Relative Efficiency Index Research Articles

Quantitative Analysis of the Evolution of Production–Living–Ecological Space in Traditional Villages: A Comparative Study of Rural Areas in Tibet

Since the introduction of the rural revitalization strategy by the 19th National Congress of the Communist Party of China in 2017, there have been significant transformations in the production–living–ecological space (PLES) within villages. Evaluating and enhancing villages’ PLES are crucial for fostering sustainable development. Therefore, this study utilized a multi-scale environmental assessment model and mathematical approach to conduct horizontal and vertical nested correlation analyses of indicators at different levels through a path analysis, a Spearman correlation analysis, a variance analysis, the entropy weight method, data simulation, and other methods to establish a “three-dimensional” comprehensive evaluation system for traditional village PLES. The findings indicate the following: (1) The ecological space of traditional villages in Tibet significantly impacts the overall environment of the PLES, with the components’ impact ranked as follows: ecological space > production space > living space. Furthermore, industry and tourism resources show a significant positive correlation with traditional villages’ PLES; (2) There are no significant differences in natural environmental factors, such as air relative humidity, temperature, humidity index, and wind efficiency index among traditional villages in neighboring cities in Tibet. However, they all possess profound ecological and cultural heritage; (3) There are notable disparities in living space between traditional villages in Lhasa and Nyingchi, indicating unbalanced development. It is evident that traditional village construction should not only focus on the development of certain PLES but also pay attention to the balanced development of the overall spatial environment. This study holds great significance for enhancing the living environment of traditional villages in Tibet and promoting sustainable development through protection efforts in these villages.

Integrated organic and mineral fertilizer strategies for achieving sustainable maize yield and soil quality in dry sub-humid inceptisols

Maize is one of the important cereal crops grown in rainfed regions of northwestern Himalayas, however, persistent use of chemical fertilizers coupled with poor soil nutrients and water holding capacity due to coarse textured soils poses serious threat to sustaining maize yield and soil health. To address these bottlenecks, a long-term experiment with application of organic manures and mineral fertilizer provides insights to quantify changes in soil organic carbon (SOC), crop yield and rain water use efficiency (RWUE) in rainfed area having low water use efficiency. A twelve years field experiment was conducted under dry sub-humid Inceptisols in northern India to study the potential impacts of organic and mineral fertilization on maize (Zea mays L.) productivity, water use efficiency and soil quality. Ten treatments were assessed, involving different nitrogen levels (20, 30, and 40 kg N ha⁻¹) combined with 10 tha⁻¹ year⁻¹ of farmyard manure (FYM), in-situ green manure from sunhemp, and the incorporation of Leucaena leucocephala leaves at 5 tha⁻¹ year⁻¹, including an unfertilized control. Maize yield increased linearly with increasing nitrogen application rates. The combination of FYM @ 10t ha−1 and 40 kg N ha−1(T4) yielded the highest maize production. Manure addition improved soil organic carbon (SOC) and major soil nutrients (N, P and K) while unfertilized control showed decline in soil nutrients compared to their initial values. Compared with control, incorporation of 10 t ha−1 FYM increased SOC by 1.3, 1.41, 1.44 times at application rate of 20, 30, 40 kg N ha−1, respectively. Application of N@40 kg ha−1 + 10t FYM ha−1 showed highest rain water use efficiency (RWUE) and relative production efficiency index (RPEI) (2.74 kg ha−1 mm−1 and 82, respectively) and the lowest rank sum of 6. Highly significant positive relationship existed between RPEI and RWUE, RPEI and sustainability yield index (SYI), RWUE and SYI indicated the superiority of FYM in combination with mineral fertilizer. Regression models, correlating yield with monthly rainfall and crop growing periods, indicated that the integration of FYM (10 tha⁻¹) with 40 kg N ha⁻¹ was most effective in achieving the highest relative soil quality index (RSQI) of 76 and the greatest sustainability yield index (SYI) of 49.3%. Based on results, we recommend balanced fertilization (N@40 kg ha−1 +10t FYM ha−1) which is easily manageable by farmers as the optimal strategy for improving soil quality and achieving sustainable maize productivity in nutrient depleted Inceptisols of northern India.

Combined application of humic substances and PGPR inoculated and co-inoculated in plants of Phaseolus lunatus (L.) and Leucaena leucocephala (Lam.) de Wit

The objective of this research was to evaluate the effect of inoculation and co-inoculation of rhizobia and Azospirillum brasilense combined with humic substances (HS) in growth promotion of Phaseolus lunatus (lima bean) and Leucaena leucocephala (leucaena). For this, experiments in a greenhouse with the cultivation of each plant species were carried out. A randomized complete block experimental design with five repetitions was followed. Plant seeds were sown and then inoculated with rhizobia and co-inoculated with A. brasilense. Subsequently, HS were added at the dose recommended by the manufacturer. In the experiments with both plants, control treatments with the addition of nitrogen (N) with or without HS were used. After 45 days, the shoot dry mass (SDM), root dry mass (RDM), shoot-accumulated N (Nac) and relative efficiency index (REI) were determined. In addition, the mass of dry nodules (MDN) in the lima bean plants and the number of nodules (NN) in leucaena plants were determined. The results showed that in the lima bean and leucaena plants there was a greater increase in SDM, RDM and Nac in treatments that received HS and co-inoculation with rhizobia and A. brasilense than in treatments that were inoculated only with rhizobia and HS and in treatments that received N and HS compared to addition of N and isolated inoculation of rhizobia. The combined application of HS and rhizobia in co-inoculation with A. brasilense had a greater effect on the increase of MDN in lima bean and NN in leucaena, than in treatments where only rhizobia with HS were added. These results indicate the existence of potential interaction of the use of HS with the co-inoculation of rhizobia and A. brasilense, showing promise for the production of sustainable agricultural crops.

Arbuscular mycorrhizal fungi on the development and copper content in corn and sorghum plants.

The concentration of copper in the soil increased with the intensification of agricultural activities, mainly in grape production areas and orchards as a result of the application of pesticides. Arbuscular mycorrhizal fungi make up the microbial biomass of the soil and appear as an alternative to be researched for the development of plants in an environment contaminated with copper. The purpose of this pot study was to analyze the influence of arbuscular mycorrhizal fungi on the development and content of copper in corn and sorghum plants. Soil treatments were: without inoculum (control) and two arbuscular mycorrhizal (Acaulospora scrobiculata and Rhizoglomus clarum) and five doses of copper (0, 100, 200, 300, and 400 mg Cu kg-1 soil); with seven repetitions. Plant height, stem diameter, number of tillers, root volume, shoot and root dry weight yields, shoot, root and grain Cu concentrations, pseudo-total soil Cu, percentage of mycorrhizal colonization and relative mycorrhizal efficiency index in reducing Cu concentration in root and shoot of corn and sorgum were evaluated. Morphological parameters of sorghum and corn were reduced with at high Cu doses in the soil, and the inoculation with Acaulospora scrobiculata and Rhizoglomus clarum resulted in greater development and lower Cu concentration in the dry mass of the shoot and root parts sorghum and corn plants.

Overall efficiency increment in a pin-fin microchannel heat sink using response surface methodology and Pareto optimization

In modern technology, anticipating the optimal thermal performance in microchannel heat sinks (MCHSs) is a vital response to overheating challenges in high-performance electronic devices. The Response Surface Methodology (RSM) application presents an innovative way of modeling such equipment's behavior. In the current study, an MCHS with pin fins was chosen to examine the Nusselt number (Nu) and pressure drop (ΔP). Using two RSM models and multi-objective optimization, the study tried to discern the optimal values of the responses in the MCHS. The RSM models examined three key parameters: length, installation angle, and the spacing between pin fins. The interactive impacts of independent parameters and their consequent effect on the responses were also explored. The RSM models attained exceptional predictive accuracy, with the determination coefficient values of 0.9946 and 0.9986 for Nu and ΔP, respectively. The working fluid applied in the present work was water with an inlet temperature of 288 K and a Reynolds number of 300. Besides, the constant heat flux of 100 W/cm2 was exposed to the bottom wall of the MCHS. In pursuit of an optimal MCHS design that maximizes Nu while minimizing ΔP, the study employed the relative efficiency index (η) parameter. Considering heat transfer and ΔP in the pin-fin MCHS, the optimal design showed an impressive improvement of about 64.5 % compared to the fin-free heat sink. Moreover, the study provided Pareto optimal points for Nu, ΔP, and η, adding depth to understanding the complex trade-offs within the investigated MCHS.

Arc-curved microchannels engraved on segmented circular heat sink for heat transfer augmentation; ANN-based performance optimization

The proficient management and supervision of thermal conditions in microelectronic equipment are becoming progressively challenging owing to the imposition of heightened heat fluxes. The exploration of recently developed microchannel heat sinks (MCHSs) is currently underway to effectively tackle this matter. Modifying the geometric characteristics of these gadgets has proven to be highly effective in augmenting their comprehensive performance. In the present study, a novel arc-curved microchannels engraved on segmented circular heat sink and introduced configurations comprising of six discrete segments of spiral microchannels. The study focused on examining the influence of individual partitions on the Nusselt number (Nu) and pressure drop (ΔP) of the MCHS. The obtained results demonstrate that all the proposed configurations exhibit considerably higher values of the Nu in comparison to the reference MCHS consisting of 21 rectangular channels. Nevertheless, the notable augmentation in the value of the parameter Nu occurred simultaneously with an escalated ΔP. Hence, the relative efficiency index was employed as a more precise measure for evaluations. All of the designs suggested in this investigation were found to be effective when subjected to volume flow rates surpassing 47.303 ml/min. In an illustrative case, the segmented circular MCHS encompassing 10 spiral microchannels exhibited an enhanced overall efficiency of 25.9 % when operated at a volume flow rate of 66.225 ml/min, as compared to the benchmark design. In addition, artificial neural networks (ANN) were utilized to comprehensively scrutinize the influence of variables and construct a prognostic model to ascertain the overall effectiveness of the MCHS, obviating the necessity for convoluted, time-consuming, and costly experimental procedures and computations. The presentation of the Pareto optimal points effectively portrayed the optimal and unfavorable outcomes under consideration.

Genetic analysis of tolerance to transient waterlogging stress in pigeonpea (Cajanus cajan L. Millspaugh)

Pigeonpea (Cajanus cajan L. Millspaugh) is mainly grown in the rainfed ecosystem during the monsoon season on deep vertisols, and it often faces transient waterlogging problems due to continuous and heavy downpours during early monsoon seasons. Thus, waterlogging has become a significant issue in most of the pigeonpea growing areas of the semi-arid tropics due to heavy rain during the initial crop growth stage, which causes 30 to 40% economic yield loss in India and around the world. Only a few sources of waterlogging tolerant genotypes are available in pigeonpea but are not in the required duration. Hence, the present investigation was carried out to identify waterlogging tolerant pigeonpea genotypes in different durations suitable for different agroecologies of India and to find ideal selection indices as appropriate strategies to identify waterlogging tolerant genotypes. In this study, 162 genotypes were screened under in vitro conditions for 2, 4, 6, and 8 days by submerging seeds. Of these, 33 genotypes could survive for eight days. Further, following a standard screening protocol; these 33 pigeonpea genotypes were screened under pot culture for two years (2020 and 2021). Based on different morpho-physiological parameters and waterlogging tolerant coefficient, genotypes ICP-10397, ICP-7507, ICP-7869, ICP-7148, ICP-4903 ICP-16309, ICP-7375, ICP-6815, ICP-7507, and ICP-6128 were identified as tolerant to transient waterlogging. In addition, this study reports the existence of substantial genetic variation for waterlogging tolerant traits in pigeonpea. Stress indices, such as stress tolerance index) (STI), mean relative performance (MRP) and relative efficiency index (REI) were identified as the ideal selection index. Therefore, identified genotypes are further validated and can be deployed in waterlogging tolerance pigeonpea breeding programs

Indicators for evaluating the resistance of tomato genotypes to low light

ABSTRACT Low light is one of the most important factors limiting tomato (Solanum lycopersicum L.) production. In this experiment, tomato genotypes under low light (winter planting), and adequate light (summer planting) were evaluated in the same greenhouse condition for other environmental conditions where 11 tolerance and susceptibility indices were evaluated in terms of fruit weight per plant produced. Using the rank of each genotype for the calculated indices, the mean rank index was calculated. The highest yield under adequate light was in genotypes “9318,” “9314,” “2216,” “324,” and “5239.” Under low light, genotypes “321,” “9318,” “9314,” “523,” and “324” had the highest fruit yield per plant, respectively. Evaluation of tolerance and sensitivity indices indicated that tolerance indices, geometric mean productivity index, mean relative performance index and relative efficiency index had a positive, significant, correlation with fruit weight per plant in low light and adequate light are the best indicators for selecting genotypes tolerant to low light. Based on these indices, genotypes “9318,” “9314,” “321,” “324,” and “523” had the highest ranks and more tolerance to low light, and might be successfully cultivated in low light areas.

Thermal and hydrodynamic management of a finned-microchannel heat sink applying artificial neural network

Thermal management of microelectronic circuits will be one of the most difficult challenges facing engineering processes in the near future. High operating temperatures in these devices can degrade the reliability of the components and reduce their life. Therefore, effective cooling technologies that can disperse the significant heat load from the surface of microelectronic equipment are required. An appropriate microchannel heat sink (MCHS) system with optimized geometry can be one of the reliable choices. In the current work, an artificial neural network (ANN) is exerted to optimize the geometry of a finned-MCHS. The distance of fins from the inlet in the second row (l), the distance of fins from the side walls in the first and third rows (t), and the angle of hexagons (θ) are the input parameters. According to the obtained results, the ANN model with a coefficient of determination of 0.999 performed well in predicting the Nusselt number (Nu) and pressure drop (ΔP). Among the investigated input parameters, the variations of the parameter of t affected the thermal and hydrodynamic properties of the device noticeably. Besides, the ANN model suggested that when the optimum values of input parameters (i.e., l = 7.636 mm, t = 4 mm, and θ = 140) are used for the hexagonal fins inside a microchannel, the maximum relative efficiency index of 1.491 can be acquired.

Management of heat transfer and hydraulic characteristics of a micro-channel heat sink with various arrangements of rectangular vortex generators utilizing artificial neural network and response surface methodology

It is common to use micro-channel heat sinks (MCHSs) in equipment such as; ICs, transistors, LEDs, and high-power lasers, which generate heat due to the passage of electric current. This heat is often a menace to harm these devices and their internal parts. For this reason, heat rejection in the MCHSs is an endless challenge for researchers. Placing vortex generators (VGs) within the MCHS improves the cooling capacity but incurs a considerable pressure drop. Meanwhile, the shape, geometric dimensions, and arrangement of the VGs significantly affect this heat transfer. In the current study, the placement angle (θ), the longitudinal distance (dl), and the transverse distance (dt) of the VGs were chosen to be altered. The Artificial Neural Networks (ANN) and Response Surface Methodology (RSM) were exerted to study their variation's effect on the Nusselt number (Nu) and pressure drop (ΔP) of an MCHS. The presented data illustrated that the results of the ANN model were closer to the data provided by the numerical simulation. With the coefficient of determination of 0.995 and 0.992 in forecasting the Nu and ΔP, the ANN exhibited better performance than the RSM model. Besides, the ANN model recommended that to acquire the highest relative efficiency index, the optimum values of placement angle, the longitudinal and transverse distances of the VGs should be 60, 0.151 mm, and 0.166 mm, respectively.

Dynamic Cournot Oligopoly Models of the State Promotion of Innovative Electronic Courses in Universities

We built and investigated a two-level dynamic game theoretic model of control of the state promotion of innovative electronic courses in universities based on Cournot oligopoly. A federal state is the Principal, and universities competing a la Cournot are agents. The agents invest in the development of new electronic educative courses that is considered as their innovative investments. The Principal gives subsidies to the agents for the promotion of innovations. The agents play a dynamic game in normal form that results in a Nash equilibrium, and the Principal solves an inverse Stackelberg game (a Germeier game of the type Γ2t). We investigated different types of strategies: (1) uniform strategies for all agents; (2) type-dependent (agent efficiency-dependent) strategies; (3) action-dependent strategies. For a specific form of the model functions we found a solution in explicit form, and in the general case we used a method of qualitatively representative scenarios in simulation modeling. We analyzed the results by means of the individual and collective relative efficiency indices.

PIMA COTTON (GOSSYPIUM BARBADENSE L.) LINES ASSESSMENT FOR DROUGHT TOLERANCE IN UZBEKISTAN

Globally, increasing water and energy demand is expected to reach 6.9 trillion cubic meters by 2030, exceeding 40% of the available water supplies. Climate change and rising temperatures caused water shortages due to lesser and irregular rainfalls, leading to lower production of crops. The research to assess drought tolerance of Pima cotton (Gossypium barbadense. L) lines in Uzbekistan revealed the line, T-450 as the most promising for drought environments. The research, in a randomized complete block design (RCBD) in three replications with a factorial arrangement and two irrigation regimes (non-stress and water stress at the seedling stage), was conducted at the experimental field of the Institute of Genetics and Plant Experimental Biology, District Zangi-Ota, Tashkent Region, Uzbekistan. Nine Pima cotton lines, i.e., Сурхон-14 (control cultivar), Т-1, Т-5440, Т-2006, Т-10, Т-167, Т-5445, Т-450, and Т-663 with diverse agronomic characters, were selected for their potential yield during 2019, 2020, and 2021 cropping seasons under two different environments (optimal and water deficit condition). Drought indices revealed significant differences among lines, except the golden mean (GM). Results in the ranking method indicate that among the drought tolerance indices, mean productivity (MP), geometric mean productivity (GMP), stress tolerance index (STI), mean relative performance (MRP), relative efficiency index (REI), and relative drought index (RDY), show the most suitable indicators because of their high correlation with seed cotton yield. Cluster analysis and three-dimensional plots showed the cotton inbred lines with the highest tolerance to drought under both irrigation conditions. The first three principal components (PCs) explained 67.54% of total variation and the PC1 can be nominated as a potentially stable yield. The biplot diagram based on PCs and drought tolerance indices showed that MP, GMP, STI, MRP, REI, and YI were the best indices for screening the tolerant cotton inbred lines, such as, T-450.

Trichoderma as a growth promoter in Astronium urundeuva (M. Allemão) Engl.

The low growth is one of the biggest problems encountered in the production of native forest seedlings. Fungi of the genus Trichoderma are microorganisms capable of potentialize the plant growth. Thereby, this article aims to evaluate the efficiency of Trichoderma inoculation, as a plant growth promoter of Aroeira seedlings (Astronium urundeuva (M. Allemão) Engl.), in the greenhouse. The isolated ones, at the approximate concentration of conidia at 1 x 109 per colonized gram of rice, were individually mixed with the soil in a homogeneous form in the experiments with and without phosphate fertilization. For the control treatment, sterilized rice without Trichoderma was used. Two experiments were carried out, at 50 and 100 days after the sowing (DAS). Were evaluated the biomass characteristics of the selected crop through the dry mass of aerial part, the root dry mass and the total dry mass, as well as the relative efficiency and quality index of Dickson. The experiment whose received the natural fertilizer phosphate, occurred a variation of 25.4 to 925% in growth promotion, compared to the control treatment. The experiment without fertilizer showed a variation of 26.5 to 425.4% in growth, compared to the control treatment. The results demonstrate the capacity of isolated Trichoderma to promote an initial growth with or without natural fertilize phosphate to Aroeira.

Comparing EQ-5D-3L and EQ-5D-5L in measuring the HRQoL burden of 4 health conditions in China.

EQ-5D-3L has been used in the National Health Services Survey of China since 2008 to monitor population health. The five-level version of EQ-5D was developed, but there lacks evidence to support the use of five-level version of EQ-5D in China. This study was conducted to compare the measurement properties of both the EQ-5D-3L and EQ-5D-5L in quantifying health-related quality of life (HRQoL) burden for 4 different health conditions in China. Participants from China were recruited to complete the 3L and 5L questionnaire via Internet. Quota was set to recruit five groups of individuals, with one group of individuals without any health condition and one group of generalized anxiety disorder (GAD), HIV/AIDS, chronic Hepatitis B (CHB), or depression, respectively. The 3L and 5L were compared in terms of response distributions, percentages of reporting 'no problems', index value distributions, known-group validity and their relative efficiency. In total, 500 individuals completed the online survey, including 140 healthy individuals, 122 individuals with hepatitis B, 107 with depression, 90 individuals with GAD and 101 with HIV/AIDS. 5L also had smoother and less clustered index value distributions. Healthy group showed different response distributions to the four condition groups. The percentage of reporting 'no problems' decreased significantly in the 5L in all domains (P < 0.01), especially in the pain/discomfort dimension (relative difference: 43.10%). Relative efficiency suggested that 5L had a higher absolute discriminatory power than the 3L version between healthy participant and the other 4 condition groups, especially for the HIV/AIDS group when the 3L results was not significant. The 5L version may be preferable to the 3L, as it demonstrated superior performance with respect to higher sensitivity to mild health problems, better relative efficiency and responses and index value distributions.

Disperse-and-Mix: Oil as an 'Entrance Door' of Carbon-Based Fillers to Rubber Composites.

Oil was employed as an ‘entrance door’ for loading rubber with carbon-based fillers of different size and dimensionalities: 1D carbon nanotubes (CNTs), 2D graphene nanoplatelets (GNPs), and 3D graphite. This approach was explored, as a proof of concept, in the preparation of tire tread, where oil is commonly used to reduce the viscosity of the composite mixture. Rubber was loaded with carbon black (CB, always used) and one or more of the above fillers to enhance the thermal and mechanical properties of the composite. The CNT-loaded system showed the best enhancement in mechanical properties, followed by the CNT-GNP one. Rubber loaded with both graphite and GNP showed the best enhancement in thermal conductivity (58%). The overall enhancements in both mechanical and thermal properties of the various systems were analyzed through an overall relative efficiency index in which the total filler concentration in the system is also included. According to this index, the CNT-loaded system is the most efficient one. The oil as an ‘entrance door’ is an easy and effective novel approach for loading fillers that are in the nanoscale and provide high enhancement of properties at low filler concentrations.

Improvement of Phosphorus Use Efficiency in Rice by Adopting Image-Based Phenotyping and Tolerant Indices.

Phosphorus is one of the second most important nutrients for plant growth and development, and its importance has been realised from its role in various chains of reactions leading to better crop dynamics accompanied by optimum yield. However, the injudicious use of phosphorus (P) and non-renewability across the globe severely limit the agricultural production of crops, such as rice. The development of P-efficient cultivar can be achieved by screening genotypes either by destructive or non-destructive approaches. Exploring image-based phenotyping (shoot and root) and tolerant indices in conjunction under low P conditions was the first report, the epicentre of this study. Eighteen genotypes were selected for hydroponic study from the soil-based screening of 68 genotypes to identify the traits through non-destructive (geometric traits by imaging) and destructive (morphology and physiology) techniques. Geometric traits such as minimum enclosing circle, convex hull, and calliper length show promising responses, in addition to morphological and physiological traits. In 28-day-old seedlings, leaves positioned from third to fifth played a crucial role in P mobilisation to different plant parts and maintained plant architecture under P deficient conditions. Besides, a reduction in leaf angle adjustment due to a decline in leaf biomass was observed. Concomitantly, these geometric traits facilitate the evaluation of low P-tolerant rice cultivars at an earlier stage, accompanying several stress indices. Out of which, Mean Productivity Index, Mean Relative Performance, and Relative Efficiency index utilising image-based traits displayed better responses in identifying tolerant genotypes under low P conditions. This study signifies the importance of image-based phenotyping techniques to identify potential donors and improve P use efficiency in modern rice breeding programs.

Relative Treatment Efficiency Index of Eichhornia crassipes in Removing Cd, Pb and Ni from Wastewater

Relative treatment efficiency index (RTEI) is used to identify the efficiency of the treatment by the plant itself. The higher the RTEI indicates the more efficient the treatment by the plant studied. In this research, Eichhornia crassipes were used to evaluate its RTEI value in removing heavy metals cadmium (Cd), nickel (Ni) and lead (Pb) from wastewater. E. crassipes were grown in Faculty of Science & Natural Resources’s (FSNR) lake water and spiked with 1 mg/L, 3 mg/L and 5 mg/L of Cd, Ni and Pb respectively. The experiment were conducted within 14 days period to evaluate its potential in phytoremediation of heavy metals from the wastewater. The results showed that the removal of Cd, Ni and Pb by E. crassipes were highest at 1 mg/L respectively. It was observed that E. crassipes were effective in removing Pb compared to Cd and Ni. Antagonistic effects between heavy metals were found in affecting the removal efficiency of each other except for metal Pb. E. crassipes were able to achieve highest RTEI = 0.91 with 98.2% removal of Pb followed by RTEI = 0.52 with 50.2% removal of Cd and RTEI = 0.62 with 44.7% removal of Ni. After 14 days treatment, E. crassipes show significant toxic effects on plant roots and leaves as the concentration of heavy metal increased. The accumulation of heavy metals in plant tissues were shown in ranged from 7.48 mg/kg to 2864.12 mg/kg (Cd), 46.18 mg/kg to 3628.21 mg/kg (Ni) and 2.69 mg/kg to 6012.68 mg/kg (Pb). The results also revealed that the accumulation of heavy metals was higher in the roots than stalks and leaves. It was found that bionconcentration factor (BCF) of Pb, Cd and Ni in root at 1 mg/L were exceed 1000. Study on translocation factor (TF) of all metals were recorded low in ranged of 0.01-0.79 respectively. This indicates that the phytoremediation mechanism uptakes of E. crassipes is rhizofiltration. This study give a better understanding on the potential of E. crassipes in removing heavy metals from wastewater especially industrial wastewater.

English

The aim of this research was to evaluate the capacity of symbiotic efficiency of native rhizobia from soils of the state of Rio Grande do Sul (RS), Brazil in Phaseolus lunatus L. plants. Soil and nodule samples from predominant legume plants such as Desmodium species were collected in seven locations of the state of RS. For the isolation of the rhizobia from the soil samples, lima bean &ldquo;olho de cabra preto&rdquo; variety and &ldquo;leucena&rdquo; (Leucena leucocephala) and plants were used as baits. Subsequently, the symbiotic characterization of the isolates was performed by inoculation on lima bean plants in vitro conditions. The selected bacterial isolates were evaluated for biological nitrogen fixation efficiency in a greenhouse experiment, being determined after: shoot dry mass, root dry mass, nodule dry mass, nitrogen (N) accumulated shoot and calculated the N fixation relative efficiency index. Among the 28 rhizobia isolates tested, 11 induced nodule formation in lima bean. The rhizobia Plu03 and Plu14 stimulated a greater increase of plant dry mass, nodule dry mass and nitrogen accumulation in the shoot, reflecting in a higher relative efficiency index. These results suggest that the isolates Plu03 and Plu14 are more efficient in promoting growth of lima bean, which could be recommended for future agronomic efficiency studies. Key words: Rhizobia, lima bean, biological nitrogen fixation.

Synthesis of Poly(vinyl alcohol) and Liquid Paraffin-Based Controlled Release Nitrogen-Phosphorus Formulations for Improving Phosphorus Use Efficiency in Wheat

Polymer coating of water soluble fertilizers to curb excess solubilization of nutrients is well-acknowledged fact. Lack of information on phosphorus (P) release from controlled release nitrogen-phosphorus (NP) formulation and its impact on nutrient use indices has driven us to conduct this experiment. We developed NP formulations by reacting liquid ammonia and orthophosphoric acid in laboratory. Resulting NP formulations were characterized by solubility fractions, microscopy, spectroscopy, and X-ray diffraction. After coating with poly(vinyl alcohol) (PVA) and liquid paraffin (LP) at 2 and 3 w/w% concentration, P release kinetics and temperature sensitivity (Q10) of the formulations were compared with diammonium phosphate (DAP) at 20 and 30 °C temperature in a P-deficient soil for 120 h of incubation. Finally, nutrient use efficiency and relative efficiency indices were determined from a greenhouse experiment in potted soil to assess the effect of polymer-coated formulations and of DAP at two application rates in comparison with a non-P amended control. Laboratory synthesized NP formulations were alkaline in reaction, definite cubical to hexagonal crystalline structure with smooth surface generating peaks related to P and N in fingerprinting region of Fourier transform infrared spectroscopy. Polymer coating of NP formulations delayed the P release compared with DAP, while LP-coated formulations showing slower P release than PVA-based coatings. Despite LP-coated formulations showed greater temperature sensitivity (Q10), the PVA-based formulation significantly increased yield and biomass accumulation of wheat, with concomitant increase in crop P uptake and P use efficiency. Both LP and PVA-coated formulations showed a significant residual P accumulation in post-harvest soils. The findings underline the potential of polymer coating technology for enhancing P use efficiencies, thereby reducing environmental P footprints.

Comparación de genotipos de frijol negro opaco en suelos ácidos del sur de Veracruz

In southern Veracruz, Mexico, soil acidity is one of the main environmental factors that reduce the production yield of common bean. The objectives of this research were to identify outstanding opaque black bean breeding lines according to their level of adaptation to acid soils and high yield eff iciency with and without the addition of dolomite into the soil, as well as to determine which is the yield component that associates the most to a greater production of beans. During the Fall/Winter season of 2016-17 two trials were performed in Juan Rodríguez Clara, Veracruz, in a land with a soil of initial pH = 4.67. One trial was conducted under stress conditions by soil acidity and the other with 2.58 Mg ha-1 of dolomite, applied to the soil 27 d before sowing. Twelve black bean breeding lines were evaluated and compared to Negro Grijalva and Negro Comapa bean varieties. All beans were arranged in a randomized complete block design with three replicates. The variables measured were dry matter production without grain, weight of 100 seeds, number of pods per plant and grain yield. An analysis of variance of the quantif ied variables and the least signif icant difference (LSD, 0.05) tests for separation of means were performed. Negro Citlali/XRAV-187-3-1-8 showed the best adaptation to acid soil conditions in southern Veracruz, which obtained yields of 911.0 and 706.3 kg ha-1 with and without dolomite, respectively. These values were signif icantly higher than the commercial beans. This breeding line also showed the highest productive eff iciency, since it obtained the highest geometric mean (MGi) values (802.1) and a relative eff iciency index (IERi) of 2.00. Under both conditions of edaphic acidity, the number of pods per plant was the only plant trait that was positively related to seed yield (r = 0.91 ** and 0.87 **, with and without dolomite).