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101.
Gholam Ali Akbari Mostafa Hojati Seyed Ali Mohammad Modarres-Sanavy Faezeh Ghanati 《Pesticide biochemistry and physiology》2011,100(3):244-250
The ability of hexaconazole (HEX) to ameliorate salinity stress was studied in canola plants (Brassica napus L.). Canola seedlings were subjected to sodium chloride (NaCl) treatment. A treatment with 200 mM NaCl reduced growth parameters, chlorophyll content and protein content as well as increased the proline (Pro) content in canola plants. In addition, NaCl stress increased the endogenous, nonenzymatic antioxidants and the activity of antioxidant enzymes, such as peroxidase (POX; EC 1.11.1.7), superoxide dismutase (SOD; EC 1.15.1.1) and catalase (CAT; EC 1.11.1.6). When these plants were treated with a combination of NaCl and 50 mg L−1 HEX, the inhibitory effects of NaCl stress were decreased by increasing the root growth, shoot growth, dry weight (DW), chlorophyll content, protein content and antioxidant enzyme activity by ameliorating the salinity injury. These results suggested that HEX has an important role in the enhancement of plant antioxidant systems and resistance to salinity in canola plants. 相似文献
102.
Abu Shamim Mohammad Nahiyan Louisa Robinson Boyer Peter Jeffries Yoh-ichi Matsubara 《European journal of plant pathology / European Foundation for Plant Pathology》2011,130(2):197-203
The diversity of Fusarium populations in asparagus (Asparagus officinalis L.) decline fields in Japan was estimated by PCR-SSCP (single-stranded conformational polymorphism) analysis of the ITS2
regions of the nuclear rRNA genes. This method was used to rapidly and objectively identify pathogens associated with roots
of plants showing symptoms of asparagus decline collected from fields in five regions across Japan. Over 651 fusarial isolates
were obtained, and were easily differentiated into three principal species. Fusarium oxysporum f. sp. asparagi was most frequently isolated from the domestic five regions (68%), whereas Fusarium proliferatum (28.6%) was less frequent. Fusarium solani was found much rarely (2.5%). The frequency of isolation of Fusarium proliferatum increased gradually from the north to the south of Japan, though considerable differences were found between fields in each
region, as well as regional differences among the Fusarium populations. Most of the fusarial isolates were highly pathogenic in vitro. These results reveal that Fusarium oxysporum f. sp. asparagi and Fusarium proliferatum are important biotic factors which lead to asparagus decline in Japan. 相似文献
103.
BACKGROUND: Application of insecticides in modern agriculture in order to enhance legume production has led to their accumulation in soils to levels that adversely affect soil microflora such as rhizobia and exert a negative impact on the physiological activities associated with them. This study was therefore designed to identify rhizobial strains expressing higher tolerance to insecticides fipronil and pyriproxyfen and synthesising plant growth regulators even amid insecticide stress. RESULTS: The fipronil‐ and pyriproxyfen‐tolerant Rhizobium sp. strain MRL3 produced plant‐growth‐promoting substances in substantial amounts, both in the presence and in the absence of the insecticides. In general, both insecticides at recommended and higher rates reduced plant dry biomass, symbiotic properties, nutrient uptake and seed yield of lentil plants. Interestingly, when applied with any concentration of the two insecticides, Rhizobium sp. strain MRL3 significantly increased the measured parameters compared with plants grown in soils treated solely with the same concentration of each insecticide but without inoculant. CONCLUSION: This study suggests that Rhizobium strain MRL3 may be exploited as a bioinoculant to augment the efficiency of lentil exposed to insecticide‐stressed soils. Copyright © 2010 Society of Chemical Industry 相似文献
104.
Alireza Koocheki Seyyed Mohammad Seyyedi 《Communications in Soil Science and Plant Analysis》2020,51(9):1161-1183
ABSTRACT Evaluation of the relationships between nutritional patterns and farms’ age with the behavior of saffron (Crocus sativus L.) daughter corms based on farmers’ management (on-farm) can be crucial in improving saffron sustainable yield. Furthermore, in commercial saffron production, especially in small farms, the purchased water and fertilizers are the basis of sustainable saffron profitability, hence, recognizing the relationships between economic water use efficiency (EWUE) and economic fertilizer use efficiency (EFUE) can be important. An on-farm experiment was conducted on a large scale based on farmers’ management in Torbat Heydarieh, Iran. The farms’ age (1–6 years old) and fertilizers management approaches (organic, mineral and integrated) were considered as the first and second factors, respectively. Large-sized daughter corms number and weight and corms N and P content increased with increasing farms’ age from 1 to 4 years old. However, these parameters decreased with increasing farms’ age from 4 to 6 years old. Irrespective of saffron farms’ age, the minimum large-sized daughter corms number and weight were observed when mineral fertilizer management was practiced. By contrast, the maximum values were related to integrated fertilizer management. In each type of fertilizer management, EWUE and EFUE (based on large-sized daughter corms monetary value) increased with increasing farms age from 1 to 4 years. However, increase in farms age from 4 to 6 years caused a significant reduction in mentioned indices. Overall, if high-quality saffron corm production is needed, corms should be harvested in the fourth year to gain the maximum yield and profit. 相似文献
105.
It has been hypothesized that the uptake of organic as opposed to inorganic nitrogen compounds found in wastewater can be properly substituted for plant nutrients. The objective of this study was to compare effects of applying monosodium glutamate wastewater (MGW) and ammonium nitrate (NH4NO3) (AN) on nitrogen metabolism and growth of lettuce. The results showed that while NH4NO3 (AN), NO3-, nitrite content and NR activity increased the protein content of lettuce. Applying MGW with a high concentration of 17 amino acids and macro- and microelements improved the fresh weights of shoot and root as well as the protein content of lettuce. Antioxidant activities were not affected by AN and MGW, and their interaction effects only increased POD after 8 weeks. In conclusion, substituting a portion of the chemical fertilizers with MGW improved lettuce growth, but did not increase NO3- accumulation in leaves. 相似文献
106.
Mohammad Saeed Vaghar Saeed Sayfzadeh Hamid Reza Zakerin Soheil Kobraee Sayed Alireza Valadabadi 《Journal of plant nutrition》2020,43(18):2740-2756
Abstract To investigate the effect of foliar application of nano-chelates of iron, zinc, and manganese subjected to different irrigation conditions on physiological traits, and yield of soybean (cultivar M9), a split plot experiment was conducted in a completely randomized block design with three replications in two crop years (2016–2017). The main plot included four levels of irrigation (I): full irrigation (I 1), irrigation withhold at flowering stage (I 2), irrigation withhold at podding stage (I 3), and irrigation withhold during the grain filling period (I 4). Also, the subplot included eight levels of foliar application with Fe, Zn, Mn, Fe?+?Zn, Fe?+?Mn, Zn?+?Mn, Fe?+?Zn?+?Mn nano-chelates, and distilled water (control). The results of combined analysis of variance suggested that the effect of irrigation and foliar application of nano-chelate was significant on all traits. Water deficit stress significantly reduced the grain yield. The minimum numbers of pods per plant, number of grains per plant, 100-seed weight per plant, leaf area index, leaf chlorophyll concentration, total dry weight of plant, and the grain yield were obtained by irrigation withhold at podding stage. Foliar application of combined nano-chelates increased the soybean resistance against water shortage more considerably than the separate consumption of these elements. Under drought stress in podding stage, the application of Fe?+?Zn led to the highest yield with a mean of 2613.84?kg ha?1 where this increase was 61.1% higher than control. 相似文献
107.
Mesbah Babalar Salim Mohammad Sokri Hosein Lesani Mohammad Ali Asgari 《Journal of plant nutrition》2015,38(14):2247-2258
Evaluations of vegetative growth and leaf concentrations of nitrogen (N), potassium (K), calcium (Ca), magnesium (Mg), and iron (Fe) were made of apple (Malus domestica Borkh. cvs. Granny Smith, Gala, and Golab) grown with five treatments of NO3?:NH4+ ratios in pot culture. The concentrations of NO3?:NH4+ ratios were 2.5:0.1, 6:0.3, 6:0.5, 6:0.7, and 6: 1 meq L?1. Regression analysis showed that growth parameters of main stems and branches were not affected by increases of NH4+ in the ratios. Granny Smith, Gala, and Golab differed in some of these parameters. Concentrations of N and Fe increased as NH4+ increased, whereas K and Ca decreased and Mg was not affected significantly. Generally, the treatment of 2.5:0.1 produced leaves with lower N but higher K, Ca, and Mg concentrations than the other treatments. This research showed that vegetative growth was not affected by NH4+ concentration whereas elemental composition was affected. 相似文献
108.
In plants, zinc is commonly found bound to proteins. In barley (Hordeum vulgare), major storage proteins are alcohol‐soluble prolamins known as hordeins, and some of them have the potential to bind or store zinc. 65Zn overlay and blotting techniques have been widely used for detecting zinc‐binding protein. However, to our knowledge so far this zinc blotting assay has never been applied to detect a prolamin fraction in barley grains. A radioactive zinc (65ZnCl2) blotting technique was optimized to detect zinc‐binding prolamins, followed by development of an easy‐to‐follow nonradioactive colorimetric zinc blotting method with a zinc‐sensing dye, dithizone. Hordeins were extracted from mature barley grain, separated by SDS‐PAGE, blotted on a membrane, renatured, overlaid, and probed with zinc; subsequently, zinc‐binding specificity of certain proteins was detected either by autoradiography or color formation. The dithizone staining method gave similar reproducibility to the radioactive blotting. The detected zinc‐binding protein was identified as B‐hordein by Western blotting. 相似文献
109.
Sahar Hatami Saeed Zavareh Mojdeh Salehnia Taghi Lashkarbolouki Mohammad Taghi Ghorbanian Isaac Karimi 《Iranian Biomedical Journal》2014,18(3):181-188
Background: Cryopreservation of pre-antral follicles is a hopeful technique to preserve female fertility. The aim of the present study was to evaluate reactive oxygen species (ROS) and total antioxidant capacity (TAC) levels of mouse vitrified pre-antral follicles in the presence of alpha lipoic acid (ALA). Methods: Isolated pre-antral follicles (140–150 µm in diameter) were divided into vitrified–warmed and fresh groups. Each group was subjected to in vitro maturation with or without ALA for 12 days, followed by adding human chronic gonadotropin to induce ovulation. In vitro fertilization was performed to evaluate their developmental competence. In parallel, the amount of ROS and TAC were assessed after 0, 24, 48, 72, and 96 h of culture by 2'',7''-dichlorofluorescin assay and ferric reducing/antioxidant power assay, respectively. Results: The respective rates of survival, antrum formation, and metaphase II oocytes were significantly higher in ALA-supplemented groups compared to the groups not treated with ALA. TAC and ROS levels were significantly decreased and increased, respectively during the culture period up to 96 h in the absence of ALA in both vitrified and non-vitrified samples. However, with pretreatment of ALA, TAC levels were increased significantly and remained constant up to 96 h in vitrified-warmed pre-antral follicles, while ROS levels completely returned to the level of starting point after 96 h of culture in the presence of ALA. Conclusion: Pretreatment of ALA positively influences development of pre-antral follicles in vitrified and non-vitrified samples through increasing follicular TAC level and decreasing ROS levels. Key Words: Vitrification, Pre-antral follicle, Alpha lipoic acid (ALA), Reactive oxygen species (ROS), Total antioxidant capacity (TAC) 相似文献