جستجوی مقالات مرتبط با کلیدواژه « grain yield » در نشریات گروه « اکولوژی »

This study was performed to investigate the effect of nitrogen fertilizer levels and pre-planting of cover crops on some vegetative traits and yield of rice plants.

This was conducted over 2017-2018 and 2018-2019, at the research farm of Sari University of Agricultural Sciences and Natural Resources. The experimental design employed a three-replicated split-plot arrangement within a randomized complete block design. The main plots involved five nitrogen consumption levels (0, 120, 240, 320, and 400 kg ha-1). The sub-plots included four types of pre-planted cover crops (no cover crop, canola, bersim clover, and rye).

Based on the findings, employing berseem clover as a cover crop in pre-sowing resulted in a significantly more favorable rice yield than others. Nitrogen fertilizer at rates of 320- 400 kg ha-1 led to enhanced vegetative traits, yield, and various yield components, including leaf area index and tiller number, ultimately resulting in increased overall yield. Results revealed that planting bersim clover cover crop before planting rice, along with 320 kg ha-1 of urea fertilizer, leads to 41.5% higher yield compared to no fertilizer).).

Bersim clover stood out among the pre-planting cover crops, significantly enhancing many rice traits. Additionally, no significant difference was observed between urea fertilizer levels of 320 and 400 kg ha-1 in several measured traits. Thus, the integrated treatment of bersim clover cover crop and 320 kg ha-1 of urea fertilizer is recommended before planting rice.

The purpose of the experiment was to determine and identify new cultivars to replace them with old cultivars in two climates, cold-temperate (Alborz province) and humid warm-temperate (Golestan province).

The experiment was carried out during two years (2017-18 and 2018-19) in Alborz and Golestan provinces by using 14 spring and 10 winter rapeseed varieties in a randomized complete block design with three replications.

In Gorgan region, cultivars DK 7170, Trapper, Hyola 50, Hyola 401 and Hyola 420 had more grain yield potential with lower ADD for the beginning of flowering and more leaf area index and SPAD index compared to RGS003 cultivar (control). In the Karaj region, the new and intermediate-maturing winter genotypes (Nafis and HL3721 line) had the higher seed yield due to less ADD for the beginning of flowering and the growth period duration, more silique per plant, and higher seeds per silique, thousand seed weight, leaf area index and SPAD index (significant difference) compared to okapi variety (control).

Trapper, Hyola 50 and Delgan cultivars with seed yield ranged from 2500 to 3000 kg.ha-1for planting in Gorgan region and Nafis cultivar with seed yield ranged from 3200 to 3300 kg.ha-1 for planting in Karaj region were recognized as suitable and high potential and good substitutes for the old RGS003 and Okapi cultivars, respectively.

In order to study the production potential and competitive power of barley and vetch plants in the mixed cropping pattern under the influence of different planting patterns and the use of nitrogen fertilizer, an experiment was carried out in the 2017-2018 crop year in two research stations of Sisab and Shirvan in North Khorasan province. The type of experimental design was a split plot based on a randomized complete block design, the main factor including nitrogen fertilizer at three levels (0, 50 and 100 kg/ha)and the sub-factor of different cultivation patterns at five levels(barley monoculture, vetch monoculture, Incremental ratios:15, 30, and 45 increased the density of vetch to barley)and the cultivation was mixed and additive. The results showed that the highest amount of barley ash was obtained in the 45:100 mixed crop treatment and in the 100 kg nitrogen fertilizer treatment, while the lowest amount of this trait was in the 100:15 mixed crop treatments and the pure barley crop, which was in the no nitrogen treatment. Was obtained. The highest yield of barley seeds was obtained in the pure cultivation of barley and in the nitrogen treatment of 100 kg/ha (1675 kg/ha), that related to Sisab region and the lowest yield was obtained in the mixed crop of 100:45 and the nitrogen fertilizer treatment (790 kg/ha) that related to Shirvan region. The index of land equality ratio in mixed cropping treatment of 100:45 and nitrogen fertilizer 50 kg had the highest value (LER=1.158) which was obtained in Shirvan region.

The objectives of this research were to evaluate the relationships between traits of different sesame genotypes and determine the most important traits affecting on the grain yield under control and humic acid application. This experiment was carried out under control and humic acid application (250 gr humic acid per 1000 liter water). Each experiment was conducted using randomized complete block design with three replications in Abarkouh. Sesame genotypes were including Varamin 2822, Halil, Dashtestan 2, Dashtestan 5, Darab 1, Darab 14, Yazd, Jiroft 13 and Safi Abad. Grain yield under both conditions had significant positive correlation with biological yield, harvest index, 1000 seed weight, oil percentage, protein percentage, number of branches and number of seeds per capsule. By stepwise regression, number of branches and 1000 seed weight under control condition and number of seeds per capsule under humic acid application were entered to the stepwise regression model. The result of path analysis showed that number of branches under control condition and number of seeds per capsule under humic acid application had the most positive direct effect on grain yield. Studied genotypes using cluster analysis classified into three groups. Number of branches under control condition and number of seeds per capsule under humic acid application was one of the most important traits in sesame genotypes. According to cluster analysis, Dashtestan 2 and Darab 14 were better genotypes and so these genotypes could be used for achieving to high yield in sesame..

 One of the most important issues in improving the growth and increasing the yield of oil plants is proper nutrition and providing the nutrients needed by the plant during the growing season. Today, the use of biofertilizers in agriculture is considered as an effective way to reduce the consumption of chemical inputs to increase the quantitative and qualitative yield of plants, using beneficial soil microorganisms. Among these organisms, phosphate-solubilizing bacteria can be mentioned, which can increase the phosphorus uptake efficiency of plants. According to reports, humic acid is a stimulant of plant growth mainly by changing the root structure and growth dynamics, increases the root size, branching and its density.

A field experiment was conducted at the agricultural research station, Bu-Ali Sina University in 2020 growing season. The employed soybean cultivar was Habit. This factorial experiment was performed based on a randomized complete blocks design with three replications. Experiment factors were two levels of phosphorus fertilizer including application and non-application, biophosphate including inoculated and non-inoculated and foliar application of humic acid including 0, 2 and 4 g/l (during two stages of 15 and 30 days after emergence at the rate of 250 liters per hectare). In the present study, the interaction effect of humic acid and phosphate solubilizing biofertilizer was evaluated on phosphorus agronomic efficiency, water use efficiency, yield, yield components and quality characteristics of soybean. In this study, after checking the residual normality of the data, SAS software (Ver. 9.1) was used to analyze the variance of the data. Also to compare the means, Duncan's multiple range test at the level of 5% probability was used.

    The results showed that with phosphorus fertilizer application, simultaneous use of biophosphate and humic acid increased plant height (19.2%), biological yield (28.8%) and number of pods per plant (20.4%) compared to the lack of biophosphate and humic acid conditions. For the treatment level of non-use of phosphorus fertilizer and use of biophosphate, foliar application of 4 g/l of humic acid compared to 2 g/l increased the biological yield of soybean by 13.9%. 1000-grain weight of soybeans in phosphorus fertilizer application conditions did not show a significant difference between humic acid levels, but in non-phosphorus fertilizer conditions, foliar application of 4 g/l of humic acid caused a significant increase in 1000-grain weight compared to non-humic acid treatment. It seems that the application of humic acid has strengthened the relationship of the plant with phosphate solubilizing bacteria. Also the number of grains per pod of soybean increased by 14.6% with the use of biophosphate and 16.8% with the foliar application of 4 g/l of humic acid compared to the conditions of no-application of any of them. Applicatin of 4 g/l of humic acid and application of biophosphate increased grain yield by 27.3% and 26.4%, respectively. The highest percentage of seed oil (23.21) was obtained in the absence of phosphorus fertilizer and simultaneous application of 4 g/l of humic acid and biophosphate, while the highest percentage of grain protein (51.3) was obtained in the presence of phosphorus fertilizer, 4 g/l of humic acid and no biophosphate. In the absence of available phosphorus in the soil, the application of biophosphate takes precedence over foliar application of humic acid. This is evident as, without biophosphate application, there was no significant difference in the percentage of seed oil across various levels of humic acid. When biophosphate and humic acid were used in combination, compared to the sole use of biophosphate, the individual application of 4 g/l and 2 g/l of humic acid increased phosphorus agronomic efficiency by 21.1%, 35.7%, and 48.3%, respectively. The results indicate that the combined use of biophosphate and foliar application of 4 g/l of humic acid, in comparison to their absence, improved the water use efficiency of soybean by 25% and 26%, respectively.

Therefore, simultaneous application of 4 g/l of humic acid and biophosphate can improve growth, yield and increase soybean phosphorus agronomic efficiency and water use efficiency. However, to achieve a higher percentage of seed oil, the use of 4 g/l of humic acid alone is recommended.

this research was carried out in order to recognition and evaluate the characteristics related to growth and yield as well as the adaptation of sunflower especially in relation to dehydration conditions.

This research carried as a split plots in a randomized complete block design with three replication and with two factor: irrigation as the main factor and cultivar as sub - factor were performed in the experimental farm of Safiabad Research Center.

Evaluation of means showed, severe irrigation low stress caused a decrease of 19.03, 26.97, 24.34 and 45.08 % respectively in stem height, stem diameter, head diameter and biological yield. Yield and grain yield components of sunflower cultivars also evalouation under the influence of low irrigation stress and the results show a decrease of 45.69, 49.94 and 50 %, respectively in number of grains/head, grain weight/head and grain yield. On the other hand, the percentage of grain oil decreased enough 26.67% under the influence of low irrigation. Oscar cultivar in control treatment with average grain yield of 5.34 t/ha and Shakira cultivar in severe irrigation low stress conditions with average grain yield 2.67 t/ha, respectively produced the highest and lowest grain yield/ha.

despite relative resistance sunflower dehydration stress, maximum grain yield is produced under normal irrigation conditions. Finally, Felix and Labad cultivars according to high grain yield and maintaining yield in conditions of low irrigation stress they are recommended as high yield and compatible cultivars in Dezful region and similar regions.

The present study was conducted to compare the genetic diversity of 158 foreign and iranian safflower genotypes with six Iranian safflower cultivars.

The experiment was carried out in the Augment design with three replications during the 2017-17 at Zahak Agricultural and Natural Resources Research Station in Zabol county.

In principal components analysis (PCA), the first component was named grain yield and dry matter and the second component was named phenology. Based on the results of biplot, genotypes were classified into four groups. The first group includes late matutity and tall genotypes, the second group includes genotypes with high grain yield and harvest index (HI), the third group includes late matutity genotypes with low grain yield and the fourth group includes early matutity genotypes with lowest grain yield and HI. Genotype No. 100 with unknown origin (6044 kg.ha-1) had the highest grain yield and genotypes No. 153 (Mexico), 169 (Mexico), 134 (North Korea), 122 (Poland), 124 (unknown), 130 (unknown) and 131 (North Korea) had high grain yield. The orthogonal comparison of 20 Iranian genotypes versus 138 foreign genotypes showed that no difference was observed for plant height, but in terms of grain yield, biomass and harvest index, foreign genotypes were significantly higher than Iranian genotypes.

Genetic diversity by different statistical analyzes was well able to differentiate safflower genotypes and can be used from grouping obtained from statistical methods for select appropriate parents genotypes in safflower breeding programs.

One of the important ways to reduce the effects of drought stress is the use of biofertilizers in triticale plant. The aim of this study was to investigate the effect of vermicompost and mycorrhiza on grain filling components and dry matter remobilization of triticale under rainfed and supplementary irrigation conditions.

Methods & Materials: 

An experiment as factorial was conducted based on randomized complete block design with three replications at the research farm of University of Mohaghegh Ardabil during 2022. Average rainfall was about 300 mm that most rainfall concentrated between winter and spring. The experimental factors were included irrigation levels (no irrigation as rainfed, supplementary irrigation at heading and booting stages) and application of biofertilizers (no application biofertilizers, application of vermicompost, Mycorrhiza, both application vermicompost and Mycorrhiza).

The results showed that the application of mycorrhizae and vermicompost and supplementary irrigation at booting stage increased root weight and volume (53.6 and 45.49%, respectively), maximum of grain weight, grain filling rate and period (54.04, 19.84 and 21.99% respectively), grain yield (48.66%), current photosynthesis (109.68%) and contribution of its in grain yield (41.14%) and decreased of dry matter remobilization from shoot and stem and contribution of them in grain yield (32.72, 33.55, 97.14 and 98.49% respectively) in comparison with no application of biofertilizers under rainfed condition.

It seems that the application of mycorrhizae and vermicompost and supplementary irrigation at booting stage can increase the yield of triticale in rainfed condition due to improving photosynthesis and grain filling components.

Evaluation, identification, and conservation of native ecotypes of medicinal plants as human heritage are essential. Therefore, collecting and evaluating native ecotypes, as well as introducing adaptive ecotypes, are important for farmers. In order to evaluate the agricultural characteristics of 49 ecotypes of the dragon's head collected from different regions of the country, a randomized complete block design with three replications was applied at the research farm of the Faculty of Agriculture at Tabriz University. The tallest plant was associated with the ecotype number 6 (Kolvanagh 5), with an average of 41.13 cm. The ecotype number 23 exhibited the highest number of leaves on the main stem, with an average of 30.14 leaves. The highest chlorophyll index was associated with ecotype number 49 (Nazirlo and Darwish Bakal villages), averaging 36.04. The highest leaf area index was associated with ecotype No. 20, averaging 2.89 cm2. The highest seed yield of a single plant was associated with ecotype number 25 (the local population of Taze Kand 1 Haris village), averaging 1.05 g. The findings indicate that ecotypes No. 7 (Kolvanagh 6) and 14 (Tabriz 3), which exhibited the highest biological performance, could be used for fodder production.

The experiment was performed to investigate the effect of different sources of nitrogen fertilizer on yield and yield components of linseed Norman variety.

The experiment was conducted in the form of a randomized complete block design with 13 treatments in 3 replications in April 2012 in farm of Yasouj university. Experimental treatments during : T1-control (without fertilizer application), T2- application of 90 kg.ha-1 urea, T3- application of 10 tons.ha-1 of vermicompost, T4- application of 5 tons.ha-1 of vermicompost, T5- application of Barvar1 biofertilizer (containing sAzotobacter (100 g.ha-1) T6- application of biofertilizer nanoparticles of zinc, copper, iron and nitrogen-fixing bacteria (1 kg.ha-1), T7- application of 45 kg.ha-1 urea + 5 tons.ha-1 of vermicompost, T8- application of 45 kg.ha-1 of urea + Barvar1 biofertilizer, T9- application of 45 kg.ha-1 of urea + nano biofertilizer, T10- application of 5 tons.ha-1 of vermicompost + nano biofertilizer, T11- application of 5 tons.ha-1 of vermicompost + Barvar1 biofertilizer, T12- application of 45 kg.ha-1 of urea + 5 tons.ha-1 of vermicompost + biofertilizer Barvar1, T13- application of 45 kg.ha-1 of urea + 5 Tons.ha-1 of vermicompost + nano biofertilizer.

The results showed that different fertilizer treatments caused a significant increase in morphological traits, yield and yield components, biological yield, oil yield and protein percentage of linseed compared to the control.

Due to the water limitation in Iran and the widespread use of maize in human and animal feeding, this research was carried out to evaluate the effects of different salicylic acid levels on some morphological traits and grain yield of this crop under drought stress during reproductive stages. A field experiment was conducted as a split-plot based on a randomized complete block design with three replications in 2020 to investigate the effect of salicylic acid (SA) levels (0, 1, 2 and 3 mM) on morphological traits, grain yield and yield components of maize under normal irrigation and irrigation disruptions at reproductive stages. Irrigation and SA levels were assigned to the main and sub plots, respectively. The results revealed that irrigation disruptions from initial flowering up to maturity caused a significant decrease in the mean plant height, ear length, grains per ear and plant, 1000-grain weight, grain yield, plant biomass and harvest index. Foliar spray of salicylic acid, especially with 3 mM concentration increased most of these traits as well as 1000-grain weight, leading to an improvement in grain yield per unit area. The 1000-grain weight, harvest index, plant biomass, ear length, grains per plant and ear had the highest positive correlation with grain yield of maize. Water supply during grain filling stage is necessary to obtain a higher yield in maize. Foliar application of 3 mM salicylic acid was the superior treatment for increasing maize yield under normal and limited irrigation conditions.

The aim of this research was improvement of dryland farms production by selecting of cultivars and suitable seed density of dryland barley cultivars under entezar conditions of cold regions.

An experiment was carried out during 2019-2020 in North Khorasan province in the form of split plots in a completely randomized block design with three replications. Dryland spring and winter barley cultivars were evaluated as main plot and five densities of 150, 200, 250, 300 and 350 seeds per square meter were evaluated as sub-plots.

Spring cultivars showed better matching for entezar conditions. The results showed that in the first year, despite the superiority of grain yield of spring cultivars, this difference was not significant, but in the second year, spring Mahoor cultivar with 2393 kg / ha showed the highest and Artan winter barley with 1810 kg / ha showed the lowest grain yield, which indicated superiority of 32.2% in grain yield of Mahoor compared to Artan. Higher seed densities (250, 300 and 350 seeds/m2) showed maximum grain yield and were significantly superior to lower seed densities (150 and 200 seeds/m2).

According to the results, for entezar cultivation in cold area, spring barley cultivars such as Khorram, Behdan and Mahoor are suitable however, facultative Nader cultivar also had acceptable grain yield in these conditions and can replace spring cultivars if necessary to escape severe cold damage. Desirable seed density of barley cultivars for sowing in dryland entezar conditions will be 250-350 seeds/m2.

This experiment was performed to investigate the effects of drought stress and nitrogen fertilizer on yield, yield components and some physiological characteristics of four wheat cultivars.

The experiment was carried out in double split plots in a randomized complete block design with three replications in the research farm of Isfahan University of Technology. Experimental factors include two irrigation regimes (irrigation 100 and 50% of plant water requirement for normal and drought stress, respectively), two levels of nitrogen fertilizer (soil content and use of 150 kg urea per hectare) and wheat cultivars (Pishtaz, Bahar, Sepahan and Star).

Drought stress decreased grain and biomass yield by decreasing the content of chlorophyll a, b, carotenoids and leaf relative water content as well as increasing the amount of ion leakage. The use of nitrogen under normal irrigation conditions increased grain and biomass yield, but under drought stress conditions increased biomass and decreased grain yield. Pishtaz cultivar had the highest grain yield (4710 kg / ha), and Star cultivar had the highest amount of biomass (11639 kg / ha). Also, the highest grain and biomass yield were observed in normal irrigation and nitrogen treatment.

The use of nitrogen to increase yield depends on the amount of water available to the plant, and under drought stress conditions, the use of nitrogen is not only a good way to reduce the impact of water stress and yield, but also intensify stress and reduce grain yield of studied wheat cultivars.

The aim of this research was to evaluate the chlorophyll, grain yield and yield components of pinto beans in different intercropping pattern with madder during three years of growth of madder.

The research was carried out during 2018-2020 in the research farm of Jihad Keshavarzi in Varzeghan city. The experimental design was randomized complete block in three replications. Treatments were six cropping patterns included bean and madder pure cropping,4 intercropping pattern of madder and bean as 1:2,2:2,2:4 and3:4, respectively.

Analysis of variance showed that the year and pattern of intercropping had a significant effect on the grain yield and yield components of bean. The results of comparing the means showed that the highest height of the bean plant (63.6 cm) leaf chlorophyll index (42) and grain yield (2806.7 kg/ha) were observed in first growing season. The highest height of bean plant (63.7 cm) , leaf chlorophyll index (43.7) and grain yield (2918.6 kg/ha) were obtained in the two row cultivation pattern of maddder with two rows of beans, which had significant difference with other patterns. The harvest index was not significantly different between the cropping patterns.

The mixed cropping of 2:2 had the highest grain yield in the first growing year,of madder which can be recommended to farmers in sustainable production systems.

According to the high medicinal value of fennel (Foeniclum vuglare Mill), due to its slow growth rate and weak canopy structure, application of straw mulch and herbicide can be considered in the integrated weed management. Therefore, the purpose of this study was to evaluate the different levels of wheat straw mulch and application of linuron herbicide on weed control, yield and yield components of fennel under weather conditions of Khuzestan.

An experiment was conducted as split plot based on randomized complete block design (RCBD) with three replications at Agricultural Sciences and Natural Resources University of Khuzestan in 2019-2020 years. The main plot includes different dosage of linuron herbicide with formulation SC 45% (0, 1.5, 3 and 4.5 L/ha, equivalent to 0, 675, 1350 and 2025 g a.i/ha respectively) and the second factor was different levels of wheat straw mulch (0, 3, 6, 9 and 12 t/ha).

The results indicated that application different dosage of herbicide and different levels of mulch had a significant effect on total biomass of weeds compared to the non-application of mulch and herbicides. The highest grain yield was related to the application of herbicide application 3 L/ha with application mulch 9 ton/ha 80g/ m2). In the absence of mulch and herbicide, the lowest grain yield of fennel (18 g/m2) was obtained.

Due to the poor control efficiency of Linuron herbicide alone, the combination of herbicide with mulch can provide better weed control