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51.
An experiment was conducted to access the genetic variability among early vigour and quantitative traits under limited moisture in F2 generation of a 5 × 5 diallel cross of bread wheat. The results indicated that there was significant genotypic variation among the genotypes. Additive dominance model revealed full fitness of the data for RL, DSW, FRW, DRW, spike length, and 1000-grain weight but was partially fit for SL, FSW, R/S, tillers per seedling, plant height, tillers per plant, spikelets per spike, and grain yield per plant. The partially adequate models for these plant characters might be due to the presence of non-allelic interaction, linkage, and non-independent distribution of the genes in the parents. Additive genes coupled with moderate to high narrow sense heritability were involved in the heritage of all the traits, which indicated a higher scope of selection in early generations.  相似文献   
52.
Cereal grains such as wheat, rice, and maize are widely consumed as a staple food worldwide. Lead (Pb) is one of the non-essential trace elements and its toxicity in crops especially cereals is a widespread problem. The present review highlighted Pb toxicity in cereal and management strategies to reduce its uptake in plants. Lead toxicity reduced the cereal growth, photosynthesis, nutritional value, yield, and grain quality. The response of cereals to excess varies with plant species, levels of Pb in soil, and growth conditions. Reducing Pb bioavailability in the soil is a viable approach due to its non-degradability either by microbes, chemicals, or other means. Cultivation of low Pb-accumulating cultivars may reduce the risk of Pb toxicity in plants and humans via the food chain. Use of plant growth regulators, microbes, organic, and inorganic amendments might be promising techniques for further decreasing Pb contents in shoot and grains. Soil amendments along with selecting low Pb-accumulating cultivars might be a feasible approach to get cereal grains with low Pb concentrations. Furthermore, most of the studies have been conducted under controlled conditions either in hydroponic or pots and less is known about the effects of Pb management approaches under ambient field conditions.  相似文献   
53.
Alligator weed (Alternanthera philoxeroides) is the most troublesome invasive weed in transplanted rice ecosystems worldwide. A two-year field study was conducted to estimate economic threshold levels and the season long competitive effect of six alligator weed densities (0, 2, 4, 8, 16, and 32 plants m?2) on yield and quality traits of transplanted rice. A gradual linear incline in dry weight of alligator weed was observed with an increase in its density from 2 to 32 plants m?2. Maximum N (15.93–18.26 kg ha?1), P (15.10–16.46 kg ha?1) and K (16.34–17.81 kg ha?1) uptake by alligator weed was recorded at its density of 32 plants m?2. More micronutrient loss to the tune of 6.53, 47.92, 19.99, and 38.42 mg kg?1 for Cu, Fe, Zn, and Mn, respectively was observed at the same density. Increasing density of alligator weed caused more losses in paddy yield (up to 21.37–23.78%), amylose and rice grain protein contents. According to a nonlinear hyperbolic regression model, maximum paddy yield loss of rice at asymptotic value of alligator weed density was 38.8% during 2011 and 42.4% during 2012. Economic threshold value of alligator weed was estimated 1.5 and 1.3 plants per m2 during 2011 and 2012, respectively.  相似文献   
54.
Peach fruit is enriched with natural antioxidants but oxidation caused by biotic and abiotic stresses, reduce these antioxidants and consequently effect the quality and yield of the fruit. Therefore, an experiment was conducted to investigate the role of ascorbic acid to sustain the natural antioxidant activity, improve the fruit quality and yield of peach cultivars (Early Grand and Florida King). The peach cultivars, Early Grand and Florida King were tested against four levels of ascorbic acid (200, 400, 600 and 800?ppm) and compared with control as water spray. The foliar application of ascorbic acid significantly influenced anti-oxidant activity and physico-chemical attributes of peach cultivars. However, the foliar application of ascorbic acid @ 800?ppm significantly increased the fruit weight, fruit yield, fruit firmness, total soluble solids, titratable acidity, antioxidant activity of fruit peel, with least percent infected fruits and fruit juice pH as compared to the rest of the treatments. Similarly, significant variation was recorded for peach cultivars regarding anti-oxidant activity and various physico-chemical attributes. The maximum fruit weight, fruit yield, fruit firmness, total soluble solids, titratable acidity and TSS/TA ratio were noted in fruit of cultivar Florida King. On other side the foliar treated fruit of peach cultivar Early Grand had the highest percent infected fruits, fruit juice pH and antioxidant activity of fruit peel. It is concluded from the significant findings of present research that the peach cultivar Florida King performed better in terms of maximum fruit yield, whereas the cultivar Early Grand produced better quality fruits with high anti-oxidant activity when treated with 800?ppm of ascorbic acid as foliar spray.  相似文献   
55.
In this study, in-house isolated laccase isoforms, i.e., Lac-I and Lac-II of the basidiomycete Pycnoporus sanguineus (CS43), were evaluated in relation to their Remazol Brilliant Blue R (RBBR) dye degradation capacity. A modified Dhouib medium additionally supplemented with 3% ethanol as a secondary inducer was used to propagate P. sanguineus CS43 for enhanced production of laccase under liquid state fermentation. The crude laccase extract was purified by passing through ion exchange diethylaminoethanol (DEAE)-Sepharose and gel filtration-based Sephadex G-200 column chromatography. The purified laccase fractions were subjected to the electrophoresis, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis revealed two laccase isoforms Lac-I and Lac-II with 66 and 68 kDa, respectively. To explore the industrial applicability, for RBBR dye, degradation efficiencies ranged from 82 to 88% after 3 h of incubation for both; Lac-I and Lac-II at both concentrations were recorded. However, with 8 U/mL, the degradation ranged between 70 to 80% during the first 5 min of incubation. Enhanced degradation of RBBR dye was obtained in the presence of violuric acid and N-hydroxypthalamide as laccase mediators. Finally, using RBBR as a substrate kinetic characterization of both Lac-I and Lac-II isoforms was performed that revealed K m (0.243 and 0.117 mM for Lac-I and Lac-II) and V max (1.233 and 1.012 mM/Sec for Lac-I and Lac-II) values, respectively.  相似文献   
56.
The effects of selenium (Se) cadmium (Cd) interactions on plant growth and metabolism are not fully clear. In the present study, we assessed whether Se could alleviate the toxic effects of Cd on growth and metabolism of maize. Seeds of maize variety FH-985 were sown in pots filled with sand treated with CdCl2 (0, 50 and 100 µM) and Se (0, 2 and 4 mg L?1) through Hoagland’s nutrient solution. Low Se (2 mg L?1) increased germination percentage and rate, while high Se (4 mg L?1) increased fresh and dry biomass under Cd stress. Interestingly, all Se concentrations were effective in alleviating the toxic effects of Cd on photosynthetic pigments, whereas higher Se mitigated the Cd-induced oxidative stress and increased flavonoids both in the shoots and roots while phenolics in the roots. The results demonstrated that root zone Se altered tissue-specific primary metabolism in maize. Furthermore, low Se mitigated the Cd-induced decrease in total proteins in the root. Overall, Se-mediated decrease in the oxidative stress in the shoots while increase of secondary metabolites in the roots helped the plants to grow faster at early growth stage and caused increase in the biomass under different Cd regimes.  相似文献   
57.
Animal rearing is the major occupation of most population of South Asian countries. Due to lack of resources and limited approach to modern medicine, most of the livestock raisers prefer to use plant-based traditional medicine also referred to as ethnoveterinary medicine (EVM). Indeed, the use of medicinal plants in South Asia dates back to several centuries with documented evidences. However, there is currently a dearth of documentation and compilation of use of medicinal plants for animal diseases in this part of the world. This review aims to provide an up-to-date compilation of common medicinal plants used for the treatment and/or management of common animal diseases in South Asian countries. Extensive literature search was conducted online and relevant data was retrieved from well-known scientific databases. A total of 276 plants belonging to 95 families have been documented to be in common use for managing 14 different categories of animal diseases. Solanaceae, Lamiaceae, Fabaceae, and Leguminosae were most common plant families in terms of their plant species used for EVM. Gastric diseases were commonly reported and accounted for 72 species of plants used for its treatment followed by the miscellaneous disorders category and skin diseases comprising of 65 and 39 plant species respectively. Herbs accounted for 46% of the total plant species, followed by trees (33%), and shrubs (18%). The EVM were applied through different routes of administration; oral administration accounted for 72% followed by topical application 27%, while burning of plant parts to create smoke around animals to repel insects was less common (1%). It is anticipated that the present review will stimulate further ethnoveterinary research among livestock disease management practices in South Asia.  相似文献   
58.
Field populations of beet armyworm, Spodoptera exigua (Lepidoptera: Noctuidae), from Pakistan were assessed for their resistance to the chlorinated hydrocarbon endosulfan, the organophosphates chlorpyrifos and quinalphos, and the pyrethroids cypermethrin, deltamethrin, bifenthrin and fenpropathrin. Using a leaf-dip bioassay, resistance to endosulfan was high during 1998–2000 but declined to very low, to low levels during 2001–2007, following a reduced use of the insecticide. Organophosphates and pyrethroids were consistently used over the past three decades, and the resistance had been increasing to these insecticide classes. Generally, the resistance to chlorpyrifos and pyrethroids remained low from 1998 to 2002–2003, but resistance increased to moderate to high levels from 2003–2004 to 2006–2007. For deltamethrin, resistance was very high during 2004–2007. Quinalphos resistance remained low during 1998–2006. Correlation analysis of LC50 and LC90 values showed a positive correlation between organophosphates and pyrethroids, but no correlation between endosulfan and organophosphates or pyrethroids tested herein. These results suggest that the conventional chemistries should be replaced with new chemistries for the successful management of S. exigua.  相似文献   
59.
Thirty-six Thalli male growing lambs were used in a completely randomized design with 2 × 2 factorial arrangement of treatments to evaluate the effect of varying levels of energy and protein on nutrient intake, digestibility, weight gain, and gain to feed ratio. Four experimental diets, i.e., low energy–low protein (LE-LP), low energy–high protein (LE-HP), high energy–low protein (HE-LP), and high energy–high protein (HE-HP) were formulated. The low- and high-energy diets contained 2.3 and 2.7 MJ/kg dry matter (DM) with 12% and 14% of crude protein. The lambs were fed ad libitum. Dietary energy and protein levels and their interactions influenced the nutrient intake. Maximum dry matter intake was noted in animals fed LE-HP diet followed by LE-LP, HE-HP, and HE-LP diets. Digestibility of DM and N increased (P < 0.01) and that of neutral detergent fiber decreased (P < 0.01) linearly with increasing levels of dietary energy and protein. Digestibility of N was only affected by protein level and interaction between energy and protein levels. Average daily gain was higher (P < 0.01) in lambs fed HE-HP diet followed by LE-HP, LE-LP, and HE-LP diets. Dietary energy and protein levels and their interaction had significant effect (P < 0.01) on gain to feed ratio.  相似文献   
60.
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