Cultivated Soils Research Articles

Degradation Rate/Vulnerability Potential and Fertility Status of Luvisols in the Mandara Mountains (Far-North Cameroon).

Soil degradation emerges as one of the major problems in the locality of Sir in the Mandara Mountains, Far-North Cameroon. Inappropriate agricultural techniques resulting in land use change affect soil functions and seriously harm forest ecosystems. This study was conducted to analyse the current character of soils and access their degradation and their level of fertility. Twenty soil samples were taken at 15 cm depth. This includes ten in the plot under forest reserve and ten others in the plot under cultivation. Cultivation is responsible for the increase in bulk density (BD) (1.59 to 2.23 g/cm3), Mg (4.76 to 6.40 cmol·kg-1), Ca (10.44 to 11.26 cmol·kg-1), P (7.93 to 9.93 g/kg), and Mg/K (2.28 to 5.84) and decrease in CEC (38 0.15 to 31.46 cmol·kg-1), OM (2.76 to 1.08%), OC (1.66 to 0.62%), total nitrogen (0.08 to 0.05%), K (4.59 to 1.15 cmol·kg-1), Na (1.32 to 0.91 cmol·kg-1), C/N (25.69 to 13.86), and Ca/Mg (2.32 to 1.89). This variability in physicochemical properties reflects progressive soil degradation. Cultivated soils are subject to severe degradation or potential vulnerability (SDR/Vp = 4/2) due to texture, organic carbon, soil aggregate stability, sealing index, and total nitrogen. On the other hand, soils under forest reserve are subject to severe degradation or vulnerability due to the total nitrogen and sodium absorption ratio. The soils of the study area are subject to severe and extreme potential degradation or vulnerability due to BD, respectively, under forest reserve and cultivation. Two classes of fertility were identified: class II (plots under forest reserve) having a good level of fertility, characterized by good physical properties and severe limitations in nitrogen and phosphorus and class IV (cultivated plots) with a low level of fertility due to severe limitations in organic matter, phosphorus, and poor physical characteristics. The best indicator of the good quality of the luvisols of Sir is the pH, while the bulk density is an indicator of severe to very extreme degradation or high to very high vulnerability. The application of organic and mineral amendments is essential for raising the organic matter and nitrogen and phosphorus contents in these soils.

Zinc oxide application alleviates arsenic-mediated oxidative stress via physio-biochemical mechanism in rice.

Arsenic (As) pollution in cultivated soils poses a significant risk to the sustainable growth of agriculture and jeopardizes food security. However, the mechanisms underlying how zinc (Zn) regulates the toxic effects induced by As in plants remain poorly understood. Hence, this study aimed to explore the potential of ZnO as an effective and environmentally friendly amendment to alleviate As toxicity in rice, thereby addressing the significant risk posed by As pollution in cultivated soils. Through a hydroponic experiment, the study assessed the mitigating effects of different ZnO dosages (Zn5, 5mg L-1; Zn15, 15mg L-1; Zn30, 30mg L-1) on rice seedlings exposed to varying levels of As stress (As0, 0µM L-1; As25, 25µM L-1). The findings of the study demonstrate significant improvements in plant height and biomass (shoot and root), with a notable increase of 16-40% observed in the Zn15 treatment, and an even more substantial enhancement of 29-53% observed in the Zn30 treatment under As stress, compared to respective control treatment. Furthermore, in the Zn30 treatment, the shoot and root As contents substantially reduced by 47% and 63%, respectively, relative to the control treatment. The elevated Zn contents in shoots and roots enhanced antioxidant enzyme activities (POD, SOD, and CAT), and decreased MDA contents (13-25%) and H2O2 contents (11-27%), indicating the mitigation of oxidative stress. Moreover, the expression of antioxidant-related genes, OsSOD-Cu/Zn, OsCATA, OsCATB, and OsAPX1 was reduced when rice seedlings were exposed to As stress and significantly enhanced after Zn addition. Overall, the research suggests that ZnO application could effectively mitigate As uptake and toxicity in rice plants cultivated in As-contaminated soils, offering potential solutions for sustainable agriculture and food security.

Phyto-parasitic nematodes of bell pepper plant and farm soil in Abua, Rivers State, Nigeria

Bell pepper farming significantly contributes to economic development in Abua. However, phyto-parasitic nematodes are endemic in the area and affect quality of crop yield. Hence, this study was undertaken to investigate the dynamics of occurrence of nematodes in bell pepper roots and soil samples of the farms in Abua. Roots and soil from the root rhizosphere were simultaneously collected at 0-20 cm depth using an improvised soil auger and knife. Modified sieve plate technique was employed for nematode detection and a pictorial key was used for nematode identification at the genera level. An overall nematode abundance of 746 nematodes in the soil around the root region and 216 nematodes in the root tissues of the bell peppers were recorded. Gracilachus species (10.6 %) was more prevalent in the soil, and Meloidogyne species (35.2 %) exhibited the highest population in roots. The study found that Abua's cultivated soil is susceptible to nematode infestation, limiting crop performance. The nematodes showcased root burrowing which is an inherent pattern for survival. The result on root nematodes across the five bell farms surveyed was not significant (p > 0.05). The result opined that farmers in Abua, Rivers State, should understand the role of the soil nematodes and implement soil improvement strategies for improved crop performance and rural economic development.

Crop plants transport irregularly shaped mineral particles from root to shoot: Tracking and quantifying

Mineral particles, ubiquitous in soils, influence crop plant growth by carrying nutrients and pollutants. While the uptake of dissolved mineral nutrients is well-established, the direct incorporation of irregular mineral particles into plants remains unclear. This study investigated the uptake and transport of kaolin particles, representative of minerals, by wheat and lettuce seedlings using hydroponic and soil cultures. Covalent labeling and advanced microscopy revealed that kaolin enters root steles at lateral root emergence sites, followed by transport to shoots. Fluorescent dyes and lanthanum (La)-labeled kaolin particles demonstrated that wheat surpassed lettuce in kaolin uptake in hydroponics, but both plants showed similar levels of particles in the shoots. Translocation factors (TFs) for kaolin were significantly higher in soil (0.089 for wheat, 0.039 for lettuce) compared to hydroponics (0.001 for wheat, 0.003 for lettuce). These findings provide compelling evidence for the direct uptake and transport of kaolin particles in crop plants. This opens new avenues for research on the interactions between plant and mineral particles, including other colloidal particles, in terrestrial ecosystems.

Alterations in the Nutrient Status of Soil and Enzymatic Activity of Finger Millet Cultivated Soil Accompanying to Nano Urea Application

An experiment was conducted at the Zonal Agricultural Research Station, Gandhi Krishi Vigyan Kendra, University of Agricultural Sciences, Bangalore, with the aim of assessing the impact of nano nitrogen on growth, yield, nutrient uptake, nitrogen use efficiency and enzymatic activity in finger millet cultivation. Among different treatments, application of 75% RDN + seed treatment with nano urea + foliar spray of nano urea at 30 and 50 DAS showed significant improvements in various growth and yield parameters of finger millet. At 90 DAS, it resulted in a remarkable increase in the number of leaves hill-1 (36.73), leaf area (982.90 cm2 hill-1) and leaf area index (3.28). The treatment also led to enhanced growth indices viz., absolute growth rate of 0.74 g day-1, a relative growth rate of 0.029 g g-1 day-1 and a crop growth rate of 24.80 g m2 day-1 during 60-90 DAS period. Significantly, it boosted the grain yield of 3,397 kg ha-1 for finger millet over control. Notably, this treatment exhibited higher NPK (86.56, 25.93 and 55.36 kg ha-1 respectively) uptake at harvest. It also demonstrated superior agronomic efficiency, internal utilization efficiency and nutrient increment efficiency of nitrogen (52.57, 39.24 and 1.40 kg kg-1 respectively). These findings underscore the potential of nano nitrogen in enhancing finger millet growth, increasing yield, optimizing nutrient uptake and improving nitrogen use efficiency in finger millet cultivation.

The influence of previous crops and tillage on available moisture reserves of chernozem typical for growing spring barley

The unstable yield of agricultural crops arises due to insufficient soil moisture supply at crucial moments of plant emergence and growth, complicating agriculture and exposing it to the risk of crop losses. The purpose of the study is to determine the impact of the soil tillage system and previous crops on the productivity of spring barley plants. This was a long-term stationary experiment (2021-2023) with the application of statistical data processing. The influence of four previous crops was investigated – grain maize (control), soybeans, winter rapeseed, and sunflower – and three main soil tillage methods. It is established that the highest significant moisture reserves in the 0-100 cm soil layer at the sowing period were formed when spring barley was placed after soybeans, exceeding the control variant (grain maize) by 3.2 mm in 2021, 3.6 mm in 2022, and 3.4 mm in 2023, and after winter rapeseed by 8.5 mm, 6 mm, and 5.7 mm, respectively, over the years. The use of shallow no-till cultivation provided an advantage over the control (ploughing) in all years of observation: by 2.2 mm in 2021, 1.8 mm in 2022, and 8.8 mm in 2023. During the sowing period of the studied crop, the control surpassed only surface no-till cultivation by 2.7 mm in 2022. The optimal option should be considered the combination of soybeans as a previous crop with shallow no-till soil cultivation at 14-16 cm, which ensured moisture reserves during the earing period of the crop in 2021 – 75.1 mm, in 2022 – 93.2 mm, and in 2023 – 92.2 mm, and at the time of harvest, these indicators were 60.7 mm, 67.3 mm, and 60.0 mm, respectively. The grain yield of spring barley under this option was the highest in the experiment, averaging 7.26 t/ha, which is 27.3% higher than the control. The results of the study can be used to realise the genetic potential of spring barley plants to form stable productivity

Assessing the effect of soil cultivation methods and genotypes on crop yield components, yield and soil properties in wheat (Triticum aestivum L.) and Rice (Oryza sativa L.) cropping system

BackgroundThe rice-wheat cropping system is the prevailing agricultural method in the North-Western states of India, namely in the Indo-Gangetic plains. The practice of open burning of rice residue is frequently employed for expedient land preparation, but it has significant adverse impacts on both the environment and human health. These include the emission of greenhouse gases, loss of nutrients, elevated concentrations of particulate matter (PM), and disruption of the biological cycle. This research aims to investigate the implementation of effective management strategies in the rice-wheat cropping system, namely via the use of tillage-based crop cultivation techniques, stubble retention, and integration approaches. The objective is to enhance soil health features in order to augment crop yield and improve its attributes.ResultsThe research was carried out using a split plot experimental design, consisting of three replications. The main plot consisted of four different cultivation methods, while the subplot included three genotypes of both rice and wheat. The research demonstrates the enhanced efficacy of residue application is significantly augmenting soil nutrient concentrations compared to standard tillage practices (P < 0.05). This was accomplished by an analysis of soil nutrient levels, namely nitrogen (N), phosphorus (P), potassium (K), and organic carbon (OC), at a depth of 0–15 cm. The implementation of natural farming, zero tillage, and reduced tillage practices resulted in decreases in rice grain yields of 34.0%, 16.1%, and 10.8%, respectively, as compared to conventional tillage methods. Similarly, the implementation of natural farming, zero tillage, and reduced tillage resulted in reductions in wheat grain yields of 59.4%, 10.9%, and 4.6% respectively, in comparison to conventional tillage practices.ConclusionRegarding the individual crop genotypes investigated, it was continuously observed that Him Palam Lal Dhan 1 and HPW 368 displayed considerably greater grain yields for both rice and wheat during the two-year experimental period. Furthermore, when considering different cultivation methods, conventional tillage emerged as the most effective approach for obtaining higher productivity in both rice and wheat. Additionally, Him Palam Lal Dhan 1 and HPW 368 exhibited superior performance in terms of various crucial yield components for rice (such as panicle density, grains per panicle, panicle weight, and test weight) and wheat (including effective tiller density, grains per spike, spike weight, and 1000-grain weight).

Responses of shallot to ameliorant and actinobacteria applications in water-saturated system on tidal land

Tidal areas are believed as future land for many commodities in Indonesia. Here, shallot growing was evaluated on tidal land supplemented with soil conditioners. The research aimed to evaluate the adaptive response of shallot varieties for growing on tidal land with a water-saturated system indicating Fe and Al stress by applying soil ameliorant and actinobacterial. The study used a completely randomized factorial design with three replications. The first factor was shallot variety (Bima Brebes, Batu Ijo, and SS Sakato) and the second factor was soil conditioners (no ameliorant, actinobacteria, ameliorant+actinobacteria, and actinobacteria+ameliorant+dolomite). Bima Brebes and Batu Ijo cultivars had the highest growth percentage, age at shoot emergence, plant height, and number of leaves, while the SS Sakato variety had the slowest growth. Shallot production variable had a significant interaction with soil conditioners. Bima Brebes variety demonstrated high suitability for a water-saturated system in tidal land, and actinobacteria+ameliorant+dolomite was a more promising conditioner than other treatments. Keywords: pyrite, saturated soil culture, tidal swamps, growth, yield, marginal land.

Inversion of coastal cultivated soil salt content based on multi-source spectra and environmental variables

Soil salinization seriously hinders the development of efficient ecological agriculture in coastal areas. The use of Landsat, Sentinel series and hyperspectral data is an ideal way for assessing soil salinity indicators. However, environmental data (e.g. climate, terrain and parent material) are important factors for estimating such indicators. It is necessary to find the advantages and limitations of a combination of satellite images, hyperspectral data and environmental variables (ENVI) for assessing soil salinity accurately. Various data or their combinations ([I] remote sensing [RS], i.e. bands and salinity indices of Landsat 9 and Sentinel 2; [II] ENVI, including soil attributes, climate and topography; and [III] RS + ENVI) were used to construct the salinity inversion model using random forest (RF) and extremely randomized trees (ERT) for cultivated areas in the coastal plain of Dongtai City, China. The hyperspectral data were also resampled to match the range of the image bands. RF performed better than ERT for all types of analyzed data, and RS + ENVI exhibited the best performance for Sentinel 2 (R2 = 0.86). Compared with the RS data alone, Landsat 9 and Sentinel 2 provided higher salinity simulations (41% and 126%, respectively) after combination with ENVI, and salinity mapping was closer to the actual soil salinity measurements. The variables of slope, salinity index (SIT), difference index and SIT had the highest contribution in Landsat 9, Sentinel 2 and resampled hyperspectrum based on Landsat 9 and Sentinel 2, respectively. In conclusion, RS + ENVI based on Sentinel 2 data is the recommended approach for monitoring the salt content of coastal cultivated soil.

Features of the application of soil cultivation methods in the cultivation of soybeans in the forest-steppe zone

Features of the application of soil cultivation methods in the cultivation of soybeans in the forest-steppe zone

Characterizing River Manafwa Floodplain and Adjacent Soils

The objective of this study was to characterise Manafwa River floodplain and adjacent soils. Soil samples were collected from 0 - 20 cm depth in fallowed and cultivated Manafwa floodplain soils for laboratory analysis. Treatments included upland (control), floodplains fallowed for a year, floodplains fallowed for over a year, cultivated floodplains within 5 m and 50 m away from the river banks. Each treatment was replicated three times (3 blocks), and samples collected were analysed for K, Na, available P, total N, exchangeable acidity, pH, organic matter, moisture content, sand, silt, and clay. The soil sampling results were subjected to statistical Analysis of Variance (ANOVA) using Randomised Complete Block Design (RCBD), and the difference between treatment means were dictated using F-, student’s t and F-LSD/pairwise comparison tests. There was statistically no significant (p &gt; 0.05) difference among different floodplains and uplands studied. Upland soils posted 71.67% for the highest pH and 0.09%, 0.87%, 9.74 ppm, 2.23 ppm and 7.264% for the lowest available N, organic matter, Phosphorous, Sodium and Moisture Content, respectively. Cultivated floodplain soil posted highest total P at 29.16 ppm and pH at 6.39% while fallowed floodplains lowest pH at 5.34%, highest available N at 0.32%, highest organic matter at 4.02%, highest K at 21.33%, highest Na at 13.93%, highest exchangeable acidity at 2.32 Cmol/Kg, highest clay content at 14.33%, lowest sand composition at 38.00%, highest silt composition at 54.8% and highest Moisture Content of 32.472%. As depicted by soil fertility analysis results, Manafwa River floodplain and adjacent soils have the capacity to accommodate and boost crop production and productivity. Any nutrients lost to leaching could be gained from subsequent fallowing and sustainable soil fertility management, proper drainage, crop rotation, adding organic manure, and cover cropping, among others

Determination of heavy metal concentrations in cultivated soils and prediction of pollution risk ındices using the ANN approach

Determination of heavy metal concentrations in cultivated soils and prediction of pollution risk ındices using the ANN approach

Comparative Study on the Bacterial Community of Cultivated and Uncultivated Rice Field Soils

A study was conducted to determine the changes in bacterial micro flora of soil in relation fallowing (abandonment) in rice fields. Soil samples from two paddy fields at Kumarakom region, southwest part of Kuttanad, Kerala, one field with paddy cultivation and the other fallowed, was subjected to the study. A total of 15 bacterial species, 8 from the cultivated field only, 6 from the fallowed field only and 1 common to both fields were isolated and identified in the study. The bacterial community in the soil of uncultivated field are entirely shifted from field where rice has been cultivated continuously. The persistent occurrence encountered in the cultivated field isolates were Bacillus megaterium, Pseudomonas aeroginosa and Klebsiella oxytoca while that in the abandoned field were of E coli followed by higher incidence of (80%) Enterobacter aerogenes and Citrobacter freundii. Under rice cultivation, soil pH, EC and bacterial density were generally higher than that in uncultivated soils while organic carbon in the soil was consistently lower than that in uncultivated soils. The study reveals the importance of bacteria in maintaining the health of a habitat and confirm that soil quality deteriorates over long-term fallowing.

Design and Fabrication of Solar Power Tiller

The present research focuses on the development of a solar-powered rotary tiller designed for primary and secondary soil cultivation. It explores the disparities between portable weeders and power tillers available in the Indian market. Various approaches to weed removal in crops are also examined. This study demonstrates that the majority of Indian farmers, particularly those with small-scale operations, can only afford portable weeders. Soil tillers and weeders are among the many agricultural mechanizations aimed at enhancing soil cultivation and weed management, particularly given that most farmers own small parcels of land. These tools notably reduce manual labor and are largely self-guided. The project operates on solar panels, utilizing their energy to power the machine, which operates the cutter or tiller. This innovation significantly saves time and expenses in field tasks, proving highly efficient for both tilling and weeding duties. Additionally, proposing the creation of high-capacity, energy-saving, adaptable machines, and integrated equipment aims to enhance labor efficiency, lower operational costs, improve punctuality, and render them suitable for customized leasing. Key Words: solar, power, tiller, weeder, farming, soil

Sulfur dynamics in saline sodic soils: The role of paddy cultivation and organic amendments

The phenomenon of sulfur (S) deficiency in Chinese soil is becoming increasingly severe, especially in the northeastern saline-sodic wasteland (WL). To determine the bioavailability of S in long-term cultivated paddy soil with or without organic amendment addition, the long-term field experiment site was established and incubation experiments were conducted. Compared to WL, soil properties have been continuously improved during the 15-year paddy field (PF) cultivation, ultimately enhancing the content of soil organic carbon (by 242.62 %), total nitrogen (by 126.49 %) and alkali-hydrolyzed nitrogen (by 28.07 %). Additionally, soil salinization has been decreasing, and the stock of total sulfur (TS) and available sulfur (AS) in the 0–60 cm soil layer have increased by 32.09 % and 293.52 % respectively. In contrast, organically-amended soil (OA) manifested superior TS and AS levels vs. PF. Additionally, water-soluble sulfur (WSS) was markedly elevated, registering post-annual increments of 227.31 % and 268.36 % in PF and OA, respectively, relative to WL. The key mechanistic impetus for the application of organic amendments was the enhancement of the soil's adsorptive and mineralization capabilities. As observed in our soil culture experiment, the maximum adsorption of sulfate ions and the cumulative mineralization of sulfur in the soil follow the pattern of OA > PF > WL. The Partial Least Squares Path Model (PLSPM) corroborated that both organic amendments and years of cultivation indirectly influenced total inorganic sulfur fractions. This influence is primarily mediated via structural soil enhancements and salinization amelioration, thereby elevating available quantities of sulfur in saline-sodic soil environments. In conclusion, from the perspective of soil sulfur biogeochemical cycling, we have confirmed that reclaiming saline-sodic wasteland for paddy field could be a beneficial and sustainable approach for soil management. These findings of this study can also provide an in-depth understanding of the bioavailability and influencing mechanism of sulfur in long-term saline-sodic paddy fields.

Evaluating the agronomic efficiency of alternative phosphorus sources applied in Brazilian tropical soils

Understanding the efficacy of alternative phosphorus (P) sources in tropical soils is crucial for sustainable farming, addressing resource constraints, mitigating environmental impact, improving crop productivity, and optimizing soil-specific solutions. While the topic holds great importance, current literature falls short in providing thorough, region-specific studies on the effectiveness of alternative P sources in Brazilian tropical soils for maize cultivation. Our aim was to assess the agronomic efficiency of alternative P sources concerning maize crop (Zea mays L.) attributes, including height, shoot dry weight, stem diameter, and nutrient accumulation, across five Brazilian tropical soils. In greenhouse conditions, we carried out a randomized complete block design, investigating two factors (soil type and P sources), evaluating five tropical soils with varying clay contents and three alternative sources of P, as well as a commercial source and a control group. We evaluated maize crop attributes such as height, dry weight biomass, and nutrient accumulation, P availability and agronomic efficiency. Our results showed that, although triple superphosphate (TSP) exhibited greater values than alternative P sources (precipitated phosphorus 1, precipitated phosphorus 2 and reactive phosphate) for maize crop attributes (e.g., height, stem diameter, shoot dry weight and phosphorus, nitrogen, sulfur, calcium and magnesium accumulation). For instance, PP1 source increased nutrient accumulation for phosphorus (P), nitrogen (N), and sulfur (S) by 37.05% and 75.98% (P), 34.39% and 72.07% (N), and 41.94% and 72.69% (S) in comparison to PP2 and RP, respectively. Additionally, PP1 substantially increased P availability in soils with high clay contents 15 days after planting (DAP), showing increases of 61.90%, 99.04%, and 38.09% greater than PP2, RP, and TSP. For Ca and Mg accumulation, the highest values were found in the COxisol2 soil when PP2 was applied, Ca = 44.31% and 69.48%; and Mg = 46.23 and 75.79%, greater than PP1 and RP, respectively. Finally, the highest values for relative agronomic efficiency were observed in COxisol2 when PP1 was applied. The precipitated phosphate sources (PP1 and PP2) exhibited a similar behavior to that of the commercial source (TSP), suggesting their potential use to reduce reliance on TSP fertilization, especially in soils with low clay contents. This study emphasized strategies for soil P management, aimed at assisting farmers in enhancing maize crop productivity while simultaneously addressing the effectiveness of alternative P sources of reduced costs.

Effects of lateral spacings and irrigation water quality on plant growth and yield parameters of onion in the semi‐arid region of India

AbstractField experiments were conducted to investigate an appropriate saline water management strategy to enhance the yield and irrigation water use efficiency (IWUE) of drip‐irrigated onion. The effects on soil water–salt dynamics, growth parameters, IWUE and yield were assessed under different lateral spacings and irrigation treatments. The different treatments comprised two lateral spacings (45 and 60 cm) and four irrigation treatments (canal water, C; conjunctive use of canal and saline water in a 1:1 ratio, C1S1; in a 1:2 ratio, C1S2; and saline water, S). The results show that soil moisture content decreased vertically downwards and radially outwards in all treatments, whereas soil salinity increased and decreased with increasing radial distance and soil depth, respectively, throughout the soil profile irrespective of the lateral spacing and irrigation treatments. The maximum yield and IWUE were observed at 45‐cm lateral spacing for treatment C, followed by C1S1, C1S2 and S. It was concluded that the C1S1 treatment can be employed successfully for onion cultivation in sandy loam soil without any significant reduction in yield. The present study highlights the significance of irrigation treatments and lateral spacing for maximum production, which may be used as a baseline/guideline to increase the income of onion growers/farmers in semi‐arid regions.

The sacred soils of ancient India

Soils at 57 ancient Hindu temples in India are documented from field profiles as a basis for understanding livelihoods of the five cults of Puranic (Smarta) Hinduism during the first millennium CE. Similar soils were found at different temples of the same deity, but different kinds of soils at temples of different deities. Temples of Ganesha and Hanuman, for example, are alluvial Entisols and Vertisols, the principal cultivable soils of India. Temples of Vishnu and Lakshmi are well drained Alfisols and Aridisols suitable for grazing, housing and markets. Different soils supported different livelihoods, social classes and cults, such as servant (shudra) class for farmers Ganesha and Hanuman, and herder-merchant (vaishya) class for Vishnu and Lakshmi. This result matches accounts in the Matsya Purana (250–500 CE) specifying dark organic soils for shudras and red soil for vaishyas. Puranic Smarta polytheism may reflect amalgamation of different tribal traditions during expansion of Gupta and other Hindu empires.

Bacterial Community Structure Responds to Soil Management in the Rhizosphere of Vine Grape Vineyards.

The microbial communities of the rhizospheres of vineyards have been subject to a considerable body of research, but it is still unclear how the applied soil cultivation methods are able to change the structure, composition, and level of diversity of their communities. Rhizosphere samples were collected from three neighbouring vineyards with the same time of planting and planting material (rootstock: Teleki 5C; Vitis vinifera: Müller Thurgau). Our objective was to examine the diversity occurring in bacterial community structures in vineyards that differ only in the methods of tillage procedure applied, namely intensive (INT), extensive (EXT), and abandoned (AB). For that we took samples from two depths (10-30 cm (shallow = S) and 30-50 cm (deep = D) of the grape rhizosphere in each vineyard and the laboratory and immediately prepared the slices of the roots for DNA-based analysis of the bacterial communities. Bacterial community structure was assessed by means of PCR-DGGE analysis carried out on the v3 region of 16S rRNA gene. Based on the band composition of the DGGE profiles thus obtained, the diversity of the microbial communities was evaluated and determined by the Shannon-Weaver index (H'). Between the AB and EXT vineyards at the S depth, the similarity of the community structure was 55%; however, the similarity of the D samples was more than 80%, while the difference between the INT samples and the other two was also higher than 80%. Based on our results, we can conclude that intensive cultivation strongly affects the structure and diversity of the bacterial community.

Integrative physiology and transcriptome reveal salt-tolerance differences between two licorice species: Ion transport, Casparian strip formation and flavonoids biosynthesis

BackgroundGlycyrrhiza inflata Bat. and Glycyrrhiza uralensis Fisch. are both original plants of ‘Gan Cao’ in the Chinese Pharmacopoeia, and G. uralensis is currently the mainstream variety of licorice and has a long history of use in traditional Chinese medicine. Both of these species have shown some degree of tolerance to salinity, G. inflata exhibits higher salt tolerance than G. uralensis and can grow on saline meadow soils and crusty saline soils. However, the regulatory mechanism responsible for the differences in salt tolerance between different licorice species is unclear. Due to land area-related limitations, the excavation and cultivation of licorice varieties in saline-alkaline areas that both exhibit tolerance to salt and contain highly efficient active substances are needed. The systematic identification of the key genes and pathways associated with the differences in salt tolerance between these two licorice species will be beneficial for cultivating high-quality salt-tolerant licorice G. uralensis plant varieties and for the long-term development of the licorice industry. In this research, the differences in growth response indicators, ion accumulation, and transcription expression between the two licorice species were analyzed.ResultsThis research included a comprehensive comparison of growth response indicators, including biomass, malondialdehyde (MDA) levels, and total flavonoids content, between two distinct licorice species and an analysis of their ion content and transcriptome expression. In contrast to the result found for G. uralensis, the salt treatment of G. inflata ensured the stable accumulation of biomass and total flavonoids at 0.5 d, 15 d, and 30 d and the restriction of Na+ to the roots while allowing for more K+ and Ca2+ accumulation. Notably, despite the increase in the Na+ concentration in the roots, the MDA concentration remained low. Transcriptome analysis revealed that the regulatory effects of growth and ion transport on the two licorice species were strongly correlated with the following pathways and relevant DEGs: the TCA cycle, the pentose phosphate pathway, and the photosynthetic carbon fixation pathway involved in carbon metabolism; Casparian strip formation (lignin oxidation and translocation, suberin formation) in response to Na+; K+ and Ca2+ translocation, organic solute synthesis (arginine, polyamines, GABA) in response to osmotic stresses; and the biosynthesis of the nonenzymatic antioxidants carotenoids and flavonoids in response to antioxidant stress. Furthermore, the differential expression of the DEGs related to ABA signaling in hormone transduction and the regulation of transcription factors such as the HSF and GRAS families may be associated with the remarkable salt tolerance of G. inflata.ConclusionCompared with G. uralensis, G. inflata exhibits greater salt tolerance, which is primarily attributable to factors related to carbon metabolism, endodermal barrier formation and development, K+ and Ca2+ transport, biosynthesis of carotenoids and flavonoids, and regulation of signal transduction pathways and salt-responsive transcription factors. The formation of the Casparian strip, especially the transport and oxidation of lignin precursors, is likely the primary reason for the markedly higher amount of Na+ in the roots of G. inflata than in those of G. uralensis. The tendency of G. inflata to maintain low MDA levels in its roots under such conditions is closely related to the biosynthesis of flavonoids and carotenoids and the maintenance of the osmotic balance in roots by the absorption of more K+ and Ca2+ to meet growth needs. These findings may provide new insights for developing and cultivating G. uralensis plant species selected for cultivation in saline environments or soils managed through agronomic practices that involve the use of water with a high salt content.