass, density, and diversity (Shannon‐Wiener, species richness, and Pielou's evenness) were investigated under nine different land use types (natural woodland, shrubland and grassland; planted woodland, shrubland and grassland; and cropland, orchard, abandoned land) and we analyzed their relationships with soil degradation. Our results showed earthworm biomass, density, and diversity associated with a low degree of degradation were significantly higher than those associated with a high degree of degradation. Earthworms can comprehensively characterize the physicochemical properties and biological characteristics of soils under different land use types. Linear correlations showed a significant relationship between the soil degradation index and the earthworm indices, indicating that the latter could be used to effectively evaluate and represent the degree of degradation of soils on the Loess Plateau over a certain degradation range. Nevertheless, this evaluation method requires further validation before wider use.

Soil properties and microbial abundance explain variations in N2O fluxes from temperate steppe soil treated with nitrogen and water in Inner Mongolia, China

Microbe-mediated soil nitrification and denitrification processes affect the variations in soil N2O fluxes. Researchers are concerned about how the abundances of nitrifiers and denitrifiers and the N2O fluxes from temperate semi-arid grassland soil vary as nitrogen (N) and water inputs vary. In this study, we report the results from a field experiment that was set up in a temperate semi-arid grassland area in northern China in May 2017. In August 2018, we collected samples to investigate how a range of physical, chemical and biological characteristics of soil, including the pH, moisture, dissolved organic carbon content (DOC) and available N content, N2O fluxes, and the abundances of ammonia oxidizers and denitrifiers in the soil, changed after N (4 g N·m−2·year−1 NH4NO3) and water (112.5 mm·year−1) were added over a period of 1 year. We analyzed the abundances of AOA amoA, AOB amoA, nirS, nirK and nosZ using quantitative PCR. We found that the soil N2O emissions were negatively affected by the water additions, but were not affected by the N additions. We also found that the AOA amoA and nosZ genes responded positively to the N additions. Watering had a positive effect on the nirS gene abundance, while N additions and water together intensified the effect of only water on the nirS gene abundance. The nirS gene abundance, soil pH, and DOC content explained 46.1%, 20.1% and 12.0% of the variations in the soil N2O fluxes, respectively. These results provide improved insights into how microorganisms affect N cycling, and may be used to help predict how soil N2O fluxes might change in the future, as N deposition and precipitation change.

IMPLEMENTATION OF MODERN TECHNOLOGIES TO ALLEVIATE

Introduction. Urban perennial plantations are exposed to numerous anthropogenic pollutants, recreational load, etc. As a result, the physical and chemical properties of the soil deteriorate, the development of useful soil microflora is inhibited, the phytosanitary properties of soil ecosystems worsen, the intensity of mineralization processes and availability of macro- and micronutrients for plants drops down, and the concentration of toxic substances increases, which leads to soil sickness. Problem Statement. Today, in Ukraine, the causes and features of soil sickness manifestation in urban ecosystems have been virtually unexplored, and there has been no environmentally sound approach to overcoming negative consequences of this phenomenon. Purpose. To implement environmentally sound technology for overcoming soil sickness in urban green areas through the integrated use of the natural silicon containing mineral analcite and a synthetic analog of allelochemical (salicylic acid). Materials and Methods. The experimental sites have been established in the most polluted and anthropogenically disturbed green areas of the Obolon District in Kyiv. The content of micro- and macro-elements, the main ecological-trophic groups of microorganisms have been evaluated, the directions of microbiological processes have been assessed with the use of mineralization and immobilization coefficients. Plant vitality has been determined by the degree of foliar injury, crown defoliation, photosynthetic pigment content, and activity of enzymatic antioxidants in leaves. Soil allelopathic activity has been determined by the bioassay technique. Results. Physical, chemical, and biological processes related to soil-sickness in urban areas have been studied and approaches to control these processes have been determined. The innovative technology to alleviate soil sickness in urban green areas has been tested. Conclusions. The advantage of the proposed technology is a complex synecological approach that which provides optimization of agrophysical, agrochemical, and biological characteristics of soil (optimal pH level, balanced content of mineral nutrients, elimination of toxicity), enhances the adaptive potential of cultivated plants to negative biotic and abiotic factors including phytopathogens.

Gene analysis reveals that leaf litter from Epichloë endophyte-infected perennial ryegrass alters diversity and abundance of soil microbes involved in nitrification and denitrification

Although Epichloë endophytes are present only in aboveground tissues of grasses they indirectly influence soil biological characteristics through increased litter incorporation and root exudation. Epichloë endophytes have been reported to affect the decomposition rates of litter by altering litter quality and microbial decomposers to affect soil characteristics. However, it is not well-studied that underlying effects on functional genes involved in nitrification and denitrification after incorporation of litter containing Epichloë endophytes into soil. We collected soil samples at S0 (first litter incorporation), S1 (second litter incorporation), S2 (third litter incorporation) and S3 (120 days after the third litter incorporation) times after incorporation of litter that was either infected with the fungal endophyte Epichloë festucae var. Lolii or free of Epichloë endophyte, respectively. . We sampled the soil fororganic carbon (OC), total nitrogen (TN), total phosphorus (TP), ammonium nitrogen (NH4+-N: AN), nitrate nitrogen (NO3−-N: NN), soil microbial biomass carbon (MBC), nitrogen (MBN), ammonia-oxidizing bacteria (AOB-amoA) and ammonia-oxidizing archaea (AOA-amoA) functional genes for nitrification, nitrite reduction (nirS and nirK) and nitrous oxide reduction (nosZ) functional genes for denitrification. We found that Epichloë-infected plant increased the soil properties (OC, TN, AN, NN) and microbial biomass C in S1 to S3 times, and microbial biomass N in S2 and S3 times, but reduced soil pH in S1 times and the C_N ratio in S2 and S3 times by litter incorporation. The absolute abundance of the AOB-amoA functional gene at S1 and S3 times and relative abundances of Planctomycetes, Methylobacterium, Nitosomonas, Gemmata, Geodermatophilus and Sinorhizobium in the nirK functional gene community were significantly higher in soil with Epichloë-infected litter compared to soil with Epichloë-free litter at S1 and S3 times. While the absolute abundance at S1 and S3 times and diversity at S3 times of the nirK functional gene, and the absolute abundance at S1 to S3 times and diversity at S1 times of the nosZ functional gene, and relative abundance of Proteobacteria in the AOB-amoA functional gene were significantly lower in soil with litter containing Epichloë endophyte than that of soil with litter without the endophyte. The soil moisture, and the contents of TP, OC, AN and MBN were the best explanatory variables for the altered microbial community. Our results provide a new understanding of the responses of soil nitrification and denitrification genes through incorporation of litter containing Epichloë endophytes into soil.

A Study on the Physical, Chemical, Biological, and Molecular Characteristics of Coastal Saline Soils under a Rice-Based Cropping System

Carbon (C) dynamics and soil biology are affected by the varying salinity present in coastal agro-ecosystems, which decreases from the coast in landward. The research's goal is to look at coastal saline soils through the lens of a rice-based cropping system from a physical, chemical, biological, and molecular standpoint.

Possible Toxicological Effect of Pesticides, Cypermethrin on Earthworm (Esiania fetida)

Pollution is the preface of infect into an environment, may also defined as an unwanted modify in the physical, chemical and biological characteristics of air, water and soil which influence human life, lives of other useful alive plants and animals, industrial progress, alive conditions and florescent property Water is the most necessary & major necessaries of life. One can rarely survive without water also for a few days. At that 2/3 of the world’s float up region is enclosed by water but yet we are blank. An incubation study was conducted to know the toxicity level of Fipronil in soil fauna by using earthworm species Eisenia fetida as a biomarker. The earthworm were incubated in the spiked soil, with concentration of 0.5 ppm, 0.6 ppm, 0.7 ppm,0.8 ppm, 0.9 ppm for a period of 24hours and 48 hours. From the study, 50% mortality was observed in 0.5 ppm. The LC50 concentration was calculated from that it was clear that Cypermethrin is toxic to earthworm.

Characterization of soil fungal community associating with suppressive soil to Verticillium yellows disease of Chinese cabbage

AbstractChinese cabbage yellows is a major economically important disease caused by Verticillium dahliae and V. longisporum in Japan. Although it has existed in Chinese cabbage fields that show suppressiveness against the disease, their mechanisms remain unclear. To uncover soil biological characteristics associated with disease suppressiveness, we performed comparative analyses of bacterial and fungal communities among different field soils showing different disease severities of Chinese cabbage yellows in the Gunma Prefecture in Japan. Bacterial and fungal communities in these soils were analysed using polymerase chain reaction–denaturing gradient gel electrophoresis (PCR–DGGE), which indicated that a specific DGGE band with metrics (Rf value) of approximately 28.9 tended to specifically appear in soils with lower disease severities, whereas the nucleotide sequence analysis revealed that the DGGE band was closely related to the sequences that belonged to the Chaetomiaceae family. The fungal strain S69 corresponding to the DGGE band 28.9 was isolated from disease‐suppressive field soil, and the results of the nucleotide sequence analysis suggested that the strain was closely related to Thielavia terricola, a member of the Chaetomiaceae family. The pot experiments revealed that Chinese cabbage yellows was suppressed by strain S69 propagule treatment into soils infested with V. longisporum. Thus, it is suggested that the fungal strain S69 contributed to the soils’ disease suppressiveness.

Possible Toxicological Effect of Pesticides, Fipronil On Earthworm (Eudrilus eugeniae)

Pollution is the preface of infect into an environment, may also defined as an unwanted modify in the physical, chemical and biological characteristics of air, water and soil which influence human life, lives of other useful alive plants and animals, industrial progress, alive conditions and florescent property Water is the most necessary & major necessaries of life. One can rarely survive without water also for a few days. At that 2/3 of the world’s float up region is enclosed by water but yet we are blank. An incubation study was conducted to know the toxicity level of Fipronil in soil fauna by using earthworm species Eudrilus eugeniae as a biomarker. The earthworm were incubated in the spiked soil, with concentration of 17ml, 18ml, 19ml, 20ml for a period of 24hours and 48 hours. From the study, 50% mortality was observed in 17ml. The LC50 concentration were calculated from that it was clear that Fipronil is toxic to earthworm.

Assessing soil quality under long-term organic vis-a-vis chemical farming after twelve years in north-western India

Sustaining soil fertility and enhancing food production on smallholder farms is a great challenge in the Indo-Gangetic plains (IGP). Soil fertility parameters viz., physical, chemical and biological, though intrinsically linked to one another in the soil environment, are often studied in isolation. This work adds value to analyses of all these three components of soil quality influenced by different cropping systems under organic and chemical farming by correlating all these parameters, otherwise left unexplored. The study compared soil physical, chemical and biological characteristics in relation to long term organic and chemical farming in a sandy loam soil. The field experiments were conducted at Punjab Agricultural University, Ludhiana, India, with two farming systems in main plots for 12 seasons and four cropping systems in sub-plots for 4 seasons. The organic farming with green manuring (GM) to basmati rice and farmyard manure to wheat in basmati rice - wheat cropping system significantly increased soil water holding capacity, mean weight diameter, soil organic carbon, cation exchange capacity, dehydrogenase activity and basal soil respiration by 42.3, 62.7, 48.9, 59.0, 55.6 and 50.3%, respectively than with chemical farming. The crop productivity was 33.9% higher in organic than chemical farming, resulting in higher net returns under GM based organic farming. Principal component analysis (PCA) distincted organic farming from the chemical farming under different cropping systems based on basal soil respiration and cation exchange capacity in PC1 (explaining 93.1% of total variability), and the carbohydrate carbon and pH in PC2 (19.5% variability). These indicators are most influential for studying soil quality under organic farming and GM based cropping systems.