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651.
Saeid Hazrati Arman Beyraghdar Kashkooli Farhad Habibzadeh Zeinolabedin Tahmasebi-Sarvestani Amir Reza Sadeghi 《Gesunde Pflanzen》2017,69(3):131-137
Application of bio-based edible coatings, which are in line with sustainable agriculture practices, has been a hot topic in recent years. In order to evaluate the effect of Aloe vera L. gel coating, on the store ability of peach fruits, a 30-day postharvest experiment with 10-day sampling intervals was performed. A. vera gel coating had significant positive effects on the weight loss, color change, and sensory evaluation. The amount of weight loss, color change, Total Soluble Solids (TSS) and Titratable Acidity (TA) in coating was lower than control. Furthermore, our results showed that A. vera gel coating can enhance visual properties, and could also lead in more favourable taste and texture. Regarding the obtained results, it can be suggested that A. vera gel coating can enhance the qualitative and quantitative post-harvest traits of fruits, hence, it could be a suitable alternative for chemicals preservative in commercial storage of peach fruits. 相似文献
652.
Abouzar Asadi Alireza Zebarjadi Mohammad Reza Abdollahi Jose M. Seguí-Simarro 《Euphytica》2018,214(11):216
Cucumber is one of the most important vegetable crops worldwide, which makes it a good candidate to produce doubled haploid (DH) lines to accelerate plant breeding. Traditionally, these approaches involved induction of gynogenesis or parthenogenesis with irradiated pollen, which carries some disadvantages compared to androgenesis. Despite this, studies on anther/microspore cultures in cucumber are surprisingly scarce. Furthermore, most of them failed to unambiguously demonstrate the haploid origin of the individuals obtained. In this work we focused on anther cultures using two cucumber genotypes, different previously published protocols for anther culture, different in vitro culture variants to make it more efficient, and most importantly, a combination of flow cytometry and microsatellite molecular markers to evaluate the real androgenic potential and the impact of anther wall tissue proliferation. We developed a method to produce DH plants involving a bud pretreatment at 4 °C, a 35 °C treatment to anthers, culture with BAP and 2,4-D, and induction of callus morphogenesis by an additional 35 °C treatment and sequential culture first in liquid medium in darkness and second in solid medium with light. We also found that factors such as genotype, proliferation of anther wall tissues, orientation of anthers in the culture medium and growth regulator composition of the initial anther culture medium have a remarkable impact. Our rate of chromosome doubling (81%) was high enough to exclude additional chromosome doubling steps. Together, our results present androgenesis as an improvable but yet more convenient alternative to traditional gynogenesis and parthenogenesis-based approaches. 相似文献
653.
Mohammad Reza Hamze Hossein Shariatmadari Bahram Baninasab 《Archives of Agronomy and Soil Science》2018,64(10):1432-1445
A two-year field experiment was conducted to investigate the effects of foliar-applied K in the form of mineral compound (K2SO4) and complexed with lysine (KL) and lysine plus methionine (KLMet) with or without ascorbic acid (A) on nut yield and quality of bearing pistachio (Pistachio vera L. cv. Owhadi). Results showed that foliar application of K, regardless of applied source, significantly increased leaf and nut K concentration in comparison with control. In both experimental years, the trees supplemented with K provided higher total yield, fresh and dry mass of shelled and unshelled 100-nut, and 100-kernel dry mass and lower percentage of non-split shells in comparison with those un-supplemented with K. In both years, foliar application of K significantly decreased the percentages of blank nuts. The effectiveness of K-amino chelates in improving nut yield and quality was, in general, higher than that of K2SO4. The highest yield and the best nut quality was obtained with foliar application of KLMet-1. The critical leaf and nut K concentration for optimum pistachio nut yield and quality was 2.27 and 1.87%, respectively. Foliar application of K particularly in the form of KLMet-1 during nut filling is recommended to obtain optimum yield and quality of pistachio. 相似文献
654.
Razieh Babapour Ismael Ghajar Reza Ghodsi 《Scandinavian Journal of Forest Research》2018,33(2):178-187
Earthwork operations accounted for great amount of forest road construction costs. Any Optimization in planning road profile needs a reliable objective function that calculates earthwork volume in an appropriate time and accuracy. This study aimed at incorporating the shape of the ground cross sections in calculating cut/fill areas using three alternative methods including: Multiple Linear Regression (MLR), Artificial Neural Network (ANN) and heuristic programming in MATLAB environment. The accuracy of results was validated via AutoCAD as a manual method for area calculation of road’s cross-section. Trapezoidal method applied to calculate the area of cut/fill in the heuristic method. Paired sample T-Test and statistical analysis (ANOVA) with confidence level of 0.95 indicated that the heuristic method not only reduced computing time but also provided accurate estimations as same as the manual AutoCAD based method. It can be concluded that although MLR and ANN estimations were as well as AutoCAD results within a reasonable time, they need to be retrained by adding, removing or changing entrance parameters. 相似文献
655.
Moslem Papizadeh Anne D. van Diepeningen Hamid Reza Zamanizadeh Farkhondeh Saba Hossein Ramezani 《European journal of plant pathology / European Foundation for Plant Pathology》2018,151(3):689-701
Two Fusarium strains, isolated from Asparagus in Italy and Musa in Vietnam respectively, proved to be members of an undescribed clade within the Fusarium solani species complex based on phylogenetic species recognition on ITS, partial RPB2 and EF-1α gene fragments. Macro- and micro-morphological investigations followed with physiological studies done on this new species: Fusarium ershadii sp. nov can be distinguished by its conidial morphology. Both isolates of Fusarium ershadii were shown to be pathogenic to the monocot Asparagus officinalis when inoculated on roots and induced hollow root symptoms within two weeks in Asparagus officinalis seedlings. In comparison mild disease symptoms were observed by the same strains on Musa acuminata seedlings. 相似文献
656.
Amir Zarrabi Jafar Yasrebi Abdolmajid Ronaghi Reza Ghasemi Fasaei Abdolmajid Sameni 《Arid Land Research and Management》2018,32(2):170-183
Zinc (Zn) is an essential micronutrient for crop growth. This metal can be found in chemical forms or fractions in the soil. The objective of this study was to investigate the distribution of Zn in special chemical forms using the sequential extraction method after treating eight calcareous soils by zinc sulfate and municipal solid waste (MSW) compost. Zn was separated in seven defined forms as exchangeable (Ex), carbonate (Car), organic (Om), manganese oxide bound (MnOX), amorphous iron oxide bound (FeAOX), crystalline iron oxide bound (FeCOX), and residual (Res). According to the results, the mean concentrations of Zn in chemical forms in untreated soils from higher to lower were 31.84, 8.13, 2.64, 2.57, 0.45, 0.39, and 0.16?mg?kg?1 for the Res, FeCOX, Car, FeAOX, Om, MnOX, and Ex forms, respectively. The total applied Zn to the studied soils from both the sources of zinc sulfate and MSW compost after incubation for 30 days was converted to chemical forms in the following order: Car?>?Res?>?FeCOX?>?Om?>?FeAOX?>?MnOX?>?Ex. On average, 30.3% of total Zn from zinc sulfate and 28.8% of total Zn in the MSW compost were converted into the Car form. The high content of calcium carbonate (CaCO3) in the studied soils is an important factor affecting the conversion of Zn forms, mostly in the Car form through the application of both the inorganic and the organic sources of Zn. 相似文献
657.
Arash Mohammadzadeh Javad Vafabakhsh Abdolmajid Mahdavi Damghani Reza Deihimfard 《Archives of Agronomy and Soil Science》2018,64(7):967-982
In the present study, environmental effects of carrot, tomato, potato and onion production systems were evaluated using the quantitative indices of energy efficiency, global warming potential (GWP), economic indicators, pesticide risk (field environmental impact quotient – FEIQ), tillage impact (TI), fertilizer, land and water use efficiency, and the eco-efficiency index (ratio of gross production to environmental impact for GWP, FEIQ and TI). Data was collected from 110 farmers by survey to determine crop production in the region. The results showed that the energy index for the potato production system was the most efficient; however, the carrot production system was the best in terms of the economic and environmental indices of GWP, FEIQ and TI. For irrigation water productivity (IWP) and land production efficiency (LPE), the potato production system was superior. The carrot production system had the highest values for economic irrigation water productivity (EIWP), economic land production efficiency (ELPE) and phosphorous and potassium use efficiency. The tomato production system recorded the lowest nitrogen use and highest nitrogen use efficiency. It can be concluded that the onion production system was furthest from sustainability goals based on the aforesaid indices. 相似文献
658.
Mansour Karkon Varnosfaderani Rasoul Kharazmi Aliakbar Nazari Samani Mohammad Reza Rahdari Seid Hamid Matinkhah Nasrollah Aslinezhad 《林业研究》2017,28(1):145-153
The status of woody plants in dry-land systems is a fundamental determinant of key ecosystem processes. Monitoring of this status plays an important role in understanding the dynamics of woody plants in arid and semi-arid ecosystems. The present study determined the dynamism of the Zagros forests in Iran using Remote Sensing and Geographic Information System techniques and statistical science. The results show that the density of trees varied from 10 to 53 % according to the physiographic and climatic conditions of semi-arid regions. The best and lowest correlation between vegetation indices and forest density were obtained for the global environmental monitoring index (GEMI; R 2 = 0.94) and soil adjust vegetation index (R 2 = 0.81), respectively. GEMI is used to monitor land use changes over a 10-year period. Results show that 2720 ha2 of forest have been destroyed by human interference and tillage on steep slopes during this period which also resulted in the loss of the fertile soil layer. GEMI determined the areas with a biomass of trees and could normally separate border regions with low biomass density of trees from regions without canopy cover. The results revealed that assessment of forest and vegetation cover in arid and semi-arid arduous forest regions using satellite digital numbers and ordinary sampling is subject to uncertainty. A stratified grouping procedure should be established to increase the accuracy of assessment. 相似文献
659.
Vermicompost can have an effective role in plant growth and nutrition. It can also reduce the harmful effects of stress caused by environmental factors. This study was a factorial experiment with a completely randomized plot design and three replications. The results showed that the calcium concentration (+40% +39%) of root and calcium (+71% +67%) and potassium contents (+49% +59%) of leaf under conditions of moderate and severe water stress increased under vermicompost treatments at the ratio of 30%. Sodium absorption (?37% ?21%) in moderate and severe conditions was significantly reduced by vermicompost treatment. In moderate and severe water stress, the growth medium of 30% vermicompost significantly enhanced proline (+39%) and soluble protein content (+28%) compared to the control. In conclusion, our results proved vermicompost fertilizer due to its structural properties and components, served to reduce the negative effects of water stress by increasing the absorption of calcium (Ca) and potassium (K), and decreasing sodium (Na) absorption that resulted in increased evaluations for proline and protein content. 相似文献
660.
Nanofertilizers, which supply nutrients to the plant, are used to replace conventional fertilizers. Iron (Fe) is one of the essential elements for plant growth and plays an important role in the photosynthetic reactions. To study the effects of nano-iron fertilizer on Catharanthus roseus, plants were treated with different concentrations (0, 5 10 20, 30, and 40 mM) of iron oxide nanoparticles (Fe2O3) for 70 days. Fe2O3 nanoparticles increased growth parameters, photosynthetic pigments, and total protein contents in the treated plants significantly. The maximum amounts of growth parameters, photosynthetic pigments, and protein contents were obtained with 30 µM Fe2O3 and minimum values of these parameters were found with 0 µM Fe2O3. The highest value of total alkaloid content was obtained in 0 µM Fe2O3 and the lowest value was observed in control plants. Iron oxide nanoparticles increased potassium, phosphorus, and iron absorption but did not show a significant effect on sodium content. 相似文献