مجله تولید گیاهان زراعی
سال هشتم شماره 2 (تابستان 1394)

er to investigated the effect of flooding, different nutrition levels an anti-oxidant characteristics, chlorophyll fluorescence, amount of chlorophyll (a, b) and Carotenoids leaves Soybean (Glycine max (L.) Merr), cultivar DPX research at the University of Agricultural Sciences and Natural Resources, Gorgan, in a completely randomized design to factorial arrangement with three replications was done in 2012. The experiment consists of three levels of nitrogen nutrition treatments factor (1 – non inoculation plus nitrogen fertilizer 2 - inoculated with bacteria (Bradyrhizobium japonicum) 3 - non inoculation without fertilizer) and flooding stress in four levels (0, 5, 10 and 15 days). Maximum enzyme activity of Ascorbate peroxidase was in first treatment (non inoculation plus nitrogen fertilizer) in flooded on day zero. Peroxidase and Catalase enzyme activity at all levels of the nutrition flooded up to 5 days at 10 and 15 days showed an increasing trend, but the flooding had reduced the activity of two enzymes. Flooding during the production of Ascorbic acid (from 0 to 15 days) was increased at all three levels of nitrogen nutrition. The amount of chlorophyll fluorescence, amount of chlorophyll (a, b) and Carotenoids showed a decreasing trend during flooding. Reduce the amount of chlorophyll a, was much more chlorophyll b. overall to intensity increases flooding increased activity of free radical resistance mechanism fall continues, the more damage will be flooded with increasing time.

Change in the method of crop establishment from traditional manual transplanting of seedlings to direct‐seeding has occurred in many Asian countries in the last two decades in response to rising production costs. Change of rice establishment methods as well as water management practices, tillage and weed control strategies in direct seeded-rice can leads to change in the composition and diversity of the flora of weeds. Also, Greater number of weed species in direct‐seeding of rice can reduce the effectiveness of strategies to manage weeds. Therefore, this work was conducted with the objective of evaluating the performance of some post-emergence herbicides and different row spacing for weed control in direct-seeded rice. Experiment was conducted in a factorial arrangement using a randomized complete block design with three replications during 2011-2012 growing season. Factors consisted of crop spacing between the rows in three levels of 15, 25, and 35 cm and seven weed control methods including application of six herbicide treatments (pendimethalin, bentazon, propanil + cinosulfuron, oxadiargyl, clodinafop propargyl + "bromoxynil + MCPA" + bentazon and sethoxydim + "bromoxynil + MCPA" + bentazon) and weed-free treatment. The plots were divided into two sections, treatments were applied in a section and the other part of each plot was considered as the control of treated section. The loss of maximum leaf area index, total dry matter and maximum growth rate of rice caused by the use of bentazon (an average of 68%) and oxadiargyl (an average of 84%) herbicides were significantly greater than the application of pendimethalin (an average of 47%) and herbicides mixtures (an average of 41%). Also, the lowest reduction of rice growth indices in competition with the weeds was observed in 15 cm row spacing (an average of 44%). Row spacing significantly influenced the yield and yield components of rice. As, the lowest rice yield reduction was recorded in 15 cm row spacing (83%). Effects of none of the herbicide treatments on rice yield were similar to the weed-free treatment. However, the rice yield losses with herbicides mixtures of sethoxydim + "bromoxynil + MCPA" + bentazon (56%), propanil + cinosulfuron (59%) and clodinafop propargyl + "bromoxynil + MCPA" + bentazon (59%) were significantly lower than obtained yield reduction with the application of other herbicides (an average of 86%). Application of herbicides mixtures evaluated in this study caused lowest differences between growth indices and yield of rice in comparison to weed-free control treatment. In this study, the rice yield loss in weed-infected plots was about 98 percent. Considering the yield loss in the absence of weed control, it is appears that to be satisfactory the yield loss obtained by only once application of herbicides mixtures during the growing season.

Food security has been most important concern of the mankind on the earth. On the other hand, agricultural productions have always been face by risk probability in the case of weather and changes in international markets, however this risk probability never undeleted completely, but could be minimized that by pre-harvesting yield estimation. In this study, different methods of vegetation maps provision were involved toprovide a suitable pre-harvesting map for wheat yield.

For comparison of remote sensing and geostatistics-based methods capabilities in wheat yield predication in wheat fields, a survey was conducted in 2011-12 growing season. 101 plant samples were taken from 2500 hectare wheat fields in tillering, booting, seed filling and maturity stages (three times for leaf area index and dry weight and one sampling for yield) and related measurements were done. Ordinary, Universal and Disjunctive Kriging methods were applied and semivariograms were provided, then proper models were fitted. Different statistical indices were used to test the accuracy. Also, three +ETM images acquired by Landsat satellite were used which were matched by sampling dates. Four images for previous years also were used as needed. Eight plant indices were provided from aforementioned images and were compared with plant variables which were recorded or measured simultaneously, then related relations were determined and maps were provided. By fitting the logistic model between yield and plant variables, yield prediction maps were evaluated by remote sensing and, the obtained maps were compared using different statistical indices.

Evaluation results of interpolation methods revealed that spherical, exponential, Gaussian and circular models were superior models in this study. Also, results on the survey indices derived from satellite images showed a significant relationship between the variables and indices derived from satellite images in the end of tillering stage. Assessment of generated yield maps, demonstrated pronounced superiority of remote sensing techniques compared with geostatistical-based analysis methods. The results demonstrated the capability of satellite images in regional scale to predict wheat yield (with 715 kg.ha-1 biass in tillering stage).

According to the acceptable accuracy of the remote sensing compared with the Geostatistics- based method along with ease of and low cost of this method, use of the remote sensing and satellite images – derived vegetation indices could be a new horizon in regional yield estimation. Since satellite images provide an actual representation from the crop status, could involve significantly to the growth modeling.

inFunction of the photosynthetic apparatus of halophytes plays an important role in their salinity tolerance. Kochia as a halophyte, is of high ability in biomass production in salinity stress conditions. Thus study photosynthesis and the related factors salinity stress can provide appropriate physiological view for better understanding of the plant mechanisms of in stress conditions. So a field experiment for evaluation photosynthesis and related factors at salinity stress in the real condition was done. So an experiment was conducted as split-plot based on Complete Randomized Block Design with three replications to evaluate some photosynthetic characteristics of halophyte plant, Kochia scoparia, in different salinity levels at the Salinity Research Station of Ferdowsi University of Mashhad, Iran in 2009. Salinity as the main plot had two levels of 5.2 and 16.5 dSm-1 and five kochia ecotypes including Urmia, Isfahan, Borujerd, Birjand and Sabzevar were allocated as sub-plots. Results indicated that increased salinity level had significant effect on stomatal conductance, transpiration and photosynthetic activity. With increasing levels of salinity from 5.2 to 16.5 dSm-1, stomatal conductance, transpiration rate and photosynthesis activity increased 29%, 0.41 mM.m-2 and 22.5% respectively. In the other hand increased salinity level had no significant effect on chlorophyll a, chlorophyll b, carotenoids content, spad, Ci, quantum yield of photosystem II, biomass, water use efficiency and potassium and sodium concentration in leaf and stem. There were significant effect observed between ecotypes in water use efficiency and potassium and sodium concentration in leaf and stem. Urmia and Borujerd with 52.7 percent different respectively, minimum and maximum in stem sodium and 75 percent different respectively had highest and lowest in leaf sodium. Interaction between salinity levels and ecotypes showed the significant effect only in stomatal conductance and water use efficiency. Stomatal conductance increasing in all ecotypes, except of Sabzevar ecotype with increased salinity, this rate of increase in Birjand, Borujerd and Urmia, ecotypes respectively 64.9, 39.0, 38.8 and 13.0 percentage. water use efficiency increased by increasing salinity in Urmia and Boroujerd ecotypes and in other ecotypes, this trend were decline and Isfahan ecotype has highest decline rate. Significant correlation observed between chlorophyll a with chlorophyll b, carotenoids and total pigments in 5.2 dSm-1. Among the photosynthetic pigments, chlorophyll a to chlorophyll b ratio, showed a positive significant correlation with biomass. Generally, the variation of photosynthetic characteristics responses to salinity stress in Kochia ecotypes was high which increases the possibility of using these characteristics in breeding programs.

In order to evaluate the effect of some qualitative traits of sugar beet (Beta Vulgaris L.) under irrigation water quality and different types of fertilizers, a field experiment arranged as split plot in RCBD design with three replications at Research Station of Shahrekord University in 2013. The main factor include irrigation with urban wastewater at 2-4 leaf stage, 8-12 leaf stage and irrigation with tap water (control) and four types of fertilizer include sheep manure, spent mushroom compost, chemical fertilizer and no fertilizer (control) in sub-plot. The results showed that the plot irrigated with urban wastewater at 8-12 leaf stage significantly increased root potassium, α- amino-N, root yield and sugar yield of sugar beet compare to plot irrigated with tap water. But irrigated the plot with urban wastewater not significantly affected on the root sugar content. Besides, the maximum alcalite were belong to irrigation with tap water. Among all fertilizer treatments, the maximum root potassium, α- amino-N, root yield and sugar yield were belong to application of sheep manure and also, the highest sugar content was belong to the treatment of spent mushroom compost. Spent mushroom compost compare to sheep manure leads to significantly decrease of α- amino-N in root sugar beet.

Leaf rolling, especially in cereals, Mechanisms for reducing the light receiving surface of the leaves to reduce transpiration rate in response to drought caused. To investigate the effect of drought stress on leaf rolling and leaf anatomical characteristics, Yield and yield components in field experiment was conducted Bahonar University. In this experiment, five varieties of wheat (Shole, Omid, Azar2, Shahpasand and Azadi) and two levels of irrigation (optimum irrigation, water stress at vegetative stage) in a split plot design in randomized complete block design with three replications were compared. The results showed that under drought stress area and the number of cells Baliform, leaf thickness, specific leaf area, yield and spike, number of grains per spike and grain weight decreased while increasing leaf rolling. Due to the significant negative correlation between leaf rolling and grain yield and number of spikes per unit area, Leaf rolling in the Shahpasand reduced the number of grains per spike and grain yield than the other varieties. While the Azar2 with leaf rolling, because of negative impact of drought stress on specific leaf area, and also, the effect of less Undesirable effects of stress on the number of seeds per spike and number of spikes per unit area compared to other varieties, The higher grain yield.

To predict growth and yield, it is needed to study sub-models of phenology, dry matter production and partitioning, leaf area and soil water balance. In the present study, for predicting yield of faba bean under Gorgan conditions, parameters of sub-models were estimated using data of planting dates in Gorgan and data of other researchers in different regions of world. Daily variations of phenology, dry matter, leaf area and soil water balance were estimated using model and then final yield was predicted at the end of the growth season. Observed yields were between 2500 and 4520 Kg/ha, with average yield 3422 Kg/ha; while the predicted yields were ranged between 2820 and 3950 kg/ha, with average yield 3478 kg/ha. In this study, all points were in the rang of 85% from 1:1. The value of R2 was 0.67. In addition, values of RMSD and CV were 521 kg/ha and 3.9%, respectively. Therefore, it was concluded that this model has suitable precision for predicting yield under Gorgan conditions.

Quinoa (Chenopodium quinoa Willd.) is a member of Amaranthaceae family that originated in the Andean region in Bolivia, Chile and Peru five thousands of years and it has a tiny and round seeds. Quinoa indifferentcombinations of diet used as food, as well as how to cook like rice grains and known as the Inca rice in the South American countries. World Food Organization compared quinoa with dry milk because of its high nutritional value. According toquinoa tolerance to drought and salinity, the most important factor that quinoa suitable for cultivation in arid and desert-prone culture is early maturity because at the end of the growing season, drought is a major problem for quinoa culture, early maturity is an important strategy to reduce drought effects. In order to identify the variety with higher yield and early maturity, five genotypes of the quinoa include of Ames13737 (QA1),Ames13724 (QA2), PI634919 (QP1), PI51055 (QP2) and PI665272 (QP3) havereceived from National Salinity Research Center and planted in Agricultural Sciences and Natural Resources of Gorgan university under greenhouse condition in a completely randomized design with five replications. Some different morphophenological traits related to yield (1000- grain weight, plant height, stemheight, ear no. per main inflorescence and stem diameter) and early-maturity (germination (days), days to 4-leaf stage, days to inflorescence formation, days to inflorescence colouring, days to pollination, days to milky stage and days to physiological maturity) were evaluated. The results of analysis of variance indicated that evaluated genotypes hadsignificant differences for six traits of twelve measured traits. Correlation coefficient analysis indicated that the highest positive significant correlation was observed between the days to flowering and days to panicule colour change. The result of Euclidean distance matrix showed that QA1 with QP1 and QA1, QA2 and QP1 with each other, had the least genetic distance, the highest genetic distance was observed between QA1 and QP3. The results of principal component analysis (PCA) characterized three components that these justified 96.6% of the data variation. The first component justified (Yield) 45.5%, the second component (Germination) 40.4% and the third component (Height) 10.7% of the total diversity of the data. Based on cluster analysis, thousand grain weight and day to milky stage were identified as the most important factors affecting the choice of quinoa genotypes to improve early-maturity genotypes with greater yield. The results of principal component analysis showed that QA1, QA2 and QP1 selected for seed breeding programs and also QP2 based on its important growth traits, were fitted as a genotype is used in forage breeding programs.

Since medicinal plants in natural areas spread within the broad geographic limitations and collection and access to them is not cost-effective and on other hand, the use of natural habitats will not be enough for the pharmacy industry, therefore, it is necessary to grow these plants in agricultural areas. In this regard, the choice of the landraces and suitable cultivars and nutrition and irrigation management, play an important role in increasing the quantity and quality of medicinal plants and reduce the negative effects of various environmental stresses on plants. The present research aimed to study the effect of drought stress on some physiological and quality traits of calendula varieties under use and non use of vermicompost. In order to investigate of the effect of vermicompost levels on some of physiological and qualitative traits of different varieties of calendula (Calendula officinalis L.) under different drought stress levels, a pot experiment was conducted as split factorial based on a randomized complete block design with four replications in Torbat- Heydariyeh during 2012-2013. Treatments included vermicompost in two levels (0 and 50 valium percentage; the half volume of pot was soil and half volume, vermicompost) and drought stress in three levels (100, 50 and 20 percentage of field capacity) in main plots and seven varieties (low petals and many petals of Tehran and Esfahan as Iranian varieties and Faron, Golden yellow و Dandy as Netherland varieties) in sub plots. For applying water stress, after determining field capacity of soil, water loss per day was provided by weight method. Meatured traits included total dry weight, flower, leaf, stem and root dry weight, essential oil percentage and flower’s extract. The result indicated that with vermicompost applying, total physiological traits and essential oil percentage of calendula were increased. With increasing in drought stress to 25 percentage of field capacity, stem, root, leaf and flower dry weights decreased 36. 5, 43. 8, 37. 9, 45. 2 percentage compared to irrgation in field capacity, respectively. With increasing drought stress to 25 percentage of field capacity, essential oil percentage of calendula was decreased (39. 1%). Different varieties were different for root to shoot dry weight ratio and harvest index. The highest flower dry weight was obtained in Golden yellow variety that it had n’t significant difference with many petals of Esfahan and Tehran. The highest essential oil percentage was observed in low petals and many petals of Esfahan, many petals of Tehran and Golden yellow. The intraction effect of vermicompost, drought stress and variety was significant on total dry weight of plant, stem, flower and root to shoot dry weight, statistically. The hieghst total, leaf, stem, root and flower dry weight were observed in Foren variety under field capacity and fertilizer appling. Generally, the study results showed that the reaction of varieties to drought stress levels and nutritional condition was different, but optimum nutritional status could improve the growth and yield of calendula varieties and also adjust the effects of drought.

Recently, double-cropping of rice in Mazandaran due to favorable climate condition is highly interested by the rice farmers. So that, after harvesting of main crop of rice, farmers can grow again one crop of rice during summer, especially in the years which climate conditions are suitable for double cropping of rice in a rice-rice growing system. Therefore, development of suitable field practice and management to produce optimum level of grain yield of cultivars which released for double cropping rice system is crucial. Hence, this experiment was carried out to develop a suitable field practices, including transplanting date and nitrogen (N) application rate on Kuhsaar cultivar in a double - cropping system of rice in Mazandaran, Amol during 2012. With this experiment rice cultivar so called Kuhsaar was used and the effect of two factors studied in this experiment including: 1) transplanting date in three levels (10 days interval started from 9th August 2012), and 2) nitrogen fertilizer rates (0, 25 and 50 Kg/ha) were tested in a factorial experiment arranged in Randomized Complete Blocks Design (RCBD) with 3 replications. Results of analysis of collected data in this experiment indicated that the effect of transplanting dates was significantly different for traits such as days to 50 percent flowering, harvest index, number of filled grain/panicle, and grain yield (α < 0.05), and plant height, flag leaf area, un-filled spikelet /panicle (α < 0.01). Also, effect of nitrogen rate was significant for effective tillers/plant (α < 0.01), and interaction of transplanting date/ nitrogen rate was also significant for two traits including effective tillers/plant and harvest index. Traits mean comparison through least significant differences (LSD) method showed that 1st transplanting date (August 9th) performed a higher number of grain/ panicle (74.93), as the main component of grain yield, with a maximum grain yield (4194.7 kg/ha). We found that traits such as panicle/plant and panicle harvest index (PHI) were in maximum level in 1st and 2nd dates (19th and 29th August) of transplanting. According to the results of testing two factors of interest, including transplanting dates and nitrogen application rates we found that through transplanting of this cultivar earlier on 9th August in summer that climate factors affecting plant growth such as temperature and radiation which are in optimum condition could be suitable field practices in a rice-rice cultivation system, will produce the optimum amount of grain yield.