جستجوی مقالات مرتبط با کلیدواژه « Density » در نشریات گروه « باغبانی »

Datura stramonium L. is one of the important medicinal plants in the pharmaceutical industry due to its alkaloid compounds. To investigate the effects of urea fertilizer at three levels (60, 120, and 180 kg.ha-1) and planting density at three levels (6, 10, and 14 plants.m-2) on the yield and yield components of this plant species, a factorial experiment was conducted in a randomized complete block design in the research farm of Isfahan Agricultural and Natural Resources Research and Education Center, Iran in 2018 and 2019 crop years. The main effects of density and urea on the traits including height, number of lateral branches, and 1000-seed weight and the interaction of different urea and density levels on the traits including seed yield, biological yield, number of capsules per plant, number of seeds per plant, and number of seeds per capsule were significant in both years. The highest seed yield (1282.37 and 1212.53 kg.ha-1, respectively in 2018 and 2019 years) was obtained in the urea fertilizer 180 kg.ha-1 and 6 plants.m-2 treatment. The causal analysis results showed that the highest direct positive effect at the different levels of density and urea was related to the number of capsules per plant. The results of this experiment showed that the application of 180 kg.ha-1 of urea and 6 plants.m-2 could play an important role in increasing the seed yield of medicinal plant D. stramonium.

In order to investigate of the effects of topic and granstar herbicides with codacide adjuvant to weeds control of wheat fields an experiment was carried outwith 13 treatment and 4 replication  in 2012-2013, in Karaj. Experiment factor were granstar herbicide 3 dose (14,17,20 g/ha), granstar herbicide (14,17,20 g/ha+0.25% V/V Codacide) and topic herbicide(0.6,0.8,1 lit/ha) and topic herbicide (0.6,0.8, 1 lit/ ha+ 0.25% V/V codacide). These treatments were used in tillering time. The result of this experiment indicated that Granstar 17 gr/ha+ 0.25% herbicide had the best of effect on weed control.

In order to determine the critical period for weed control of greenhouse cucumber, an experiment was conducted in 2012 in a soil greenhouse located 25 km from Mashhad, as a randomized complete blocks design with three replications. The experiment consisted of two treatment series of weed interference. The first series consisted of weed-interference periods (including 14, 28, 42, 56, 70 and 84 days after emergence and the entire growth period of greenhouse cucumber) and the second series consisted of weed-free periods (including 14, 28, 42, 56, 70 and 84 days after emergence and the whole period of greenhouse cucumber growth). Results of this study showed that red root pigweed, common purslane, black nightshade, dwarf mallowand and common lambsquarters were the weeds with the highest density and biomass. Increasing or decreasing the weed-interference and weed-free periods led to changes in density, biomass, relative density and relative biomass of these plants. If 10, 5, and 1% of greenhouse cucumber yield loss are acceptable, then weed control must be carried out from 23 to 77 days (54 days), 18 to 94 days (76 days), and 16 to 107 days (91 days) after the greenhouse cucumber emerges, respectively. In general, the results of this experiment demonstrated that weed control in greenhouse cucumber production is necessary to achieve optimal yield.

In order to evaluate the effect of plant density on quantitative and qualitative yieldof three species of Thymus under dry farming conditions in Tehran (Damavand), Kurdistan and Kermanshah provinces, an experiment was conducted in a randomized block design based on split plot with three replications during three years (2009-2011). The treatments were included three species (T. vulgaris L., T. daenensis Celak.and T. kotschyanus Boiss. & Hohen.) and three planting densities (4, 6 and 8 plant/m2), which were considered as main and sup-plots, respectively. Shoot dry matter yield, essential oil content, yield and essential oil components were determined. Results showed that the four-interaction effect (density, species, year and province) was significant on dry matter content, calculated to be from 75 to 5172 kg/h in different treatments. The maximum dry matter yield was observed at a density of 6 plant/m2 for T. daenensis in Kermanshah in the third year of experiment. The highest essential oil yield was obtained at a density of 8 plant/m2 for T. daenensis in Kermanshah in the second year of experiment. The maximum thymol content (80.33%) was related to T. daenensis inDamavand at a density of 6 plant/m2 in the third year of experiment. Overall, high production capacity of T. daenensis in the study provinces indicates the adaptation and economic yield of this native and valuable species.

The maintenance of the quality of fresh produce is still a major challenge for the consumers. The most important qualitative attributes contributing to the marketability of fresh fruit a reappearance, color, texture, flavor, nutritional value and microbial safety. Storage conditions of product after harvest and storage duration are important factors with specific effect on products qualitativeproperties such as acidity, soluble solids materials, phenolic compounds and density. The amount of soluble solids materials is an important qualitative factor that is directly related to fruit quality and ripening.The existence of phenolic compounds, phenol absorption and changes phenol in product has caused changes in color. Shape, size, arithmetic mean diameter, geometric mean diameter, mass, volume, density, and sphericity coefficient are some of the physical properties of products that are crucial to analyze the behavior of matter in the handling.Furthermore, adequate knowledge about the physical properties of the products is of high importance in machines design, transportation and processing of product.
In this study, two types of olives, which were bitter and sweeten with 1.5%NaOHbefore the storage, were collected and their physical properties (length, width, thickness, arithmetic and geometric mean diameter, sphericity coefficient, mass, volume, density and primary moisture) were evaluated. Then, tostudy the effect of storage duration,the sweetened olives were stored at two temperatures (25℃ and 4℃temperature of the refrigerator) for 3 months,and during this period, sampling was performed at 10-dayintervals and the amount of total acidity (TA was determined by diluting each 1 ml aliquot of strawberry juice in 10 ml distilled water and then titrated to pH 8.1 using 0.1 N NaOH), total soluble solids materials (TSS was determined by a handheld refractometer device and expressed as ° Brix), phenolic compounds and the density weremeasured. The study was carried out as factorial based oncompletely randomized designwith twoindependent factors of temperature and storage time.
Results obtained for physical properties showed that the means of length, width andthickness insweet olive were 9.72, 1.34 and 1.11%respectivelyhigherthan bitter type. Penetration and absorption of NaOH and processing methods of the product can be considered among the possible causes of this increase. Linear regression relations between physical properties for sweet and bitter olives showed that mass and volume of fruit areestimated accurately according to the main dimensions. The results of data variance analysis also showed thatdensity and soluble solids materialswere significantly affected by themain and interaction effects of the twofactors at 1% probability level. Moreover, the main effect of storage time on total acidity and phenolic compoundswassignificant at 5% and 1% levels, respectively. With increasing storage time, density of sweet olive increased and soluble solids materials and phenolic compounds decreased. Acidity changes of olive during storage fluctuated, and an increase was found in the values of density and soluble solids materials along with theincrease of storage temperature from 4℃ to 25℃.With respect to density, the third month of storage showedhigherincrease compared toother months, and maximum value was reported for sweet olive in temperature of 25℃ and 19thday. Increase ofstorage duration resulted in the reduction of moisture content,whichin turns leads to the reductionof product volume and increase of density. The reductionfound in acidity in the second and third months of storage resultedfrom maturation and ripening processes of the fruit. Organic acids are a source of energy,which are consumed in the time ofmetabolism increaseand fruit ripening.Decreasein phenolic compounds also occurs as the result ofphenol penetration from olive flesh into the water - salt solution.
Results of this study showed that length, width, thickness, mass and volume of sweet olive weregreaterthan bitter type, but,by contrast,sphericity coefficient was higher in bitter olive. Moreover, storage time, increase caused an increase in thedensity of sweet olive and decrease insoluble solids materials and phenolic compounds.There was fluctuation inacidity during different storage times. An increase was found in the values of density and soluble solids materials along with the increase in storage temperature from 4℃ to 25℃.

In order to study the effect of different densities on the quantitative and qualitative characters of the two cultivars of alfalfa in condition of Alley Cropping system an experiment was done in the experimental field of Agriculture College¡ Karaj unit in the years 1388-1389. It was done in the form of split factorial in randomized complete block designin two rep.The treatment were: two cultivars (Hamedani alfalfa and ghare alfalfa)¡ and five density(5¡10¡15¡20¡25 kg/ha)¡ and three harvest¡ in thisexperiment cultivars were main plot¡ density and crop were sub plot. The measured character included the percentage of Crude protein of leaf and steam¡leaf and steam Fiber¡ Fresh weight¡ Dry weight and total yield protein. The results corresponding to the analysis of variance showed that the interaction of density had a significant effect on crud protein of steam at= 1% and had a significant effect on steam fiber at p=5% .The result of mean contrast of stages effect showed that the stages had a significant effect on other character at p=1%. The interaction of density* stage had a significant effect on leaf total fiber at p=5%.The result corresponding to the analysis of variance showed that the interaction of density on crude protein of steam in density levels 4 and 5 were about 12/97¡ 12/81had highest means and levels 1and 3 had the least percentage. Total fiber in steam was oposite¡level 1 had the least. Also stage three had highest percentage of crud protein of leaf (32/06) and steam about (14/28).The stage two had the least percentage of crud protein leaf and steam (25/41)¡(12/6). Highest fresh weight was in stage three(4782/8 kg/ha) and stage one had the least fresh weight and dry weight (2270/6 kg/ha)¡(668/41). The highest dry weight was in stage two it was about (1509/88 kg/ha). Moreover the highest and lowest proteinyield corresponding to the second stage(293/35) and first stage (140/56). Stage effect showed first stage had highest Fiberpercentage of leaf (27/64) and steam (41/18).

In order to study the effect of irrigation interval, Nitrogen (N) fertilization and plant density on yield and yield components of fenugreek (Trigonella foenum-graecum L.), a split-split-plot experiment was conducted in Darmian, Iran in Spring 2010 based on a randomized complete block design with three replications. The main plots were irrigation interval at two levels of 5 and 10 days. The sub-plots were N fertilization at three rates of 0, 75 and 150 kg N.ha-1 from urea source and the sub-sub-plots were plant density at three levels of 22, 33 and 66 plants.m-2. According to the results of analysis of variance, irrigation interval significantly affected traits of pod length and water use efficiency (WUE) for seed and biomass production. In addition, main branch number per plant, pod length, seed yield, chlorophyll index and WUE for seed and biomass production, were significantly affected by nitrogen rate and plant density had significant effect on main branch number per plant and ring diameter. Means comparison showed that as irrigation interval was increased from 5 to 10 days, pod length decreased 8.7%, but WUE for seed and biomass production increased 40.5 and 47.5%, respectively. Also, as N rate was increased from 0 to 150 kg N.ha-1, main branch number per plant, pod length, seed yield, chlorophyll index and WUE for seed and biomass production increased by 23.5, 26.4, 23.2, 67.1, 72.3 and 71.5%, respectively. Moreover, with increasing of density from 22 to 66 plant. m-2, branch number per plant and ring diameter decrased 7.9 and 11.2%, respectively. In total, given the results of the study and the importance of water saving, it is recommended to use irrigation interval of 10 days with the application of 150 kg N.ha-1 and density of 66 plants.m-2 for the cultivation of fenugreek in Darmian, Iran.

In order to evaluate the morphological and agronomical traits of linseed (Linum usitatissimum L.) genotypes in different plant densities، a field experiment was conducted as a factorial experiment in RCBD design with three replications in the field. Plant densities of 300، 500، and 1000 plant/m2 as first factor and four linseed genotypes (Iran، Australia، Canada، and France) as second factor were used. Plants were harvested at three stages of vegetative growth، 50% flowering، and maturity stage. Results showed that plant densities had significant effect on plant height and above-ground dry weight in vegetative stage; plant height، stem diameter and dry weight in 50% flowering; and plant height، stem diameter، stem branch number، and dry weight in maturity stage. In addition، the number of capsules per plant، 1000 seeds weight، grain yield and harvest index were significantly affected by plant densities. Different linseeds genotypes showed significant effect on the characteristics of plant height، stem diameter، and stem branch number، in all three harvest stages. Traits as number of capsules per plant، number of seeds per capsule، 1000 seeds weight، grain yield، harvest index، and 50% of flowering and maturity also were affected significantly by linseeds genotypes. The maximum grain yield was obtained in the density of 1000 plants/m2. Maximum values were recorded for Iranian linseed genotype with an average production of 6. 40 seeds per capsule، an average production of 1375 kg of seeds per hectare، and a mean harvest index of 21. 23. It was also identified as the latest genotype for both days to 50% flowering (65 days) and days to maturity (123 days).

The effects of density and intercropping of safflower (Carthamus tinctorious L.) and rocket sativa (Eruca sativa L.) were evaluated on yield and land equivalent ratio. The experiment was conducted as spilt plot in a randomized complete block design with three replications for one year (2010-11) in the experimental field of Share-Rey University. Main plots included three density levels (40، 20 and 16 plantm2) and subplots included six intercropping arrangement system. CCCCCCCC (pure culture of Carthamus tinctorious L.) EEEEEEEE (Pure culture of Eruca sativa L.) and CCCCEEEE، ECCCEEEC، CCEECCEECC، CECECECE (Mix culture). The studied characteristics included yield، yield components and LER. According to the results، the highest dry matter yield (1035 and 1050 gr) and seed yield (246 and 268 gr) were obtained from a density of 40 and CCCCEEEE arrangement for Eruca sativa and Carthamus tinctorious، respectively. In addition، the highest LER of dry matter yield (1. 41) and seed yield (1. 48) were obtained from high density and CCCCEEEE arrangement، indicating the benefits of intercropping as compared to the pure culture of each studied species

This research was carried out to investigate the effect of different levels of potassium (in nutrient solution)، harvest season and plant density on yield and quality of strawberry cv. Selvain hydroponic system conditions. The tests were done in the greenhouse، and laboratories of horticultural science department of the university colleg of agriculture and natural Resources of Tehran University. Throghout the research، there were evaluated the effects of four levels of potassium at concentrations of 1. 5، 2. 6، 3 and 4. 5 meq/L. The control consisted of half strength Quick nutrient solution (2. 6 meq/L potassium). Three plant densities (12، 16 and 20 plants/m2) and two harvest seasons (winter and autumn) were considered in a completely randomized block design of three replications as regarded yield and fruit quality of strawberry cv ''Selva''. The main difference among solutions was observed in their potassium concentrations. Results revealed that، increasing potassium level in nutrient solution up to 3 meq/L caused an increase in TSS، TA، Vitamin C content and fruit potassium content، i. e. level of fruit potassium increased with increase nutrient in solution of potassium from 2. 6 to 4. 5meq/L. Planting densities of 12، 16 and 20 plants/m2 did not affect yield and fruit quality. The effect of harvest season (autumn as compared with winter) was more pronounced on some fruit characteristics such as TSS/TA. However yield، TSS and TA were low in autumn harvest. According to the obtained results، modified Quick nutrient solution with 3meq/L of potassium became known as the most proper solution، but different plant densities did not exhibit any significant differences.

In order to effect of weeds relative time of emergence on single cross 704 Corn (Zea mays) yield was studied in different density levels of the mentioned weed. The experimental design was split plot based on Randomized Completed Block Design (RCBD) with three replications in 2012 was carried out in Koohdasht, Lurestan. The emergence time was considered in 3 levels of E1, E2 and E3 (emergence of the weed 14 days earlier, 7 days earlier and simultaneously with corn, respectively) as main plots and density of weed in 6 levels of D1, D2, D3, D4 and D5 (0, 4, 8, 12, 16 and 20 plants per m2, respectively) as subplots. The height, laef area index (LAI) of corn decreased with earlier emergence time and increasing the density of the Weeds. Also, earlier emergence time of weeds at high densities lead to the reduction in yield component (ear length, diameter and weight, number of seed row in ear, number of seed in row and thousand seed weight). The results showed that a decreasing in grain and biological yield of Corn, as the emergence time of Corn delayed in comparison with the emergence time of weeds. The maximum reduction in grain and biological yield of Corn was observed in 14 days earlier emergence of weeds compared to Corn in high density of this weed (20 plants per m2) with 100 and 99 percent respectively, as Corn plants were put in canopies of weeds plants. Totally, based on the results of this research it can be stated that as the number of the earlier emergence days of weeds compared to the Corn increase, the competitive potential of the Corn reduces and an intense decrease is being observed in its yield. Though, the increase in density of the weed resulted in grain and biological yield reduction, there was no difference between the process of reduction in high densities of weed.

Summer savory (Satureja hortensis L., Lamiaceae) is a well known medicinal and aromatic plant, native to Southern Europe, Anatolia, Caucasus, Iraq and western Iran, but nowadays it is cultivated worldwide. In order to evaluate the effect of sowing date and plant density on the yield and morphological characteristics of Satureja hortensis L. a field experiment was conducted in Sary Agricultural University using split-plot design based on randomized complete blocks with three replications during 2010. Main factors were three sowing dates (11 April, 22 April and 3 May) and sub factors were three plant density (15×35, 25×35 and 35×35cm). The species were investigated at full flowering stage. Sowing date and plant density had significant effects on most of the morphological characteristics. According to the results of mean comparison, the highest plant height (52.3 cm), lateral shoot (23.22 N/P), number of nod (17.81), shoot diameter (8.8 mm), root diameter (9.12 mm) and dry weight of root (2.76 g/p) were recorded for first sowing date. Delay in sowing time increased the dry shoot yield significantly as the highest dry shoot yield (3023.1 and 2663.9 kg/ha) was obtained at third and second sowing time. The result of mean comparison showed that the highest root diameter (9.33mm) and dry weight of root (2.56 g/p) were recorded for third density. In addition, the highest plant height (53.03 and 51.09 cm), lateral stem (21.94 and 21.79 N/P), number of nod (17.06 and 16.32) and shoot diameter (7.92 and 7.4 mm) were obtained at third and second densities. Plant density had no significant effect on dry shoot yield. The obtained results showed that morphological characteristics of Satureja hortensis were affected by agronomic treatments and growth performance may be enhanced by proper management.

In order to study the effects of plant density on yield and essential oil yield of four species of thymus, an experiment was conducted at Homand Research Station as a split plot in a randomized complete block design with three replications. Main plots were four species including Thymus daenensis, T. pubescens, T. kotschyanus and T.vulgaris and sub plots were three levels of plant density including 25, 35 and 50 cm row spacing. Measured characteristics included height, number of lateral branches, root length, canopy diameter, root dry weight, fresh and dry yield, essential oil percentage and yeild. Results indicated significant differences in terms of measured traits. Among the measured traits, the effect of density was significant on number of lateral branch, canopy dimeter, fresh yield, and root dry weight. According to the results of interaction effect between species and density, the highest dry yield and essential oil content (%) was obtained at 25 cm row spacing in T.kotschyanus and the lowest was recorded at 50 cm row spacing in T. daenensis. Results showed that the highest essential oil yield was obtained at 25 cm row spacing for T. kotschyanus and T. daenensis.

To study the effect of seed density and plant distance on yield and growth parameters of radish، an experiment was conducted in Research of Station Rice at office Rasht in 2008-2009. This study was set in secondary culture after rice by factorial experiment with randomized complete block design with 3 replications. Treatments consisted of factorial arrangement of three seed density levels (5، 10 and 15 Kg/ha) and plant spacing (20 and 30 cm). Measurements comprising of total production in hectare، weight of one shrub، weight of tuber، weight of foliage، shrub height، leaf number، length of leaf، length and diameter of tuber. Results showed that seed density of 5 Kg in hectare in plant distance of 20 cm with yield of 45. 38 ton in hectare was most performance and recommendable for this region.

Squash is one of medicinal plants that its juice is effective in remedy of cyst illness and increase of body tolerance for disease ingredient. In order to evaluation of distance cultivation effects and ethylene spry on fruit and seed production in squash, an experiment as split plot design on base of randomized complete block design was conducted in the field with 3replications in spring and summer of 2007 and 2008. This research was conducted in agricultural research farm of Islamic Azad University of Shahrekord. The factors were three dose of ethylene (0, 50 and 100 ppm of 2-Chloro-ethylphosphonic acid) and three density of planting (100×50 Cm, 150×50 Cm and 200×50 Cm). Due to prevention of infection between different dose of foliar application of ethylene and convenience of conduction, dose of ethylene was spread in main plots and densities of planting in subplot. Each replication included three main plots (every main plot had three subplots): therefore whole experiment had 27 plots. Evaluated characters in this research were seed yield and yield components including number of fruit per plant, and number of seed per fruit, 100-seed weight. Although the combinations of 100ppm ethylene×100×50cm and 0-ppm ethylene×100×50cm made the most number of fruit in area but the most mean of weight of fruit, mean of weight of fresh seed made by 100ppm ethylene and 200×50cm density. Results showed that 100ppm of ethylene and 200×50Cm density was the best combination, also correlations between weight of fruit, weight of seed, number seed per fruit were positive, and between weight of fruit and number of fruits were negative.

Agrimonia eupatoria L. is a perennial plant that has been distributed in Iran. Its effective components are used to cure some diseases such as hepatitis, control bleeding sedative, and balance especially in women menstrual. The purpose of this investigation was finding the best time and the normal distances in cultivation on seed yield. Three stand density as 30, 40, 50cm (4, 6.2 and 9.2 per m-2) and four planting dates were based on factorial design with three replications, in research institute of forest and rangelands. Results showed 4/m-2 had significant differences on seed yield.

Pumpkin (Cucurbita pepo) is an annual plant that has been introduced to Iran in recent years. Its effective components are used to cure some diseases such as prostat hyperplasia, control of taenia, Arleriosclerosis, regulation of alimentary canal and hormonal balance especially in women and strengthening men sexual appeal in advanced countries. Phosphate is one of the macro-elements affecting root growth and development and seed and fruit yield. On the other hand, regarding to its high and indefinite shoot development, planting density is highly important to get the highest yield. An experiment was conducted to study planting density and phosphate in a faeturial experiment level. Three stand density as 10000, 13000, 16000 per ha and four pure phosphate as 0, 50, 100, 150 kg/ha-1 were based on RBCD with three replications, in Feyz-Abad research station, Qazvin in 2004. Results showed 10000 density had significant effectiveness on node number, shoot length, leaf number, leaf dry weight and lateral shoot number. Phosphate also affected significantly the highest leaf dry weight which was achieved by using 150-kg/ha-1 phosphate. The highest node number has been produced by 100 kg/ha-1 phosphate. 10000 plant/ha caused the highest fruit yield, seed number and seed dry weight. Also, 100 kg/ha-1 phosphate treatment leaded to the most seed number and the highest seed dry weight. Plant population and phosphate fertilizer had no significant difference on the oil content.