جستجوی مقالات مرتبط با کلیدواژه « spike » در نشریات گروه « کشاورزی »

Wheat is one of the most widely used crops in Iran and the world, which provides about 60 to 70% of human food energy. In sustainable soil management, in addition to soil fertility, it is also important to maintain the balance of its nutrients. In general, reducing the use of chemical fertilizers is necessary to maintain yield and maintain the beneficial properties of the soil, as well as to contribute to the sustainable production of wheat as a strategic product of the country. For this purpose, this study was conducted to investigate the effect of combined use of organic fertilizers and phosphorus on wheat properties and the purpose of reducing the use of chemical fertilizers in order to maintain yield and maintain useful soil properties and ultimately protect the environment.

This experiment was carried out in a field located in Sarbisheh city in 2020 year using Arg wheat cultivar as a split plot and based on a randomized complete block design with three replications. In this study, the application of organic fertilizer at 5 levels in the main plots before planting and the use of phosphorus based on soil test at 4 levels in the sub-plots was done simultaneously with planting with a tiller. In this experiment, plant height, number of leaves, leaf area, plant dry weight, number of tillers, number of spikes per plant, grain yield and protein percentage were measured.

The highest plant height was related to the level of non-application of phosphorus fertilizer and the level of 20 tons per hectare of local compost with a 32.8% increase compared to the control level. It was observed that in the interaction of organic fertilizer and phosphorus fertilizer, the highest leaf area of wheat was related to the level of 20 tons of local compost fertilizer combined with 100% phosphorus fertilizer. It was found that the highest plant dry weight was 20 tons per hectare of local compost, which caused a 50% increase in this trait compared to the control. Also, in the treatment of phosphorus fertilizer, it was found that the highest amount of plant dry weight at the level of 100% of the recommended amount was 4.48 g, which was 34.5% higher than the control level. The interaction of the two factors tested showed that the highest number of tillers was related to the level of 150 kg of phosphorus fertilizer and the level of 20 tons per hectare of local compost, which caused an increase of 1.3 times compared to the control level. The level of 25 tons of manure per hectare increased the number of spikes per plant by 13.7% compared to the control. Also, the level of 20 tons of local compost increased this trait by 15.6% compared to the control. The simple effect of phosphorus fertilizer was observed that the levels of 150 and 100 kg / ha had the highest number of spikes. Phosphorus fertilizer treatment showed that the highest grain yield at the level of 150 kg / ha was 6117 kg / ha, which was an increase of 39.6% compared to the control level.

The results of this study showed that the effect of different fertilizers on most of the studied traits such as plant height, leaf area, leaf and plant dry weight, grain yield and grain protein percentage were significant. The most positive effect on most of the traits due to the simple effect of treatments was local compost treatment and had better results than manure and phosphorus fertilizer.

In order to evaluate the effects of soil and foliar applications of Zargrain organic fertilizer on water-use efficiency, yield and yield components of wheat under drought conditions, two separate factorial experiments (completely randomized design of three replications) were conducted in the greenhouse. Treatments in the first experiment were four levels of foliar application (zero, 2.5, 5 and 7.5 L/1000L) and three moisture levels (field capacity, 75 and 50% of field capacity(FC)) and in the second experiment four levels of soil application (zero, 5, 10 and 20 L/ha) and the mentioned moisture levels. Greenness index, number of claws, number and height of spike, number of seeds per spike, plant height, fresh and dry weights were measured and water-use efficiency was calculated. Both soil and foliar applications methods increased grain yield, plant dry weight, greenness index and water-use efficiency compared to control. Application of 20 L/ha caused a 13% increase in the number of spikes, and the application of 5 to 20 L/ha increased the number of seeds in spike by 22 to 31%, respectively. The number of seeds per spike increased by 7.5 L/1000L foliar application. The highest greenness index (38% increase in 0.75FC treatment) and water-use efficiency (0.55 g/L in 0.5FC condition) was observed with soil application of 20 L/ha fertilizer. Fertilizer application in dry conditions prevented dry-weight loss and soil application was more effective. Application of fertilizer increases the growth/performance of the plant and it can be used to improve the quantity/quality of the yield, especially in arid/semi-arid regions.

Drought stress and consequent lack of available water for plants is one of the main causes of accumulation of reactive oxygen species (ROS) in various organs of plants, which is effective in reducing the yield of cereals such as wheat. The antioxidant system, which contains various enzymes and genes, is responsible for removing and detoxifying plants from ROS. Unfortunately, genes responding to drought stress and their enzymatic activities associated with spike and flag leaf of wheat have received less attention. Therefore, in the present study, photosynthetic parameters, key enzymes of the antioxidant system, and expression analysis of some genes involved in this system under field capacity (FC) and drought stress (DS) conditions in spike and flag leaves of wheat were investigated.

The present study was performed in Azadshahr Research Center, Golestan Province, Iran in 2021. The wheat cultivar used in this study was Qaboos. This cultivar was cultivated under two experimental conditions of field capacity and drought stress in a randomized complete block design with three replications in the field. In the present study, differences in net photosynthesis (PN) rate, transpiration (E), stomatal conductance (gs), chlorophyll (Chl), relative water content (RWC), and the activity of APX, DHAR, MDHAR, and GR enzymes involved in the antioxidant system of flag leaf and spike of wheat were examined under field capacity and drought stress conditions. Transcription levels of APX, DHAR, MDHAR, and GR genes were measured using qRT-PCR under drought stress and field capacity conditions. Flag leaf and spike of Wheat for photosynthetic parameters and enzymatic activities at 0, 5, 10, 15, 20, and 25 and relative gene expression at 0, 1, 3, 5, 10, 15, 20, and 25 days after anthesis (DAA) were harvested. The recorded data were analyzed by analysis of variance and all analyzes were performed by SPSS software. Mean differences were compared using Duncan's multiple range test at 5% probability level.

general, the spike had a better capacity to maintain net photosynthesis, transpiration, stomatal conductance, chlorophyll, and relative water content under drought stress conditions. This superiority reached its peak on the fifth day after anthesis. The enzymatic activity of the antioxidant system was normal under field capacity conditions. However, with the application of drought stress, APX, DHAR, MDHAR, and GR enzymes were affected in both spike and flag leaf of wheat and their activity increased, which indicates more activity of the antioxidant system in spikes and flag leaf of wheat for controls the level of ROS. After more days of grain filling, the activity of enzymes increased, and finally, after the plant entered the senescence stage, the activity of enzymes decreased to some extent. With drought stress, the antioxidant system in spike, especially from the 10th day after anthesis onwards, had a better performance. However, enzymatic activity in flag leaves under drought stress was not significantly different from field capacity conditions. Transcriptional levels of APX, DHAR, MDHAR, and GR genes associated with the antioxidant system increased under drought stress compared to field capacity conditions. It seems that the increase in enzymatic activity simultaneously with the increase in the level of transcription of the genes of the antioxidant system in the spikes and flag leaves of wheat is to counteract the oxidative damage.

the present study, spikes of wheat played a more important role in responding to water deficiency through the antioxidant system than its flag leaf. The results of this study showed a high potential of the spike compared to flag leaf in the face of drought stress and this results in future breeding programs in wheat can play a key role in selecting drought-resistant cultivars with high yield.

Barley (Hordeum vulgare L.) is a widely cultivated cereal crop in many rainfed areas in the Mediterranean region where drought is considered the main yield-limiting factor. In such marginal lands, yield losses are associated with drought conditions resulting from low and inconsistent precipitation during the whole plant growth cycle, either early in the fall or winter (initial drought conditions) or late during spring (terminal drought). Drought stress reduces grain yield of barley by negatively affecting the yield components i.e., number of plants per unit area, number of spikes and grains per plant or unit area and single grain weight, which are determined at different stages of plant development.

In order to investigate the effect of sources limitation on yield and physiological characteristics in barley cultivars and advanced lines in various environmental conditions, an experiment was done in the Agricultural and Natural Resources Research Station of Miandoab in cropping 2016-2017. In this study, 12 varieties and lines of barley were evaluated in five sources limitation treatments including control (without limitation), leaf removal under flag leaf, flag leaf removal, half spike removal and spike coating in normal irrigation and water deficit conditions were evaluated in a randomized complete block design with three replications. In this study spike weight, leaf weight, peduncle weight, internode weight, seed number per spike, total plant weight and single plant yield were measured. Analysis of variance was performed using the SAS9.4 and SPSS programs.

The results of the combined analysis of variance showed that the effect of year on leaf weight and seed yield was significant at the level of 0.01. There was a significant difference between irrigation levels on all studied traits at the level of 0.01, the interaction effect of year in irrigation was also significant on all traits except total plant weight at the level of 0.01 probability. The effect of resource constraint, irrigation on resource constraint, genotype and the interaction of genotype on resource constraint were significant on all studied traits at the level of 0.01 probability. The interaction effect of year on resource constraint on leaf weight, peduncle weight, number of seeds per spike and seed weight was significant at 0.01 probability level. The interaction effect of year on genotype on total plant weight and number of seeds per spike was also significant. The interaction effect of irrigation in genotype was also significant on all traits at 0.01 probability level. Finally, the triple interaction of irrigation in source restriction in genotype on leaf weight and total plant weight was significant at the level of 0.01 and the number of seeds per spike and grain yield at the level of 0.05 probability was significant. Comparison of the mean of genotype with source restriction interaction treatments showed that most of the studied genotypes under normal irrigation conditions showed the lowest grain yield in treatments of flag leaf removal restriction, half spike target and spike cover, while under water deficit stress conditions, the lowest grain yield was recorded in the studied genotypes under the treatments of flag leaf removal and spike cover. Under normal irrigation conditions under control and removal under the flag leaf, genotypes No. 10, 2, 3, 4, 5, 6, 7, 8 and 12 had the highest grain yield and there was no significant difference between them. Under water deficit stress conditions, in the control treatment, all genotypes except genotype No. 11 and in flag removal treatment, all genotypes, except for genotypes No. 2 and 11, had higher yields compared to genotypes. Under normal irrigation conditions and Water-deficit stress in genotype 3, there was no significant difference between control treatment and resource limitation treatments of remove below the flag leaf, flag leaf removal and half spike removal. In this study, the studied advanced lines did not show a significant advantage over the released barley cultivars in terms of grain yield.

It can be concluded that in this study, the studied advanced lines did not show a significant advantage over the released barley cultivars in terms of grain yield.

Since water deficit during plant growth period is one of the main important limiting crop yield. An easy and inexpensive way to reduce the impact of water deficiency is essential. Therefore, the aim of this study was to investigate the effect of seeds osmo-priming on growth, yield and yield components of wheat cultivar Anfarm 4 under field conditions, a factorial experiment based on a completely randomized block design with three replications was conducted at Research Field of Agriculture College, University of Birjand in 2017-2018. The treatments consisted of three levels of irrigation (include 100, 75 and 50% of the plant water requirement) and four levels of seed priming (include 0 (control), -0.3, -0.6 and -0.9 MPa induced by PEG 6000). The results of this experiment showed that irrigation levels had a significant effect on measured traits including plant height, tiller number, spike number, spike length, grain number per spike, 1000 seed weight, biological yield, grain yield (P <0.01). However, no significant effect was observed on harvest index. Seed priming had significant effect on plant height and spike length (P <0.01), number of tillers, number of seeds per spike, biological yield, grain yield (P <0.05). Interaction effects showed a significant effect on all of the traits except harvest index. The results of this study showed that the application of osmotic priming seeds -0.3, -0.6, -0.9 MPa resulted in 2.13, 2.62 and 2.15 times of seed yield at 50% water requirement treatment compared to without seed priming treatment. The results of means comparison showed that osmotic seed priming by polyethylene glycol, resulting in a pressure of -0.6 MPa, under 50% of the water requirement treatment showed the highest grain yield compensate ability. However, in 75% of water requirement treatment, pre-treatment had no significant and positive effect on grain yield, even in -0.9 MPa treatment, had a negative and significant effect on seed yield. Therefore, the application of osmotic seed priming somewhat compensated the damage caused by water shortage on grain yield under stress conditions of 50% of water requirement. While in non-stress conditions, osmotic seed priming had no positive effect on grain yield.

Increasing wheat yield requires an understanding of appropriate management method that are Increasing wheat yield requires an understanding of appropriate management method that are most important sowing date and appropriate cultivars. Evaluation of yield and grain filling rate of bread wheat promising lines to normal and late seeding dates, this experiment was carried out at Gorgan research station during 2015-2017. The experiment was a spilt-plot based on RCBD with three replications. The main factors was two sowing date December 15th (normal seeding date) and January 15th (late seeding date) and the second factor were eight genotype and cultivar of wheat. The results of combined analysis of variance showed that the effects of year, sowing date and interaction effects of year × sowing date were significant on all of traits under study expect of harvest index. Also interaction effects of year × genotype were significant on all of traits under study expect of number of grains per spike and growth degree day to maturity. The suitability of climatic conditions during plant growth in normal seeding (December 15th) caused more tillers fertilized. On the other hand, the warmth and dryness of the air at the later seeding date reduced the number of fertilized tillers. Results showed that with delay in seeding date, mean of growth degree day to physiological maturity decreased. Also results of mean comparison of interaction effects of year × genotype and of year × sowing date showed that the genotype SAUAL/3/MILAN/S87230//BAV92 and Gonbad cultivar had higher length of filling period and rate of effective grain so produced acceptable yields compared to other.

Zinc is one of the most critical nutrient elements limiting the plant growth. To investigate the effects of soil Zn deficiency on some physiological and morphological traits in bread wheat (Triticum aestivum L.), a factorial experiment was conducted based on completely randomized design (CRD) with three replications in greenhouse. Zn-efficient (Bayat and Nik-nejhad) and inefficient (Hirmand and Karaj-1) cultivars were grown in Zn-deficit (0 mg kg-1 soil) and -adequate (5 mg kg-1 soil) soils. The studied traits were 1000 grain weight, number of grains per spike, chlorophyll content, grain, root and leaf Zn concentrations and some morphological traits. The results of variance analysis showed that all traits are significantly (P≤0.01) affected by Zn levels and cultivars, while the interaction effects of Zn level × cultivars were only significant (P≤0.01) for root, shoot and grain Zn concentrations. Mean comparisons of the interaction effects revealed that under soil Zn deficiency, the concentration of root Zn in Zn-efficient cultivars (Nik-nejhad: 59 mg kg-1, Bayat: 44.75 mg kg-1) is significantly (P≤0.01) more than those of Zn-inefficient cultivars (Hirmand: 30.58 mg kg-1, Karaj-1: 32.98 mg kg-1). The grain Zn concentration of Bayat (28.82 mg kg-1) cultivar was also significantly (P≤0.01) more than those of Zn-inefficient cultivars (Hirmand: 24.95 mg kg-1 and karaj-1: 22.85 mg kg-1). The estimation of trait decline percentage under soil Zn deficiency revealed more decrease for shoot dry weight, root and grain Zn concentrations and chlorophyll content in Zn-inefficient cultivars, compared to Zn-efficient ones. In conclusion, the results of the current study demonstrated that Zn-efficient bread wheat cultivars are able to produce more dry matter and accumulate more Zn in grains under soil Zn deficiency conditions.

Medicinal plants are valuable resources that they can play an important role in the health of the community, employment, increasing non-oil exports and preventing the genetic erosion of valuable species. The increasing tendency towards herbal medicine in the treatment of diseases, whether globally or internally, makes it unavoidable the necessity of medicinal plants cultivation in agroecosystems. Isabgol (Plantago ovata Forssk.) is an annual herbal medicinal plant from Plantaginaceae family, which about 25℅ of its seed weight is mucilage. It has originated from arid and semi-arid areas and is used widely in traditional and industrial pharmacology. The seeds of isabgol contain fatty oil, carbohydrates, proteins, mineral element and particularly mucilage which has many medical applications. Low water requirement and short growth period, makes this plant suitable for planting in semi-arid areas such as Khorasan. However, to the best of our knowledge, so far, the adaptability, growth, and yield of this plant have not been fully investigated in this area. Accordingly, the aim of this study was to investigate the effect of plant density and single or combined application of cow manure (CM) and chemical fertilizers (CF) on yield and yield components of the isabgol.

This experiment was arranged as a factorial layout based on a randomized complete block design with three replications at Sarayan Faculty of Agriculture, University of Birjand, Iran during 2017. Fertilization treatments consisted of single (40 t.ha-1 CM and 40 kg.ha-1 CF from the source of NPK) and combined (40 t.ha-1 CM + 20 kg.ha-1 CF and 20 t.ha-1 CM + 40 kg.ha-1 CF) application of organic and chemical fertilizers along with a control (no-fertilizer) which were evaluated at three levels of density (20, 40 and 60 plants. m-2). The measured traits included number of spikes per plant, spike weight, spike length, number of seeds per spike, 1000-seed weight, biological yield, seed yield, harvest index, mucilage percentage, mucilage yield, and seed swelling factor. Data analysis was done using SAS 9.2 and means were compared using FLSD test at a 5% level of probability.

Among all studied traits, the only simple effect of fertilizer application on seed and mucilage yields and the simple effect of plant density on seed yield was significant. Seed yield increased when plant density was enhanced, so that, this index was 459, 504 and 673 kg.ha-1 for planting densities of 20, 40 and 60 plants.m-2, respectively. Fertilizers' application in all levels of density decreased the seed yield. The highest seed yield belonged to non-fertilizer application and 60 plants.m-2 with 806.6 kg.ha-1, and the lowest amount of this index was obtained in 40 t CM + 20 kg CF at density of 40 plant m2 with 272.2 kg.ha-1. In terms of mucilage yield, except the treatment of 20 t CM + 40 kg CF which increased this index by 14%, other fertilizer treatments had no-significant different with control. Considering that the most traits related to yield and yield components of isabgol did not affect significantly fertilizer resources, it can be stated that these plants are suitable for low-input production systems. Therefore, it seems that the application of fertilizer resources in crops that are located prior to isabgol in rotation and availability of remaining nutrients can provide the nutritional requirements of this plant.

However, our findings of the response of isabgol to fertilizer application were different from the results of many previous studies on it, which reported that the use of cow manure in isabgol production, not only does not reduce seed and mucilage yield but also improved them. Probably, the amounts of fertilizers used in the current study have been higher in the plant requirements. Therefore, doing complementary studies with lower levels of fertilizers can be recommended.