Application of Micronutrients in Rice-Wheat Cropping System of South Asia

Rice-wheat cropping system (RWCS) is one of the most important cropping systems in South Asia. However, sustainability of this system is under threat owing to several factors, of which deficiency of micronutrients particularly zinc (Zn), boron (B) and manganese (Mn) is one of the major problems. Continuous rotation of rice and wheat, imbalanced fertilizer use and little/no use of micronutrient-enriched fertilizers induce deficiencies of Zn, B and Mn in the RWCS of South Asia. Here we review that (i) imbalanced fertilizer use and organic matter depletion deteriorate soil structure resulting in low efficiency of applied macro- and micro-nutrients in RWCS.(ii) The micronutrients (Zn, B and Mn) are essentially involved in metabolism of rice and wheat plants, including chlorophyll synthesis, photosynthesis, enzyme activation and membrane integrity.(iii) Availability and uptake of Zn, B and Mn from rhizosphere depend on the physico-chemical soil properties (which differ under aerobic and anaerobic conditions) including soil pH, soil organic matter, soil moisture and interaction of these micronutrients with other nutrients.(iv) Plant ability to uptake and utilize the nutrients is affected by several plant factors such as root architecture, root hairs, transport kinetics parameter and root exudates.(v) Crop management and application of these microelements can help correct the micronutrients deficiency and enhance their grain concentration.

Long-Term Effects of Cover Crops on Crop Yields, Soil Organic Carbon Stocks and Sequestration

A 12-year cover crops study on the effects on SOC sequestration, storage, retention and loss and corn and soybean yields was conducted in southern Illinois. The use of cover crops for the maintenance and restoration of soil organic carbon (SOC) and soil productivity of previously eroded soils were evaluated. No-till (NT), chisel plow (CP), and moldboard plow (MP) treatment plots with and without cover crops were established in 2001. The plot area was on sloping with a moderately well drained, eroded soil. The average annual corn and soybean yields were statistically the same for NT, CP, and MP systems with and without cover crops. By 2012, the cover crop treatments had more SOC stock than that without cover crops for the same soil layer and tillage treatment. The NT, CP, and MP treatments all sequestered SOC with cover crops. A pre-treatment SOC stock baseline for rooting zone was used to validate the finding that cover crops sequestered SOC in the topsoil, subsoil and root zone of the NT, CP and MP treatments during the 12-year study. Additional sequestered SOC was lost as a result of being transported off of the plots and retained in lower slopes, transported to the stream or released to atmosphere.

Growth and yield of two grain crops on sites former covered with eucalypt plantations in Koga Watershed, northwestern Ethiopia

Farmers in the highlands of Ethiopia often plant Eucalyptus on their farmlands. However, growing Eucalyptus, especially on farm- lands suitable for crop production has become a great concern due to its alleged long-term site effects. Our study was conducted at Koga water- shed, Mecha District, northwestern Ethiopia to investigate whether crop- lands afforested with Eucalyptus camaldulensis Dehnh. can be restored for annual crop production after tree harvest. We compared growth and yield of two agricultural crops, barley （Hordeum vulgate L.） and finger millet （Eleusine coracana （L.） Gaertn.）, grown in clear-felled stands of E. camaldulensis and continuously cultivated croplands at twelve paired farmlands under a conventional farming system. Plant height and dry matter production were evaluated as indices of crop growth, while grain weight was evaluated as an index of crop yield. Crop growth and yield measurements averaged over all farmlands differed between land-use types. For both crops, plants grown on clear-felled stands were taller than on croplands. Dry matter production and yield were also significantly greater in crops cultivated on clear-felled stands. Cropland aboveground and belowground dry matter productions were lower by 31.8 and 25.4% for barley and 32.8% and 37% for finger millet, respectively. Clear-felled stands gave an average yield of 2.91 t.ha-1 for barley and 3.27 t.ha-1 for finger millet while cropland gave a yield of 1.97 and 2.31 t.ha-1 for barley and finger millet, respectively. Farmers also responded that farm plots on former eucalypt plantations showed greater crop growth and yield thandid continuously cultivated croplands. Farmers perceived that Eucalyptus plantations improved soil fertility and they preferred clear-felled stands for crop production and wished to plant Eucalyptus on their farmlands. Our results suggest that conversion of agricultural lands to Eucalyptus plantations can increase post-felling yields of cereal crops.

Rooting of Stem Cuttings with Different Indole 3 Butyric Acid (IBA) Treatments and Development of Micropropagation Protocol for <i>Piper betle</i>L. Node Culture

The present study, conducted during 2016 and 2017 seasons, aimed to investigate the effect of IBA on rooting of Piper betle L. stem cuttings (softwood and semi-hardwood). The experiment was undertaken in misting house field 2 UPM using the sand media to determine the adventitious roots initiation and development using the histological method. The cuttings were treated with different IBA concentrations (0, 500, 1000, 1500 and 2000 mg/L). The nodes explants were used in the development of a protocol for in vitro propagation of P. betle L., with different concentrations of Clorox with different times of immersion (20% Clorox 10 minutes, 30% Clorox 10 minutes, 20% Clorox 20 minutes, and 30% 20 minutes). In multiplication of the plantlets, Murashige and Skoog (MS) medium with different concentrations of BAP (0, 0.5, 1.0, 2.0 mg/L) were used to investigate the rooting of the explants. The results indicated that the types of the cuttings were different in the rooting capacity and the length of the roots. Moreover, it was found that in comparison with the control treatment, by a rise in the concentrations of the IBA, there was a significant upsurge in the rooting percentage, the root diameter, and the number of the roots. The results indicated that the types of cutting with 1000, 1500 and 2000 mg/L IBA perform better in the root percentage (100%) in the semi hardwood cuttings. The best results, however, were 2000 mg/L IBA in the semi hardwood cuttings, with the number of the roots to be 35.05, and the fresh weight of the roots to be 3.94 g, the dry weight of the roots to be 0.33 g, the length of the roots to be 391.88 cm, the roots diameter to be 1.21 mm, the surface area of the roots to be 121.83 cm2, and the root volume to be 2.99 cm3. Nonetheless, the optimal concentration of Clorox with the time immersion was 20% with the 20-minute immersion time, which produced a shoot induction percentage of 30% dead explants and a mean number of 70.00 shoots per explant and the optimal concentration of benzylaminopurine (BAP) at 1.0 mg/L. It is of note that a shoot induction percentage of 22.29% and a mean number of 4.1% number of auxiliary bud per treatment. P. betle shoots in MS medium without PGR MS (0.0) yielded a good rooting.

The Use of High Tunnels to Produce Fruit and Vegetable Crops in North America

High tunnels have been used in the United States for more than 50 years, and growers are encouraged to use them more frequently through government cost-share programs. Research on fruits and vegetable production systems has focused on high value crops such as tomato, salad greens, and several fruit crops. Maintaining soil quality and controlling insects and diseases are all issues that growers face. This review looks at current research on these issues as well as economic considerations addressed in the scientific literature. Global statistics and reports are also reviewed that complement the North American studies. Gaps in our understanding are identified, and directions for future research are suggested.

The Compatibility Effects of Biochar-Vermicompost Mixes on Crop Productivity

This study sought to establish the compatibility effects of biochar/vermin-compost application on growth and yield of maize and cabbages. Biochar application rate was at 3 to 4% of soil weight. Biochar was mixed in various proportions to come up with treatments which were 100% vermicompost, 50/50% biochar： vermicompost, 75/25% biochar： vermicompost and 100% biochar. The experiment was repeated twice and arranged as a completely randomized design and replicated five times. The study established that maize yield increased with application of biochar from 25% to 50%. In the cabbage trial, comparable results in plant height, leaf numbers and final yield was obtained with 100% vermicompost application, 50% and 75% biochar inclusion. When biochar was applied at 100%, noticeable reduction in plant performance was noted. It is recommended to use biochar as a bio-fertiliser at 50/50% biochar： vermicompost in maize and cabbage production.

Assessment of Seed-Borne Plant Pathogenic Fungi Associated with Rice Crop in South-Eastern Nigeria

This study was conducted to assess the incidence of seed-borne fungi on rice seeds sourced from the major rice growing areas of South-Eastern Nigeria. The rice seeds were collected during the dry seasons between 2009 and 2010. Four hundred rice seeds randomly collected and surface sterilized by washing in 3% sodium hypochlorite and rinsed two times with sterile distilled water were placed in three circular rings inside the Petri dishes. The incubation was done one after the other for each variety from all the locations. Ten fungi species from eight genera were isolated from the rice seeds in all the rice growing areas of South-Eastern Nigeria. The fungi pathogens vary from one locality to another, as well as the frequency of occurrence. The pathogens isolated include： Fusarium moniliforme, F. solani, F. oxysporium, Aspergillus spp., Botridiploidia spp., Helminthosporium spp., Penicillium spp., Trichoconis padwickii, Curvularia oryzae and Phoma oryzae. Though, there was the presence of some seed-borne fungi in the rice seeds from the areas studied, most of the cultivars experienced up to 90% germination. But some cultivars had very low germination. IR 1416 from Arochukwu and GB90 from Arondiuzogu had less than 1% germination. This study shows that seed-borne organisms are major constraint in rice production in the South-Eastern states of Nigeria as a result of low seed germination stemmed from infestation of fungi organisms in the seeds.

Grasshopper Incidence and Severity of Damage as Influenced by Cyanogenic Potential in Leaf Tissue of Cassava (Manihot esculenta Crantz)

This study assessed the effect of cyanogenic potential (CNP) in leaf tissue on grasshopper incidence and severity of damage in cassava for the identification of parents with desired complementary traits for crossing. The experiment was conducted at the Foya Wulleh, Njala experimental site in Sierra Leone during 2020 and 2021 cropping seasons in a randomized complete block design with three replications. A total of 30 genotypes comprising 26 breeding lines, two improved and two local genotypes were assessed. Results showed a significant (p < 0.05) linear relationship between leaf CNP and grasshopper infestation (incidence and severity of damage) among cassava genotypes. Findings showed that the higher leaf CNP, the lower the grasshopper infestation in cassava genotypes. About two genotypes (Cooksoon and Cocoa) had low leaf CNP;three genotypes (TR0020, TR0037 and TR0013) CNP had moderately low leaf CNP;eight genotypes (SLICASS 6, TR0029, TR0032, TR0011, TR0012, TR0016-1/17, TR0002 and TR0010) had intermediate leaf CNP;seven (TR0009, TR0015-1/17, TR0036, TR0022-1/17, SLICASS 4, TR0007 and TR0026-1/17) had moderately high leaf CNP;eight (TR0008, TR0019-1/17, TR0006, TR0005, TR0021, TR0021-1/17, TR0022 and TR0024-1/17) had high leaf CNP;and two genotypes (TR0001 and TR0018-1/17) had very high leaf CNP. This suggests the indirect dependence of leaf cyanogenic potential on grasshopper infestation (incidence and severity of damage) in cassava that could be exploited for the genetic improvement of cassava for improved resistance to grasshopper infestation, nutrition and utilization of the crop.

Determination and Quantification of Proximate and Mineral Composition for 20 Improved Sorghum Varieties Grown in Machache, Lesotho

Twenty varieties of improved sorghum were grown in Machache at the Department of Agricultural Research station, located (29˚22'60"S and 27˚52'0"E) in the central foothills of Lesotho in Maseru district. The varieties were planted in a randomized complete block design. At maturity, they were harvested, dried, threshed, milled and analyzed in the crop science laboratory at the National University of Lesotho. The proximate and mineral contents were analyzed from samples in a completely randomized design with three replicates. The proximate composition parameters measured were crude proteins, crude fiber, crude fat, moisture content, and carbohydrates. The minerals analyzed were, phosphorus, sodium, calcium, magnesium, potassium, copper, zinc, iron, and magnesium. The results showed the nutritional contents ranging from (4.7% - 16.16%), (0.35% - 2.10%), (1.25% - 4.00%), (71.60% - 84.06%), (5.53% - 10.18%), for protein, fat, fiber and carbohydrate, and moisture content, respectively. Mineral content ranged from (1342.96 - 3500.34 mg/kg), (25.97 - 185.25 mg/kg), (50.71 - 511.71 mg/kg), (29.35 - 4542.13 mg/kg), (577.19 - 3041.52 mg/kg), (0.25 - 4.07 mg/kg), (1.96 - 18.61 mg/kg), (67.14 - 122.96 mg/kg), (4.73 - 11.39 mg/kg) for phosphorus, sodium, calcium, magnesium, potassium, copper, zinc, iron, and manganese respectively. The following varieties were found to have the highest and appreciable amounts of nutrients and minerals that are crucial in the country diet;protein content was KARI Mtama 1, zinc, IESX 16 2533-SB-SSI-19, and iron IESX 16 2535-SB-SSI-34.

Synergistic Interactions of Soil and Vegetation in Agroforestry Systems in Mitigating Climate Change in Upper East Region, Ghana

Climate change has been a global pandemic with its adverse impacts affecting environments and livelihoods. This has been largely attributed to anthropogenic activities which generate large amounts of Green House Gases (GHGs), notably carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) among others. In the Upper East of Ghana, climate change manifests in erratic rainfalls, drought, high temperatures, high wind speeds, high intensity rainfall, windstorms, flooding, declining vegetation cover, perennial devastating bushfires etc. Practices such as burning farm residues, use of dung as fuel for cooking, excessive application of nitrogenous fertilizers, and deforestation that are prevalent in the region exacerbate the situation. Although, efforts made by governmental and none-governmental organizations to mitigate climate change through afforestation, agroforestry and promotion of less fuelwood consuming cook stoves, land management practices antagonize these efforts as more CO2 is generated than the carrying capacity of vegetation in the region. Research findings have established the role of trees and soil in carbon sequestration in mitigating climate. However, there is limited knowledge on how the vegetation and soil in agroforestry interplay in mitigation climate change. It is against this background that this review seeks to investigate how vegetation and soil in an agroforestry interact synergistically to sequester carbon and contribute to mitigating climate change in Upper East region of Ghana. In this review, it was discovered soil stored more carbon than vegetation in an agroforestry system and is much effective in mitigating climate change. It was found out that in order to make soil and vegetation in an agroforestry system interact synergistically to effectively mitigate climate change, Climate Smart Agriculture practice which integrates trees, and perennials crops effectively mitigates climate. The review concluded that tillage practices that ensure retention and storage of soil organic carbon (SOC) could be much effective in carbon sequestration in the Savannah zones and could be augmented with vegetation to synergistically mitigate climate change in the Upper East region of Ghana.

Evaluation of Rhizobium tropici-Derived Extracellular Polymeric Substances on Selected Soil Properties, Seed Germination, and Growth of Black-Eyed Peas (Vigna unguiculata)

Rhizobium tropici-derived extracellular polymeric substances (EPS) have been used in soils to enhance soil structures and mitigate soil erosions. However, information on their use to improve soil health and fertility indicators, and plant growth is limited. In a greenhouse study, we investigated their effects on some soil health, soil fertility indices, and the growth of black-eyed peas (Vigna unguiculate). Results showed that soils incubated with EPS significantly increased basal soil respiration, soil microbial biomass, permanganate oxidizable carbon (POC), and potentially mineralizable nitrogen (PMN). The EPS shifted microbial populations from bacteria to fungi and Gram (−ve) to Gram ( ve) bacteria. However, it had little or no effects on soil pH, soil organic matter (SOM), and cation exchange capacity (CEC). The EPS decreased soil moisture loss, increased soil aggregate stability, but delayed blacked-eyed peas germinations in the soils. At 0.1% (w/w) concentrations in soils, there was increase in plant root nodulations and vegetative growth. This study was carried out within 40 days of incubating soils with EPS or growing the black-eyed peas in a greenhouse study. The plant growth parameters were taken before flowering and fruiting. Further studies of the effects of incubating soils with the extracellular polymeric substances on plant growth. Soil microbial biomass, microbial diversities, and other soil fertility indices are deemed necessary.

Structural and Functional Annotation of Hypothetical Protein of Fusobacterium nucleatum Strain MJR7757B: An in Silico Approach

Fusobacterium nucleatum is an anaerobic, commensal, gram-negative oral bacterium that is carcinogenic and causes a wide range of human diseases. The present study focused on the analysis of the hypothetical protein, HMPREF3221_01179, derived from F. nucleatum strain MJR7757B, employing various computational methods to anticipate both its structure and functional characteristics. NCBI conserved domain analysis, NCBI BLASTp and MEGA Phylogenetic tree study characterize the target protein as an outer membrane efflux protein (ToIC family) which facilitate the bacterial transmembrane transport. With a molecular weight of 52120.02 Da, an isoelectric point (pI) of 8.33, and an instability index of 29.47, the protein is anticipated to exhibit good solubility in the extracellular space and crucial stability for pharmaceutical applications. The protein’s structure meets quality standards during the construction and refinement of its 3D model. The efflux inhibitor Arginine beta-naphthylamide exhibits a significant binding affinity (-7.1 kcal/mol) to the binding site of the target protein. The in-silico analysis improves the understanding of the protein and facilitates future investigations into therapeutic medication.

Genetic Diversity and Combining Ability of Developed Maize Lines to Realize Heterotic and High Yielding Hybrids for Arid Conditions

Developing high-yield maize hybrids is critical for sustaining maize production,especially in the face of rapid climate changes and the growing global population.Exploring the genetic diversity and combining ability in parental inbreds is needed for developing such high-yielding hybrids.Consequently,this study aimed at evaluating parental genetic diversity employing simple sequence repeats(SSR)markers,estimating effects of general(GCA)and specific(SCA)combining abilities for grain yield and yield contributing characters,identifying high yielding hybrids,and evaluating the association of SCA effects and performance of hybrids with genetic distance.Half-diallel mating scheme was utilized to develop 21 F_(1) hybrids from seven diverse maize inbred lines.The F_(1) hybrids along with check hybrid(SC-10),were investigated in a field trial over two growing seasons under arid conditions.The assessed F_(1) hybrids displayed significant genetic variations across all recorded traits.The inbreds P_(1) and P_(3) were detected as effective combiners to develop early maturing hybrids.Additionally,P_(3) and P_(4) were recognized as better combiners for improving grain yield and yield attributed characters.The hybrids P_(1)×P_(5) and P_(4)×P_(7) displayed significant SCA effects coupled with favorable agronomic performance.These hybrids are recommended for further evaluation and release as variety for arid environments to increase total maize production and contribute to food security.The alleles per locus differed between 2 and 5,with average of 3.5 alleles/locus.The polymorphic information content(PIC)altered between 0.21 to 0.74,with a mean of 0.56.Unweighted neighbor-joining tree grouped the inbred lines into three clusters,providing a valuable tool to decrease the crosses needed to be assessed in the trial field.Parental genetic distance varied from 0.63 to 0.90,averaging 0.79.The relationship between genetic diversity assessed through SSR markers and SCA effects was insignificant for all considered traits.Otherwise,SCA demonstrated a significant correlation with hybrid performance,suggesting that SCA serves as a reliable predictor for hybrid performance.The assessed maize inbred lines and developed hybrids revealed substantial genetic variability,offering valuable resources for enhancing maize productivity under arid conditions.The identified promising inbred lines(P_(1),P_(3),and P_(4))might be regarded as effective combiners for developing early-maturing genotypes and excellent combiners for enhancing yield attributes.Notably,the developed hybrids P_(1)×P_(5) and P_(4)×P_(7) possessed significant SCA alongside superior yield traits.SCA demonstrated a significant correlation with hybrid performance,suggesting its potential as a reliable predictor for the performance of developed hybrids.

The Impact of Changing Climate on Agroforestry Tree Distribution across Agroecological Zones of Nigeria: MaxEnt Modelling Perspective

The survival of agroforestry tree species in sub-Saharan Africa is essential for sustainable livelihoods, particularly in the semi-arid environment. Drought in the Agroecological zones (AEZ) of Nigeria is one of the environmental factors limiting parkland tree regeneration. Species distribution modelling offers the opportunity to predict future distributions of plant species based on current distribution data and bioclimatic variables. Maxent (maximum entropy) model was employed to predict the future tree distribution in AEZ parklands, under the four Representative Concentration Pathway (RCP) climate change prediction using current tree distribution (presence-only data) along a transect across three agroecological zones. The spatial data used were 19 bioclimatic variables and presence-only data for the two most important tree species—Parkia biglobosa and Vitellaria paradoxa. The result showed a drastic reduction (>45%) in the suitability of farmlands across predictions observed in the studied agroecological zones. The 2050 scenario in both species predicted areas had an increasing mid-range potential, over 44% lower suitability in sampled AEZ distribution predictions. The future prediction potential distribution maps for year 2070 of both species displayed large variations in suitability compared to 2050, showing a significant increase (up to 53%) in areas climatically suitable for both species to regenerate and thrive. This is attributed to over increased annual evapotranspiration, despite increasing seasonal precipitation. This study highlights the need for more climate-smart regeneration and improved restoration strategies to reduce land degradation as climate conditions change over time.

Advanced Insights into Goliathus orientalis (Coleoptera: Scarabaeidae) of Tanzania

Members of the Goliathus group in the order Coleoptera, family Scarabaeidae and the sub-family Cetoniidae is one among essential ecological insects worldwide with scanty documentation in Tanzania. The country was among the first point of collection of the specimen by Moser (1909) but subsequent attempts to locate and collect the specimen were unsuccessful possibly due to changed habitat and behaviour of Goliathus. Much of published work about the insect are based on the morphological characteristics of collected specimen which led to designation of six major species namely;Goliathus goliatus, G. cacicus, G. regius, G. albosignatus, G. orientalis and G. usambarensis, the last two being considered to exist in Tanzania. The current study reports on successful identification of habitats using biological cues and subsequently collected several Goliathus specimen that had been difficult to trace for more than a century. New insights into correct identity of the species by using a combination of morphological and molecular techniques have been set. The study has resolved that only one species, Goliathus orientalis with five sub-species exist in Tanzania.

Oviposition Site Preference and Its Effects on Subsequent Development of Variegated Grasshopper (Zonocerus variegatus L.) under Laboratory Conditions

Female grasshoppers can affect the fitness of their offspring through their selection of oviposition site. Knowledge of soil type on oviposition, and its effects on subsequent development can provide guidelines for habitat manipulations that reduce the harmful effects of these pests on farmers fields. The influence of soil types on the oviposition site preference of variegated grasshopper (Zonocerus variegatus L.) reared some cassava (Manihot esculenta Crantz) varieties, was investigated in a cage trial carried out at the Bio factory laboratory, School of Agriculture and Food Sciences, Njala University, Sierra Leone during 2022/2023. The treatments comprised three soil types (Sandy, Loamy and Clay), each with three replications laid out in a randomized complete block design (RCBD) in wooden cages. Data were collected on the following development parameters including, Net reproductive growth ratio (R0), Generation time (Tc), Intrinsic rate of increase (rm), Finite rate of increase (), Doubling time (Dt), and overall survivorship. Findings revealed that, Z. variegatus L. preferred sandy soil in which, on average, most eggs were deposited (338, 6.62 4.40), followed by loamy soil, 286 (5.53 3.96), and then, clayey soil, 200 (3.91 3.85);though, the differences were not significant. This study established that Z. variegatus deposited more eggs in sandy soil > loamy soil > clayey soil, respectively;and subsequent survivorship of the immature unto mature adult insect, revealed a similar order. This indicates that the sandy soil is the most preferred substrate for oviposition and subsequent development into adult insects.

Effects of climate,soil and water source on determining exchangeable copper concentration in lowland paddy fields in Sri Lanka

Copper(Cu)is an essential micronutrient for rice.However,the current status of Cu in Sri Lankan paddy soils is not known.Therefore,the current study was conducted to determine the distribution of exchangeable Cu concentration and examine the interactive effects of the agro-climatic zone(ACZ),soil order,and water source in determining the exchangeable Cu concentration in lowland paddy fields in Sri Lanka.A total of 7,544 soil samples representing six ACZs,six soil orders,and three water sources were collected using a stratified random sampling approach.Soil exchangeable Cu fraction was extracted in 0.01 M CaCl_(2)and measured using Inductively Coupled Plasma Mass Spectrophotometry.Exchangeable Cu concentration was in the range of 0.04−728μg·kg^(−1)with a mean value of 62.4μg·kg^(−1).Only 5%of the soil samples tested had Cu concentration greater than 200μg·kg^(−1)indicating a widespread Cu deficiency in Sri Lankan paddy fields(i.e.critical level causing Cu deficiency;200-300μg·kg^(−1)).Among the climatic zones Wet zone had higher and the Dry zone had lower Cu concentrations.Among the soil orders,histosols had higher and alfisols had lower Cu concentrations.Water sources used for rice cultivation did not determine Cu concentration.Moreover,Cu concentration was positively correlated with soil pH.As most of the soil samples were deficient in soil exchangeable Cu,spatial maps generated in the current work could be used to develop ACZ and soil order-specific agronomic and management strategies to improve soil Cu fertility status.

Responses of Soil Microbial Community Structure and Diversity to Agricultural Deintensification

Using a scheme of agricultural fields with progressively less intensive management (deintensification), different manage- ment practices in six agroecosystems located near Goldsboro, NC, USA were tested in a large-scale experiment, including two cash-grain cropping systems employing either tillage (CT) or no-tillage (NT), an organic farming system (OR), an integrated cropping system with animals (IN), a successional field (SU), and a plantation woodlot (WO). Microbial phos- pholipid fatty acid (PLFA) profiles and substrate utilization patterns (BIOLOG ECO plates) were measured to examine the effects of deintensification on the structure and diversity of soil microbial communities. Principle component analyses of PLFA and BIOLOG data showed that the microbial community structure diverged among the soils of the six systems. Lower microbial diversity was found in lowly managed ecosystem than that in intensive and moderately managed agro- ecosystems, and both fungal contribution to the total identified PLFAs and the ratio of microbial biomass C/N increased along with agricultural deintensification. Significantly higher ratios of C/N (P < 0.05) were found in the WO and SU systems, and for fungal/bacterial PLFAs in the WO system (P < 0.05). There were also significant decreases (P < 0.05) along with agricultural deintensification for contributions of total bacterial and gram positive (G+) bacterial PLFAs. Agricultural deintensification could facilitate the development of microbial communities that favor soil fungi over bacteria.

Clinacanthus nutans:a review of the medicinal uses,pharmacology and phytochemistry

Clinacanthus nutans Lindau is known as snake grass belonging to the Acanlhaceae family.This plant has diverse and potential medicinal uses in traditional herbal medicine for treating skin rashes,insects and snake bites,lesions caused by herpes simplex virus,diabetes,and gout in Malaysia.Indonesia.Thailand and China.Phylochemieal investigations documented the varied contents of bioaclive compounds from litis plant namely flavonoids,glycosides,glycoglyeerolipids.cerebrosides and monoacylmonogalatosylglycerol.The pharmacological experiment proved that various types of extracts and pure compounds from this species exhibited a broad range of biological properties such as anti-inflammatory,antiviral,antioxidant,and anti-diabetic activities.The lindings of toxicity study showed that extracts from this plant did not show any toxicity thus it can be used as strong therapeutic agents for specific diseased conditions.However,further experiments on chemical components and their mode of action showing biological activities are required to elucidate the complete phytochemical profile and assess to confirm their suitability tor future drugs.This review summarizes the medicinal uses,phytochemistry and pharmacology of this plant in order to explore its therapeutic potential and gaps necessitating for prospected research work.

Biodegradability of soil water soluble organic carbon extracted from seven different soils

Water soluble organic carbon （WSOC） is considered the most mobile and reactive soil carbon source and its characterization is an important issue for soil ecology study. A biodegradability test was set up to study WSOC extracted from 7 soils differently managed. WSOC was extracted from soil with water （soil/water ratio of 1：2, W/V） for 30 min, and then tested for biodegradability by a liquid state respirometric test. Result obtained confirmed the finding that WSOC biodegradability depended on the both land use and management practice. These results suggested the biodegradability test as suitable method to characterize WSOC, and provided useful information to soil fertility.