Plant Production Technology
Year:2015 | Volume:14 | Issue:2|Papers Count:14

Investigation of weed seed production and its characteristics in competition with crop is important in prediction and long-term management of weeds. Thus, in this study were conducted two field and laboratory experiments. Factors of field experiment were included of four wheat cultivars (Sayson, Alvand, Chamran and Sepahan) and feral rye densities at four levels (20, 40, 60 and 80 plants m-2) and was carried out based on a randomized complete block design with three replications. In laboratory project for study of related traits to weed germination, 25 feral rye seed from each of interference plots of field experiment was harvested and was considered as an experimental unit. In the farm were measured seed yield, number of fertile spike, number of seed per spike, number of seed per unit area and 1000-grain weight of feral rye. In the laboratory condition, cumulative germination percentage, mean germination time, plumule length, radicle length, plumule and radicle dry weight of feral rye were studied. Results showed that inhabitation effects of Alvand and Sepahan cultivars on number of fertile spike, seed yield and seed number of feral rye were more than Chamran and Sayson cv. Also, feral rye seeds obtained of interference with Alvand and Sepahan cv. had lower percentage and rate of cumulative germination than other two cultivars. Generally, length and dry weight of radicle, length and dry weight of plumule in weed seeds from interference with Alvand and Sepahan, were lowest value, significantly. Sepahan cv in compared to other wheat cultivars, had highest negative effects on feral rye from the viewpoint of seed number with ability of germination. Also, it caused to severe reduction of most of weed seedling growth characteristics. Thus, aforesaid cultivar was appropriate for control of field pollution, in both the short and long time.

Potassium Chloride (KCl) is used as a source of nutrients in agricultural development and also used as relieve salinity stress. In order to study of mitigation effects of K+ in salinity (NaCl) at canola plant (Brassica napus L. Var Hayola330), an experiment was carried out at research green house college agriculture Ferdowsi University of Mashhad, Iran, 2011. The experiment was managed at factorial arrangement base on compeletly randomized design in three replication and treatments included: NaCl (0, 30, 60 and 90 mM) and KCl (0 and 20 mM). Results showed that applied 20 mM KCl and 30 mM NaCl treatment was increased traits as relative water content (RWC), photosynthesis, number pod per plant and 100 seed weight in compare of control. The maximum seed weight per plant with 1.21 g was obtain from applied 20 mM KCl and 30 mM NaCl treatment and the minimum of this trait was observed in zero mM KCl and 90 mM NaCl treatment. In high level of NaCl (30 and 60 Mm), increase application of KCl could not improve all traits. There was significant correlation between seed weight per plant and number pod per plant (r=55**), seed per pod (r=47*) and there was also significant positive correlation between grain weight per plant and biomass and photosynthesis traits. In addition results showed that application Potassium Chloride (KCl) have diverse behaviour in different level of salinity and was increased some traits in compare of control in any level of salinity.

Copper (Cu) and Zinc (Zn) are essential micronutrients that are classified as heavy metal. These elements play structural and functional roles in many metabolic processes in plants.In order to investigate the effect of different levels of Cu and Zn on some growth parameters, Cu and Zn concentration, essential oil content and yield thisresearch was conducted in afactorial experiment as completely randomized design (CRD) with three levels of copper (0, 5 and 25 mg/Kg CuSO4) and zinc (0, 10 and 50 mg/Kg ZnSO4) in three replicate in a calcareous soil under greenhouse condition. Results showed that, the main effect of Cu and Zn of root, Chlorophyll index (SPAD) and essential oil yield had significant effecton the Cu and Zn concentration in shoot and leaf area. The maximum Value of Leaf area (2935.13 Cm2) was obtained in Cu and Zn at 5 + 10 mg kg -1 and minimum amount (2061.57 Cm2) in Cu and Zn 25+50 mgkg -1.The maximum concentration of Cu in shoot was obtained in Cu25Zn10 (25.53 mgkg-1) and maximum concentration of Zn in Cu5Zn50 (153.42 mg kg-1). The highest essential oil yield (101.12 and 105.73 mg pot-1) was obtained in 5 mg Cu Kg -1 and 10 mg Zn Kg -1, respectively. The results of this experiment seems to Low concentrations of Cu and Zn instimulate growth, biomass and essential oil yield of basil herbs while high concentrations it can cause some toxic effects.

Forskolin is an effective compound found in Coleus forskohlii plant which has different therapeutic properties. In this research, production of forskolin and gene expression of 1-deoxy-D-xylulose-5-phosphate reductoisomerase (DXR) were investigated in C. forskohlii plant after treatment with different concentrations of copper elicitor (0; as control, 4, 8 and 16 mM) for 16 hours. Results showed that forskolin concentration is increased up to 8 mM in such a way that the concentration can be estimated 1.5 fold more than the control sample, which consisted with changes of DXR gene expression level. It has been proved that excess concentration of copper, causes triggering of reactive oxygen species that directly or mediated through others signaling molecules induce gene expression level of defensive system. Considering the defensive role of diterpens, it is proposed that increase in DXR gene expression level by copper elicitor leads to increase in forskolin concentration as protective compound against stresses.

The future climate change will alter crop-pest interactions and will affect on amount of crops production, therefore, it is essential to predict pest damage in future conditions. Crop growth models are a technique that researchers could use to study possible impacts of climate change on crops. Although several dynamic models have been developed in recent years, most of them are not generally evaluating impacts of climate change on crop-pest interactions. In the present study, an eco-physiological crop model has been developed to meet these objectives. Its general structure relating to basic crop growth and yield is largely based on LINTUL model, and is written in Fortran Simulation Translator (FST) environment. In this modeling, first, we added phonological development stage (DVS) to LINTUL for simulation of winter wheat growth and then the model calibrated for potential production level. Finally, we incorporate effects of sunn pest damages to winter wheat growth and yield. Parameter values were derived from the literature. The model validated against observed values of DVS, total dry weight yield (TDWY) and grain yield (GY) of winter wheat and winter wheat yield loss due to sunn pest taken from a field experiment. Results indicated that the model was able to explain successfully the observed differences in DVS, TDWY and GY. The loss in TDWY and GY due to sunn pest was also explained satisfactorily. Our simulation results showed that life cycle of winter wheat (from 240 to 217) will be shortened due to accelerate development rate under future climate. The impact of rising temperature on average GY of winter wheat in sunn pest densities was negative (about 47%) while the impact of elevated [CO2] was positive (about 36%) on it. Interaction of elevated [CO2] and temperature also had a negative effect (about 18%) on average GY of winter wheat in sunn pest densities. The impact of rising temperature was positive on sunn pest while the impact of elevated [CO2] had not any effects on it. Therefore, it seems that sunn pest damage on winter wheat growth and yield will be increased (about 7%) in the future climate compared to current climate.

Application of biofertilizers, especially plant growth promoting rhizobacteria (PGPR) and mycorrhiza fungus is one of the most important strategies for plant nutrition in sustainable management of agroecosystems. In order to investigate the effect of Azotobacter bacteria, mycorrhiza fungus and zinc sulfate on the growth and yield of fenugreek (Trigonella foenum- graecum), a field experiment as randomized complete block design with three replications was conducted at the Agricultural Research Farm of Shahrekord University during growing season of 2011. Treatments included: Control (C), urea fertilizer (UF), urea fertilizer+ zinc sulfate (UF+ZS), urea fertilizer+Azotobacte (UF+Az), urea fertilizer+ mycorrhiza (UF+My). Measured traits include yield, yield components, percent and yield of essence. The results indicated that the highest amount of plant height and number of branches were accomplished of fenugreek with biological fertilizeras. Application of biological fertilizeres and zinc sulfate significantly increased plant height, leaf area index . The greatest of 1000 seed weights (17 gr) was achieved in UF+ZS and UF+ZS+Mycorrhiza tretments (P£0.05). The grain yield in Uf+ZS and UF+Zs+My treated soils were 1.95 and 1.72 Mg/ha, respectively, more than others treatments (P£0.05). Also, UF+Az treatment has the greatest essence percent (14%). In general, it is concluded that the appliction of zinc sulfate and/or zinc sulfate+ mycorrhiza plus urea, can affect increase yield of fenugreek.

Abstract To investigate the effect of Azotobacter and Pseudomonas bacteria and different levels of nitrogen and phosphorus fertilizers on forage yield and quality of turnip (Brassica rapa L.), a field experiment was conducted at Rice Research Institute of Iran during 2012 growing season. The experiment was arranged base on randomized complete block design with 14 treatments and three replications. The experimental factors were including Azotobacter chroococcum strain 12 and Pseudomonas fluorescens strain 41 bacteria and four levels (0, 50, 75 and 100 percent of required nutrient) of nitrogen and phosphorus fertilizers. The highest amount of fresh and dry forage yield, quality characteristic in shoot and root of forage turnip obtained in integrated application of biofertilizers and chemical fertilizers, particularly, inoculation with A. chroococcum strain 12 + P. fluorescens strain 41 + 50% nitrogen and phosphorus fertilizer. Therefore, can provide to involve nitrogen and phosphorus of plant by integrated system of biofertilizers and 50% chemical fertilizer introduces as superior treatment and step to reduces chemical inputs consumption and realization of aims in sustainable agriculture.

To evaluate the effect of water stress on growth and grain yield of spring safflower (Carthamus tinctorious L.) at reproductive stage, an experiment as a split plot on the frame of randomized complete block design with three replications was performed in Bu-Ali Sina university research field in spring season of 1391. Water stress as the main factor consisted of three irrigation levels such as normal irrigation, no irrigation from %50 flowering stage (flowering stress) and no irrigation from start of the seeding stage (seeding stress) were placed in main plots, and six cultivars of safflower including PI, local Ajabshir, Mec11, Faraman, Zarghan6 and Sina as the second factor were compared in three levels of irrigation treatments. Results indicated that water stress caused a significant reduction in all traits except of number of lateral stem, plant height, number of heads per plant and harvest index. The most effect of water stress on the studied characters was observed at the flowering stage. Water stress at flowering and seeding stages also caused 59.81 and 29.80 percent reduction in seed yield compared to control (non stress). At the flowering stage, reduction of seed yield and oil yield was due to reduction in the number of seeds in head, 1000 seed weight, and at the seeding stage was because of decrease in 1000 seed weight. Sina and local Ajabshir had maximum and minimum seed yield and oil yield, respectively at the flowering and seeding stages.

In order to evaluate the effect of rootstocks on fruit flavonoid content (hesperidin and naringin) of mandarin, an experiment was conducted in a completely randomized block design with 3 replications. Eight rootstocks including sour Orange, Yuzu, Bakraee, Shangsha, Citromelo, Cleopatra, Troyer citrange and Poncirus were used for page mandarin. Also the variation of hesperidin and naringin amounts of five different mandarins including Unshiu, Clementine, Bam, Minneola tangelo and Dancy grafted on the Citrange rootstock were studied. Results showed that the highest amount of naringin was observed in fruit pulp grafted on Poncirus. On the contrary, no significant difference in the content of hesperidin was observed among different rootstocks. No meaningful difference in the content of naringin was observed in both pulp and skin of fruit under the effect of different rootstocks. It has been cleared that, the highest amount of hesperididin of pulp and skin was observed in Bam and Unshiu varietie 15.2 and 1.8 mg/100g FW srespectively. Based on the obtained results, it can be concluded that rootstock not only influences the morphological characteristics of plant, but also the nutritional and pharmaceutical properties of mandarin affect by rootstock. Based on the findings it seems that among studied cultivars Unshiu mandarin and among the rootstocks Poncirus able to produce the best pharmaceutically qualitative fruits.

Salinity is a major environmental stress, limiting plant growth and yield. Determining the extent of salinity tolerance in horticultural crops helps overcome the problem. In order to study the effects of salinity on yield and some physical and biochemical characteristics of strawberry “Camarosa”, an experiment was conducted in a greenhouse based on a completely randomized design with four replications. To trigger the salinity stress, half-strength Hoagland's solution containing 0, 7.5, 15, 30 and 45 mmol NaCl was applied for 45 d. The results showed that salinity stress significantly affected yield, fruit weight and number of fruits per plant. The highest yield, fruit weight and number of fruits per plant (106.46 g plant-1, 8.63 g and 12.25, respectively) were found in control plants and the lowest ones (54.51 g plant-1, 6.46 g and 8.31, respectively) were found in plants treated with 45 mmol NaCl. Salinity decreased RWC and chlorophyll content, and increased soluble carbohydrates and proline content. The amount of soluble proteins was 26.5% lower in plants treated with 45 mmol NaCl compared to controls. In total, fruit yield and most of the physical and biochemical characteristics of strawberry “Camarosa” in plants treated with NaCl to the level of15 mmol (EC=2.5 dS m-1) was not significantly different from those in controls (EC=1.2 dS m-1).

Festuca rubra and Lolium perenne are major cool-season turfgrasses which are used as turf grass around the world. Festuca and Lolium seeds were soaked for 12 h in distilled (Control) water and 100 mg l-1 SA. The seeds were sown in salinized soil mixture with 0, 40, 80 and 120 mM NaCl. The results showed that the seed germination percentage and germination velocity decreases significantly by increasing of salinity levels. Lolium was more tolerant than Festuca against salinity in germination stage. Stem length of Lolium was significantly higher than Festuca in saline and non-saline treatments. Stem length in both species were reduced under salinity conditions. Dry weights of both species were increased by salicylic acid application under saline and non-saline conditions. In conclusion, negative effects of salinity on growth were reduced by SA application.

Bacteria of the genus Azospirillum and mycorrhizal fungi, well known as plant growth promoting microorganism, are considered to can improve plant tolerance to environmental stresses such as drought and salinity conditions. A factorial randomized complete block design replicated in three times was conducted to test the effects of Azospirillum strains and fungus Piriformospora indica under increasing salinity levels on wheat seedlings growth, nutrient absorption as well as some physiological traits. Treatments were consisted of five bioinoculants (P. indica, salt adapted and non-adapted Azospirillum strains, dual inoculation of the both microorganisms and non-inoculated treatment as control) as well as four salinity levels (0.2, 4, 8 and 12 dS m-1). Singly or co-inoculation of wheat with P. indica and salt-adapted and non-salt adapted Azospirillum strains lead to a higher increase in grain yield, N and P concentrations, protein content as well as total photosynthetic pigments, both under salinity and normal conditions. Plant inoculated with salt-adapted Azospirillum spp., under salinity, had the higher nutrient uptake (P and N), protein content as well as total photosynthetic pigments. From obtained result of the present study use of endophytic plant growth promoting microorganism singly or in combination depend on induced salinity levels is different. Under non-salinity dual combination of both microorganisms was more effective in enhancing grain yield compared to other treatments. While under the lower level of salinity (EC=4) microorganisms, both in singly or in combination, had a same effect on grain yield, under severe salinity (EC=12) singly inoculation of each microorganisms had a better performance on grain yield.

Selenium (Se) is an essential element for humans and animals. However, its effects are less known on plants. In this study, the effect of different sources and levels of selenium was studied on growth and some physiological characteristics of onion in hydroponic system, it is done in order to have a good and an acceptable quality character, and does not have a problem for human and plant. The treatments included four levels of selenium nanoparticles (2, 5, 10 and 30 mgL-1) and three concentrations of sodium selenite (2, 4 and 8 mgL-1) and sodium selenate (1, 2, and 3 mgL-1), each treatment were separately performed in a completely randomized design with three replicates. Results showed that in seedling stage different levels of nano-selenium, sodium selenite and sodium selenate were significantly effected on leaf fresh weight, root fresh weight, root dry weight, pseudostem fresh weight and also bulb weight, bulb diameter and length of bulbs. Sodium selenite and sodium selenate were significantly effected on leaf chlorophyll content and total selenium bulb. The highest leaf chlorophyll content was observed at low levels of sodium selenite and sodium selenite by increasing selenium concentration in nutrient solution, leaf chlorophyll content were decreased in comparison with control. The content of total selenium bulb increased with increasing sodium selenite and sodium selenate concentration in nutrient solution, However increase in plants treated with sodium selenate was more than plants treated with sodium selenite.

Abstract The use of cuttings is one of the propagation techniques for Eucalyptus cloning. In this regard, cuttings of this plant root not simply and need usually some special hormonal treatments. A greenhouse experiment was conducted to evaluate the involvement between auxin and fertilization method in rooting process of Eucalyptus cuttings. In the present work, the influence of IBA (Indole-3-butyric acid) and bio-fertilizers on root initiation of Eucalyptus cuttings was investigated. A completely randomized design was adopted in a factorial experiment with five levels of IBA (0, 500, 1000,2000 and 4000 ppm) and four levels of bio-fertilizer (1- Barvar2 + half mineral fertilizer, 2- Nitroxin + half mineral fertilizer, 3-half mineral fertilizer and 4- complete mineral fertilizer) with five replications. The traits including: root number, root length, root fresh weight, root dry weight and rooting percentage were measured. Results showed a significant increasing in the trait expression using bio-fertilizers compared to using chemical fertilizer. The interaction between bio-fertilizer and IBA were significant for all investigated traits so that the application of relatively low doses of IBA concentration (500 ppm) with bio-fertilizers led to the greatest root dry weight and consequently, thicker roots were produced. Relatively high doses of auxin IBA concentration (2000 ppm) combined with bio-fertilizers resulted to the highest percentage of root initiation in cuttings. IBA concentration of 500 ppm caused increment in means of root dry and fresh weight. Thicker roots were produced, consequently. In spite of thicker roots, it was decreased risk of stock movement. The interaction between IBA 2000 ppm with both bio-fertilizers increased in rooting percentage. Therefore, these components with hormones enhance rooting capacity.