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1.
Inter-simple sequence repeat (ISSR) markers were used to study phylogenetic relationships among 33 citrus genotypes including several undefined local or native varieties as well as some known varieties in the Fars Province of Iran.  相似文献   
2.
Strawberry cultivar ‘Selva’ was grown in a hydroponic culture in a heated greenhouse to study the effects of supplementary potassium (K) added to nutrient solution and applied to the plants grown at high sodium chloride (35 mmol/L) concentration. Treatments were: (1) nutrient solution alone (N); (2) N + sodium chloride (NaCl) (35 mmol/L) (NS); (3) N + NaCl + potassium sulfate (K2SO4; 5 mmol/L) (NSK1); (4) N + NaCl + K2SO4 (10 mmol/L) (NSK2). Leaf area, biomass production, and gas exchange variables (Pn, E, gs, Ci) negatively affected by salinity. In addition, ionic concentrations (sodium, chlorine, and potassium) increased by salinity treatments. Supplementary potassium had positive effects to ameliorate the harmful effects of NaCl on leaf area. Shoot growing was decreased by potassium (K) application. Ionic concentrations of this cultivar show contradictory results. Although supplementary potassium increased K accumulation, but sodium (Na) and chlorine (Cl) concentrations of plant parts was increased. These results show that potassium can be applied for this cultivar in salinity conditions.  相似文献   
3.
Pot experiment was conducted in a greenhouse to compare the effect of four organic substrates [S1: Persian turpentine trees leaf mold (50%) + Soil (50%); S2: Oak leaf mold (50%) + Soil (50%); S3: Cypress leaf mold (50%) + Soil (50%) and S4: liquorice processing wastes (50%) + Soil (50%)] application on strawberry growth, yield, and nutrient concentration, and on some soil properties. Results showed that leaves mold and liquorice wastes application decreased pH, increased soil organic matter, and increased soil concentrations in all mineral elements studied, except for potassium (K). The amount of mineral elements in substrates had also a great influence on the leaf nutrient concentrations. High levels of nitrogen (N), K, iron (Fe), manganese (Mn), and zinc (Zn) were obtained in leaves; while phosphorus (P) concentration was lower than sufficient levels. Although, strawberry fresh and dry weights and leaf chlorophyll content were significantly higher in plants grown in S4 with no added fertilizer, the highest fruit yield was obtained in combination substrates with 50% fertilizer. Our results indicate that use of leaf mold and liquorice wastes in soil mixtures can reduce the amount of fertilizer required for optimum strawberry plant growth and yield.  相似文献   
4.
ABSTRACT

The purpose of this study is to investigate the effect of cellulosic wastes and nanoscale zero-valent iron (nZVI) on the soil properties and the nutrient uptake by Quercus castaneifolia C.A.Mey seedlings. The seedlings were planted in pots (unpolluted soil) and cadmium (Cd) was added to the pots in three concentrations (10, 20, 30?mg.kg?1). Cellulosic wastes were mixed with the soil (at the same time as the planting) in four levels (W: 0, 10, 20, 30?g.100g?1 soil). The reduction method was used to prepare nZVI, then the nanoparticles were injected into the polluted pots in four levels (N: 0, 1, 2, and 3?mg.kg?1). The lowest concentration of Cd in leaves, stems and roots and for all the contamination levels was observed in N3. All the cellulosic wastes and N3 significantly increased the soil pH at all the levels of contamination. An increasing trend of the soil carbon (C) content was observed by adding the cellulosic wastes. The highest pH and C content were observed in W3. The lowest bioavailable Cd contents for all the contamination levels was observed in N3. According to the results, nZVI and cellulosic wastes could help the plants establishing in heavy metal-polluted lands.  相似文献   
5.

Livestock presence in forest ecosystems is considered a factor in forest destruction in developing countries; therefore, rehabilitation practices following livestock exclusion could be a good way to restore forests. The main purpose of this study was to investigate the changes in the soil properties and plant biodiversity 12 years after applying fencing and planting in the livestock farms in the Hyrcanian Forests of Iran. First, three regions close to each other were selected and then four areas (treatments) were considered in each region: 1. An area under livestock use (L), 2. an enclosed area (E; with fences, established in 2007), 3. a planted area (P; established with Acer velutinum seedlings in 2007), and 4. a control area (C; natural forest); therefore, a total of 12 areas were considered. In each of the 12 areas, three plots (20?×?20 m) were randomly established (a total of 36 plots), and all the vascular plants in the herbaceous layer and woody species seedlings were recorded in order to study the biodiversity of the vegetation cover. One soil sample was taken from each plot to examine the physical and chemical properties of the soil. The results showed that bulk density, pH, electrical conductivity (EC), and available potassium were not significantly different between the C, E, and P treatments. Rehabilitation practices improved the soil pH (P: 6.36?±?0.06, E: 6.59?±?0.08), EC (P: 0.86?±?0.05, E: 0.82?±?0.04 ds cm?1), total nitrogen (P: 0.31?±?0.001, E: 0.31?±?0.005), available phosphorus (P: 10.13?±?2.22, E: 19.29?±?2.43 mg kg?1), and available potassium (P: 1369.60?±?31.06, E: 1898.80?±?448.60 mg kg?1). The Margalef index was lower in the L area and no significant difference was observed between the E and P areas. Since the multivariate analysis (based on the vegetation and soil data) showed that P and E had more similarity to C, these treatments could accelerate the forest restoration process.

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6.
Effects of 0, 10, 20 and 30 ppm N6Benzyladenine and 1, 2 and 3 applications on a summer variety of potato were studied in a factorial experiment. Benzyladenine at 10–20 ppm regardless of the number of applications significantly increased number of shoots per plant. This was noticed as early as 20 days after the first application. Two applications regardless of concentration, and a combination of two applications and 20 ppm concentration significantly increased the total length of main shoots. There were no significant changes in tuber production.  相似文献   
7.
An experiment was conducted with non-irrigated vines (Vitis vinifera), in which the number of buds per cane and the number of canes per vine were varied. With increasing canes per plant the percentage bud-burst decreased. Cluster number and total yield increased with increasing the number of buds per vine. Cluster weight and sugar content decreased when vines were overloaded. Yield was positively correlated with cluster number and negatively correlated with sugar content. The position of the pruning-cut affected the percentage bud-burst only near the cut.  相似文献   
8.
Summary

Flower-induction is the event that initiates the transition of a vegetative apex into a floral apex in response to an environmental or developmental cue. Under flower-inducing conditions, biochemical or physiological changes can be recognised. One possible change that could occur is in sugar content. In this study, levels of non-structural carbohydrates (e.g., sucrose, glucose, fructose and starch) were measured in shoot tips, leaves and roots of strawberry (Fragaria ananassa cv. ‘Kordestan’) under flower bud-inducing conditions, and compared with non-induced plants. Runner plants were potted and grown for 4 weeks under non-inducing conditions (31º/25°C day/night; 16 h daylength). Half of the plants were then put under flower-inducing conditions (25°/15°C day/night; 8 h daylength) for 3 weeks. Samples for carbohydrate analysis were taken from induced and non-induced plants every 3 d over 3 weeks, and sucrose, glucose and fructose contents were determined by HPLC, and starch concentrations by the anthrone method. The most abundant soluble sugar, in all organs tested, was sucrose. Sucrose levels in shoot tips and leaves decreased at the beginning of the induction treatment, but soon increased to the levels recorded in non-induced plants. Fructose increased markedly in shoot tips of induced plants 3 d after the start of the short-day treatment, and declined thereafter. Starch contents in shoot tips, leaves and roots of non-induced strawberry plants were higher than those in induced plants on most sampling dates. From the results of this study, it appears that soluble carbohydrate contents in different organs of June-bearing strawberry may have a decisive role on flower-bud induction.  相似文献   
9.
Summary The effect of foliar sprays of 0, 25, 50 and 75 ppm potassium gibberellate (KGA) and 1, 2 and 3 applications were studied on an economically important summer variety of potato (Eslamboli) in a factorial experiment. Three applications of KGA regardless of concentration significantly increased the number of tubers and the total length of main stems over 1 and 2 applications. Soluble solids content of tubers significantly decreased with each unit increase in number of applications regardless of concentration. A combination of 3 applications at 25 ppm caused the largest significant increase in total length of main stems. Mean length of main stems also significantly increased when the concentration, number of applications or their combination were considered. Treated tubers appeared smaller than controls. There were no changes in mean fresh weight of each tuber, dry matter percentage, number of main stems or total yield.
Zusammenfassung In einem faktoriellen Versuch wurden die Einflüsse von Kalisalz der Gibberellins?ure (KGA) bei Gaben von 0, 25, 50 und 75 ppm und bei 1, 2 und 3 Anwendungen auf die vegetative Entwicklung und die Knollenerzeugung einer ?konomisch wichtigen Sommerkartoffelsorte (Eslamboli) untersucht. Der Versuch wurde als Split-plot mit 4 Wiederholungen angelegt. Die Knollen wurden am 1. April 1971 ausgepflanzt. Die erste Spritzung wurde 4 Wochen nach dem Auspflanzen, als die Stengel 10–12 cm lang waren, vorgenommen. Die weiteren Spritzungen folgten in je 10 Tagen Abstand. Das vegetative Wachstum wurde alle 10 Tage an den vierten, achten und zw?lften Pflanzen in der Reihe der 14 Pflanzen gemessen. Die Knollen wurden am 10. August 1971 geerntet und die notwendigen Messungen daran vorgenommen. Drei Anwendungen von KGA, gleichgültig welcher Konzentration, erh?hten in signifikanter Weise die Anzahl der Knollen, und die Gesamtl?nge der Haupttriebe gegenüber von nur einer oder zwei Anwendungen (Tabelle 1, Abb. 2). Der Gehalt an l?slichen Inhaltsstoffen der Knollen verminderte sich signifikant mit jeder zus?tzlichen Behandlung ohne Rücksicht auf die Konzentration (Tabelle 1). Die Kombination von 3 KGA-Anwendungen zu 25 ppm brachte die gr?sste signifikante Zunahme in der Gesamtl?nge der Haupttriebe (Tabelle 2). Bei zwei und drei Anwendungen von KGA, gleichgültig welcher Konzentration, nahm die durchschnittliche L?nge der Haupttriebe im Vergleich zu einer Behandlung signifikant zu (Tabelle 1, Abb. 3). KGA zu 25–50 ppm, ohne Rücksicht auf die Zahl der Anwendungen, brachte eine signifikante Zunahme der durchschnittlichen L?nge der Hauptstengel (Tabelle 3). Die Kombination von 3 Spritzungen mit KGA zu 50 ppm zeitigte die gr?sste signifikante Zunahme in der durchschnittlichen L?nge der Haupttriebe (Tabelle 4). Knollen von behandelten Pflanzen waren kleiner als die der Kontrolle (Abb. 1). Es ergaben sich keine signifikanten Aenderungen in der Anzahl der Haupttriebe, in Prozent der Trockensubstanz der Knollen, im durchschnittlichen Frischgewicht jeder Knolle und im Gesamtertrag der Knollen.

Résumé Les auteurs ont étudié dans une expérience factorielle les effets de gibbérellate de potassium (KGA) à 0, 25, 50 et 75 ppm et 1, 2 et 3 applications sur le développement végétatif et la production de tubercules d'une variété économiquement importante (Eslamboli). Ils ont utilisé la méthode des blocs avec répartition des parcelles au hasard et 4 répétitions. La plantation eut lieu le ler avril 1971. La première pulvérisation fut effectuée 4 semaines après la plantation, au moment où la longueur des tiges était de 10–12 cm environ, et les pulvérisations étaient répétées après chaque période de 10 jours. La mesure du développement végétatif a été faite chaque dixième jour sur la quatrième, huitième et douzième plante dans la ligne de 14 plantes. La récolte des tubercules s'est faite le 10 ao?t 1971 et on a effectué sur ceux-ci les mensurations nécessaires. Trois applications de KGA, indépendamment de la concentration, accroissent significativement le nombre de tubercules et la longueur totale des tiges principales par rapport à 1 ou 2 applications (tableau 1, fig. 2). La teneur des tubercules en éléments solubles diminue significativement avec chaque augmentation du nombre d'applications, indépendamment de la concentration (tableau 1). La combinaison de 3 applications et de la dose de 25 ppm entra?ne l'augmentation la plus significative de la longueur totale des tiges principales (tableau 2). Deux et trois applications de KGA indépendamment de la concentration augmentent significativement la longueur moyenne des tiges principales par comparaison avec une application (tableau 1, fig. 3). Le KGA à 25–50 ppm, indépendamment du nombre d'applications, augmente significativement la longueur moyenne des tiges principales (tableau 3). La combinaison ‘3 applications de KGA à 50 ppm’ a provoqué l'accroissement le plus significatif de la longueur moyenne des tiges principales (tableau 4). Les tubercules traités se sont révélés de volume inférieur à ceux des témoins (fig. 1). Aucun changement significatif n'est apparu dans le nombre de tiges principales, le pourcentage de matière sèche des tubercules, le poids moyen frais de chaque tubercule et la production totale de tubercules.
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10.
Girdling, growth retardant succinic acid 2-2-dimethyl hydrazide (Alar), 2-naphthoxyacetic acid (NOA), and Gibberellic acid (GA3) were tested as a fruit-setting agent in 1975 for ‘Yaghooti’, a stenospermocarpic cultivar of Vitis vinifera grape. Bloom Alar spray at 7500 p.p.m. increased the number of berries per cluster and the cluster weight. Bloom auxin spray did not effectively increase fruit set, while gibberellin had a depressing effect. Girdling also increased fruit set and a combination of Alar and girdling had the most pronounced effect on fruit set. None of the treatments significantly altered soluble solids and/or vitamin C content of the berries.  相似文献   
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