نشریه تولیدات گیاهی
سال چهل و دوم شماره 2 (تابستان 1398)

In recent years, the desertification caused by climate change and human activity is one of the most important causes of dust particles. The occurrence of dust during the growth of crops (especially wheat) is one of the most substantial risks in crop production in western and southern regions of Iran. Thus, in these areas, an accurate estimate of dust-particle damage in crop production has great importance. Therefore, the study of the effects of dust particles on crop growth is very important. In order to study the effects of dust on grain yield and physiological and biochemical traits of wheat, a factorial experiment based on randomized complete block design with four replications was conducted at the research field, the campus of agriculture and natural resources, Razi University, Kermanshah in 2013-2014. The first factor included two bread wheat cultivars (Pishgam and Zarin) and one durum wheat cultivar (Behrang) and the second factor was applied with the aim to simulate the effect of sprinkler irrigation on the removing of dust particles on the leaf surface with two levels: washing and non-washing treatments of wheat C. With respect to the results, in the canopy non-washing treatment, Pishtaz and Behrang cultivars had the highest (6.91 ton ha-1) and the lowest (4.97 ton ha-1) grain yield respectively. The canopy washing treatment compared to the non-washing treatment significantly increased grain yield  (18% on average) and its components (without 1000 grains weight), biological yield, harvest index, and some physiological traits, including leaf photosynthesis rate, stomatal conductance, maximum efficiency of photosystem II, survival index, and some biochemical traits, such as leaf soluble proteins, chlorophyll a, chlorophyll b, and carotenoids, but it had no significant effect on transpiration rate. The lowest and the highest reduction in grain yield under air dust particles are related to Pishgam (13%) and Behrang (28%) respectively. Particles with 0.3 micrometers diameter or less  formed most of the dust particles in the air. It seems that the deposition of this size of particles in stomata pores is the main reason for stomatal plugging, and therefore, the reduction in stomatal conductance and the reduction of leaf photosynthesis rate and the decrease of grain yield reduction. Stomatal plugging by dust particles may cause less water loss and the increase in relative water content as a result. These findings suggest that, in the case of dust-particle occurrence, leaf washing with sprinkler irrigation compared with traditional irrigation method may cause significant increase in grain yield and its components and physiological and biochemical traits in wheat in this area and similar areas.

Drought is a major abiotic stress that limits agricultural crop production. Thyme (Thymus vulgaris L.) is an aromatic and medicinal plant which is very important for the herbal industry. This study was aimed to investigate the variation some of the secondary metabolites and morphological traits as well as changes in expression of genes involved in the biosynthesis of thymol (including HMGR and TPS2) by real-time PCR. One of the main goals of the present study was to find out the relationship between the transcript of these genes and related metabolites in thyme. This study was conducted in the greenhouse of Iranian Institute of Medicinal Plants of Jahad Daneshgahi (Karaj, Iran) in 2016. The experimental design was a randomized complete block design with 5 replication and 4 water deficit stress treatments, including 100% (T1, control), 70% (T2, mild stress), 40% (T3, moderate stress), and 20% (T4, severe stress) of field capacity (FC). Total RNA was extracted from leaves using TRIzol reagent following the manufacturer’s instructions. First strand synthesis of cDNA was performed immediately using 1 µg of total RNA with simultaneous use of oligo-dT (50 µM) primers and random hexamer and reverse transcriptase enzyme following the manufacturer protocol. In order to examine gene expression by real-time PCR, the method of fluorescence dye SYBR green (Fermentase, USA) was used. The amount of thymol and carvacrol were measured by HPLC. Results of morphological traits showed that increasing the water deficit stress caused a decrease in root biomass, shoot fresh weight, plant height, root length, and the number of side branches. Results of gene expression profiling showed that the highest expression of TPS2 and HMGR genes and the highest amount of thymol and carvacrol was obtained in treatment T2 (70% FC). TPS2 and HMGR gene expression changes were similar to the changes of monoterpenes thymol and carvacrol in all treatments and the highest number of monoterpenes and gene expression were obtained in mild water deficit stress treatment in comparison with control, moderate, and severe stresses. Altogether, according to the results of this study, mild stress had a significant effect on increasing the expression of HMGR and TPS2 and led to a higher production of monoterpenes.

With increasing interest for developing the cultivation of persimmon, there is not suitable technology and enough information about postharvest behavior and storability of this fruit in many of countries such as Iran. Softening, chilling injury and the incidence of different diseases are limiting factors for postharvest life of persimmons fruits during cold storage. Ultraviolet-C (UV-C) light radiation has recently suggested to controlling decay and reducing chilling injury of some fruits. Therefore, this study was conducted to evaluate the effects of UV-C treatments with different doses on alleviating chilling injuries and maintaining qualitative attributes of persimmon fruits during storage. The persimmon fruits cv. `Kashan´ were harvested from a commercial orchard near Kashan city. UV-C treatments was carried out at 0 (as control), 5 minutes irradiation from 15 and 30 cm distance with 3.2 and 0.8 kJm-2, and 10 minute irradiation from 15 and 30 cm distance with 16.4 and 4.1 kJm-2. After 1, 2, 3 and 4 months, fruits were removed from storage and chilling injury indices, polyphenol oxidase (PPO) activity and some quality attributes were measured. The effect of UV-C treatments on weight loss, chilling index, electrolyte leakage, lipid peroxidation and PPO activity was effective during storage. High percent of weight loss (6.84) and chilling symptom (40) was observed in irradiated fruits with 16.43 kJm-2 and low level of mentioned parameters was seen in 3.2 kJm-2 treatment. High level of electrolyte leakage (80.49) and lipid peroxidation (1.78 nM g-1 FW) were detected in treated fruits with 4.1 and 16.43 kJm-2 and low level of above parameters were observed in non-treated and treated fruits with 3.2 kJm-2. Application of UV-C with high dose increased PPO activity (9.7 u gr-1 FW) in comparison to other treatments during storage. Our results suggest that application of UV-C irradiation in low level after harvest could increase postharvest life of `Kashan´ persimmon by controlling chilling injuries and preserving fruit quality. However, it is worth mentioning that chilling symptoms of persimmon was reduced by low doses of UV –C irradiation. In fact, UV-C treatment with high doses caused high percentage of injured fruits. In conclusion, the use of UV-C radiation in controlling chilling injuries and maintaining quality of persimmons fruits offers an interesting research area and considering the low risk of the treatments.

Competition, as one of the key issues and complex phenomena, is in the ecophysiological discussions of plant communities and is influenced by many factors that can be attributed to weed interference with the crop and the use of fertilizer inputs. Considering that nowadays the use of plant oils and sesame cultivation has increased, the aim of this study was to investigate the response of sesame cultivars to nitrogen increase in competition with weeds to identify the limitations and benefits of nitrogen use.
 
  The experiment was conducted as a split factorial based on randomized complete block design with three replications at Omidieh (Khuzestan Province) during the summer of 2013. The main plot consisted of nitrogen fertilizer application levels (control [non-use] and use of 50 and 100 kg/ha nitrogen from urea form) and subplots were in a factorial combination of sesame varieties (Behbahan landrace, Yellow-white, tn-238, and tn-240) and weed competition in two levels (weed free and weed infest). In this experiment, morphological traits, harvest index, yield, and yield components of sesame were measured.
  The results showed that the effect of different amounts of nitrogen, weed competition, and sesame varieties on yield and yield components were significant. The interaction effects of nitrogen and sesame varieties on the leaf area index, number of capsules per plant, 1000-grain weight, and harvest index of sesame were significant. Increasing nitrogen improved LAI but weed interference reduced the number of capsules per plant by 23 percent. The effect of weed on 1000 grain weight showed that weed competition decreased this trait by 7.5 percent. The effects of nitrogen, cultivar, and weed competition on grain and biological yield were significant, so that the highest grain yield (158.06 gm-2) belonged to the 100 kg N treatment and between different varieties of sesame obtained from the Behbahan local variety(151.38 gm-2). Compared to the control (no nitrogen) the highest level of nitrogen treatment increased 31 percent in biological yield. In weed-free conditions, the Biological yield was more than the weed-infested treatment, so that the weed control increased the biological yield by 24 percent.
  The results of this study showed that the cultivation of Behbahan local variety with the application of 100 kg N, under Omidieh regional conditions, has been Improved many traits of sesame, including plant height, leaf area index, number of capsules per plant, and 1000 grain weight that this improvement was due to the get maximum yield.

Drought stress is one of the most substantial environmental stresses affecting agricultural productivity around the world and may result in considerable yield reduction. The human population is expected to increase to over 8 billion by the year 2020. Therefore, providing adequate food and preventing crop yield reduction is essential. Plant breeding can solve this problem to some extent. Evaluating yield components and their inter-relationships as well as detecting suitable selection indices are very important in the safflower breeding program. The multivariate statistical analysis can provide more insights into the deep structure of data and traits’ relationships
  In order to study the relationships between yield components of eight genotypes of safflowerunder normal irrigationand drought stress conditions and determine the high yield genotypes, a split-plot experiment was conducted in a randomized complete block design with three replications in the research field of Imam Khomeini International University, Qazvin. Irrigation regime included normal irrigation(irrigation after 60 mm evaporation from class A pan evaporation) and drought stress (watering until 50% flowering similar to normal irrigationand 50% flowering to maturity and irrigation after 100 mm evaporation from class A pan evaporation) were considered as main plots. Eight genotypes, including Kuseh Local, Sina, Isfahan Local, Mexican 88, Faraman, Soffeh, Goldasht, and Mexican 11 were used too.
  The analysis of the variance showed that the irrigation effect was significant for traits 1000 grain weight, flower weight, harvest index, and grain yield. There were significant differences among the genotypes for most of the measured traits, except boll diameter, boll number per plant, relative water content, and relative water loss. Plant height, shoot number, boll number, stem diameter, chlorophyll value, flower weight, biological yield, and harvest index positively correlated with the grain yield in both normal irrigation and drought stress conditions. Based on the results of stepwise regression and path analysis, biological yield and harvest index in both normal irrigation and drought stress conditions had the greatest effect on grain yield. Due to the high correlation between yield and harvest index and biological yield under stress conditions, the selection of varieties with high harvest index and biological yield can be very effective in achieving maximum yield under stress conditions. Factor analysis revealed that 4 factors accounted for approximately 82% variance changes in both normal irrigation and drought stress conditions. These factors were called yield, seed, boll size, and leaf water, respectively under normal irrigation, andplant vigor, yield, seed, boll size, and leaf water, respectively under drought stress conditions. Based on the seed yield factor and the biplot display, Faraman, Mahali Isfahan, Sina, and Mahali Kuseh were determined as high yield genotypes both in normal and drought stress conditions.
  Grain yield is a quantitative trait with a low broad sense heritability. Therefore, identifying the traits correlated with grain yield is a suitable strategy for the improvement and the indirect selection of grain yield. Stepwise regression and path analysis are efficient and useful statistical approaches for reaching the above aim. According to the results, the traits of the harvest index and biomass were recognized as the best suitable traits for indirect grain yield selection under normal and drought stress conditions.

Cumin (Cuminum cyminum L.) is one of the most important aromatic and medicinal plants in the world. It has a short life cycle (100-120 days) and needs little water for its growth cycle. Therefore, it is suitable for cultivation in arid and semi-arid regions of Iran. Different indices, including tolerance (TOL), mean productivity (MP), geometric mean productivity (GMP), stress tolerance index (STI), stress susceptibility index (SSI), harmonic mean (HM), yield index (YI), and yield stability index (YSI) have been employed for screening the stress tolerant genotypes. Due to the economic, medicinal, and aromatic importance of cumin, this study evaluated elite genotypes for drought tolerance in cumin in order to develop improved genetic population for farmers’ usage.
  The experiment was carried out in the research field of Shahid Bahonar University of Kerman, during the growing season of 2016-2017. In this study, 15 elite genotypes in cumin were evaluated using a randomized complete block design with three replications in two different environments, including normal and stress conditions. Stress treatment was cutting-off irrigation at the early flowering stage. Seed yield (ton/ha) was measured. Tolerance indices were calculated for genotypes based on the seed yield. To find suitable indices in order to determine the tolerant genotypes, the correlation coefficient between the calculated indices YP and YS was performed. To evaluate the relationship between the tolerance indices and the studied genotypes, principal components analysis (PCA) was performed. In order to use all tolerance indices simultaneously, an equation was used for estimating the stress tolerance score (STS).
  The results of the correlation analysis revealed that GMP, MP, and STI indices were positively correlated with seed yield under both stress and non-stress conditions. Therefore, they can be suitable indices for determining tolerant genotypes. Principal components analysis (PCA) showed that the first and second Principal component explained 61.89% and 37.52% of the total variation, respectively. According to the bi-plot graph, genotypes No. 7, 12, 8, and 13 with high MP, GMP, and STI scores and low TOL and SSI scores had the highest tolerance to drought stress. Based on the calculated STS (stress tolerance score), genotypes No. 7, 4, 12, 8, and 13 were the most tolerant genotypes and genotypes No. 14, 10, 6, 9, and 2 were the most sensitive genotypes, respectively. These results were identical with the results of bi-plot analysis. Moreover, this equation is much easier to be used than the multivariate analysis, such as principal components analysis (PCA).
  The aim of this study was the evaluation and selection of tolerant genotypes with high seed yield, and based on the results obtained from all the applied methods, it can be concluded that genotypes No. 7, 4, 12, 8, and 13 are identified as tolerant genotypes and were recommended to develop improved genetic population after being-tested in other places.

The cropping pattern will influence the crop yield due to better use of light, better crop arrangement within and between rows, and also higher access to soil nutrients (Weiss, 2000). In sesame, high water use efficiency was gained when it was planted over and even under rows rather than when it was planted as a flat form (Aggarwal, 2003). Also, biofertilizers could compensate some of the plant’s need for nutrients like nitrogen, but apparently, it’s not sufficient. So the integrated chemical and biological fertilizer will increase plant height, pod per plant, 1000 seed weight, and grain yield (Kumar et al., 2009). Therefore, the goal of this research is the evaluation of the effect of PGPR as an integrated fertilizer management and planting method on sesame yield quantity and quality.
  This study was carried out at the summer of 2016 in the experimental field station of Agricultural Faculty of Shahid Chamran University of Ahvaz. The experimental design was a split plot based on RCB with three replications. Three planting methods placed on the main plot and sub-plot, including four fertilizer management. Sesame grain yield and yield components were measured. The data were subjected to ANOVA with SPSS and Duncan test was used to distinguish the mean differences which were significant.
  Results showed that the maximum pod per plant (177 cm), biological yield (5110 kg ha-1), grain yield (1825 kg ha-1), and harvest index (35.7 %) were obtained from the alternative planting on the top row with full chemical fertilizer management. Chlorophyll index was significantly affected by the fertilizer methods. While comparing the chlorophyll index between chemical (56) and the integrated 1and 2 (44 and 48) fertilizer management, it became evident that the decline of chemical nitrogen caused a significant reduction in this index. In other words, applying a biological fertilizer or the activity of PGPRs can’t compensate for the effect of chemical N reduction. In following, reducing the chlorophyll content likely had a negative effect on the plant photosynthesis potential which caused lower 1000 grain weight in integrated treatments than the full chemical fertilizer method. In addition, the planting method had no significant effect on oil percentage, but the highest and lowest oil yield belonged to the alternative planting on the top row (710 kg ha-1) and planting under row (482 kg ha-1), respectively. Based on our data, the change in panting method had no significant effect on oil percentage, but applying chemical N had significantly increased the oil percentage. Also, planting on top of the row increased both oil percentage and grain yield, which had direct positive effects on oil yield. Both oleic and linoleic acid were increased more by PGPRs than chemical N form, but these unsaturated fatty acids were not significantly affected by the planting method treatment.
  We find that both the highest grain yield (1441 kg ha-1) and oil percentage (52.24%) belonged to the planting a row on top of row treatment. Between the integrated fertilizer management, the heights (1674 kg ha-1) and lowest (1068 kg ha-1) grain yield belonged to the full chemical fertilizer and integrated 1 treatment, respectively. In contrast, both oleic and linoleic acid were the highest at integrated fertilizer management in all planting methods with chemical treatment. We concluded that the present sesame cultivars are more adaptive to high-input systems, so we must be breeding new cultivars which are more suitable for sustainable agriculture.

Lilium is one of the most important bulbous plants produced as cut flowers and pot plants. In order to increase the quality of flowers, all plants should be fertilized correctly. Potassium is one of the elements that play a very important role in the quality and performance of ornamental flowers. Nano fertilizers increase nutrient efficiency, reduce soil toxicity, minimize the potential negative effects associated with overdosage, and are an effective step toward achieving sustainable and environmentally sustainable agriculture. The present study was undertaken to investigate the effect of potassium and nano-potassium fertilizers on the physiological and biochemical characteristics of Asiatic Lilium Hybrid cv. Tresor.
  In the current study, the effect of foliar spraying of different concentrations of potassium (0, 1, 2, and 4 mM) and nano-potassium (0, 0.5, 1, and 2 mM) was investigated on qualitative and quantitative traits of lily cut flower "Tresor" at the four stages of pre-harvest. The traits included a number of buds and leaves, bud length, bud diameter, stem length, stem diameter, length and width of leaves, fresh and dry weight of stems and leaves, flower longevity, peduncle length and diameter, dry matter percent of stems and leaves, ionic leakage, chlorophyll index and content of carotenoids, Flavonoids, anthocyanins, and chlorophyll a, b, and total.
  The result showed that there are significant differences between different spraying treatments and the number of buds, stems fresh weight, and ionic leakage. The highest stem fresh weight was observed by the 0.5mM nano-potassium, while the largest number of buds, the highest cells stability, and the lowest ionic leakage were achieved by the 4mM potassium. In regard to the traits of chlorophyll content, Carotenoid, Anthocyanin, and Flavonoid, there were no significant differences between the treatments of potassium and the nano-potassium. Also, the 4mM potassium and the 2mM nano-potassium showed the longest vase life. Considering the fact that the number of buds in the Lily is the most important trait, the 2 mM nano-potassium is recommended as the best treatment for spraying to feeding potassium. The foliar application of potassium and nano-potassium enhanced stem fresh weight and vase life of cut flower lilies and reduced ionic leakage compared to the control. Also, the largest number of buds was achieved by the 4 mM potassium. These results are in agreement with previous studies on carnation, Narcissus, and lily. Potassium is vital to many plant processes. Potassium plays a major role in the transport of water and nutrients throughout the plant in the xylem. Potassium is required for every major step of protein synthesis. Also, the enzyme responsible for the synthesis of starch (starch synthetase), which is activated by K. Briefly potassium, plays significant roles in enhancing the crop quality. High levels of available K improve the physical quality, disease resistance, and shelf life of crops.

Among the major environmental pollutants, lead is the most substantial contaminant due to causing toxicity in plants and organisms. Recently, the remediation of these metals has been considered in plants. Plant in vitro culture is a key tool in phytoremediation research. In general, Plant tissue culture and in vitro selection techniques are used to increase the tolerance and the accumulation of heavy metals which have been reported in numerous plant species and populations. The application of ornamental plants for phytoremediation in metal-contaminated soil is a new alternative. Ornamental kale is an important bedding plant in many landscapes of cold temperate regions. The present study was aimed to evaluate the Pb resistance and remediation of Brassica OleraceaVar. Acephala affected by in vitro culture as a bedding plant. This experiment was carried out in 2016 at Arak University.
  In this study, the stalk explants of Brassica OleraceaVar. Acephala was used for callus induction. Callus and plantlet were exposed to different concentrations of lead in the media. The Callus induction medium was MS (Murashige and Skoog) supplemented with 0.1 mgL-1 2,4-D and BA. The regeneration medium was MS medium supplemented with 0.5 mgL-1 NAA in combination with 1 mgL-1 BA. The rooting medium was half-strength MS medium without plant growth regulators and sucrose. All of the media containing 30 gL-1 sucrose, 7 gL-1 agar, and pH were adjusted to 5.8. All of the regeneration stages from callus induction to rooting and the acclimatization stages were done by different concentration of Pb(NO3)2 (0, 10, 25, and 50 mgL-1). The traits, such as callus browning, fresh and dry weight, callus formation, survival rate, root and shoot length, leaf number, and the lead accumulation, were evaluated during various stages of callus regeneration and rooting in plantlets. A Completely Randomized Design (CRD) arrangement with three replications was used in this experiment. Data were analyzed using the ANOVA procedure of SAS statistical software (version 9.2).
  Based on the results, not only did different concentrations of lead not have the toxic effects but also they had a stimulation effect in some concentrations on callus growth and regeneration. Lead concentrations increased leaf number and length of shoots in the regenerated ornamental kale. Lead accumulation in cultures was increased by increasing the concentration of lead in the medium at all stages of the regeneration. The highest accumulation of Pb was obtained 2395.7 ppb in callus treated by 25 mg L-1 Pb in media.
  The results of the present study showed the occurrence probability of the somaclonal variation due to 2,4-D supplemented in the media. In the regenerated plant, results revealed that the growth traits and Pb uptake were affected by Pb concentrations. Some in vitro derived plantlets showed an increase in uptake potential of lead in their organs (6.1 to 2.7 times compared to the control) and that it is remarkable and suitable for phytoremediation studies.

Persian walnut (Juglans regia L.) belongs to the family of Juglandaceae and is one of the most important nut crops in Iran. Until recently, all of the fruitful walnut trees grown in Iran are seedling originated and thus, they exhibit a significant variation, especially in nut and kernel characteristics. Therefore, the identification of the promising genotypes based on the phenotypic traits is essential in breeding programs. The aims of the current work were to evaluate 119 Persian walnut trees in different western regions of Iran based on nut and kernel characteristics, and then to detect genetic relationships among desirable genotype using ISSR marker.
  In this research, 119 Persian walnut genotypes collected from different parts of the west of Iran were evaluated based on nut characteristics. Based on the primary evaluation, 30 superior genotypes that had desirable characters in nut and kernel properties, such as nut and kernel weight, kernel percentage, kernel removal from the nut, kernel plumpness, and kernel filled were selected and then, the genetic variation among them was evaluated using 10 ISSR primers.
  The preliminary evaluation of 119 walnut genotypes illustrated that most of the evaluated genotypes showed high variability for the measured traits related to nut and kernel. Among the nut and kernel characters, the kernel shriveling showed the highest coefficient of variation (114.02%), while the lowest CV was related to the nut diameter (8.68%). Among walnut genotypes, both nut and kernel weight varied from 7-19.8 g and 2.8-9.20 g, respectively. The genetic relationship among 30 promising genotypes with ten ISSR primers indicated a considerable level of variability. All of the ISSR primers were polymorphic and produced a total of 79 alleles among the 30 genotypes, which 77 alleles were polymorphic. The size of the amplified fragments ranged from 200 bp to 1700 bp. The number of the observed alleles for each locus ranged from 3 (HB10) to 13 (UBC-807), with an average of 7.7 alleles per locus. Polymorphic index content (PIC) was observed to be highest (0.82) in the UBC-807 locus, while the HB10 locus had the lowest value (0.51) with an average of 0.75 among ISSR locus. The Jaccard’s genetic similarity coefficient ranged from 0.31 to 0.85 among the genotypes. The cluster analysis performed based on ISSR data using UPGMA, divided the genotypes into seven major groups.
  Finally, the results of this study showed that there was high variability among walnut genotypes in terms of quantitative and qualitative characteristics of the nut and the kernel. In this study, the average nut and kernel weight among walnut genotypes varied. The difference in nut and kernel properties of germplasm under the same geographical conditions may be the result of genotypic factors. The results indicated that some genotypes (16, 4, 24, 26, 11, and 17) had desirable traits in the nut and kernel. Moreover, the Persian walnut is of most important horticultural crops grown in Iran. Therefore, these genotypes can be propagated according to the vegetative methods and used for commercial cultivation or utilized for traditional breeding and advanced biotechnology studies to achieve superior progenies.