مجله علوم گیاهان زراعی ایران
سال پنجاهم شماره 4 (زمستان 1398)

To evaluate the amount of yield changes, some yield components and weeds control under the presence or absence of airborne dust, an experiment was conducted in the research field of the University of Kurdistan, (Dehgolan) in 2017. The experimental design was a randomized complete block in which treatments were arranged as split-plot with four replications. The experimental treatments include the levels of the airborne dust application (the existence of airborne dust and non-existence of airborne dust as the control) and also application of various herbicides included mesosulfuron-methyl + iodosulfuron (Atlantis OD), 2,4-D + MCPA, clodinafop propargyl, weedy control, and hand weeding control, which all can be considered as the main factor. The results showed that the highest dry weight of weeds, decreased yield and studied traits (6.3% decrease in height, 2.9% number of grains per spike, 4.72% the thousand seed weight and finally 10.3% decrease in grain yield) was observed due to the existence of airborne of dust .The most negative impact of dust on the 2,4-D herbicide (reduction of 64% herbicide efficiency) was observed, but the efficiency of mesosulfuron-methyl + iodosulfuron didn’t decrease under the effect of airborne dust. In conclusion, the highest weed dry weight loss was related to mesosulfuron-methyl + iodosulfuron treatment.

To investigate the effect of different irrigation regimes and bio-fertilizers application on morphological, physiological, yield and yield components of two millet cultivars, an experiment was conducted as split factorial based on complete randomized blocks design with four replications on the research farm of Fereydunshahr, Esfahan province in 2016. In this experiment, irrigation regimes were considered as the main plots with three levels (100, 75 and 50 percent of plant water requirement) while bio-fertilizer (with three levels including control, using 1 or 0.5 L.ha-1 Azotobacter chroococcum and Azospirillum brasilense as seed inoculation) and millet cultivars (including Golbaf and Bastan) were arranged as factorial sub plots. The results of varience analysis showed that plant height, days to maturity, relative water content, biological yield, number of panicles per plant, number of seeds per panicle, the thousand-seed weight, grain yield, harvest index were significantly decreased under the water deficit stress. The highest seed yield obtained in non-stressed treatments by using 1 liter of bio fertilizer while the lowest was observed under the severe deficit water stress without bio fertilizer which indicates a 63.2% reduction in seed yield due to the severe water. According to the results of this experiment, the application of bio fertilizer could reduce the harmful effects of water stress on yield and yield components in both millet varieties. Bastan cultivar showed greater biological and seed yield advantage over Golbaf cultivar under different irrigation regimes including with or without bio-fertilizers.

To study the effects of sowing date and end of season drought stress on yield and yield components of lentil, a field experiment was conducted as factorial based on a randomized complete block design with four replications in the Agricultural Research Station, Higher Educational Complex of Saravan during the growing season of 2015-2016. Experimental treatments were sowing date at three levels: November 5 and 20, and December 5, and drought stress at three levels: control (full irrigation), drought stress at flowering stage, and drought stress at podding stage. The cultivated genotype was the local mass of Sistan. Results showed that drought stress and sowing date levels had significant effects on seeds and pod per plant, 100- seed weight, grain and biological yield and harvest index. Interaction effect of drought stress and sowing date was significant on all studied traits. Full irrigation and November 5 sowing date increased all the studied traits. Moreover, drought stress during the flowering stage with delay in sowing date significantly decreased all studied traits. Due to high temperature, no yield was produced on December 5 sowing date.  The most correlation was observed between seed yield and harvest index (r= 0.89**), biological yield (r= 0.75**) and number of pods per plant (r= 0.76**). It was concluded that early sowing date (November5) and preventing drought stress during the critical stages of flowering and podding was important factors in increasing the yield of lentil in Saravan weather conditions.

The sunflower is one of the most important oily plants in the world. To study different methods of chemical fertilizer, biological and manure nutrition with foliar application of plant biostimulant on grain yield in sunflower, a factorial arrangement of treatment in a randomized complete block design with three replications was carried out in a field of Payaam Nour Arak University in Markazi province in the year of 2013. Nutrition methods [N1= 300 Kg ha-1 Urea (Control), N2= 50% of nutrition by Urea + 50% of nutrition by FAM (15-ton ha-1), N3= 50% of nutrition by FAM + 50% of nutrition by nitrogen fixation of Phaseolus sp.), N4= 50% of nutrition by Urea + 50% of nutrition by nitrogen fixation of Phaseolus sp.) and plant bio-stimulants (B1= Foliar with wermiwash, N2= Foliar with enrich wermiwash, N3= Foliar with bio ferment, N4= Foliar with effective microorganisms + quail egg) were assigned in plots. Results indicated that the effect of different levels of nutrition methods on the characteristics such as stem height, dry weight of stem and leaves, grain yield, productivity index of plant and number of grain per m-2 were significant. The Effect of plant bio-stimulants treatment on the characteristics such as stem diameter, dry weight of stem and leaves, grain yield, productivity index of plant, 1000 grain weight and the number of grain per m-2 were also significant. The maximum and minimum of grain yield (3705 and 3133 kg ha-1) were obtained with the 300 Kg ha-1 Urea (Control) and (50% of nutrition by Urea + 50% of nutrition by nitrogen fixation of Phaseolus sp.) treatments, respectively. In the biostimulant treatment, the most and least amount of grain yield with an average of 3744 and 3031 Kg ha-1, were spray of effective microorganisms and enriched vermiwash, respectively.

 In a sustainable agricultural system, the utilization of organic matters such as humic acid had the minimum damage to the environment and with its hormonal like activity; it can absorb water, mineral nutrients, and ultimately increase crop yields. To investigate the effect of humic acid on quantitative yield and some qualitative characteristics of sunflower (Var. Farrokh Hybrid) under drought stress, a split-plot experiment was conducted in a randomized complete block design with three replications at Shahroud Agricultural Research Center, Shahroud, Iran. Treatments were three levels of drought stress: control (irrigation by 100% water requirement), mild stress (irrigation by80% water requirement) and high tension (irrigation by 60% water requirement) as the main plots and five levels of humic acid: control (no humic acid), two concentrations of foliar application (1.5 and 3 gr/ liter of water), two levels of field application (15 and 30 kg/ha) as a subplots. Results showed that drought stress reduced grain yield (45.5%), 1000-seed weight (26.7%), head (23.3%) and stem diameters (25.9%), biological yield (44.6%), seed phosphorus (16.2%), and leaf chlorophyll “b” (50.7%) and carotenoids (29.8%). Foliar and soil applied humic acid had significant effects on plant height, head diameter, grain yield, biological yield, chlorophyll “a,” and P and K percentages in seeds and increased them. According to the results, it can be concluded that the application of humic acid can reduce the effects of drought stress on sunflower. At first, the application of 30 kg/h of humic acid and next, 1.5 gr humic acid /liter of water had the highest efficiency in improving the sunflower yield under water stress conditions.

To investigate the effect of different lepyrodiclis (Lepyrodiclis holosteoides Fenzl.) densities on grain yield reduction, as well as qualitative and nitrogen agronomic efficiency of rapeseed (Brassica napus L.), a factorial experiment was conducted in a randomized complete block design with three replications in Karaj, 2016-2017. Factors included nitrogen content from urea fertilizer source at four levels (0, 50, 100 and 150 kg N/h, rapeseed densities (70 and 90 plants/m2) and weed density at four levels (0, 5, 10 and 15 plants/m2). The results showed that maximum yield loss at 70 and 90 plant densities of rapeseed/m2 was 26.54 and 78.45%, respectively, with 150 and 100 kg nitrogen. The highest percentage of oil and oil yield were 77.40% and 1504 kg/ha, respectively that were obtained by 90 plants/m2of rapeseed and 150 kgN/ha and no weed. The highest N-agronomic efficiency (89.19 kg/kg) was obtained by 90 rapeseed plants/m2 and without weed presence. The highest N-partial factor productivity was 36.24 kg/kg that was observed in 90 plants/m2 rapeseed and 50 kgN/ha. The results of nitrogen interaction and lepyrodiclis density indicated that the highest N-partial factor productivity (87.23 kg/kg) was observed in the treatment of 50 kg N/ha and absence of weed.

To analyze genotype × environment interactions (GEI) on yield and seed oil content of 15 safflower genotypes (including 8 breeding lines, 6 cultivars and one landrace), multi-environment trials were conducted in three sowing times (fall, entezari and spring) at four dryland agricultural research stations including Kermanshah, Maragheh, Kurdistan and Zanjan (totally 21 environments) during 2011-2013. The two models combined index (regression analysis + yield) and GGE biplot were used for stability analysis. The combined ANOVA revealed that genotype, environment, and GEI were highly significant for the two traits (P < 0.01). The sum of squares of genotype, environment, and GEI were accounted 5, 62 and 24% for yield, and 25, 45 and 22% for oil content.The result of regression analysis indicated that the regression components were significant in both traits. According to combined index, G5, G1, and G6 for yield, and G5, G3 and G4 for oil content were superior genotypes. The polygon view of the GGE biplot showed that all test environments were divided into 3 environmental groups for both traits. Two environments of Maragheh for yield and six environments of Kurdistan for oil content were favorable. Based on GGE biplot, G10 and G5 for yield and G11, G4 and G5 for oil content had a high combination of yield (or oil content) and stability. High rank correlation coefficients were obtained between regression and GGE biplot models in both traits. Based on the results of two models, G5 (Padideh) is superior in terms of yield and oil content and is recommended for all rainfed environments.

Heat stress is one of the most important abiotic stresses reducing rapeseed productivity. In order to study the physiological responses of tolerant and susceptible rapeseed cultivars to heat stress, two tolerant, SAFI5 and MAHTAB, and two susceptible cultivars, DH13 and ZAMAN, were planted in a growth chamber in a factorial experiment based on a completely randomized design with three replications. Plants were moved to a chamber with 35/22 (day/night) temperature for 72 hours at the flowering stage. Leaf temperature, relative water content, electrolyte leakage, chlorophyll fluorescence (Fv/Fm), the content of chlorophyll a and b and carotenoid content were measured. Relative water content decreased significantly and leaf temperature increased under stress while electrolyte leakage did not change remarkably. Chlorophyll fluorescence decreased due to heat stress, susceptible cultivars showing more reduction. Content of chlorophyll a and b decreased under heat stress condition. Carotenoid content, however, increased in tolerant cultivars and decreased in susceptible ones. Significant high correlations were observed among relative water content, leaf temperature, chlorophyll fluorescence, and chlorophyll content. In sum, the results indicated that relative water content and leaf temperature had a greater contribution to heat tolerance and could be applied in screening tolerant varieties.

Chia (Salvia hispanica L.), has achieved economic importance due to the products which are obtained from its leaves with antioxidant capacity and especially its seeds, because they contain omega 3. However, there is a lack of information on optimal agronomic management practices and especially the influence of water availability on its establishment and production. To evaluate the effect of various moisture regimes on some growth and physiological parameters of the medicinal plant of chia, a greenhouse experiment conducted at the university of Agriculture and natural Resources of Tehran, based on randomized complete blocks design with three replications.The treatments incorporate moist regimes that have been applied at 66, 57 and 43 and 35% Levels of soil Field capacity. Results demonstrated that diverce moisture regimes had a meaningful influence on most pre-examined parameters. Relative water content (RWC), the total biomass of plant, plant height, accessory branch, node number and the ultimate Leaf area decreased with increasing drought stress such that the lowest value of stated parameters is obtained in the 43% soil Field capacity. Also the highest value of ELI and root weighthad been obtained through 43% soil Field capacity. The lowest value of Fo and Fv/Fm was observed and affiliated with 66% and 43% soil Field capacity, respectively. Generally, concerning the decreasing trend of growth and physiological parameters of chia in response to drought stress and intolerance in severe water stress, it seems, in the growing stage, it needs to sufficient moisture to maintain the membrane function and Photosynthetic processes.

In this research, the effects of different temperatures treatments including (25 (control), 30, 35, 40 and 50 0C) on pollen germination, pollen tube growth, and pollen morphology were investigated in vitro, and also the effect of late sowing date as heat stress on the number of pollen, also yield and yield components of 10 barley genotype was evaluated in field condition. At 50 0C this decrease was 72 and 60% for germination and length of pollen tube on average. High temperature significantly decreased pollen germination and pollen tube length in all genotypes. Genotypes showed different responses to temperature treatments, indicating different levels of tolerance among genotypes. In vitro, genotypes were divided into three groups according to the TSRI index as tolerant (Jounob, Reyhan 03, Zehak, Nosrat, Khoram), semi-sensitive (Yousef, Izeh, and Mahour) and sensitive (Abidar and Nimrooz) genotypes. Heat stress influenced pollen morphological aberrations, so that high temperature was removed the ornamentation of axin surface. Heat stress led to a decrease in the number of pollen grains per spike (90 %), yield and yield components (40%). These approaches showed that pollen performance may provide useful information to facilitate the investigation of heat-tolerant genotypes in breeding programs suitable for warm climates.

Field experiment was conducted at Rice Research Institute of Iran, Rasht in 2017 to study the efficacy of some new herbicides in controlling the weeds of rice fields in comparison to current herbicides. Treatments were included: triafamone+ethoxysulfuron (Council), flucetosulfuron (Zechor), pyrazosulfuron-ethyl 10% WG (Saathi), Pyrazosulfuron-ethyl 75% WG (Piroz) (all in recommended and two times the recommended dosage) and recommended dose of current herbicides, butachlor (Machete)+bensulfuron-methyl (Londax) and pretilachlor (Rifit)+bensulfuron) plus weedy and hand-weeded control. Results showed that new herbicides, up to two times the recommended dosage, did not have any phytotoxicity symptoms on rice while recommended dosages of common herbicides led to 5-15% phytotoxicity. The efficacy of new herbicides (flucetosulfuron and triafamone+ethoxysulfuron) in weed controlling was similar to common herbicides, while the efficacy of both pyrazosulfuron formulations was not acceptable. Overall, the results of this study showed that two new herbicides (flucetosulfuron and triafamone+ethoxysulfuron), due to high efficiency in controlling a wide range of weeds has the capacity to be replaced the current herbicides (butachlor and pretilachlor) that are going to be eliminated due to environmental concerns in future.

Drought stress is one of the major limiting factors for crop production worldwide. The purpose of this research was to evaluate the effect of drought stress on grain yield, grain yield components and evaluation of drought tolerance indices in several spring two-row barley genotypes and cultivars of cold areas. The genetic materials were evaluated in a factorial experiment based on randomized complete blocks design with three replications. The factors included thirteen rainfed spring two-row barley genotypes and cultivars from cold areas with different origins and various irrigation levels (complete irrigation and irrigation based on 60% and 80% depletion of available soil water). The results showed that with increasing the level of drought stress, grain yield and grain yield components decreased. Based on all results at both stress levels, two genotypes originated from Pakistan and Iran and Abidar cultivar and Dayton / Ranney cultivar (improved by ICARDA) were identified as drought-tolerant genotypes. Also, a genotype originated from Ethiopia and Denmark cultivar (improved by ICARDA) failed to produce an acceptable yield in normal condition irrigation but Ethiopian genotype was able to tolerate 60% depletion of available soil water stress and Denmark cultivar could tolerate 60% and 80% depletion of available soil water stress. Also, the results of principal coordinate and cluster analyses for yield, yield components traits and drought tolerance indices were in complete agreement. The best indices for recognition of the superior genotypes in terms of drought tolerance under 60% and 80% depletion of available soil water stress were GMP, MP and STI indices. Therefore, after completion tests under drought stress in real rainfed conditions in cold and drought or semi drought areas, these genotypes can be introduced in breeding programs of barley cultivars under adverse and unpredictable rainfed conditions in cold and drought or semi drought areas.

To evaluate the effect of different irrigation regime and chemical and biological fertilizers on the fatty acids content and oil yield of evening primrose, a factorial experiment based on randomized complete blocks design with three replications was conducted in the years of 2015-2016. In the main plots, three levels of irrigation regime (irrigation at 30, 40 and 50% of field capacity) and in the factorial sub-plots three levels of chemical fertilizer (no application, 50% and 100% urea + superphosphate combined application Recommended) with four levels of biofertilizers (inoculation and non- inoculation of mycorrhiza and azospirillum). The results of the analysis of variance showed a significant difference between irrigation regimes, chemical fertilizers, biological fertilizers and interaction of irrigation regimes and fertilizer in all studied traits. Drought stress, reduced oil yield per hectare, omega (3, 6, 7 and 9), ratio of total unsaturated fatty acids to saturated fatty acids and total unsaturated fatty acids. But the total saturated fatty acids and all saturated fatty acids increased. The highest levels of gamma-linolenic, linolenic, oleic and vaccinic fatty acids due to irrigation interaction at 40% agronomic capacity and combined application of urea + triple superphosphate fertilizers with 100% recommended in combination with inoculation of mycorrhiza and Azospirilum were achieved. In general, drought stress decreased the amount of unsaturated fatty acids (reduced oil quality) and oil yield, and the use of fertilizers increased the amount of unsaturated fatty acids.

Salinity is one of the most important environmental factors that severely inhibit plant growth. To improve the salinity tolerance of wheat through diallel cross, six modified genotypes (Arta, Bezvestia, Koohdasht, Moghan3, Ohadi, and Star), 15 hybrids of crossing these genotypes (Bezvestia×Koohdasht, Bezvestia×Ohadi, Bezvestia×Moghan3, Bezvestia×Arta, Bezvestia×Star, Koohdasht×Ohadi, Koohdasht×Moghan3, Koohdasht×Arta, Koohdasht×Star, Ohadi×Moghan3, Ohadi×Arta, Ohadi×Star, Moghan3×Arta, Moghan3×Star, Arta×Star) in two levels of salinity (0. 20 ds.m-1), were sown in greenhouse as a factorial experiment in a completely randomized design with three replications. The estimation of electrical conductivity of water and inlet solutions and water output from the pot had been lasted for two weeks, and followed by traits such as leaf relative water content, osmotic regulation, seed yield, 100 seed weight, seed number per spike, and activity of catalase and peroxidase enzymes were measured. The results of the experiment showed that with increasing salinity, the traits related to the yield and relative content of water of wheat bread leaf decreased significantly. The traits related to yield and relative content of leaf water in Arta and Ohadi genotypes showed the highest decrease in stress conditions than control, while the progenies obtained from the cross between these two sensitive genotypes showed a significant decrease in the traits related to yield. The rate of activity of a catalase-peroxidase enzyme in stress conditions in the crossroads caused by the confluence of Bezostaya and Kohdasht due to heterozygosity in both parents that resulted in resistance to stress conditions. Considering the superiority of heterozygosity through intelligent crossings, it can be taken measures to improve the salt tolerance of herbs.

Coriander is one of the most important medicinal plants which has been used in the pharmaceutical industry. GGE Biplot method is one of the suitable methods for analyzing data with bilateral structure. In this research, the GGE Biplot model was used to evaluate the combinability of coriander essential oil yield in Diallel cross progenies of six parental coriander genotypes including Isfahan, Hamedan, Bushehr, Mazandaran, Markazi, and Alborz in the F1 generation in different irrigation regimes and three experiments separately through randomized complete blocks design with three replications in each experiment during the growing season of 2016. The results of genetic variance analysis showed that the effect of general and specific compatibility for essential oil yield was significant, indicating the importance of additive and non-additive genetic effects for this trait. In this study, the role of non-additive gene was more conspicuous than those of additive gene in controlling the essential oil yield. Therefore, providing superior hybrids by utilizing breeding methods based on the test progeny will be effective to improve these traits. Also, the results of the Biplot graphic analysis indicated that parental genotypes of Mazandaran (P4) and Bushehr (P6) had large specific and general compatibility and can be used as suitable parents for crosses to develop high-yielding varieties in coriander.

Hyparrhenia hirta L. is a drought tolerant herbaceous species and one of the valuable genetic reserves. Poor seed production has caused some problems related to natural regeneration of this plant and micro-propagation and the production of artificial seeds through somatic embryos in this plant is necessity and especially important. A factorial experiment based on a completely randomized design with three replications was performed to consider the effect of encapsulation of somatic embryos with different concentration of sodium alginate and calcium chloride as well as different duration of ion exchange on seedling emergence percentage from encapsulated embryos. Single adult embryos derived from suspension cultures were placed in different sodium alginate concentrations of two, three and four percent. Single embryos in sodium alginate solution were injected by syringes in various calcium chloride complex at concentrations of 50, 75 and 100 mM, and were coated in different times of 20, 30, 40 and 50 minutes. The encapsulated seeds were cultured on MS 1​​/2 without any growth regulator and kept in a growth chamber at 22 °C and the period of 16/8 h (light/darkness) for two weeks and the emerged seedlings from the alginate coating were measured. The highest germination percentage and seedling emergence (60%) was obtained from 3% sodium alginate and 100 mg calcium chloride during 40 minutes of ion exchange time.