Journal of Crop Ecophysiology: 4 (47)

Open Access Article

1 - Evaluation of AquaCrop Model in Simulating Yield and Water Use Efficiency of Three Corn Hybrids under Hot-Dry Climatic Conditions
Yaser Esmaeilian Mahmoud Ramroudi

Nowadays, crop simulation models have a key role in crop growth and yield estimation, production planning, production economy and identifying strategies for crops supply. In this research, AquaCrop model was calibrated and evaluated for three corn hybrids; (DC 370, ZP 6 More

Nowadays, crop simulation models have a key role in crop growth and yield estimation, production planning, production economy and identifying strategies for crops supply. In this research, AquaCrop model was calibrated and evaluated for three corn hybrids; (DC 370, ZP 677, and SC 704) under different levels of water supply (non stress, mid stress, and severe stress) and nitrogen rates (0, 120, 180, and 240 kg N/ha). For model validation, normalized root mean square error (nRMSE) and determination of coefficient (R2) were used. Result showed that the model simulated grain yield of corn hybrids with high precision. Simulation precision decreased with increasing drought stress. The lowest nRMSE (7.5%) and highest R2 (0.93) were obtained from ZP 677 hybrid. The model simulated corn biological yield with more deviation percentage than grain yield. However, it´s variation trend due to variation in drought stress level or nitrogen fertilizer predicted well according to field experiment. nRMSE ranged from 6.8 and 10.9, while R2 varied from 0.82 to 0.92. AquaCrop model simulated the variation of water use efficiency of corn hybrids with reasonable accuracy, so that it´s value increased with increasing drought stress and nitrogen fertilizer application, while, model outputs in most situations were lower than measured values. The best model validation result (nRMSE=6.4% and R2= 0.93) obtained from ZP 677 hybrid. According to the results were obtained, AquaCrop model can be applied with high reliability for simulating corn yield under similar climatic regions of this experiment. Manuscript profile

Open Access Article

2 - Simulation of Some Optimal Traits Related to Rain-Fed Wheat Yield at Urmia Conditions
Nabi Khalili agdam

For assessment of yield changes of wheat (cv. Sardari) and 14 modified genetically cultivars, a simulation experiment was conducted to select optimal plant characteristics based on maximum leaf area index, biomass of seed at filling time, biological yield, seed yield an More

For assessment of yield changes of wheat (cv. Sardari) and 14 modified genetically cultivars, a simulation experiment was conducted to select optimal plant characteristics based on maximum leaf area index, biomass of seed at filling time, biological yield, seed yield and harvest index, using SSM-Model in rain-fed conditions of urmia for 3 years (2011-2013). Results of simulations showed that the major effective parameter in increasing of grain yield was 20% decreasing in time till grain filling beginning (vegetative phase), 20% increasing in time till grain growth ending and 30 % inversing in radiation use efficiency. The maximum leaf area index, the highest biomass at grain filling time, biological yield, grain yield and harvest index were determined in modified cultivars like: C2, C12, and C8 respectively which was made by increasing in vegetative phase, upgrading of flowering phase (grain filling phase) and improvement of radiation use efficiency (RUE). In cluster analysis which was used by three methods (mean linkage, single linkage and centroid), three groups were obtained: C12 and C8 in group 1, C11 in group 2 and other cultivars in group 3(C1, C2, C3, C4, C5, C6, C7, C9, C10, C13, C14 and Sardari). Recognition analysis of functions indicated that the main effects on clustering of genotypes are LAImax and biomass at the beginning of seed growth. Results, as a whole, showed that it is necessary to take into account climatically changes, methods of increasing of grain filling period, earlier enterance to grain filling period and improvement of RUE in addition to achieving optimum LAI during vegetation growth period in wheat, because it could be the important impacts in increasing of grain yield of wheat. Manuscript profile

Open Access Article

3 - Effect of Drought Stress and Straw Mulch of Wheat on Morpho-Physiological Characteristics of Sesame
Jahanbakhsh Behzad Nejad Zeinolabedin Tahmasebi Sarvestani Ahmad Aien Ali Mokhtassi Bidgoli

To study the response of sesame plant under water deficit condition to the management methods, a factorial split experiment using a randomized complete block design with three replications was conducted at the Jiroft Agricultural and Natural Resources Research and Educa More

To study the response of sesame plant under water deficit condition to the management methods, a factorial split experiment using a randomized complete block design with three replications was conducted at the Jiroft Agricultural and Natural Resources Research and Education Center in 2015. Irrigation treatments were soil field capacity, permanent wilting point, root development depth and percent availability water to sesame (with four levels: 100, 80, 60 and 40% of the required water). Ecotypes used, were Halil, Borazjan 2 and local population of Jiraft. In this experiment, wheat straw mulch used with two levels: (without using mulch and using 7.5 tons of mulch per hectare). The results showed that simple effects of drought stress and mulch and the interaction of drought stress × mulch on all measured traits were significant at the probability level of 1%. The interaction of drought stress × ecotypes × mulch was significant only for number of branches and oil percentage. The highest and lowest seed yield and oil percentage were belonged to Haleil and Borazjan 2 ecotypes, respectively. Use of 7.5 tons straw mulch per hectare resulted in improving the means of measured traits as compared to that of control. The highest percentage of oil was obtained from Halil ecotype by using straw mulch and irrigation level of 100% (53.10%), but its difference with irrigation level of 80% (52.9%) was not significant. In general, the results showed that the using of straw mulch of wheat reduced positively the effects of water deficits. Manuscript profile

Open Access Article

4 - Effect of Water Deficit Stress and Seed Biopriming on the Physiological Indices and Antioxidant Activity of Tansey (Tanacetum persicum (Boiss.) Mozaff)
Fatemeh Bahmeh Abdolrazagh Danesh-Shahraki Zahra Lorigooini Mahdi Ghobadinia

Growing medicinal plants is important for utilizing their drug precursors, and preserving the genetic resources and diversity in the ecosystem. Tansyis one of the medicinal plants with its valuable therapeutic and antioxidant properties. To investigate the effect of pla More

Growing medicinal plants is important for utilizing their drug precursors, and preserving the genetic resources and diversity in the ecosystem. Tansyis one of the medicinal plants with its valuable therapeutic and antioxidant properties. To investigate the effect of plant growth promoting rhizobacteria on the physiological indices and antioxidant activity of tansyunder water deficit stress, a factorial pot experiment was conducted in a randomized complete block design at the Experimental Farm of Shahrekord University in 2016. The factors consisted at water deficit at three levels: full irrigation (control), 75% full irrigation and 50% full irrigation; and seed biopriming treatments at seven levels: non-bacterial inoculation (control), Azotobacter chroococcum, Bacillus amyloliquefaciens, Bacillus sp. strain A., Bacillus sp. strain B., Pseudomonas fluorescens and Pseudomonas putida. The results showed that bacterial inoculation treatments had a significant effect on all of the analyzed traits (p≤0.01). Azotobacter chroococcum inoculation had the most significant effect on chlorophyll a and carotenoids contents, biological yield, essential oil yield, and anthocyanin contents (0.020 µmol.ml-1). Bacillus sp. strain A showed a 2.5-fold increase in proline content compared to that of control, and Bacillus sp. strain B had the greatest effect on antioxidant activity (IC50 5.32 μg.ml-1). Moreover, Pseudomonas fluorescence increased the carotenoids content in 50% full irrigation treatment, and Pseudomonas putida had the highest effect on chlorophyll b and total chlorophyll contents, membrane stability, and leaf relative water content. The results revealed that the inoculation of Tansyseeds with Azotobacter and Pseudomonas bacteria, especially in deficit irrigation practices, is recommended to alleviate the adverse effects of water stress. Manuscript profile

Open Access Article

5 - Effect of Foliar Application of Iron on Growth, Nodulation and Quantity and Quality of Yield of Chickpea (Cicer arietinum) in Hamedan
Javad Hamzei Mohsen Seyedi Afshar Azadbakht Ayob Fesahat

This research was carried out at the Research Farm, Faculty of Agriculture, Bu-Ali Sina University for two growing seasons (2011-2012). The aim of research was to evaluate the effect of foliar application of iron on growth, nodulation and quantity and quality of chickpe More

This research was carried out at the Research Farm, Faculty of Agriculture, Bu-Ali Sina University for two growing seasons (2011-2012). The aim of research was to evaluate the effect of foliar application of iron on growth, nodulation and quantity and quality of chickpea yield in Hamedan. A randomized complete block design with three replications and seven treatments were used (T1: control; non-foliar application, T2: foliar application of 2 g.L-1 of nano fertilizer at flowering stage, T3: foliar application of 4 g.L-1 of nano fertilizer at flowering stage, T4: foliar application of 2 g.L-1 of nano fertilizer at podding stage, T5: foliar application of 4 g.L-1 of nano fertilizer at podding stage, T6: foliar application of 2 g.L-1 of nano fertilizer at flowering and podding stages and T7: foliar application of 4 g.L-1 of nano fertilizer at flowering and podding stages). The effect of treatments on the most traits was significant. Based on means comparisons, lower values for traits like number of pods per plant, number of grain per plant, 1000-seed weight, biological and seed yields, number and dry weight of root nodules and iron content of seed and protein percent were obtained from control (non-foliar application) and foliar application 4 g.L-1 of nano fertilizer at flowering and podding stages treatments. The highest biological yield (329 g.m-2), seed yield (152 g.m-2) protein percent (27.85%) were obtained from treatment of foliar application of 4 g.L-1 of nano fertilizer at flowering and podding stages. Therefore, foliar application of 4 g.L-1 of nano-iron chelate in both flowering and podding stages produced the highest root nodulation, agronomic indices and seed yield. Manuscript profile

Open Access Article

6 - The Effects of Using Organic and Biological Fertilizer Along with Lower Rate of Chemical Nitrogen Fertilizer on Quality and Quantity of Rice Yield
Norollah Kheyri Yousof Niknejad Maryam Abbasalipour

To investigate the possibility of increasing the quantity and quality rice yield (var. Tarom Hashemi) by application of organic and biologic fertilizers with lower rate of chemical nitrogen fertilizer, a field experiment was carried out in a randomized complete block de More

To investigate the possibility of increasing the quantity and quality rice yield (var. Tarom Hashemi) by application of organic and biologic fertilizers with lower rate of chemical nitrogen fertilizer, a field experiment was carried out in a randomized complete block design with eight treatments and three replications in Amol in 2014-2015. Experimental treatments were: T1: control or no fertilizer application, T2: nitrogen fertilizer application of 46 kg.ha-1, T3: azolla compost application of 10 ton.ha-1, T4: vermicompost application of 10 ton.ha-1, T5: nitrogen fertilizer of 23 kg.ha-1 + azolla compost of 5 ton.ha-1, T6: nitrogen fertilizer of 23 kg.ha-1 + vermicompost of 5 ton.ha-1, T7: azolla compost of 5 ton.ha-1 + vermicompost of 5 ton.ha-1 and T8: nitrogen fertilizer of 12 kg.ha-1 + azolla compost of 5 ton.ha-1 + vermicompost of 5 ton.ha-1. Results showed that the percent of sterile floret per panicle increased (13.95%) by not using fertilizer. The highest panicle length (25.47 cm), number of fertile tiller per hill (18.30) and filled grain number per panicle (136.1) belonged to treatment no. T8. Treatments of T3 and T4 resulted in highest 1000-grain weight. The highest grain yield (5295 kg.ha-1) was produced by combined application of nitrogen fertilizer, azolla compost and vermicompost. This was due to the increased panicle length and yield components such as number of fertile tiller per hill and filled grain number per panicle. Amylose content decreased under the combined treatments. The optimum range of gelatinization temperature (ranging between 3 to 5) were observed only in treatments containing chemical nitrogen fertilizer. According to the results of this research, the treatment no. T8, due to reduced nitrogen chemical fertilizer application and its lower environmental impacts was considered to be the best treatment for increasing the grain yield of rice. Although, the combined application of nitrogen with any of the biologic or organic fertilizers, especially azolla, had a significant effect on improvement of seed yield. Manuscript profile

Open Access Article

7 - Effects of Mycorrhizal Symbiosis along with Vermicompost and Tea Compost on Quantity and Quality Yield of Mentha aquatic L.
Mostafa Koozehgar Kaleji Mohammad Reza Ardakani Naser Khodabandeh Mojtaba Alavi Fazel

To evaluate the effect of organic fertilizers and mycorrhizal symbiosis on yield components and percentage of essence of Mentha aquatica, a factorial experiment based on a randomized complete block design with 8 treatments and 4 replications was conducted in Sari, in 20 More

To evaluate the effect of organic fertilizers and mycorrhizal symbiosis on yield components and percentage of essence of Mentha aquatica, a factorial experiment based on a randomized complete block design with 8 treatments and 4 replications was conducted in Sari, in 2014. The experimental treatments were mycorrhizal fuangi (Glomus mosseae) with two levels (0 and 10% per pot), vermi-compost with two levels (0 and 10% per pot) and compost of tea with two levels (0 and 1.5 liter per pot). The results showed that use of organic fertilizer and mycorrhizal symbiosis significantly improved the quantity and quality characters Mentha aquatica. Use of organic and biological fertilizers had a significant effect on most of the measured traits and increased all of the traits as compared to those of control. Thus, highest plant height, leaf number, seed number per plant, plant dry weight, root length, root diameter, leaf area index, essence present and essence yield were obtained by using mycorrhizal symbiosis and compost tea, vermin-compost as compared to those of control treatment. Generally, the use of organic and biofertilizers, produced optimum quality and quantity of Mentha aquatica. In fact, increased performance of organic and biological fertilizers improved the activity of plant growth regulators and reduced elemental leaching and thus resulted in higher absorption of nutrients, increased plant growth, seed yield and essential oil content of Mentha aquatica. Manuscript profile

Open Access Article

8 - Possible Use of the Chlorophyll Meter for Diagnosing Nitrogen Deficiency in Early Growth Stage of Tobacco under Field Condition
Mohammadtaghi shamelrostami Abbas Biabani Abdollatif Gholizadeh Hosein Sabouri Ebrahim Golamalipour Alamdari

Nitrogen is one of the most essential nutritional element in growth and a determining factor in tobacco yield. Therefor, rate and timing of nitrogen application is very important for growth of this plant. The purpose of this study is to use SPAD values to estimate nitro More

Nitrogen is one of the most essential nutritional element in growth and a determining factor in tobacco yield. Therefor, rate and timing of nitrogen application is very important for growth of this plant. The purpose of this study is to use SPAD values to estimate nitrogen usage through correlation of SPAD value with yield and quality traits at different growth stages of tobacco. This study was conducted in a randomized complete block design on flue cured tobacco (K-326 cultivar) in Tirtash Tobacco Research and Education Center for two years (2015 and 2016). Treatments consisted of three nitrogen level (20, 40 and 60 kg.ha-1) and three application methods of nitrogen (1- two parts of nitrogen broadcasted before planting + one part of nitrogen as side dressing, 2- one part of nitrogen before planting + one part as first side dressing + one part as second side dressing, 3- two parts of nitrogen fertilizer as strip application + one part as side dressing) and a control (without fertilizer treatment). Chlorophyll meter (SPAD-502) was used in 40, 50 and 60 days after planting for greenness of lower, middle and upper leaves and various parts of the leaves (top, middle and bottom). During the growing season, length and width of upper, middle and lower leaves, green and dry leaf weights, average price and gross income were determined. The results showed that green and dry leaf weights were increased by increasing nitrogen application and this was significant at %1 probability level. The highest correlation between SPAD value and upper leaves yields of 40 days transplanting was R2=0.86 and middle leaves yield after 50 days of transplanting was R2=0.89 which were the best leaves for estimating tobacco nitrogen usage. Average price of tobacco was decreased as nitrogen use increased and highest gross income was obtained by using 20 kg nitrogen with 3 split applications. Manuscript profile

Open Access Article

9 - Improvement of Seed Germination, Seedling Vigor and Yield of Achillea santolina and A. millefolium by Physical Priming Techniques
Bahram Mirshekari

To study the effect of physical primings on growth and yield of Achillea santolina and A. millefolium two experiments were conducted in Islamic Azad University of Tabriz, Iran, with three replications during 2014. Treatments were ultrasonication, laser, magnetic field, More

To study the effect of physical primings on growth and yield of Achillea santolina and A. millefolium two experiments were conducted in Islamic Azad University of Tabriz, Iran, with three replications during 2014. Treatments were ultrasonication, laser, magnetic field, gamma and beta radiations for 5, 10 and 15 min. along with a control. By increasing ultrasonic exposure time of Achillea santolina seed its germination was delayed. Seeds treated with ultrasonic wave for 5-10 min. and laser for 5 min. produced seedlings with higher vigors. Seeds of A. millefolium hydroprimed germinated only by 65%. Also, seeds of plants treated by magnetic field, gamma and beta radiations produced weaker seedlings. Achillea santolina plants treated by ultrasonic waves produced higher essence percentage. Essence yields of seeds of both species expesed to ultrasonic wave and laser were higher than the other ones. The effects of seedling vigor index and number of secondary branches on yield of both species were 1.90 and 1.85 times greater than that of final germination percentage. Ultrasonication and laser treatment of Achillea seeds resulted in both strong seedlings and higher essence yields. Manuscript profile

Open Access Article

10 - Critical Period of Weed Control of Corn (Zea mays L.) Second Cropping at Moghan Region
Saber Aley Ghorban Didehbaz Moghanlo Farid Golzardi

Moghan region, North West of Iran, is one of the important producers of the corn in the country. To determine the critical period of weed control in corn as second crop in this region, an experiment was carried out in a randomized complete blocks design with four replic More

Moghan region, North West of Iran, is one of the important producers of the corn in the country. To determine the critical period of weed control in corn as second crop in this region, an experiment was carried out in a randomized complete blocks design with four replications during 2010 in the Parsabad Moghan climatic conditions. Two methods of weed control treatments were used. In the first method, weeds controlled at 0, 10, 20, 30, 40, 50 and 60 days after corn emergence. (DAE), and then weeds were allowed to grow until harvest and in the second method of weed control, weeds were allowed to grow during 0, 10, 20, 30, 40, 50 and 60 DAE, and then the plots were kept free of weeds until harvest. The regression was used to determine the relationship between yield and different control periods and weed interference. The results showed that periods of weed- free and weed- infested plot affected differently the dry weight and number of weeds in all treatments. Generally the results showed that critical period of weeds control in corn (AYL) based on growing degree days (GDD) after sowing considering 5% acceptable yield loss, it is necessary to control weeds in a period between 1-67 days after planting or 90-1051 growing degree days and period of weeds control in corn (AYL) based on growing degree days (GDD) after sowing by considering 10% acceptable yield loss, weed control is necessary between 3-52 days after planting or 132- 844 growing degree day. Manuscript profile

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