جستجوی مقالات مرتبط با کلیدواژه « Growth indices » در نشریات گروه « اکولوژی »

The effects of garlic (Allium sativum) as an effective indicator of hematology and blood serum indices in fingerlings farmed trout (Onchorhynchus mykiss) were studied in the Shahid Motahhari Genetic and Breeding center of coldwater fishes in 2014. 5 diet treatments tested on a diet without garlic as a control, and four diets with different amounts of garlic oil (.05, 1, 1.5, 2) g per kg in three replications. Treatment was designed. 900 fingerling farmed fish with an average weight of 3.41 ± .0.01 mg for 8 weeks and were fed with prepared diets. At the end of the 8th week,  growth and blood serum indices were measured. Specific growth rate (SGR) and percentage of weight increase were affected and in all treatment were improved in comparison to control (P<0.05). The highest specific growth rate was determined in treatment 1 %. The total number of erythrocytes, hemoglobin and hematocrit, mean corpuscular volume of red blood indices in different treatments showed significant changes in fish fed the diets containing high utility plant garlic powder (P<0.05). Cholesterol showed significant difference compared to the control. Glucose showed no significant difference (P>0.05). Blood serum globulins and albumin levels in fish fed diets containing garlic powder were higher than the control group and triglyceride level increased compared to the control diet.

Low yield and total land productivity are the main challenges related to agriculture in developing countries. Crop diversification can help reduce these challenges by introducing legumes in intercropping. Therefore, evaluation of the effects of green bean intercropping with potato (Agria cultivar) on physiological indices, yield and total land output (TLO), were important objectives of this study.

Experiment was conducted at the Agricultural Research Station, Faculty of Agriculture, Bu-Ali Sina University in 2016 growing season. Experiment was laid out as a factorial based on randomized complete block design with three replications. Four planting patterns including sole cropping of potato (M1), cropping green bean between rows of potato (M2), cropping green bean on rows of potato (M3) and cropping  green bean between and on rows of potato (M4) were applied in combination with three levels of nitrogen fertilizer (N0, N80 and N160: 0, 80 and 160 kg N.ha-1, respectively).

The results showed that the highest above ground dry matter accumulation (529 g.m-2) and leaf area index (4.86) were obtained at M1×N160 tretment. The highest crop growth rate (21.72 g.m-2.day-1) was achieved at M2 treatment. Maximum tuber dry matter accumulation (877 g.m-2), tuber growth rate (24.50 g.m-2.day-1), and tuber yield (42.48 t.ha-1) were obtained at M2×N160 treatment. In green bean, the highest dry matter accumulation, LAI, CGR and number of green pods per plant were obtained from M2×N80 treatment. At the canopy level, the highest accumulation of dry matter, LAI, LER and TLO were observed at M2×N80 treatment. Treatment of M2×N80 in comparison with M1×N0 treatment (sole cropping of potato without nitrogen consumption), increased TLO up to 43 percentage.

The cultivation of green beans between rows of potato and the application of 80 kg of nitrogen per hectare, in addition to creating biodiversity and ecosystem stability, causes maximum land productivity.

Water scarcity and frequent droughts are becoming a serious problem particularly in the context of alarming predictions of climate change in the world. Within the arid and semi-arid regions, water availability is a major limitation for crop production. Thus, it is necessary to improve yield and the efficient utilization of limited available water in the irrigated agroecosystems. One possibility to enhance crop yield under water limitation is using soil microorganisms that increase the radiation and water efficiency and uptake capacity. Among these potential soil microorganisms, plant growth-promoting rhizobacteria (PGPR) are the most promising, including all bacteria inhabiting the rhizosphere and the rhizoplane able to simulate plant growth and yield. Therefore, the objective of the present study was to evaluate the effects of the PGPR on the ecophysiological characteristics of soybean under different moisture regimes.

The field experiment was conducted during 2016 at the research farm of Campus of Agriculture and Natural Research, Razi University, Kermanshah, Iran (34°, 19´ N, 47°, 50´ E with 1320 m altitude). A split plot factorial experiment was conducted based on randomized complete block design. Main plots had three irrigation regimes in which irrigation was cut based on the soybean stages (I1: water deficit stress from mid pod development stage to maturity stage; I2: water deficit stress from grain filling development stage to maturity stage; and I3: optimum irrigation in all development stages) and sub-plots were composed of plant growth-promoting rhizobacteria (PGPR) (B1: no bacteria; B2: Bacillus subtilis; and B: Bacillus licheniformis) and soybean cultivar (TMS, M9 and Kosar). The experimental plots were irrigated based on furrow method. I3 treatment were irrigated every 7 days until the end of the growing period while in the I1 and I2 treatments, the plots were irrigated every 7 days until the start of the water deficit stress. In order to inoculate with the PGPR, the soybean seeds were plunged in a 1:10 (v:v) solution of liquid culture and distilled water, respectively for 10 minutes. All seeds including inoculated and no inoculated seeds oven-dried at 30 ℃ for 5 h. Finally, the soybean inoculated seeds by PGPR were inoculated by Rhizobium japonicum before sowing and cultivated immediately at 4 to 5 cm soil depth. The evaluated traits were the leaf area index (LAI), radiation absorption (RA), crop growth rate (CGR), relative growth ratio (RGR), total dry weight (TDW), radiation use efficiency (RUE) and Grain yield (GY).

The results indicated that the water deficit stress reduced the LAI, RA, CGR, RGR, TDW, RUE and GY of soybean. The PGPR application improved all measured traits of soybean in all irrigation regime treatments. The highest LAI (6.7), RA (18.2 MJ.m-2), CGR (20.6 g.m-2.d-1), TDW (1104.7 g.m-2) and RUE (1.165 g.MJ-1) were related to TMS cultivar in the optimum irrigation and B. licheniformis treatment and the lowest them were related to Kosar cultivar under water deficit stress from mid pod development stage to maturity stage and no bacteria treatment. The greatest GY (380.9 g.m-2) was related to TMS cultivar which was observed in the optimum irrigation and B. licheniformis treatment and the lowest GY (134.2 g.m-2) was related to Kosar cultivar which was observed in the water deficit stress from mid pod development stage to maturity stage and no bacteria treatment. In this study, B. licheniformis compared to B. subtilis presented a more effective improvement in soybean LAI, RA, CGR, RGR, TDW, RUE and GY.

It seems that the PGPR could promote the soybean growth and yield via increasing the root system and more uptake of water in the rhizosphere. Nevertheless, as the results showed, the more effects of the PGPR were observed in the I2 treatment compared to other treatments. The PGPR actually could promote the soybean growth and yield in the mid water deficit stress.

Canary seed (Phalaris canariensis L.) from poaceae family is a drought tolerant plant. Canary seed originally is native to Mediterranean region, and can be grown commercially in several parts of the world.
Evaluation of different systems of plant feeding to achieve a high yield and desirable quality is one of the important requirements in agricultural planning . Therefore, gradually replacing chemical fertilizers with biological and organic fertilizers will result in providing nutrient requirements of plants, improvement of physical, chemical and biological conditions of soil and reduction of adverse environmental effects. Therefore, the aim of this research is to study the effect of deficit irrigation and managing the use of chemical and organic fertilizers individually or  combined on yield and yield components of canary seed. To investigate the effects of different levels of irrigation water and integrated management of chemical and organic fertilizers on growth indices, yield and yield components of Canary seed plant, an experiment was conducted as split plot based on a randomized complete block design with three replications at Agricultural Research Station, College of Agriculture, Ferdowsi University of Mashhad, Iran during growing season of 2013-2014.
Main plots considered different irrigation regimes  with three levels (60, 80 and 100 percent of water requirement) and sub-plots considered for fertilizer treatments in six levels (chemical fertilizer, vermicompost fertilizer, manure, chemical fertilizer + vermicompost fertilizer, chemical fertilizer + manure and control). The amounts of treatment of nitrogen chemical fertilizer (200 kg ha-1 of urea source and 150 kg ha-1 of triple super phosphate) were applied in related plots. The amounts of manure fertilizers (30 t ha-1) and vermicompost (6 t ha-1) were determined and applied based on recommended amount of nitrogen. Water requirement of Canary seed was estimated by the OPTIWAT software under general condition of Mashhad
Before final harvest of the grain, 10 bushes were randomly chosen from each plot and traits such as bush height, the number of tillers per bush, the number of prolific tillers in each bush, the number of spikes in each bush, the number of grains in each spike, the grain weight in each spike and bush, 1000 grain weight and harvest index were determined. Then, considering margin from a surface equivalent to 1.4 m2, plants were harvested from the height 3-5 cm and the produced biomass in each plot was recorded. Then, grains were separated from straw and the grain yield was determined in each plot.
Finally, recorded data were analyzed by SAS software ver. 9.1 and mean comparison based on Duncan multiple-range test was conducted by MSTAT-C software in the probability level of 5 percent.  This study results indicated that different levels of water irrigation had significant impact on all studied traits except harvest index. All studied traits except harvest index and 1000-grain weight had been significantly influenced by fertilizer treatments. Interaction of different irrigation regimes and fertilizer treatments had significant effect on the traits including plant height, the number of tillers per plant.  The maximum height of plant was observed in irrigation treatment of 80 percent of water requirement and the maximum number of tillers per plant was observed in irrigation treatment of 100 percent of water requirement. In addition, under the irrigation treatment of 100 percent water requirement and 100 percent water requirement, the maximum number of grains per plant and the maximum biological yield was observed.  The maximum grains per plant and biological yield was observed under animal manure and vermicompost treatments. Animal manure and vermicompost treatments had higher yield than control and chemical fertilizer treatments. In most of the studied traits, irrigation treatment of 100 percent water requirement was not significantly different from 80 percent water requirement irrigation. The authors acknowledge the financial support of the project (grant number 31441, 09 July 2014) Ferdowsi University of Mashhad, Iran.

The current study was carried out in three locations of Fars province included Eghlid, Shiraz and Lar which have a cold, mild and hot-dry climate, respectively. The General Circulation Model HadCM3 under three emission scenarios A2, B1 and A1B in three future periods (2011-30, 2045-65 and 2080-99) was applied. APSIM crop model was also used to simulate the growth and yield of wheat. The Averaged across locations, scenarios and periods in the future, a rising trend was simulated for biomass and grain yield compared with the baseline largely owing to the increasing carbon dioxide concentration (531 ppm). As an example, the highest biomass and grain yield was observed with 2786 and 1051 g.m-2, respectively in Eghlid in 2080-99 under the A2 scenario. Furthermore, considering that the rate of photosynthesis will be increased by increasing the carbon dioxide concentration in the future period, it will have the rising trend compared to the baseline period. According to the result of simulations, the highest increase in LAI was obtained under A2 scenario for 2080-99 in all of locations (23.23%) while the lowest increase in LAI under A2 and B1 observed for 2011-30 (10.83%). The growth and relative growth rates will be increased by increasing of photosynthesis rate and biomass in the all future periods under different emission scenarios. Overall, the results showed that increasing the carbon dioxide concentration in the future resulted in increased NAR. Accordingly, the highest and lowest NAR was simulated for 2080-99 and 2011-30, periods.

In order to investigate growth indices, yield, and nitrogen and phosphorous content in soybean under bio- and chemical fertilizer application, a factorial experiment based on a randomized complete block design with three replications was carried out on the research farm of the Moghan College of Agriculture & Natural Resources during 2015. The first factor, Biosoy Bio-fertilizer containing different strains of Bradyrhizobium japonicum bacteria, included inoculation of seed and non-inoculation; and the second factor, chemical fertilizer, included non-application of fertilizers (0%), 50 kg.ha-1 urea 66 kg.ha-1 diammonium phosphate (33%), 100 kg.ha-1 urea 132 kg.ha-1 diammonium phosphate (66%), and 150 kg.ha-1 urea 200 kg.ha-1 diammonium phosphate (100%). The results showed that the lowest leaf area index (2.17), total dry matter accumulation (374.17 g.m-2), crop growth rate (8.6 g.m-2.d-1), grain yield (3738.3 kg.ha-1), and leaf chlorophyll index (20.83) values were observed from the combined treatment of non-inoculation and non-application of fertilizer. The highest values of leaf area index (5.46), total dry matter accumulation (784.5 g.m-2), crop growth rate (21 g.m-2.d-1), grain yield (7602.8 kg.ha-1), and leaf chlorophyll index (38.16) were recorded from the combined treatment of inoculation by Biosoy and 33% of chemical fertilizer. Inoculation treatments significantly showed higher nitrogen content and nitrogen to phosphorus ratio than non-inoculated ones. All-told, soybean inoculation with Biosoy bio-fertilizer containing Bradyrhizobium japonicum bacteria not only increases soybean growth, development and yield, but also, reduces chemical fertilizers usage, production costs, and environmental risks.

Soil and water salinity is one of the stresses that have limited cucumber production in Iran. The use of cucurbit rootstocks is a valid strategy in increasing cucumber salt tolerance. In order to investigate the effect of the grafting on Shintoza, Cobalt, and Root power rootstocks in salinity condition (40, 60 and 80 mM NaCl) on yield, growth, fruit quality, electrolyte leakage, leaf area, specific leaf area (SLA), SPAD index, leaf relative water content (LRWC), mineral composition, and proline of cucumber plants (cv. Khasib), an factorial experiment was carried out based on completely randomized design (CRD) with three replications. Salinity improved fruit quality in both grafted and ungrafted plants by increasing fruit dry matter and total soluble solids content. Moreover, at the three salt treatments the percentage of yield and biomass reduction was significantly lower in the grafted plants in comparison to ungrafted plants. Grafted cucumber plants exposed to NaCl were capable of maintaining higher fruit yield, plant growth, leaf area, leaf relative water content (LRWC), higher chlorophyll content (SPAD index), a better nutritional status in the root and leaf tissues and higher proline concentration and less electrolytic leakage in comparison with ungrafted ones. These results suggest that rootstocks have a higher capacity for Na exclusion and retention, which resulted in reduced Na transport to the shoot and increased the salt tolerance of cucumber.

To study the effects of different fertilization systems on some growth indices of two maize (Zea mays) varieties، a factorial experiment was conducted based on randomized complete block design with three replications at Agricultural Research Station of University of Kurdistan in 2012. Factors were: different fertilizer levels including (T1) chemical fertilizers (nitrogen and phosphorus as much as 300 and 150 kg. ha-1)، (T2) biological fertilizers (Barvar-2 phosphate biofertilizer (100 g. ha-1) and Nitroxin bio-fertilizer (1 L. ha-1)، (T3) chicken manure (15 ton. ha-1)، (T4) 50% chicken manure + bio-fertilizers، (T5) 50% chemical fertilizer + bio-fertilizers + 50% chicken manure، (T6) control (without fertilizer) and maize varieties including (A1) SC704 cultivar and (A2) DC370 cultivar. Results showed that T5 significantly had the highest total dry weight، leaf area index (LAI)، crop growth rate (CGR) and net assimilation rate (NAR) in SC704. In DC370 the highest total dry weight، LAI، CGR، and NAR obtained from T1. In both cultivars the highest RGR belonged to T5، 21 days after sowing. In different fertilize levels، late maturing SC704 cultivar had more yield than that of DC370. Integrated use of organic، biological and chemical fertilizers caused to produce highest yield compared with application of fertilizers alone.

There are several methods for weed management which one of them is using allelopathic crops. The present study was conducted to investigate the allelopathic effects of rye on seed germination and also seedling growth of sweet corn and some of it’s important weeds including redroot pigweed, lambsquarters, johnsongrass and wild prosomillet in laboratory and greenhouse, based on randomized complete block design (RCBD) with 4 replications. In the laboratory conditions, the effects of different concentrations of the water extract of rye aboveground parts (0, 2.5, 3.75 and 5.0 gr.100 ml-1 water) and in the greenhouse conditions the effects of aboveground parts biomass (0, 4, 8, 16 and 32 gr of rye biomass per 1 kg soil) on germination and seedling growth indices of sweet corn and it’s major weeds were investigated. Rye aqueous extracts showed a negative effect on germination and seedling growth parameters of them. So that, in laboratory conditions, the seed germination of wild proso, lambsquarters, johnsongrass and redroot pigweed were reduced 84.7, 75, 53.3, and 31 %, respectively in the highest concentration of rye extract compare of control. In contrast, there was not a considerable impact on corresponding indices of sweet corn. Seedling emergence of lambsquarters, johnsongrass, redroot pigweed, and wild proso were reduced 79.8, 75, 72.8, and 68.3 % in 32 gr of rye biomass per 1 kg soil, respectively (in greenhouse conditions). Emergence rate of these weeds was reduced by rye biomass. Lambsquarters and redroot pigweed dry weight and length of root and shoot were reduced significantly by all levels of rye biomass. Finally rye residues have an enormous potential to suppress weed species with no harmful influence on sweet corn.