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331.
Amouzoune Mariam Amri Ahmed Benkirane Rachid Kehel Zakaria Al-Jaboobi Muamer Moulakat Adil Abderrazek Jilal Rehman Sajid 《Genetic Resources and Crop Evolution》2022,69(2):839-853
Genetic Resources and Crop Evolution - Sustainable barley (Hordeum vulgare L.) production will require access to diverse ex-situ conserved collections to develop varieties with high yields and... 相似文献
332.
Gora Adnan Hussain Sahu Narottam Prasad Sahoo Sujata Rehman Saima Dar Showkat Ahmad Ahmad Irshad Agarwal Deepak 《International Aquatic Research》2018,10(2):115-131
International Aquatic Research - This work aimed to appraise growth performance, immune responsiveness, bacterial disease resistance and mRNA expression of two antimicrobial peptides in Labeo... 相似文献
333.
Martin Urík Marek Bujdoš Katarína Gardošová Pavol Littera Peter Matúš 《Water, air, and soil pollution》2018,229(2):52
Selenite is an environmental toxicant whose mobility is affected in soil by various natural components, including humic acids, clay minerals, amorphous ferric oxyhydroxides [FeOx(OH)y], and microorganisms. However, interactions of selenite with these components are usually evaluated separately. Therefore, we addressed selenite behavior in multicomponent system in this study with emphasis on its immobilization and fungal accumulation. Our results highlighted significant acidification of culture medium by common soil fungus Aspergillus niger’s production of protons in selenite presence which affected selenium immobilization. While bentonite and humic acids did not enhanced immobilization efficiency significantly, composite of FeOx(OH)y/humic acids was extremely successful in selenium immobilization. This was most likely by enhanced redox transformation of selenite into elemental selenium as the contribution of each component was synergistic. Subsequently, selenium bioavailability in culture medium decreased and negatively affected bioaccumulation efficiency by fungus. Our results highlighted the significance of multicomponent systems in more realistic evaluation of selenium mobility and transfer to microorganisms. 相似文献
334.
Iodine is an essential trace element for humans, and while plants play an important role in its supplementation, they can also be subject to iodine toxicity. Herein, comparison of iodide and iodate effects on barley (Hordeum vulgare L.) development was evaluated in laboratory experiments when it was cultivated in iodine-spiked agar cultivation media and agricultural soil. Our results show that iodine toxicity is highly dependent on its chemical form and also reflects growth substrate type. Barley responses to iodine presence in agar and soil media suggest that iodide has more severe inhibitory effects than iodate on plant growth. Furthermore, the detrimental effect of iodine notably increased in soil with biomass synthesis as the most sensitive physiological parameter to adverse iodide and iodate effects. However, mild iodate and iodide stimulation of barley growth was observed which implies they are beneficial for growth at low concentrations. These effects were more intense when iodine was applied as iodide, especially in soil cultivation system where natural geochemical processes lead to alteration in iodine speciation which significantly increases plant sensitivity to iodine toxicity. 相似文献
335.
Abdul Qayyum Abdul Razzaq Yamin Bibi Sami Ullah Khan Kashif Sarfraz Abbasi 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2018,68(4):283-290
Water stress is one of the major environmental stresses that affect agricultural production worldwide, especially in arid and semi-arid regions. This research investigated the effect of water deficit, induced by PEG-6000 on wheat genotypes (GA-2002, Chakwal-97, Uqab-2000, Chakwal-50 and Wafaq-2001) grown in modified MS medium solution. Osmotic stress caused a more pronounced inhibition in leaf relative water content and leaf membrane stability more sensitive (index in Wafaq-2001 and Uqab-2000) genotypes compared with the tolerant (Chakwal-50, GA-2002 and Chakwal-97) genotypes. Upon dehydration, an incline in proline, total soluble sugar, total soluble protein, superoxide dismutase, peroxidase, catalase and malondialdehyde activity content were evident in all genotypes, especially at osmotic stress of ?8 bars. The observed data showed that status of biochemical attributes and antioxidant enzymes could provide a meaningful tool for depicting drought tolerance of wheat genotypes. The present study shows that genotypic differences in drought tolerance could be likely attributed to the ability of wheat plants to induce antioxidant defense under drought conditions. In order to develop genotypes with stable, higher yields in dry farming conditions, it is necessary to characterise genetic resources based on drought adaptation, determine suitable genotypes, and then use them in breeding programmes. 相似文献
336.
E. Lugo-Cruz F. Zavala-García H. Rodríguez-Fuentes V. Urías-Orona J. A. Vidales-Contreras R. Carranza-De La Rosa G. Niño-Medina 《Gesunde Pflanzen》2018,70(4):179-184
The effect of drought stress on total phenols, hydroxycinnamic acids, and antioxidant capacity in Cebú, DK2027, and DK2034 maize hybrids was evaluated. Compared to irrigation treatment, total phenols decreased in drought stress treatment by 35.34%, 5.59%, and 31.57% in Cebú, DK2027, and DK2034, respectively. In addition, the levels of t-ferulic, c-ferulic and p-coumaric acids decreased by 17.74%, 23.93%, and 29.83% in Cebú, by 8.92%, 8.62%, and 24.03% in DK2027, and by 13.66%, 11.03%, and 10.38% in DK2034, respectively. The predominant hydroxycinnamic acid from bran extracts was t-ferulic (67% to 72%), followed by c-ferulic (20% to 21%), and p-coumaric (7% to 11%) for both irrigation and drought stress treatments, while caffeic and sinapic acids were found in traces or were not detected. The antioxidant capacity decreased by 8%, 3%, and 9% in trolox equivalents and 7%, 17%, and 14% in percentage of radical scavenging activity for Cebú, DK2027, and DK2034 genotypes, respectively. The reduction of total phenols, hydroxycinnamic acids, and antioxidant capacity is due to the radical scavenging and photoprotective actions of hydroxycinnamic acids against highly reactive oxygen species generated under drought stress treatment. 相似文献
337.
Transfer of Heavy Metals from Soils to Vegetables and Associated Human Health Risks at Selected Sites in Pakistan 总被引:1,自引:0,他引:1
Zahir Ur REHMAN Sardar KHAN Mohammad Tahir SHAH Mark L. BRUSSEAU Said Akbar KHAN Jon MAINHAGU 《土壤圈》2018,28(4):666-679
Contamination of the food chain with heavy metals is considered as one of the major environmental pathways of human exposure to metals leading to potential health risks. This study aimed to investigate the concentrations of heavy metals such as copper (Cu), zinc (Zn), chromium (Cr), nickel (Ni), and manganese (Mn) in agricultural soils and food crops (fruit, leaf, and root vegetables), and their associated health risks to the local population in selected southern districts of Khyber Pakhtunkhwa Province, Pakistan. The concentrations of the selected metals in soil varied over a wide range, in the following decreasing order: Mn > Zn > Cr > Ni > Cu. The bioaccumulation of metals in vegetables was within the permissible risk limits, except for Cr which showed higher contamination in all the tested food crops. The trend of metal transfer factors for different vegetables was in the order of Cu > Ni > Cr > Mn > Zn, while the calculated daily intake of metals (DIM) in adults and children through consumption of food crops was in the decreasing order of Mn > Zn > Ni > Cr > Cu. The health risk index (HRI) values for the heavy metals for both adults and children were less than 1. Therefore, no significant health risk is anticipated for the local consumers through ingestion of these food crops. 相似文献
338.
Imad Khan Hafsa Zaneb Saima Masood Saima Ashraf Hafiz F. Rehman Sajid K. Tahir Habib U. Rehman Adnan Khan Raheela Taj Sadeeq U. Rahman Muqader Shah 《The Journal of Poultry Science》2022,59(3):272
The current study aimed to evaluate the efficacy of selenium nanoparticles (SeNPs), combined or loaded with chitosan (COS), in broiler chickens reared under standard management protocols. The parameters under investigation were production performance, organ development, components of the intestinal barrier, and ileal microbial count. Two hundred and forty day-old chicks were raised in five groups, with each group containing eight replicates (n=6/replicate). The control group received a basal diet whereas the other four groups received basal diets supplemented with SeNPs (0.5 mg/kg), COS (200 mg/kg), SeNPs+COS (0.5 mg/kg SeNPs + 200 mg/kg COS), and SeNPs-loaded COS (SeNPs-L-COS) (200 mg/kg) respectively. On day 35, two birds/replicate were sampled to collect the viscera under investigation. The results revealed that dietary inclusion of SeNPs-L-COS increased (p<0.05) the body weight gain and improved (p<0.05) feed conversion ratio. Similarly, SeNPs-L-COS supplementation increased (p<0.05) the small intestinal villus surface area as well as the count of acidic goblet cells and intraepithelial lymphocytes when compared with the control group. Whereas the total goblet cell count was higher (p<0.05) in the small intestines of both the SeNPs+COS and SeNPs-L-COS groups. Microbial analysis of ileal contents also revealed an increase (p<0.05) in Lactobacilli species count with a concurrent decrease (p<0.05) in Escherichia coli count in the SeNPs-L-COS group when compared with the COS and control groups. Based on the results of the current trial, we can conclude that supplementation with SeNPs-L-COS is a superior combination for promoting the gut health and performance of broilers. 相似文献
339.
A. Ghafoor G. Murtaza M. Z. Rehman Saifullah M. Sabir 《Land Degradation \u0026amp; Development》2012,23(1):1-9
Due to increased population and urbanization, freshwater demand for domestic purposes has increased resulting in a smaller proportion for irrigation of crops. We carried out a 3‐year field experiment in the Indus Plains of Pakistan on salt‐affected soil (ECe 15·67–23·96 dS m−1, pHs 8·35–8·93, SAR 70–120, infiltration rate 0·72–0·78 cm h−1, ρ b 1·70–1·80 Mg m−3) having tile drainage in place. The 3‐year cropping sequence consisted of rice (Oryza sativa L.) and wheat (Triticum aestivum L.) crops in rotation. These crops were irrigated with groundwater having electrical conductivity (EC) 2·7 dS m−1, sodium adsorption ratio (SAR) 8·0 (mmol L−1)1/2 and residual sodium carbonate (RSC) 1·3 mmolc L−1. Treatments were: (1) irrigation with brackish water without amendment (control); (2) Sesbania (Sesbania aculeata) green manure each year before rice (SM); (3) applied gypsum at 100 per cent soil gypsum requirement (SGR) and (4) applied gypsum as in treatment 3 plus sesbania green manure each year (GSM). A decrease in soil salinity and sodicity and favourable infiltration rate and bulk density over pre‐experiment levels are recorded. GSM resulted in the largest decrease in soil salinity and sodicity. There was a positive relationship between crop yield and economic benefits and improvement in soil physical and chemical properties. On the basis of six crops, the greatest net benefit was obtained from GSM. Based on this long‐term study, combined use of gypsum at 100 per cent soil gypsum requirement along with sesbania each year is recommended for soil amelioration and crop production. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
340.
Muhammad Ayaz Urte Stulpinaite Dalia Feiziene Vita Tilvikiene Kashif Akthar Edita Baltrėnaitė-Gedienė Nerijus Striugas Urooj Rehmani Sahib Alam Rashid Iqbal Monika Toleikiene Modupe Doyeni 《Soil Use and Management》2022,38(2):1307-1321
Management of heavy metal-contaminated soil under drought and other harsh hydrological conditions is critical for protecting soil ecosystem services. In this study, we examined the effect of pig manure digestate-derived biochar as a soil amendment (15 t ha−1) with N fertilizer (180 kg ha−1) on soil and plant heavy metal levels and nutrient availability under various moisture regimes (optimal moisture ~15%, drought condition ≤5%, and flooded condition ≥35% wt.). It was observed that biochar applications significantly decreased heavy metals in the spring wheat plants, lowering Cr by 90%, Ni by 50%, Cd by 9% and Pb by 34% compared to non-biochar (control) treatments. However, the pig digestate-derived biochar increased heavy metals in soil under all moisture regimes, increasing soil Cr by 21%, Ni by 43%, Cu by 55%, Zn by 70%, and Pb by 12%. The availability of macroelements also increased with the biochar applications under the optimum moisture regimes in both soil and plants, increasing Mg2+ by 11%, P by 4%, K+ by 50%, and Ca2+ by 56% in the soil, and Mg2+ by 13%, P by 69%, K+ by 29, and Ca2+ by 39% in plants. Biochar addition also improved chlorophyll fluorescence (CF) levels in the crop for the entire season (12th to 62nd day) and the aboveground crop biomass and dry matter contents both increased. Consequently, the use of pig manure digestate-derived biochar with N fertilizer under normal moisture conditions was able to reduce heavy metal availability to plants and thus could be used in contaminated soils to maintain better crop growth and development. 相似文献