Inheritance pattern of mungbean yellow mosaic disease resistance and gene action for different traits in mungbean (Vigna radiata (L.) Wilczek) under protected and unprotected field conditions

Understanding of mungbean yellow mosaic disease resistance is crucial to develop resistant varieties to combat worldwide threat of the disease epidemics. This study was aimed to determine nature of disease resistance in terms of number of genes governing it and genetics of related traits. Experimental site was located on 31.43°N and 73.06°E with an elevation of 186 m, and evaluation trials were conducted during spring season due to high disease epidemics in this season. Two contrasting genotypes, that is, NM 6‐68‐2 (resistant) and NM 1‐32‐1 (highly susceptible), were crossed to raise six populations, that is, P₁, P₂, F₁, F₂, BC₁ and BC₂ for evaluation under protected and unprotected field conditions using chi‐square test and generation mean and variance analysis. It was discovered that disease resistance was governed by two major genes with additive effects. Disease resistance can easily be incorporated through backcrossing and direct selection following hybridization. Direct selection should be practised at earlier generation for plant height, chlorophyll contents and number of seeds per pod due to preponderance of additive effects whereas at later generations for seed yield per plant, 100 seed weight, harvest index, number of pods per plant and pod length due to involvement of duplicate epistasis.     

Estimation of aboveground tree carbon stock using SPOT-HRG data (a case study: Darabkola forests)

Forests are among the most important carbon sinks on earth. However, their complex structure and vast areas preclude accurate estimation of forest carbon stocks. Data sets from forest monitoring using advanced satellite imagery are now used in international policy agreements. Data sets enable tracking of emissions of CO₂ into the atmosphere caused by deforestation and other types of land-use changes. The aim of this study is to determine the capability of SPOT-HRG Satellite data to estimate aboveground carbon stock in a district of Darabkola research and training forest, Iran. Preprocessing to eliminate or reduce geometric error and atmospheric error were performed on the images. Using cluster sampling, 165 sample plots were taken. Of 165 plots, 81 were in natural habitats, and 84 were in forest plantations. Following the collection of ground data, biomass and carbon stocks were quantified for the sample plots on a per hectare basis. Nonparametric regression models such as support vector regression were used for modeling purposes with different kernels including linear, sigmoid, polynomial, and radial basis function. The results showed that a third-degree polynomial was the best model for the entire studied areas having an root mean square error, bias and accuracy, respectively, of 38.41, 5.31, and 62.2; 42.77, 16.58, and 57.3% for the best polynomial for natural forest; and 44.71, 2.31, and 64.3% for afforestation. Overall, these results indicate that SPOT-HRG satellite data and support vector machines are useful for estimating aboveground carbon stock.     

Impact of Various Ratios of Nitrogen and Sulfur on Maize and Soil pH in Semiarid Region

Nitrogen and sulfur play an important role in maize production. The aim of this study was to evaluate the effect of nitrogen (N) and sulfur (S) levels applied in various ratios on maize hybrid Babar yield at Peshawar in 2011 and 2013. Four N levels (120, 160, 200 and 240 kg N ha^?1) and four S levels (20, 25, 30 and 35 kg S ha^?1) were applied in three splits: a, at sowing; b, V8 stage; c, VT stage in ratios of 10:50:40, 20:50:30 and 30:50:20. Grains ear^?1, thousand grain weight, grain yield ha^?1 and soil pH were significantly affected by years (Y), N, S and their ratios, while no effect of N, S and their ratios was noted on ears plant^?1. Maximum grains ear^?1 (390), thousand grain weight (230.1 g) and grain yield (4119 kg ha^?1) were recorded in 2013. N increased grains ear^?1 (438), thousand grain weight (252 g) and grain yield (5001 kg ha^?1) up to 200 kg N ha^?1. Each increment of S increased grains ear^?1 and other parameters up to 35 kg S ha^?1, producing maximum grains ear^?1 (430), thousand grain weight (245 g) and grain yield (4752 kg ha^?1), while soil pH decreased from 8.06 to 7.95 with the application of 35 kg S ha^?1. In the case of N and S ratios, more grains ear^?1 (432), heavier thousand grains (246.7 g) and higher grain yield (4806 kg ha^?1) were observed at 30:50:20 where 30% of N and S were applied at sowing, 50% at V8 and 20% at VT stage. It is concluded that 200 kg N ha^?1 and 35 kg S ha^?1 applied in the ratio of 30% at sowing, 50% at V8 and 20% at VT stage is recommended for obtaining a higher yield of maize hybrid Babar.     

Synthesis,Characterization, and Use of Carbon Microspheres for Removal of Different Dyes from Aqueous Environments

Water, Air, & Soil Pollution - Sustainable groundwater quality has become a major concern for the agro-based country like Bangladesh. Integrated approaches of various irrigation water quality...     

Inhibition of nitrification process by seed oil from Acrocomia totai palm tree

Nitrification inhibitory properties of plant substances offer potential benefits for agricultural applications. In this study, hexane-extracted seed oil, and 10, 20, and 30 mg/pot dry powder of seed exocarp and mesocarp from Acrocomia totai were applied in a quick nitrification bioassay for 24 or 50 hr, as well as for 4 weeks laboratory soil incubation, to investigate their effects on nitrification process. Results showed that applied oil concentrations significantly reduced nitrification rates. The extent of inhibition was increased with the oil concentrations from 5 to 25 µl in both experiments. The exocarp and mesocarp powders also inhibited nitrification, but it was not as high as oil-induced inhibition. Analysis of oil fatty acids showed that oil consisted of 71%, 26%, and 3% of saturated, monounsaturated, and polyunsaturated fatty acids, respectively. This suggests that fatty acids or some unknown ingredients in crude oil could be the responsible inhibiting compound.     

Perusing biochemical antioxidant enzymes as selection criteria under drought stress in wheat varieties

In regard to important roles of enzymatic antioxidant in abiotic stresses, and their practical use as stress indices, the current research was implemented to peruse antioxidant enzymatic activities of different wheat varieties and to find the susceptible and the tolerant varieties based on these indices. The experiment was carried out in the greenhouse of Islamic Azad University, Sanandaj, Iran in 2015. A factorial experiment based on completely randomized design (CRD) with three replications were used to evaluate the effects of different water regimes, including 100% and 50% field capacity (FC) on 25 wheat cultivars. Antioxidant enzyme activities, including superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), and ascorbic peroxidase (APX), and grain yield of the wheat varieties were measured. The results showed that under normal irrigation condition, the relationships between grain yield and antioxidant were inversed, but under stressful condition the relationships between wheat grain yield and some important antioxidants such as CAT and SOD were positive. Among antioxidant enzymes, SOD activity showed a higher variation among wheat varieties of this study, indicating that this enzyme is an important trait to be used in the breeding programs. Based on the results of different statistical techniques and comparing relationships among traits for normal irrigation and stress condition, enzymatic antioxidant could be used as practical criteria for screening tolerant genotypes of wheat. On the other side, SOD and CAT resulted in being the most important criteria for achieving higher tolerant genotypes through indirect selection.     

Effects of nano Fe/SiO2 fertilizers on germination and growth of barley and maize

Iron (Fe) nanoparticles (NPs), with 30–40 nm diameter, were stabilized on sand. The resulting synthesized Fe/SiO₂ NPs, with different Fe contents (0–25 mg kg^?1) were employed as fertilizers in probing the mean germination time (MGT), growth and dry matter of barley and maize and their comparison with common Fe/SiO₂ in a completely randomized design (CRD) experiment. The results showed that our fertilizers had significant effects on MGT, with the lowest of 0.58 day for barley and 0.79 day for maize; at 15 and 5 mg kg^?1 nano Fe/SiO₂, respectively. Application of 15 mg kg^?1 of nano Fe/SiO₂ increased the shoot length: 8.25% and 20.8% for barley and maize, respectively. However, the concentration of 25 mg kg^?1 had a negative impact on shoot length in barley. Increasing the concentrations of both nano and common Fe/SiO₂ particles, increased the root lengths in both plants, however this increase was higher with the application of nano Fe/SiO₂. Likewise, seedling length enlarged with the concentration increase of both Fe/SiO₂ particles and was more pronounced with nano Fe/SiO₂. The application of nano Fe/SiO₂ was more effective compared with the common Fe/SiO₂ in encouraging barley and maize growth. The positive impact was higher in maize than barley.     

Screening of tomato genotypes for salinity tolerance based on early growth attributes and leaf inorganic osmolytes

The experiment containing three replicates of completely randomized factorial treatments was conducted in a glasshouse under controlled conditions with three simulated soil salinity levels (control, 10 and 15 dS m^?1). Morpho-physiological traits (i.e. lengths, fresh weights and dry weights of root and shoot, number of leaves, root/shoot ratio, shoot Na⁺ accumulation, K⁺/Na⁺ ratio, Ca²⁺/Na⁺ ratio, membrane stability index, lycopene contents, chlorophyll-a and -b) were recorded to determine mechanism of salt tolerance of tomato at seedling stage. Principal component analysis (PCA) was used to express a three-way interaction of genotype × salinity level × traits that scattered the 25 tomato genotypes based on their morpho-physiological response to different NaCl levels. The negative association of Na⁺ with all other traits except root/shoot ratio and the morpho-physiological response trend of genotypes exposed that probable mechanism of salt tolerance was initially Na⁺ exclusion by abscising older leaves to have younger physiologically energetic, and lastly a higher activity of plants for root development to sustain them in saline soil. PCA three-way biplot efficiently recognized ANAHU, LA-2821, LO-2752, LO-2707, PB-017909, LO-2831-23 and 017860 as salt tolerant genotypes. On the other hand, ZARNITZA, GLACIER, LO-2692, LO-2576, BL-1079, 006233, 006232, 017856, NUTYT-701 and NAGINA were found to be salt susceptible.     

Isolation and characterization of multi-potential Rhizobium strain ND2 and its plant growth-promoting activities under Cr(VI) stress

Soil contaminated by chromium (Cr) is a major concern for sustainable agriculture. Considering this as a basis, the present study was designed to isolate Cr(VI)-reducing and plant growth-promoting bacterial strain from contaminated sampling sources. In this study, Rhizobium strain ND2 was isolated from the root nodules of Phaseolus vulgaris grown in leather industrial effluent contaminated soil. The strain ND2 exhibited strong resistance to different heavy metals and reduced 30 and 50 µg ml^?1 concentrations of Cr(VI) completely after 80 and 120 h of incubation, respectively, as well as chromium adsorption and immobilization were confirmed by scanning electron microscopic equipped with energy X-ray spectroscopy. In addition, the strain produced 21.73 and 36.86 µg ml^?1 of indole-3-acetic acid at 50 and 100 µg ml^?1 of L-tryptophan supplimentations, respectively. Strain ND2 positively affected the exo-polysaccharide, ammonia, protease and catalase production and stimulated root length of various test crops under Cr(VI) stress. Moreover, Rhizobium strain ND2 has the potential to colonize the diverse agricultural crops. Thus, the present findings strongly suggested that the multipotential properties of ND2 could be exploited for bioremediation of contaminated sites with Cr(VI) as well as potential bio fertilizer for enhancing the agricultural productivity.