majid moslemi; hamidreza mobasser; nematollah sedaghat; eiman eshghi
Abstract
Optimizing the rate of nitrogen fertilizer application is one of the important management strategies for yield improvement. In order to investigate the effects of nitrogen levels & stress during two years on morphological characteristics & agronomic traits of rice, an experiment was conducted ...
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Optimizing the rate of nitrogen fertilizer application is one of the important management strategies for yield improvement. In order to investigate the effects of nitrogen levels & stress during two years on morphological characteristics & agronomic traits of rice, an experiment was conducted in the form of split plots in a randomized complete block design with four replications in 2009 & 2010 in a research farm located in Amol. Nitrogen levels at three levels (46, 69, 92 kg N / ha from urea source) as the main factor & sub-factor including four levels of stress or lack of nitrogen consumption (T1 = stress at full clustering stage, T2 = stress at stage the emergence of the initial cluster was T3 = stress at tillering stage and T4 = stress at transplanting stage). The results showed that number of full panicles per panicle, 1000-seed weight, Grain yield and harvest index in 2009 it was more than in 2010. Grain yield in the first year (450.25 g / m2) was higher than the second year (395.1 g / m2). Maximum harvest index was obtained in 2009 with nitrogen stress at full clustering stage. Therefore, the application of 69 kg of nitrogen in installments per hectare can be suggested to produce the highest grain yield.
nematollah sedaghat; Abbas Biabani; morteza nasiri; Allahyar Fallah; nahid fathi
Abstract
Water plays a very important role in the rice plant. In order to investigate the effects of irrigation methods and foliar application of nutrients on growth, yield, yield components, and quality of rice, an experiment has been conducted as split plots layouts based on a randomized complete block design ...
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Water plays a very important role in the rice plant. In order to investigate the effects of irrigation methods and foliar application of nutrients on growth, yield, yield components, and quality of rice, an experiment has been conducted as split plots layouts based on a randomized complete block design with three replications and two factors including three irrigation methods (flooding, alternate wetting, drying, and Saturating) in the main plots as well as foliar spray in six levels (normal water, nitrogen, nitrogen+ potassium, nitrogen+ potassium+ zinc, nitrogen+ potassium+ zinc+ boron and nitrogen+ potassium+ zinc+ boron+ molybdenum) in the sub plots during 2018, in rice research institute, the deputy of Mazandaran (Amol), executed on a national cultivar. Results show that among irrigation method, fertilizer, and their interaction, paddy yield and percentage of amylose have been significantly at (p<0.01) percent with other qualitative traits being significant at (p<0.01) percent. The highest number of floret per panicle (198.73) and full grain (167.15), and percentage of amylose (21.67%) are obtained in saturated irrigation. The highest yield of paddy with an average of 6643.07 kg.ha-1 occurs in saturated irrigation under normal water foliar application and drought and moisture. Irrigation under nitrogen + potassium + zinc foliar irrigation with an average of 6163.13 kg.ha-1 compared to the control is obtained as the superior treatment in similar conditions were selected for this study.
mohammad ali esmaili; Hbibollah Ranjebar; Hemmatollah Pirdashti; Mortaza Nasiri
Abstract
The field experiment has been conducted as a split split plot based on a randomized complete block design with three replicaitons at Rice Research Institute of Mazandaran Province, Amol, in 2017. In this experiment, the seeds are sown in seedling box with different six bed treatments. These beds include ...
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The field experiment has been conducted as a split split plot based on a randomized complete block design with three replicaitons at Rice Research Institute of Mazandaran Province, Amol, in 2017. In this experiment, the seeds are sown in seedling box with different six bed treatments. These beds include S1: sulfur bed with 50% rice bran, S2: sulfur-free soil with 25% rice bran, S3: sulfur bed with 25% rice bran, S4: sulfur bed with Thiobacillus and 50% rice bran, S5: sulfur-free bed with wood compost and 25% rice bran, and S6: sulfur bed with Thiobacillus with 25% bran rice. After some measurements, the seedling is transplanted in the main field. In the field, different beds in box, seedling number per hill (3 and 5) and planting space (20×20 cm, 30×14cm) are assigned to the main plot, sub plot, and sub sub plot, respectively. The results of main cultivation show that the highest grain yield (5043 kg.ha-1) and biological yield (12319 kg.ha-1) are obtained from the treatment of bed soil with sulfur with 50% bran. Planting arrangement treatment in ratoon cultivation on number of hollow seeds (4.1), grain yield (1617 kg.ha-1), number of plants per hill treatment on number of tillers (10.3), leaf area (10.6 cm2), panicle length (20.4 cm) and grain yield (1613 kg.ha-1), and seedling type treatment on tiller number (10.4) show a statistically significant difference. Seedling grown in sulfur with 50% rice brain display the best performance in terms of yield and yield components in both main and ratoon cropping.
Maryam Saraei; Morteza Moballeghi; Morteza Nasiri; Mojtaba Nashaeemoghaddam
Abstract
The remobilization of carbohydrates in shoots is one of the effective factors to grain filling in rice. To determine the contribution of dry matter remobilization of shoots in different rice genotypes, a research has been carried out with seven rice genotypes and two controls in RCBD design with three ...
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The remobilization of carbohydrates in shoots is one of the effective factors to grain filling in rice. To determine the contribution of dry matter remobilization of shoots in different rice genotypes, a research has been carried out with seven rice genotypes and two controls in RCBD design with three replications during 2017-2018 at rice research station of Shahid Shiroodi in Tonekabon county. Results show that among all genotypes, rate of dry matter remobilization via the flag leaf, stem, and total shoot has differed significantly at (p<0.01) percent and from other leaves at (p<0.05) percent level. Mean comparison among the genotypes indicates that the highest dry matter remobilization from flag leaf belongs to Genotype 952 with 56 g.m-2. The maximum carbohydrates remobilization in other leaves, stem and total shoots are assigned to Genotype 953 at 123, 230, and 398 g.m-2, respectively. Highest grain yield belongs to Genotype 952 with 7206 kg.ha-1. Correlation analysis results show that grain yield is positively and significantly correlated with dry matter remobilization from flag leaf, stem, and total shoots, as well as 1000-grain weight, having coefficients of 0.37, 0.55, 0.51, and 0.44, respectively. As a result of yield and dry matter remobilization rate, and the positive and significant correlation between them, both Genotypes 952 and 953 are suitable for continuing research activity and introduce a new rice cultivar especially in drought and hot stress conditions at the grain filling stage.
Seyfollah Halalkhor; Salman Dastan; Afshin Soltani; Hossein Ajam Norouzi
Abstract
Documentation process in agricultural production includes providing all information and activities that show the production route of one crop from providing stage of seed laying to harvest. For this purpose, in this research all finished managing operation from providing stage of seed preparation to ...
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Documentation process in agricultural production includes providing all information and activities that show the production route of one crop from providing stage of seed laying to harvest. For this purpose, in this research all finished managing operation from providing stage of seed preparation to harvest for local cultivars of rice was recorded trough fields studies in Mazandaran, Babol in 2015e2016. Result showed that from 155 variables under research, the final model with six independent variables was chosen. In yield model, maximum and average yield were 6489 and 4572 kg ha-1, respectively that estimated is comparable to observed average and maximum yield (4572 and 6489 kg ha-1). All estimated yield gap was equivalent to 1977 kg ha-1. The amount of yield increase result from yield difference of two variables of the best and average pest and weed problems were equals 7.3 per cent of total yield increase (140 and 59 kg ha-1), respectively. The amount of increase yield related to fallow variable equal’s 62 kg ha-1 includes three per cent of total yield increase. The quantity of yield increase related to the effect of Amrollahi cultivar and plant density was 375 and 367 kg ha-1, respectively which equals to 19 per cent of total yield variation. Therefore, on the basis of findings, we can state that the precision of the model was appropriate and can be applied for both the evaluation of the amount of yield gap and determining the portion of each restricting yield variables.
Borzo Kazerani; Saied Navabpour; Hossein Sabouri; Seyedeh Sanaz Ramezanpour; Khalil Zaynali Nezhad; Ali Eskandari
Abstract
To determine the best selection indices for facilitating the selection procedure in a reproductive stage of 96 mutant lines (M2) of rice under different moisture conditions, an experiment was carried out in two environments at the research farm of Gonbad Kavous University in 2016 base on randomized complete ...
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To determine the best selection indices for facilitating the selection procedure in a reproductive stage of 96 mutant lines (M2) of rice under different moisture conditions, an experiment was carried out in two environments at the research farm of Gonbad Kavous University in 2016 base on randomized complete block design with three replications. Evaluating the reduction percentage in the average values of traits showed that the most damages as affected by drought stress was due to decreases in numbers of filled grains, numbers of tillers, and 1000-grain weight. Results of stepwise regression analysis indicated that 1000-grain weight, plant height, numbers of filled grains, numbers of days to flowering, flag leaf rolling, numbers of tillers, and panicle length traits were respectively entered into the final multivariate regression model as important traits affecting grain yield under a flooded condition, and 1000-grain weight, numbers of days to flowering, plant height, fertility percentage, panicle length, flag leaf frying, and numbers of tillers were respectively entered under drought stress. Evaluation of direct and indirect effects of studied traits on the grain yield using a path analysis showed that, 1000-grain weight, due to a positive and high direct effect, and numbers of filled grains, due to an indirect effect via 1000-grain weight, can be considered as the most important traits for increasing the grain yield under flooded condition. However, 1000-grain weight and fertility percentage can be introduced as appropriate selection criteria for the grain yield under a drought condition.
Nahid Fathi; Hemmatollah Pirdashti; Morteza Nasiri; Esmaeil Bakhshandeh
Abstract
This study aimed to investigate the effect of different local climates on grain yield (GY) and yield components (YC) of two different rice cultivars (cvs. ‘Tarom Hashemi’ and ‘Shiroudi’) and also to quantify the relationships between GY and YC with the average of weather temperature ...
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This study aimed to investigate the effect of different local climates on grain yield (GY) and yield components (YC) of two different rice cultivars (cvs. ‘Tarom Hashemi’ and ‘Shiroudi’) and also to quantify the relationships between GY and YC with the average of weather temperature (T, °C) and solar radiation (SR, MJ m-2 d-1) during the growing season of rice. Three field experiments were conducted separately based on the randomized complete blocks design with four replications, at the paddy fields of Babolsar, Amol and Polesefid cities in northern Iran in 2014. The results indicated that the effect of different local climates were statistically significant on GY, the number of panicles, length of panicle, weight of panicle, total number of grain in each panicle and the number of filled grain (P < 0.01). In all traits, the values related to Polesefid were lower than both Amol and Babolsar which can be resulted in lower T and SR during the rice growing, especially in the reproductive stage. Decline in T and SR due to increasing in the above mean sea level were cased a decrease in GY and biological yield of both cultivars (about 10-25 percent, depending on the cultivar). In addition, GY was affected by decrease in T more than SR. Consequently, the results shown that we simply can quantify the variation in GY in both cultivars under different local climates and also can calculate a possible reduction in GY due to the delay in transplanting.
Farnaz Faraji; Masoud Esfahani; Mohammad Reza Alizadeh; Ali Alami
Abstract
In order to evaluate the morphological characteristics and lodging related traits and carbohydrate content of culm and carbohydrate remobilization in traditional and improved rice cultivars, a field experiment was laid out in randomized complete block design with three replications at Rice Research Institute ...
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In order to evaluate the morphological characteristics and lodging related traits and carbohydrate content of culm and carbohydrate remobilization in traditional and improved rice cultivars, a field experiment was laid out in randomized complete block design with three replications at Rice Research Institute of Iran )Rasht( in 2012 and 2013. Rice genotypes included three native rice cultivars (Hashemi, Sangjo and Alikazemi) and six improved (Kadous, Gohar, Khazar, Sepidrood, Deylam and Dorfak) and three promising lines (831, 841 and 416). On the basis of this results, the greatest amount of breaking resistance were observed in third and fourth internods of Khazar. Furthermore, significant positive correlation were observed between average diameter of internode, fresh weight/length of internode and unsoluble carbohydrate content of culm in anthesis and maturity stages with breaking resistance of third and forth internods. Also, significant positive correlation was observed between number of parenchyma cells and unsoluble carbohydrate content of culm in anthesis and maturity stages. On the other hand, there was significant negative correlation between carbohydrate remobilization and breaking resistance of third and forth internods. Principal component analysis classified plant characteristics to two groups. The first factor was named as lodgigng resistance factor and included 71.01 percent of total variation. The second factor with 19.74 percent of total variation was named as morphological lodging sensitivity factor. According to the results of this experiment, it seems that average diameter, thikness and weight/length of internode, have major roles in rice plant resistance to lodging.
Atena Gholipur; Mehdi Ghajar sepanlu; Mohammad ali Bahmaniar
Abstract
In order to study the effect of municipal solid waste application with or without chemical fertilizer on the concentration of heavy metals in soil and rice plant, an experiment was conducted with randomized complete block design in three replications and fourteen treatments in Research Station of Sari ...
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In order to study the effect of municipal solid waste application with or without chemical fertilizer on the concentration of heavy metals in soil and rice plant, an experiment was conducted with randomized complete block design in three replications and fourteen treatments in Research Station of Sari Agricultural and Natural Resources University in 2009 and 2010. The treatments included control treatment, chemical fertilizer, 15, 30 and 45 ton/ha municipal solid waste compost and chemical fertilizer at three levels (25, 50 and 75 percent). Results indicated that applying compost for two years showed no significant effect on any of the available heavy metals in soil. However, significant increases were observed for Lead (Pb2+) in root, and Pb2+, Cd2+, Nicle and Cobalt in shoot and Cadmium (Cd2+) in grain. Meanwhile, the highest amount of heavy metals was concentrated in 45 t/ha of municipal solid waste + 75 percent chemical fertilizer treatment. Thus, using municipal solid waste compost, the amount of the heavy metals increased in soil and rice plant but their concentrations were below their toxicity limit.