جستجوی مقالات مرتبط با کلیدواژه « growth parameters » در نشریات گروه « کشاورزی »

In order to evaluate the effect of foliar application of iron and zinc sulfate on yield and yield components of forage corn (Hybrid 704 Single Cross), an experiment in a randomized complete block design with 3 replications was carried out. The treatments included the control (spraying solution with distilled water), spraying of micronutrients including iron sulfate [FeSO4.7H2O (20% Fe)], zinc sulfate [ZnSO4.7H2O (22% Zn)] and iron sulfate + zinc sulfate with a concentration of 5 in 1000 at the 4-leaves stage, 8-leaves stage and both stages. The results showed that the greatest height (with an average of 190 cm), shoot dry weight (with an average of 1774 g m-2), the number of seeds in a row (with an average of 50), the number of rows (with an average of 17.3) and the number of seeds in a cob (with an average of 867) and the weight of a thousand seeds (average of 312 grams) were resulted from iron and zinc foliar spraying at both stages of 4 and 8 leaves, which increased by 15.3, 31.4, 11.3, 17.3, 28.3 and 20.3% compared to their lowest value (control), respectively. The results of this research indicated that the simultaneous foliar application of iron and zinc had a greater effect on the studied traits compared to the foliar application of each nutrient of iron and zinc alone. Therefore, in order to have forage with rather good characteristics, it is recommended to spray iron and zinc solution simultaneously at both 4 and 8-leaves stages.

In this study, age and growth of Golden Grey Mullet (C. auratus) was investigated during the years 1394-1397 in the coastal waters of Golestan province. This study was the first study on the modeling and implementation of three models for estimating growth parameters of golden mullet (C. auratus) in Iranian waters (Golestan province). During the sampling period, commercial fishing with a size of 27-33 springs was used, and outside of the fishing season, a net with a size of 20 and 30 was used. Biometry of fish was done including fork length with an accuracy of 1 mm, total weight with an accuracy of 1 gram. The length range for golden mullet was 15 to 59.5 cm and the weight range was 52.5 to 1401 grams. The exponential relationship of fork length and total weight (W=0.69L0023) was obtained. Based on the multi-model approach, the best model to show the growth of this fish was the Gumpertz growth model (∆AIC = 1.71, AIC = 46.13), and the logistic model was the best model to depict the growth of this fish according to the AIC information coefficient ( ∆AIC = 1.27, AIC = 50.71). Considering the pressure of legal and illegal fishing on this valuable species, it shows that the population and the amount of fishing in the south-eastern coast of the Caspian Sea are increasing. The results of this study can be used as basic information for catching and exploiting this species in the future.

Length-weight relationship, length abundance, maturity percentage and growth parameters of green tiger prawn caught using trawl nets in Mond and Dayyer-Nakhilo areas located in Bushehr province during the years 2020 (13 August to 15 February) and 2021 (11 April to 9 September). A total of 658 tiger shrimps, including 420 female shrimp and 238 male shrimp were bioassayed. Based on the carapace length of 43.43 mm in the first sexual maturity of the females, 50.71% (213 specimens) were mature and 49.29% (217 specimens) were immature. Also, the relationship between the total length and carapace length of female shrimps was y=0.3679 x - 2.1648 based on linear regression. The relationship between the length and weight of 420 female shrimps and 238 male shrimps caught showed that parameters a, b, and r2 were 0.0099, 3.057, and 0.92 for females and 0.0115, 2.9962, and 0.912 for males, respectively. Based on the Sturges formula, 10 length classes were observed for male and female shrimps caught. The length class of 108-12.3 cm for both males and females had the highest frequency with 110 specimens (46.22%) and 141 specimens (33.57%), respectively. The results of this study showed that the maximum length of male (16 cm) and female (20.5 cm) caught shrimps was less than the infinite length and more than the optimal length. Growth parameters (Clinf, K, t0) for females were -0.057, 2.1 and 72 (mm) and for males -0.075, 1.7 and 62 (mm), respectively. The values of Z, F and M parameters for females were 9.2, 7.4 and 2.16 and for males 7.58, 5.62 and 1.96. The exploitation rate (E) was 0.77 for females and 0.74 for males. These values indicate overexploitation and fishing pressure in the area. Therefore, it is necessary to implement fishing management approaches in these habitats.

Waste tire rubber (WTR) contain significant amounts of zinc (Zn) and they are potential sources of Zn for plants. This study was carried out to investigate the effect of Zn-dissolving Pseudomonas isolates and WTR on growth characteristics and Zn and Fe concentrations of the corn plant. An experiment was conducted in a completely randomized design with factorial arrangement with three replications in a sterile sand -culture in green house condition. The experimental factors include Pseudomonas bacteria at six levels (without inoculation (C) and inoculation with five isolates (B1 to B5)) and Zn treatment from the WTR source at four levels of 0 (C), 100 (T1), 200 (T2) and 300 (T3) mg Zn per kg (equivalent to 0, 9, 18 and 27 g WTR per kg of sand respectively). The results showed that the main effects of the treatments on Photosynthetic performance index, chlorophyll content of leaves, Chlorophyll fluorescence and shoot dry weight were significant. The amount of each of these parameters increased in all bacterial and WTR treatments. The use of WTR (18 g/kg) along with inoculation of isolates increased all measured parameters compared to the control. Root dry weight and zinc concentration in shoots and roots, were affected by the interaction of treatments. The highest amount of plant dry weight was observed in B3+T3 treatment (2.14 fold increase compared to the control (. The concentration of zinc in the plant shoots was the highest in the B4+T3 treatment, which was 20 times higher than the control. The highest concentration of zinc in the root was observed in the presence of isolates B3 and B2 in WTR (18 g/kg) treatment which was 25 and 22 times higher than the control, respectively. The highest concentration of iron in the shoots and roots of the plant was related to the WTR (18 g/kg) treatment with the amount of 28.3 and 30.7 mg kg-1, respectively. The bacterial isolates increased the iron concentration of shoot compared to the control, but no significant difference was observed between the isolates.

Formic acid is simplest member of carboxylic acid family. The effects of formic acid on growth, blood indices, and immune parameters of goldfish fry were examined over 60 days. The goldfish fries (mean weight of 5.10±0.15g) were randomly allocated to four experimental treatments with three replications (25 pieces in each replication) including control treatment (no formic acid) and three treatments which received formic acid (10, 20, 30 gr/ kilogram diet). The results indicated that growth indices (final weight, weight gain, specific growth rate, condition factor, and FCR) were significantly different between the control and experimental treatments. The final weight, weight gain, specific growth rate, and status index in the formic acid treatments had a significant increase compared to the control group. In addition, adding formic acid to goldfish fry food ration improved blood factors and immunity in the fish. The results of study showed that inclusion of folic acid resulted an increase in hematocrit, hemoglobin, number of red blood cells, number of white blood cells, lysozyme, immunoglobin, and total immunoglobin compared to the control group. In general, adding folic acid to the food of goldfish fry improved growth parameters along with blood and immune parameters. According to obtained results, a diet containing 10 g/kg diet proposed to enhance growth performance and immunity of goldfish.

Considering the value of water in agriculture and the limitation of this important and vital resource and the existence of intermittent droughts in the country, saving in consumption and optimal use of available water seems necessary. Today, utilizing saltwater is considered one of the practical and effective approaches to minimize water consumption while achieving acceptable economic performance. Given the scarcity of freshwater sources, the utilization of unconventional water for strawberry cultivation holds significant economic importance. Through the application of innovative technologies, such as magnetic technology, the modification of these water sources can lead to increased quantitative and qualitative yields of agricultural products. Salinity stress, which alters the water and nutrient absorption patterns, directly impacts the plant's yield in terms of both quantity and quality. Strawberry is an important commercial product, and the quantitative and qualitative increase of its yield is emphasized from different aspects. The purpose of this research is to the effect of salinity stress under the influence of a magnetic field on the yield and yield components of the strawberry plant.

The purpose of this research was to investigate the effect of salinity stress under the influence of magnetic fields on the yield and yield components of strawberry plants. The factorial experiment was conducted in the form of a randomized complete block design with three replications in 2021 and 2022 in Neka city. The control treatment included full irrigation in all stages of plant growth with normal water (non-magnetic). The treatments include the type of irrigation water at two levels (Non-Magnetic Water (W1) and Magnetic Water (W2)), and water salinity was at three levels (0.86 dS/m (S1), 20 mM sodium chloride (S2), and 40 mM sodium chloride (S3). The strawberry plant of the Silva cultivar was cultivated in 3 x 4-meter plots with a row spacing of 40 cm and a between the spacing of 40 cm. Magnetization of irrigation water was created by passing water through a permanent magnet with a magnetic field intensity of 0.3 Tesla. The salt used for salinity stress was laboratory sodium chloride. The used irrigation method was drip (tape), and the amount of irrigation water and irrigation cycle was done according to the needs of the plant. Soil moisture monitoring was used to calculate the amount of applied water.

The results of analysis of variance showed that the effect of the irrigation water type and different levels of water salinity on the length, diameter, number of fruits per plant, fruit weight, biomass and plant yield was significant at the 1% probability level. The effect of water salinity on the number of fruits per plant was significant at the 1% probability level and on the fruit length and fruit diameter at the 5% probability level. The interaction effect of irrigation water type and water salinity was also significant at the probability level of 1%. On average, during two years of strawberry cultivation with the application of a magnetic field, the length, diameter, number of fruits per plant, fruit weight, biomass, and plant yield were increased by 9.76, 14.14, 23.05, 27.60, 27.08, and 28.36% respectively. The introduction of 20 and 40 mM sodium chloride resulted in a decrease in the physical characteristics of strawberry fruit and overall yield. The most significant reduction was observed in the number of fruits per plant at the salinity level of 40 mM sodium chloride, exhibiting a 56.69% decrease compared to the control treatment.

The growth of population and expansion of agriculture on one hand and the demand for more harvesting from limited water resources on the other hand, make it necessary to increase water productivity. Lack of water and competition for water resources has caused research to be done in order to reduce water consumption and preserve its resources. Therefore, searching for ways to reduce consumption and preserve water resources is of great importance. One of these methods is using magnetic water. The results of the research showed that the use of magnetic water technology caused a significant increase in the yield and yield components of strawberries compared to the control treatment. In addition, the salinity level of irrigation water had a significant impact on the yield and yield components of strawberries, with the highest yield observed in the treatment without salinity stress when using magnetic water technology. The findings of this study indicate that the application of magnetic water technology can enable the use of low salinity levels and lead to improved strawberry yield.

Dates are one of the most important and strategic fruits in Iran that play a major role in providing employment and livelihood to the people and some of them are exported abroad. Improving the quality of date fruits through foliar application of plant growth regulators and various nutrients can be effective in both improving livelihoods and increasing exports. This study aimed to improve the quality of date fruit Mazafati cultivar by studying some responses of date fruit and also some physiological traits of date tree to foliar application with plant growth regulator salicylic acid and silica element.

This study was conducted in 2019, as a factorial design in a completely randomized design with three replications in a commercial date garden in Iranshahr city of Sistan and Baluchestan province. The studied date trees were Mazafati cultivar, all of which were 14 years old and were located at a distance of 7 × 7 meters from each other. Salicylic acid and silica included three levels of 0, 200 and 400 mg L-1 and 0, 100 and 200 mg L-1, respectively. After applying the treatments, fresh samples of date leaves and fruits were transferred to the Plant Physiology Laboratory of Kerman University of Graduate Studies and Advanced Technologies and some morphological and physiological traits of date tree leaves were measured. In addition, some traits related to the quality of date fruit were measured.

The results of data analysis showed that the interaction effect of salicylic acid and silica was significant for all studied traits and significantly improved the quality of date fruit. Date fruit characteristics such as cluster weight and fruit weight are affected by the interaction of 200 mg/L salicylic acid and 200 mg/L silica levels by 34 and 36%, respectively, and fruit length, kernel weight, and kernel size are affected by 200 mg/L silica. They increased by 16, 5 and 14 percent respectively. In addition, the physiological traits of photosynthetic pigments, free amino acids, reducing sugars, soluble proteins, and enzymatic antioxidants were significantly increased by the interaction of salicylic acid and silica. The interaction effect of 400 mg /L salicylic acid and 100 mg /L silica had the greatest effect on the quality of date fruit and physiological traits of date palm and can be used to improve the quality of date fruit.

Foliar application of plant growth regulator salicylic acid and silica significantly improved the quality of date fruit, part of this effect was direct and the other part was indirect through the effect on the physiological traits of tree leaves. Increasing photosynthetic pigments, free amino acids and reducing sugars in palm leaves under the influence of salicylic acid and silica, leads to more photosynthesis and increased leaf nutrients. This will lead to better nutrition of date fruits and ultimately increase their size. The results showed that the interaction effect of 400 mg L-1 salicylic acid and 100 mg L-1 silica had the greatest effect on fruit quality and physiological traits of palm leaves.

Lactobacillus casei probiotic is one of the probiotics used in aquaculture industry. The aim of this study was to evaluate the effect of Lactobacillus casei probiotic on the growth performance, blood parameters, and intestinal microbial flora in goldfish (Carassius auratus) for 60 days. In this study, 180 fish with an average weight of 10.11± 0.16 g were randomly distributed into two treatments with three replicates (n= 30) including commercial diet (control treatment) and diet containing L. casei probiotics at 107 CFU / g (experimental treatment).The results showed that the final weight, weight gain, specific growth rate (SGR) and condition factor (CF) in the treatment containing L. casei had a significant increase compared to the control group (P <0.05). The results also showed that the inclusion of L. casei probiotic to the goldfish diet resulted in increase the number of white blood cells compared to the control group (P<0.05). Moreover, a significant increase in total number and intestinal lactic acid bacteria in the treatment containing probiotic Lactobacillus was observed compared to the control group (P<0.05). Therefore, addition of L. casei probiotic enhanced growth performance and intestinal lactic acid bacteria in goldfish (C. auratus).

The aim of this study was investigation of some reproductive traits of Aphaniops hormuzensis in the Mehran River. Of 664 recorded individuals, 290 specimens were male (43.67%), and 374 specimens were female (56.32%). The sex ratio (females/males) was 1.28:1 (P<0.05). The smallest and biggest size of fish were 19.8 mm and 45.7 mm, respectively which belonged to female. Both sexes showed negative allometric growth. Fecundity ranged from 4 (total length 22 mm, weight 0.36 g) to 73 (total length 45.7 mm, weight 2.3 g) eggs per individual. The highest value of GSI obtained in April (14.32±5.18). This fish had actively breeding during March to October with a remarkable peak in spring. Asymptotic length (L∞), growth rate (k) and t0 were 45.69 mm, 0.73 per year, and -1.19 for males, respectively and 47.05 mm, 0.72 per year and -1.2 for females. The obtained results of this study can be used for determining the strategies for further conservation and management policies of this species with the aim of preserving the biodiversity.

Fusarium wilt on cucumber caused by Fusarium oxysporum f. sp. radicis-cucumerinum is an important and common disease of cucumber in Iran. In this study, differences of pathogenicity between several isolates and their impact were assessed on the plant growth parameters. The pathogenicity of 50 isolates collected from cucumber plants with wilting and yellowing symptoms from different geographic areas of Iran, were examined on cucumber, Negin cultivar. The inoculated and control plants were placed at 25°C for 14 days. Disease severity and the weight of root and crown were measured 10 days post-inoculation. Studied factors showed significant difference at 1% level among isolates of F. oxysporum f. sp. radicis-cucumerinum. The maximum percentage of disease was observed in plants treated by F-111-2, F-133-2 and H8; while the highest disease severity induced in plants treated by F-111-2, F-160-12 and F-111-5. F-111-5, F-160-12 and F-121-4 incited the most decrease in root weight. The crown weight decrease in the presence of F-160-12, F-121-4 and F-111-10 isolates of Fusarium oxysporum f. sp. radicis-cucumerinum correspondingly. Totally, due to the results, it could be concluded that f-160-12 can be considered as the most severe pathogenic isolate.

The long nose sturgeon (Acipenser stellatus, Pallas, 1771) is an anadromous sturgeon species, yet little is known with regard to salt bath effect on bacterial adhesion on superficial organs of this species and its growth. This study was conducted to determine the optimal salt bath concentration on growth parameters and total bacteria count on juvenile stellate sturgeon gill and skin. A total of 200 fishes with mean initial weight 494.5 ± 2.17 g and length 62.63 ± 0.18 cm (mean ± SD) were randomly distributed into 12 concrete pools in groups of 25. Fishes exposed to acute salinity of 0, 5, 10, and 15ppt for 30 minutes. Salt bath is used 5 times for 60 days (1, 15, 30, 45 and 60). At the end of 60th day, growth indices including body weight, SGR, BWI, ADG, PER and FE revealed a significant increase at 5ppt salinity (P< 0.05) and fishes exposed to 15ppt exhibited the poorest growth. No statistical significant difference was observed between control and other treatments in total protein and albumin, also in total bacteria count in gill and skin of fishes (P>0.05) but higher levels of total protein and albumin and lower level of total bacteria observed in 5ppt treatment. The results of this study indicate that high acute salinity may compromise the growth of juvenile long nose sturgeon and suggest that, in commercial operations, salinity should be 5ppt.

Aquaponic is considered a sustainable semi-closed system for food production that combines aquaculture and hydroponics. The aims of this study were to evaluate the influence of aquaponic on the growth and feed performance, digestive enzyme activity and blood parameters of Common carp juveniles for 60 days. This experiment consisted of three groups (three replications per group) which included; cultivation of common carp without plants (T0), use of aquaponic system for culturing common carp with lettuce (TL) and cucumber (TC). A total of 225 carp (initial body weight: 11.59 ± 0.41g) were randomly distributed in nine 60-L tanks. Results showed that aquaponic system in TL and TC groups could increase the weight gain (WG) and specific growth rate (SGR) and reduce the feed conversion ratio (FCR) of common carp. Total protease, amylase, and lipase activities were also significantly higher in TL and TC groups than control group, respectively. After 60 days, serum lysozyme activity and total immunoglobulin were significantly higher and serum cortisol and glucose levels were lower in aquaponic groups than the control group. The highest serum catalase and superoxide dismutase were observed in TL and TC group. The best effect on growth, digestive enzymes, and immune response were shown in TL and TC groups (Aquaponic system) compared to control.

In the present study, the effect of different carbon sources on water quality and growth performance of common carp (Cyprinus carpio) fingerlings by adding synbiotic into biofloc system (BFT) were investigated for 45 days. Three experimental treatments (B, C and D) containing corn, wheat and barley flours together with a control group (A) were prepared. The used synbiotic was a mixture of Bacillus circulans and B. lichiformis along with a Celmanax liquid commercial prebiotic at a final concentration of 1.5×108 CFU/ml to each treatment. Fish fingerling (15.98±1.93 g) was distributed randomly into 12 tanks (4 treatments × 3 riplicated) with 30 liters of capacity. At the end of the experiment, the nitrate, total hardness and total suspended solidsin in all treatments significantly increased compared with the control (P<0.05). While, the dissolved oxygen in all treatments was lower than the control (P<0.05). NO3 was measured higher than the control only in corn and barley treatments (P<0.05). The highest final weight (40.31±11.20 g), SGR (1.59±0.27%), TGC (0.98±0.09%), condition factor (2.21±0.17), FCE (106.09±29.47%), PER (4.71±1.31), PEL (18.22±5.04) and PEE (0.13±0.04) were recorded in corn flour treatment. However, the lowest feed conversion ratio (1.01±0.25) and relative feed intake (11.94±3.79%) were observed in corn flour treatment (P<0.05). The highest excretion rates of ammonia (1011.45±14.27 mg.kg-1BW.day-1), urea (25.30±3.57 mg.kg-1BW.day-1) and energy wast by excretion rates of ammonia (25.36±3.50 mg.kg-1BW.day-1) and urea (6.21±0.78 mg.kg-1BW.day-1) were recorded in barley flour (P<0.05). In conclusion, the results demonstrat that the use of corn flour with synbiotic in the BFT system, compared to other carbon sources was more effective to improve the water quality and promoting of growth preformance of common carp fingerlings.