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1.
A pot experiment was conducted in a climate‐controlled greenhouse to investigate the growth, physiology and yield of potato in response to salinity stress under biochar amendment. It was hypothesized that addition of biochar may improve plant growth and yield by mitigating the negative effect of salinity through its high sorption ability. From tuber bulking to harvesting, the plants were exposed to three saline irrigations, that is 0, 25 and 50 mm NaCl solutions, respectively, and two levels of biochar (0 % and 5 % W/W) treatments. An adsorption study was also conducted to study the Na+ adsorption capability of biochar. Results indicated that biochar was capable to ameliorate salinity stress by adsorbing Na+. Increasing salinity level resulted in significant reductions of shoot biomass, root length and volume, tuber yield, photosynthetic rate (An), stomatal conductance (gs), midday leaf water potential, but increased abscisic acid (ABA) concentration in both leaf and xylem sap. At each salinity level, incorporation of biochar increased shoot biomass, root length and volume, tuber yield, An, gs, midday leaf water potential, and decreased ABA concentration in the leaf and xylem sap as compared with the respective non‐biochar control. Decreased Na+, Na+/K+ ratio and increased K+ content in xylem with biochar amendment also indicated its ameliorative effects on potato plants in response to salinity stress. The results suggested that incorporation of biochar might be a promising approach for enhancing crop productivity in salt‐affected soils. 相似文献
2.
Plants display an array of classical strategies to maximize phosphate (Pi) acquisition from sparingly soluble P sources. Acclimation to Pi-stress via elegant Pi-starvation induced (PSI) adjustments would reduce our current overreliance on expensive, polluting and non-renewable Pi-fertilizers. Nevertheless, differences in the ability of various species to solubilize sparingly soluble P-sources have been often evidenced; inter-cultivar variations are scarcely documented. Brassica is known as an effective, non-mycorrhizal user of sparingly soluble P-sources. Various growth parameters and biomass accumulation by genetically diverse Brassica cultivars were determined in four experiments using hydroponics and quartz sand culture media. Role of PSI root mediated pH changes, organic anions (OAs) exudation and altered root architecture in mobilization and acquisition of sparingly soluble P-forms [Jordan rock-P (RP) at 2 g l−1 and Ca3(PO4)2 (TCP) at 0.2 g l−1 respectively] was investigated. Cultivars showed considerable genetic variations in biomass accumulation, various growth parameters and root–shoot ratio. Concentration and total uptake of P, specific absorption rate of P, P-transport rate and P-utilization efficiency (PUE) were also significantly (P < 0.001) different for various cultivars and their dry matter was significantly correlated with P-uptake [r = 0.94** (significant at 1% level)]. P-tolerant cultivars showed substantial decrease in solution media pH because of H+ efflux and exuded more carboxylates than low P-sensitive cultivars under P-starvation. P-uptake by cultivars increased linearly with decreasing pH. The amount and types of OAs exuded from the roots of P-starved plants differed from those of plants grown under P-sufficient environment. In split pot study, with TCP and RP supplied spatially separated from other nutrients, efficient cultivars were still able to mobilize RP and TCP more efficiently than inefficient cultivars. In rhizobox study, the elongation rates of primary roots decreased but the elongation rates of the branched zones of primary roots and the length of lateral roots increased under P-starvation. Tested cultivars showed genetic diversity in accessing, mobilization, acquisition and utilization of Pi from sparingly soluble P forms. An arrange marriage of plant traits can explain cultivar’s access to different forms of sparingly soluble P, and in addition to altered lateral root topology and enhanced P-uptake and PUE, enhanced H+ efflux and OAs exudation are key factors in Pi scavenging from extra cellular sparingly soluble P-forms. 相似文献
3.
Akhtar M Bhanger MI Iqbal S Hasany SM 《Journal of agricultural and food chemistry》2005,53(22):8655-8662
The sorption efficiency of indigenous rice (Oryza sativa) bran for the removal of organics, that is, benzene, toluene, ethylbenzene, and cumene (BTEC), from aqueous solutions has been studied. The sorption of BTEC by rice bran is observed over a wide pH range of 1-10, indicating its high applicability to remove these organics from various industrial effluents. Rice bran effectively adsorbs BTEC of 10 microg mL(-1) sorbate concentration from water at temperatures of 283-323 +/- 2 K. The effect of pH, agitation time between solid and liquid phases, sorbent dose, its particle size, and temperature on the sorption of BTEC onto rice bran has been studied. The pore area and average pore diameter of rice bran by BET method are found to be 19 +/- 0.7 m(2) g(-1) and 52.8 +/- 1.3 nm. The rice bran exhibits appreciable sorption of the order of 85 +/- 3.5, 91 +/- 1.8, 94 +/- 1.4, and 96 +/- 1.2% for 10 microg mL(-1) concentration of benzene, toluene, ethylbenzene, and cumene, respectively, in 60 min of agitation time using 0.1 g of rice bran at pH 6 and 303 K. The sorption data follow Freundlich, Langmuir, and Dubinin-Radushkevich (D-R) models. Sorption capacities have been computed for BTEC by Freundlich (32 +/- 3, 61 +/- 14, 123 +/- 28, and 142 +/- 37 m mol g(-1)), Langmuir (6.6 +/- 0.1, 7.5 +/- 0.13, 9.5 +/- 0.22, and 9.4 +/- 0.18 m mol g(-1)), and D-R isotherms (11 +/- 0.5, 16 +/- 1.3, 30 +/- 2.2, and 33 +/- 2.5 m mol g(-1)), respectively. The Lagergren equation is employed for the kinetics of the sorption of BTEC onto rice bran and first-order rate constants (0.03 +/- 0.002, 0.04 +/- 0.003, 0.04 +/- 0.003, and 0.05 +/- 0.004 min(-1)) have been computed for BTEC at their concentration of 100 mug mL(-1) at 303 K. Studies on the variation of sorption with temperatures (283-323 K) at 100 mug mL(-1) sorbate concentration gave thermodynamic constants DeltaH (kJ mol(-1)), DeltaG (kJ mol(-1)), and DeltaS (J mol(-1) K(-1)). The results indicate that the sorption of organics onto rice bran is exothermic and spontaneous in nature under the optimized experimental conditions selected. This sorbent has been used successfully to accumulate and then to determine benzene, toluene, and ethylbenzene in wastewater sample. 相似文献
4.
Shahbaz Khan Hafeez ur Rehman Muhammad Ashfaq Wahid Muhammad Farrukh Saleem Mumtaz Akhtar Cheema Shahzad Maqsood Ahmed Basra 《Journal of plant nutrition》2016,39(12):1681-1687
The impact of soil (1, 2 kg ha?1) and foliar (100, 200 mg L?1) boron (B) with control (no B) was evaluated on phenology and yield formation of Camelina each applied at stem elongation and flowering stages. Foliar (200 mg L?1) or soil B (2 kg ha?1) resulted in earlier flowering and maturity, increased fruit bearing branches (19.68%), number of siliqua, seeds per siliqua (4.6%), biological yield (15%), seed yield (24%), harvest index (11.4%) and oil contents (23%) than no B. Increased fruit bearing branches, seed filled siliqua or seed numbers, harvest index and oil quality can be attributed to changes in dry matter accumulated of stem with simultaneous increase in siliqua dry weight with foliar or soil applied B. In crux, foliar (200 mg L?1) or soil applied (2 kg ha?1) B seems promising to improve seed and oil yield, harvest index of Camelina sativa under B deficient condition. 相似文献
5.
The biological response modifier human beta-interferon had pronounced antigrowth effects on various histologic types of human brain tumor cells but no effects on a nontransformed cell line, MRC-5. The cultures of brain tumor cells showed severe alterations indicative of cell injury and death after exposure to beta-interferon for 2 to 6 days. Similar results were obtained with cells freshly explanted from human brain tumors. The results indicate that it may be possible to use fresh, explanted tumor tissue to identify patients who might benefit from therapy with beta-interferon. 相似文献
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7.
Muhammad Amjad Javaid Akhtar Muhammad Anwar-ul-Haq Muhmmad Atif Riaz Zulfiqar Ahmad Saqib Behzad Murtaza 《Journal of plant nutrition》2016,39(13):1926-1935
To check the efficacy of potassium in alleviating oxidative stress under salt stress, salt-tolerant (Indent-1) and salt-sensitive (Red Ball) tomato (Lycopersicon esculentum Mill.) genotypes were exposed to three levels of sodium chloride (NaCl) (0, 75, 150 mM) and two levels of potassium (4.5 and 9 mM) in solution and foliar form. Thirty days of treatments revealed that increasing NaCl stress increased lipid peroxidation (malondialdehyde, MDA) and correspondingly the activity of antioxidant enzymes (superoxide dismutase, SOD; catalase, CAT; and glutathione reductase GR) in both genotypes. However, higher potassium (K) level in solution or foliar spray during the salt-induced stress decreased MDA and antioxidant activity and increased the growth in salt-tolerant genotype than in the salt-sensitive genotype. Decrease in MDA concentration, activity of antioxidant enzymes, and increase in the growth of tomato plants by the application of potassium under salt stress suggest that potassium is an effective ameliorating agent against salt-induced oxidative damage. 相似文献
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9.
Summary A pilot health monitoring system was started in 1990 to develop statistically valid data for use in estimating the disease frequencies in dairy cattle and buffaloes. This paper presents the design of the monitoring programme and frequencies of selected diseases. Eighty herds were selected with typical livestock management practices of the farmers in the area. Veterinary assistants visited the farms once a month for 12 months to collect livestock inventory, production, disease and preventive treatment data. The incidence density method was used as a measure of disease frequency.In adults, breeding problems, mastitis and gastro-intestinal problems were the highest reported conditions. Respiratory problems were the commonest in young stock. The calves of both species frequently had gastro-intestinal and respiratory disease conditions. Most of the calf crop of both species were lost within the first 3 months of life.
Monitoreo De Problemas De Salud Bovina En Hatos Lecheros Pequenos En El Territorio Capital De Islamabad
Resumen Se inició un sistema de monitoreo piloto en 1990, con el propósito de desarrollar datos estadísticos válidos para estimar la frecuencia de enfermedades en ganado lechero y en búfalos. Este artículo presenta el diseño del programa de monitoreo y la frecuencia de las enfermedades seleccionadas. Se seleccionaron ochenta hatos con el manejo típico de los ganaderos del área. Los veterinarios visitaron las fincas una vez al mes durante 12 meses para colectar información. El método de densidad en la incidencia fue usado para medir la frecuencia de enfermedades.En adultos, las condiciones más frecuentemente encontradas fueron problemas de fertilidad, mastitis y problemas gastrointestinales. Las afecciones respiratorias fueron el común denominador en jóvenes. Los terneros de ambas especies se encontraron frecuentemente con problemas gastrointestinales y respiratorios, conjuntamente, siendo la mortalidad extremadamente alta en los 3 primeros meses de vida para ambas especies.
Gestion Des Problemes De Sante Bovine De Petits Troupeaux Laitiers Sur Le Territoire De Islamabad: Schema, Donnees Et Frequences De La Maladie
Résumé Un système pilote de gestion de la santé a débuté en 1990 pour développer des données statistiquement valables pour être utilisées dans l'estimation de la fréquence des maladies de bovins laitiers et de buffles. Cet article présente le schéma du programme de gestion et les fréquences des maladies sélectionnées. Quatre vingt troupeaux ont été choisis; leur élevage était conduit selon la méthode propre aux fermiers de la région. Des assistants vétérinaires ont visité les fermes une fois par mois durant 12 mois pour relever les données sur l'inventaire du bétail, la production, les maladies et les traitements préventifs. L'importance de l'incidence a été utilisée comme méthode pour mesurer la fréquence des maladies. Chez les adultes, les problèmes prédominants dans les conditions indiquées concernaient la reproduction, les mammites et des troubles gastrointestinaux. Les problèmes respiratoires étaient les plus communs chez le jeune bétail. Les veaux des deux espèces présentaient fréquemment des troubles respiratoires et gastrointestinaux. La majorité de la production de veaux des deux espèces étaient perdue dans les trois premiers mois de vie.相似文献
10.