Evaluation of photosynthesis,physiological, and biochemical responses of chickpea (Cicer arietinum L. cv. Pirouz) under water deficit stress and use of vermicompost fertilizer

One goal in the face of drought stress conditions is to increase growth and yield through the reduction of negative effects of stress. Vermicompost can play an effective role in plant growth and development and in reducing harmful effects of various environmental stresses on plants due to its porous structure, high water storage capacity, having hormone-like substances, plant growth regulators, and high levels of macro and micro nutrients. This study considered the physiological, biochemical, and photosynthetic responses of the chickpea to different combinations of vermicompost and water stress in a greenhouse environment. Two factors were involved, addition of vermicompost to soil at four ratios: control (100 wt% (weight percentage) soil); 10 wt% vermicompost+90% soil; 20 wt% vermicompost+80 wt% soil; 30 wt% vermicompost+70 wt% soil weight percentage, and treatment of water stress at three levels including 75, 50, and 25% of field capacity. The results showed that vermicompost had a significant effect on all traits under stress and non-stress conditions. Application of vermicompost in soil, especially at the levels of 20 and 30 wt% significantly increased all studied traits under non-stress conditions. Under moderate stress conditions, vermicompost at 30 wt% treatment resulted in a significant increase in the photosynthetic pigments, CO₂ assimilation rate, internal leaf CO₂ concentration, transpiration, the maximal quantum yield of photosystem II (PSII) photochemistry (F_v/F_m), concentrations of Ca and K in root and leaf tissues, proline and soluble protein contents in root tissues. Peroxidase (POX) and catalase (CAT) enzyme activities decreased significantly with increasing proportions of vermicompost, but the activity of superoxide dismutase was not significantly different. In conclusion, the above results showed that vermicompost fertilizer had a positive effect on physiological, biochemical, and photosynthetic responses of chickpea under non-stress and moderate stress conditions, but no positive effect was determined under severe water stress.     

Evaluation of vermicompost fertilizer application on growth,nutrient uptake and photosynthetic pigments of lentil (Lens culinaris Medik.) under moisture deficiency conditions

Vermicompost can play an effective role in plant growth and also in reducing harmful effects of various environmental stresses on plants due to its porous structure, high-water storage, having hormone-like substances and also high levels of macro and micro nutrients. Application of vermicompost in soil, especially at the levels of 15 and 25 Wt% significantly increased all studied traits under non-stress conditions. Under temperate and severe stress conditions, vermicompost at 25 Wt% treatment resulted in a significant increase in plant height (+10% +21%), number of pod (+44% +65%), root dry weight (+63% +66%), shoot dry weight (+50% +89%), leaf area (+6% +7%), root area (+65% +35%). The leaf calcium (Ca) (+62% +67%), leaf potassium (K) (+39% +45%) and root Ca (+33% +34%) under temperate and severe stress, increased using of 25% vermicompost. In conclusion, we suggested that application of vermicompost had a positive effect on lentil under moisture deficit stress.     

Molecular identification of <Emphasis Type="Italic">Chilli leaf curl India virus</Emphasis> along with betasatellite molecule causing leaf curl disease of menthol mint (<Emphasis Type="Italic">Mentha arvensis</Emphasis> var. Kosi) in India

Whitefly-transmitted begomovirus induces leaf curling and stunting of Mentha arvensis (Kosi) and is responsible for heavy economic losses in and around Lucknow, India. The complete genome was amplified, sequenced and assembled as 2759 bp long, with 1376 bp betasatellite molecule. Because no DNA-B amplicon was detected, the virus was classified as “Old World begomovirus” with the characteristic seven ORFs; two ORFs (AV1, AV2) in the V-sense and five ORFs (AC1–AC5) in the C-sense. BLASTn and phylogenetic analysis showed highest similarity (98%) with chilli leaf curl India virus (ChiLCINV). This is the first report of ChiLCINV infection in M. arvensis (Kosi) from India.     

A comparative study to evaluate efficiency of EDTA and calcium in alleviating arsenic toxicity to germinating and young <Emphasis Type="Italic">Vicia faba</Emphasis> L. seedlings

Purpose

This study delineated the effect of calcium (Ca) and ethylenediaminetetraacetic acid (EDTA) addition on arsenic (As) accumulation and physiological attributes of Vicia faba L.

Materials and methods

Two separate experiments were performed. In the first experiment, V. faba seedlings, grown under hydroponic conditions, were exposed to three levels of As (25, 125 and 250 μM) in the presence and absence of three levels of EDTA (25, 125, 250 μM) and calcium (CaCl₂: 1, 5 and 10 mM). The effect of EDTA and Ca on As accumulation and physiological attributes of V. faba was assessed by determining As contents in roots and shoot, chlorophyll contents, H₂O₂ contents, and lipid peroxidation in young and old leaves. In the second experiment, V. faba seeds were grown in As-contaminated sand culture using the same treatment plan.

Results and discussion

The accumulation and toxicity of As to V. faba plants increased with increasing As levels in nutrient solution. Arsenic exposure enhanced the production of reactive oxygen species (ROS) in both roots and leaves, which resulted in lipid peroxidation and decreased chlorophyll contents. The presence of both EDTA and Ca, in general, significantly decreased As accumulation by V. faba seedlings, Ca being more effective than EDTA. Both the amendments decreased As-induced reactive oxygen species (ROS) production and lipid peroxidation. In the case of chlorophyll contents, EDTA significantly decreased chlorophyll contents, while Ca significantly increased chlorophyll contents compared to As. The effect of all the treatments was more pronounced in roots than leaves and in young leaves compared to old leaves.

Conclusions

It is proposed that EDTA and Ca greatly affect As accumulation and toxicity to V. faba, and the effect varies greatly with their applied levels as well as type and age of plant organs. The germinating seedlings of V. faba may be preferred for risk assessment studies, while transplanting 1-week-old V. faba seedlings to As-contaminated soils can decrease its toxicity.

     

A metabolic approach to understanding adaptation to sea water by endangered Persian sturgeon,Acipenser persicus fingerlings

In this study, metabolic responses of Persian sturgeon fingerlings to hyperosmotic condition were investigated by NMR‐based metabolomics. Persian sturgeon fingerlings (n = 2010, mean total weight: 3.2 ± 0.6 g; mean total length: 8.5 ± 1.5 cm) were held in freshwater (FW) for 96 hr and then acclimated in brackish water (BW) (12 g/L) for 24 hr. Blood samples were taken before and after salinity acclimation. The major metabolite changes corresponding to salinity acclimation were related to amino acids, osmolytes and energy metabolites. The plasma glucose levels increased significantly after 24 hr acclimation in BW (p < .05). Other energetic metabolites (acetate, acetoacetate, beta‐hydroxybutyrate, phosphocreatine, creatine, glycerol) showed no significant changes after 24 hr salinity challenge (p > .05). The osmolytes (taurine, trimethylamine‐N‐oxide, choline, N,N‐dimethylglycine) and amino acids (aspartate, glutamate, glutamine, leucine, phenylalanine, β‐alanine, histidine, threonine, cysteine) declined significantly after 24 hr acclimation in BW (p < .05). However, the levels of glycine elevated after 24 hr acclimation in BW (p < .05). Other amino acids including aspargine, isoluecine, Tyrosine, Tryptophan, Valine, and Lysine showed no significant changes after salinity challenge (p > .05). The considerable decreases in almost all plasma amino acids and all osmolytes showed specific importance of these metabolites in osmotic adaptation of fish in BW. Also, it seems that Persian sturgeon fingerlings rely more on oxidation of glucose to meet energetic requirements of osmoregulation than oxidation of lipids, as we observed no detectable changes in metabolites associated with lipid oxidation during osmotic acclimation in BW. Our results may help to understand osmoregulation in a chondrostei fish species from a metabolic approach.     

Integrated nutrient management for better quality and yield of Kinnow mandarin

This study was carried out to determine the integrated effect of organic matter alone and in combination with chemical fertilizers in order to maintain the nutritional status in Kinnow fruit plants. Lahore Compost was used as a source of organic matter. Treatments were made by using compost alone and in combination with nitrogen, phosphorus, potassium (NPK), and well-rotten farm yard manure (FYM; cow dung). Treatments were applied before flowering and after fruit set. Effect of these treatments on different physicochemical characteristics of Kinnow fruit and nutritional status in tree leaves was determined. Among all treatments, minimum flower drop, maximum yield, and better fruit quality were recorded in plants where 40 kg compost + 1/2 recommended doses of NPK were applied before flowering and after fruit setting, while minimum fruit set was recorded from the plants where 30 kg compost alone was applied before flowering.     

Genetic diversity studies of coarse and fine rice using RAPD markers

The availability of a genetically diverse gene pool is vitally important in varietal development. Molecular markers are being extensively utilized to explore the genetic diversity among native and exotic germplasm. This study was designed to reveal the genetic diversity and patterns of relationships among the 20 accessions/genotypes representative of basmati and non-basmati rice from the existing rice gene pool using RAPD markers. Employing RAPD, 17 decamer oligonucleotide primers directed the amplification of 116 fragments, out of which 101 were polymorphic (87.06%) while 15 fragments were monomorphic (12.93%). Similarity coefficients had ranged from 0.47 to 0.90. The average genetic similarity was calculated 0.68 (68%). In this study, the coarse rice genotypes showed more polymorphism (85.84%) than the fine rice genotypes (61.76%). Genotypes were clustered into 8 distinct groups: A, B, C, D, E, F, G, and H but two genotypes, i.e., Shadab and Kangni-27 showed divergence from all the genotypes of the groups. Therefore, these diverse genotypes may be included in future breeding programmes.     

Effect of cross-sectional morphology and composite structure of glass fiber felts on their corresponding acoustic properties

This paper presents the effect of cross-sectional morphologies and composite structures of glass fiber felts on their corresponding acoustic properties. Glass fiber felts with random and layered cross-sectional structure are produced by centrifugal-spinneret-blow system. Acoustic properties are determined by a B&K impedance tube. The results show that sound transmission loss (STL) of glass fiber felts with layered cross-sectional structure exhibit greater than that with random cross-sectional structure. However, there is a little difference between the absorption coefficient values for random and layered cross-section. It means that glass fiber felts with layered cross-section are better to improve the sound insulation. With the increase of thickness, STLs of glass fiber felts with the same areal density do not increase monotonically due to the changing of porosity and characteristic impedances. Different glass fiber felts with layered cross-sectional structure are combined to form a variety of composite structures. It finds that assembly order of glass fiber felts have an effect on the total sound insulation. The large mismatch between the acoustic impedances causes multiple reflections leading to the best STL.     

Response of Yield and Some Physiological Traits of Groundnut (Arachis hypogaea L.) to Topping Height and Application Methods of Zn and Ca Nano-Chelates

Groundnut is an annual legume and important oilseed crop in the world. In order to evaluate the influence of the topping height and application methods of Zinc (Zn) and Calcium (Ca) nano-chelates on quantitative and qualitative characteristics of groundnut, these experiments were carried out during the 2016–2017 cropping seasons on groundnut in Iran. Both foliar and in soil applications of Zn and Ca nano-chelates improved groundnut yield. Foliar application of Zn nano-chelate in combination with topping the main stem 20 cm above the ground produced the highest 100-seed weight (82.19 g), seed yield per unit area (2722.5 kg.h^?1), harvest index (57.53%), biological yield (6540.00 kg.h^?1), oil yield (1486.76 kg.h^?1), protein yield (742.66 kg.h^?1), seed Zn content (12.08 ppm) and Ca content (35.86 ppm). The application of Zn nano-chelate had different positive influences on vegetative and reproductive growth of groundnut plants. Generally, optimizing of the nutritional status in groundnut plants with Ca and Zn supplements is recommended to enhance the quantitative and qualitative yield of groundnut.     

Bioavailability of Arsenic and Antimony in Terrestrial Ecosystems: A Review

Arsenic (As) and antimony (Sb) are metalloids that belong to group 15 of the periodic table and exhibit toxic properties in the environment. They mostly occur naturally at low concentrations in soil, although these can be significantly elevated in both aquatic and terrestrial food chains as a result of dispersion from anthropogenic sources, e.g., mining activities. The bioavailability, i.e., the proportion of the contaminant in soil and dust that is available for uptake by plants and other living organisms, presents the greatest risk to terrestrial ecosystems. Various in vivo and in vitro methods have been used to measure As and Sb bioaccessibility in soil and dust. In vivo measurement of bioavailability can be time consuming, expensive, and unethical; thus, in vitro methods are commonly preferred. However, there is considerable uncertainty around the efficacy of in vitro tools used to measure the bioavailable fractions of As and Sb. The results of these methods are dependent on many variables, e.g., soil characteristics, contaminant sources, and chemical composition of in vitro methods. Therefore, substantial variations are observed between in vitro and in vivo results obtained from different test animals and endpoints. In this paper, we review the literature on As and Sb bioavailability in terrestrial ecosystems and current in vivo and in vitro techniques used for assessing bioavailability and bioaccessibility of metalloids. This would reveal research gaps and allow scientists and environmental policy makers to gain a deeper understanding of the potential risks associated with these metalloids in the environment.