نشریه تولیدات گیاهی
سال چهل و سوم شماره 1 (بهار 1399)

Weeds are one of the most important factors that affect and reduce the yield of crops. Hedge parsley produces two shapes of seeds, fluffy and non-fluffy, of their germination behavior little information is available. The aim of this study was to investigate the effect of seed position, burial depth, thermal shock and seed polymorphism on germination percentage of hedge parsley.

The experiments were conducted based on factorial experiment in completely randomized design (CRD) with three replications at campus of agriculture and natural resources during years 2016-2017. In the first experiment, the factors included seed position (high, middle and low plants), temperature (20 and 25 C°) and seed shape (fluffy and non-fluffy). In the second experiment, the factors were thermal shock (100, 150 and 200 C°), burial depth (0, 2 and 4 cm) and seed shape (fluffy and non-fluffy).

In the first experiment, with increasing temperature from 20 to 25 C° germination percentage decreased and at 20 C° the highest germination percentage (73.33%) was observed. Seed shape also affected seed germination percentages. In the second experiment, the burial depth had a positive effect on seed germination and with increasing burial depth, seed germination percentage increased. Interaction of thermal shock and burial depth showed that increasing burial depth and temperature increased the percentage of germination (57.14%). In both shapes of seeds, germination percentage increased with increasing burial depth and the highest germination percentage was observed in the maximum burial depth (4 cm).

The results of this study showed that this weed is capable of germination in a wide range of environmental conditions. Germination percentage of hedge parsley increased with increasing burial depth. The optimum temperature for seed germination of hedge parsley is 20 C°. Seed shape was affected on seed germination percentage of hedge parsley.

Currently, there is an immense attention towared medicinal plant and secondary motabiltes. Yarrow (Achillea millefolium L.) is a medicinal plant which consists of two important compounds; including penene and linalool. Since these two compounds have the importance values, the researchers significantly focused on them. The rate of transcript expression of penene synthesis and Linalol synthesis induced at the end of 2-c-methyl-D-erythritol-4-phosphate (MEP) pathway that caused to produce Penene and Linalol.  In order to evaluate the synthesis of Penene and Linalol, a research study was carried to exame the exogenous treatment (zero, 25 and 50 mg/l) of gibberellic acid (GA3) at different times (24, 48 and 74 hr.) on Yarrow at the greenhouse on 1395-1397. The results of R-PCR indicated that significant rate of the transcript expression was related to the Penene synthesis at 25 mg concentration of GA3 at the 48 hr after treatment. In the most samples as the rate of the Penene synthesis increased the rate of Linalol synthesis decreased. The evidences suggested that the exogenous treatment of GA3 induced a transduction signal in the plant. In which at the end, the plant molecular process respond to it and showed in overall that evaluation of GA3 implemented different encoding gene expression for theses compounds, and illustrated that when the Penene synthesis inceased in the treated plant the Linalol synthesis dcreased simontenously.

A greenhouse pot trial was conducted at the Experimental Research Station of College of Agriculture at Shahid Chamran University of Ahvaz. The plants used in this study were provided from the National Center for Genetic and Biological Resources of Iran, with access code P1000093. Two months after seed germination, the desired amounts of gibberellic acid were prepared with distilled water (25 mg/l and 50 mg/l), and then each potted plant was sprayed uniformly with 10cc of prepared solution. Sampling was carried out by collecting the leaves of treated plants at 24, 48 and 72 hours after the treatment. The phenol-chloroform method (Wang and Ghabrial, 2002) was conducted with some modifications to extract RNA of collected leaves at the two biological replications. Quantity and quality of extracted RNAs were measured using Nanodrop and electrophoresis of %1 agarose gel. Synthesis of cDNA was performed using the Takara cDNA synthetase kit according to its manufacturer's instructions. Partial sequences of pinene synthase and linalool synthase genes were obtained in an early experiment in our laboratory (data is not published). The coding sequence of the target genes in other plants within the same family aligned with our obtained sequences to identify conserved segments for each gene using CLUSTAL W program. The standard housekeeping actin for yarrow with accession number JX679606.1, which is available in the public GenBank database, used to normalize the expression of the genes of interest. The primers of all genes (pinene synthase, linalool synthase and actin) were designed from the conserved sequences by PrimerQuest Tool, and then verified with oligoanalyzer v.3.1. Relative expressions of target genes were determined using real-time PCR with SYBR green fluorescence detection. Relative differences in target gene expression were calculated using REST software.

The acquired result of real-time PCR revealed that in pinene synthase gene, the highest amount of transcription occurred at 48 hours after the treatment with the concentration of 25 mg of gibberellic acid and, interestingly, the lowest expression of the transcript for linalool synthase gene observed at the same level of concentration and time. In most of the samples, with the increase in pinene synthase transcriptase, the amount of linalool synthase transcript decreased.

Taking into account the fact that both pinene and linalool are synthesized from the common substrate geranyl diphosphate. Therefore, an increase in the expression one leads to reduction in the transcript expression of the other one in the same pathway. Our results also confirmed that the transcription level of pinene synthase gene has been increasingly altered in response to the applied concentrations of exogenous gibberellic acid, resulting in a reduction in the expression of linalool synthase gene. Evidence suggests that the application of gibberellic acid triggers a cascade of molecular events which ultimately constitutes the plant response to the elicitor.

Horseradish has a male sterility that produces a small amount of seed with a low germination. It then propagates with root cuttings, which is also subject to a limited number of mother rootstocks. Therefore, the mass proliferation of this plant is important through tissue culture, especially somatic embryogenesis protocols. Somatic embryogenesis is a method to develop embryo via plant somatic cells during in vitro culture. The purpose of the present experiment is to find the best method for callus and somatic embryogenesis inducing horseradish, which is carried out in two B5 and NL media in both solid and liquid phases.
 

This research was carry out in the tissue culture lab of the department of horticultural sciences at gorgan university agricultural sciences and natural resources from 2016 to 2019. Calli are developed on callus induction media (B5 + 1 µM 2,4-D + 2 µM kin, NL + 1 µM IAA + 2 µM kin), and then transferred to somatic embryo induction phase (B5 + 3 µM 2,4-D + 4 µM kin, NL + 3 µM IAA + 4 µM kin) for 8 weeks. Elimination of IAA, 2,4-D and kin from induced calli done onto realization phase, and globular, heart and torpedo embryos observed 4 weeks later.
 

Based on the results, the best surface sterilization was achieved by 70% ethanol for 30 seconds and 70% aqueous sodium hypochlorite (v/v) for 60 minutes. The callus and somatic embryo were observed in both solid and liquid B5 and NL media. In the study of callus induction, according to the measurement of appearance quality and the process of callus formation, the growth and increase of callus in solid phase are higher than that of liquid phase. The highest callus induction record is seen in solid B5 medium containing 2 µM Kin and 1 µM 2,4-D. Generally, calli on embryo induction phase are bright green to yellowish and compact consisting of separate clusters of somatic embryonic cells. The results of somatic embryogenesis revealed that globular, heart, torpedo and total embryos in B5 containing 1 µM 2,4-D are more than NL containing 1 µM IAA.

Optimizing the growth of somatic embryos is important for mass propagation of plants that face problems in seed germination or have a long growth period. Due to the success of the production of horseradish somatic embryos, the results of this experiment can provide the possibility of production and propagation of horseradish plants in a short time. Further studies are required to determine the somaclonal variation of horseradish mature somatic embryos and plantlets.

Apple has a long-term supply throughout the year because of its high storage capacity. Sometimes keeping this fruit in the cold storage room for a long time reduces the quality and marketability, thus making it unattractive for consumers. Recently, there has been an increasing interest in the use of natural compounds to maintain fruit quality and extend its shelf life. Salicylic acid (SA), a widely distributed compound in plants, belongs to a group of phenolic compounds. It could be considered an endogenous plant growth regulator involved in the regulation of physiological processes and disease resistance mechanisms.

To solve this problem, the effect of different concentrations of salicylic acid on the storage of golden and red delicious apple fruits was examined at harvest, 45, 90, 135 and 180 days after storage. Treatments included no washing, distilled water, and salicylic acid 1, 2, and 3 mM for half and 1 hours in cold storage room at 1 ± 2° C. At the end of each storage period, traits such as fruit firmness, vitamin C, TSS/TA, phenol, mealy fruit, flavor (panel test), chilling index and antioxidant capacity were evaluated in three storage periods (0, 90 and 180 days after storage). A factorial experiment based on a completely randomized design was conducted. In both cultivars, harvest index coincided with 170 days after full bloom.

Results showed that chilling injury, mealy and fruit ripening reduced by salicylic acid treatment and flavor maintained. Antioxidant capacity and phenol content increased by salicylic acid treatment during the storage, but no effect on vitamin C and fruit firmness was observed. During storage, maximum of chilling injury and flavor was related to yellow apple fruit and the maximum of tissue and skin firmness, vitamin C and antioxidant activity belonged to red apple cultivar. The use of 2 mM salicylic acid for half an hour was more effective than other treatments in preserving the quality and storage of fruit of both cultivars.

The results of this study showed that at the end of the storage period the amount of mealy fruit and flavor increased, while skin and tissue firmness decreased significantly. The effects of salicylic acid include a decrease in mealy fruit and chilling injury, as well as an increase in phenolic compounds and maintenance of the antioxidant activity, flavor and TSS/TA, which ultimately increased shelf life of apple fruits. High quality and storage capacity were related to red rather than yellow apple.

Gerbera (Gerbera jamesonii L.) is one of the most important cut flowers in the world, and its production is increasing. One of the major problems in cultivating gerbera is its bent neck and short vase life. With the ever-increasing development of flowering industry and the necessity of improving the quantity and quality of flowers, it is necessary to use the beneficial elements in the production of flowers. Calcium is one of the most important nutrient elements that plays a major role in plants. It has a crucial task in the stability of cell wall and cell membrane as well as the development of cells. The balance between cations and anions, the activation of certain enzymes and the regulation of osmotic pressure are among other functions of this element. Calcium, also, plays a role in root development and prevents injuries caused by mechanical and thermal damages such as wind. Nanochelate technology has been able to significantly solve chelate problems. The present study was conducted to investigate the effects of various concentrations of calcium nanochelate on quantitative and qualitative characteristics and vase life of Gerbera.

In this study, three concentrations of calcium nano-chelate (0, 2 and 3 g/l) on three cultivars of gerbera cut flower (Intense, Amlet and Cabana) were examined. Factorial experiment was conducted in a randomized complete blocks design with three replications. In this experiment, morphological, physiological, biochemical parameters and postharvest life of these cultivars were evaluated. The related characteristics of the flower included the dry weight of the scape, the number of inflorescences per plant, the height of the flowering stem, the diameter of the scape and the diameter of the inflorescence. The percentage of electrolyte leakage or membrane stability index, chlorophyll and carotenoids content, calcium content of the plant, vase life and water absorption were investigated.

The results showed that morphological traits improved with increasing the concentration of calcium nano-chelate. Also, chlorophyll and stomatal conduction increased, but ion leakage decreased. Increasing the concentration of calcium nano-chelate increased the vase-life and water absorption in gerbera flower. The highest number of inflorescence, scape diameter, scape dry weight, inflorescence dry weight and vase life were obtained with 3 g / L of calcium nano-chelate.  

In this research, we found that gerbera treatment by calcium nano-chelate was significantly effective. Among the treatments, the concentration of 3 g/l was recognized as the best treatment by increasing the vase life and improving the growth, physiological and biochemical characteristics of gerbera cut flower.

Opium poppy (Paoaver somniferum L.) is one of the important medicinal plants considered the only source for several high-value pharmaceutically BIAs. Benzylisoquinoline alkaloieds (BIAs) are a very large and complex group of plant alkaloids. Today’s various methods of genetic engineering are applied to improve the biosynthetic pathways in medicinal plants. For successful implementation of techniques such as gene silencing and over-expression, it is important to get accurate and complete information about genetic characteristics of related genes in the biosynthesis of secondary metabolites. DBOX is one of the important genes in biosynthesis of sanguinarin and papaverin alkaloids of poppy. According to the cause, the present study was performed on DBOX to explain genetic characteristic and gene expression pattern.

Specific primers were designed based on databases, and complete sequences of DBOX gene were amplified using DNA and cDNA as a template, and then were cloned in pTZ57R/T plasmid. After sequencing of cloned fragments, CDD, CELLO and ProtParam tools were used to determine ORFs, domains and the location of protein accumulation. Phylogenetic relationship between the gene in this plant with other plants was determined. Finally, the pattern of gene expression in different tissues was assessed using real time RT-PCR technique and RNA-seq data derived from SRA data bank.

Sequencing results showed the 1614-bp fragment that has 100% identity with the DBOX gene of P. somniferum. The protein encoded by this gene was analyzed by bioinformatics methods. Three domains including FAD binding, Berberine and FAD/FMN-containing dehydrogenase in the protein sequence were identified and the existence of an N-terminal signal peptide was also determined in this protein. The results also showed that the highest concentration of protein was present in the plasma membrane and highest function of this protein was in the extracellular. In order to analyze and determine the expression pattern of DBOX gene in different tissues, 5-gene libraries of RNA-seq data of opium poppy (with ERX651037, ERX651023, ERX651056, ERX651082 and ERX651062 access numbers) derived from NCBI-SRA were analyzed. The numbers of sequences from the alignment between different tissues were compared using the Fisher exact test and Chi-squared 2X2 tests. Results of the gene expression analysis showed that the highest level of gene expression of this gene performed in roots and the lowest level of gene expression occurred in the stems. In addition, results of the real-time RT-PCR experiment were similar to in silico tests and the present results demonstrated that DBOX gene transcript levels in root were significantly more than other plant tissues.

Results showed that DBOX gene is an intron less gene. According to existing domains, this gene is a member of a FADOX gene family. Due to the presence of FAD and berberin like domains in protein sequence of this gene, its key function in biosynthesis of BIA alkaloids was confirmed. Different expression patterns of DBOX gene in root confirmed accumulation of high value sanguinarin alkaloid in this tissue.

Descurainia sophia L. is one of the most valuable medicinal plants in the pharmaceutical industry because its seeds are used for the production of mucilages. Methanol spraying, as a biological stimulant on three carbonaceous plants, can increase carbon dioxide stability and reduce respiration, resulting in more dry matter in these plants.

This experiment was carried out to investigate the effect of methanol spraying on seed yield and mucilage variation of D. sophia based on randomized complete block design with five treatments and three replications in a field experiment in Khoy, Iran. The treatments consisted of the control treatment (distilled water without methanol application) with 4 concentrations of methanol spraying (containing 10, 20, 30 and 40%) carried out during the growing season three times at intervals of 12 days (36, 48, 60 days after planting). After the last spraying at the time of full maturity, the plants in each plot were taken individually. The measured morphophysiological characteristics included plant height, plant leaf number, plant stem number, plant dry weight, number of pods per plant, number of seeds per pod, 1000 seed weight and seed yield. Also, the measured phytochemical traits included seed ash content, mucilage percentage and yield, and inflation index.

Results showed that foliar application of different concentrations of methanol had a significant effect on number of plant stems, number of plant leaves, plant dry weight, number of pods per plant, number of seeds per pod, grain yield, seed mucilage yield, seed ash, seed inflation index (p ≤ 0.01), plant height and 1000 seed weight (p ≤ 0.05). Foliar application of different concentrations of methanol had a significant effect on all morphological and functional components. To be more precise, methanol spray had a significant effect on plant height, number of stems, plant leaf number, shoot dry weight, number of pods per plant, number of seeds per pod, 1000 seed weight and seed yield, but the effect of year on none of the measured traits was meaningful. Also, the interaction between the year and methanol spraying on the traits of plant leaf number, number of seeds per pod and 1000 seed weight had a significant effect, but the remaining traits were not affected considerably. Combined analysis of variance showed that the year effect had no noticeable effect on seed ash. While methanol concentration had a significant effect (p≤ 0.01) on the seed ash content, the interaction of methanol in different years of experiment was not significant on this characteristic.

Regular methanol spraying, as an active bioavailable and a new method in the production of medicinal plants, improved seed yield and mucilage of Descurainia sophia seed. Generally, the highest values for the evaluated properties were obtained in the induction of 40% volumetric methanol solution.

Strawberry is one of the important small fruits worldwide because of its high economical value. Mazandaran is ranked second among Iran’s strawberry prodcing provinces with about 14581 tones of strawberry yearly. This research aimed to evaluate the effect of different silicon sources on the reproductive and vegetative growth of strawberry in an outdoor hydroponic system.

This experiment carried out in a factorial format with two factors consisting of growth media (double medium: 1 cocopeat + 1 perlite, and triple medium: 1 cocopeat + 1 perlite + 1 rice husk) and silicon spray (control, 50 mg/L Si from sodium silicate, 100 mg/L Si from sodium silicate, 50 mg/L Si from potassium silicate, 100 mg/L Si from potassium silicate). It was performed in Sari Agricultural Sciences and Natural Resources University at 2016. Different characteristics including silicon concentration in the leaf, aerial fresh and dry weight, leaf number, fresh and dry weight of crown, fresh and dry weight of root, yield, weight of single fruit, number of the produced fruits in each plant were evaluated.

Potassium silicate 100 increased silicon concentration of strawberry leaf significantly. Leaf number of the plant and aerial dry weight in triple medium were significantly higher than the double medium. High rate of potassium silicate in the triple medium caused lower crown diameter in comparison with potassium silicate 50 in the same medium. However, in the double medium, the potassium silicate 50 was the best treatment for crown diameter.  Both fresh and dry weight of strawberry roots were the highest in the double medium and potassium silicate 50 treatment. Single fruit weight was maximum in the double medium and potassium silicate 100, which was not significantly different from potassium silicate 100 in triple medium. Fruit dry matter in the double medium and potassium silicate 50 treatments was more than other treatments. Fruit size was affected by medium, so that fruit size in the double medium was more than the triple medium significantly.

Sodium toxicity in sodium silicate treatment, low rate of silicon in potassium silicate 50 treatment, and lack of rice husk in the double medium could all negatively affect different physiological aspects of strawberry growth; or at least, they hindered achieving positive results. In summary, it can be concluded that the double medium and potassium silicate 100 can be recommended for higher yield and big strawberry fruit, but the triple medium and potassium silicate are useful treatments for vegetative growth specially for more crown diameter and root growth.

Determination of morphological characteristics of different promising lines of rice and the effects they have on yield can be considered a good tool for identification of preferable lines with ideal agronomical traits.

In order to evaluate the most important characteristics of cultivars affecting yield in 2017, a field experiment was conducted in a research farm of Sari University of Agricultural Sciences and Natural Resources, in a randomized complete block design with three replications, in 5 square meters plots with 25×25 space between them. Morphological characteristics include plant height, panicle length and number measured before harvest in the farm, as well as other characteristics after harvest in laboratory. At the end of growth season, panicles were harvested and collected in separate bags and were selected randomly for measurement of their morphological characteristics. Mean comparisons were calculated with Duncan method in 5% level of possibility. Also, variance analysis was calculated for all the traits. Cluster analysis was calculated with ward method. The genotypes were 30 promising lines of rice. In this study, 10 traits including plant height, panicle length, panicle number, total number of grains, number of filled grains, grain length, grain diameter, grain length to width ratio, 1000 grain weight and yield were evaluated.

Correlation analysis results showed that there was a positive and significant correlation between yield and number of panicles, number of filled grains and 1000 grain weight, but the length of the grain had a negative significant correlation with yield.The results of path analysis showed that the number of filled grains had the highest direct effect (0.67), and, after that, the number of panicles (0.59) and grain width (0.47) had the highest effect on yield.Therefore, based on the results obtained from this study, number of panicles and number of filled grains as selection index on rice yield improvement were identified.The results of cluster analysis of the studied lines were also classified into four groups. The genotypes in the second and the third, in addition to the higher yields, had the lower height, number of tillers and more grain number.The average deviation of clusters from total mean was calculated for these lines and the existence of this deviation can demonstrate diversity. The genotypes in the second group add up to 57% of all the genotypes, which is above the total mean in traits including panicle number, grain length, grain diameter, 1000 grain weight and yield.

According to the results of this study, the highest lines in terms of yield and other agronomical characteristics were 8, 13, 14, 15 and 28. Also, traits including number of panicles and filled grain number can be considered selecting factors for improvement of rice yield.

Satureja avromanica Maroofi is a medicinally perennial herb which is native to Iran, exclusively restricted to Uramanat mountains of Kurdistan province. It has various pharmaceutical and biological activities such as antibacterial, antifungal, antioxidant, anti-inflammatory, antiviral, anticancer and antiprotozoal properties. The experiment was conducted to study the biochemical characteristics of S. avromanica Maroofi extract by two extraction methods as solvent and solvent-ultrasonic.

The study was carried out as a factorial based on a completely randomized design. The investigated factors were the type of solvent (water, 75% water, 50% water, 75% methanol and methanol) and extraction method (solvent and solvent-ultrasonic). For this purpose, the plant samples were collected from Uraman Mountains of Kurdistan province in July of 2016. Samples were immediately transferred to Herbarium of Agricultural Research Center and Natural Resources of Kurdistan province. The samples were dried in shade for 15 days, and then crushed into pieces of 0.5 to 1 cm by a laboratory mill (Molyneux, Spain). The content of phenol and flavonoid as well as antioxidant activity was measured. Besides, the components of phenol and flavonoid for the best treatment were determined by HPLC apparatus.

The results showed that the compounds extracted by water-ultrasonic were significantly more than those extracted by water. Inhibition percent in water-ultrasonic and water treatments were 16.62% and 11.92%, respectively. The content of phenol (45.36 mg/g, 40.29 mg/g) in water-ultrasonic was higher than that obtained in water treatment (40.29 mg/g). The flavonoid content (15.33 mg/g) in water-ultrasonic was more than that in water treatment (13.29 mg/g). Therefore, water-ultrasonic treatment was more efficient in extracting S. avromanica Maroofi compared to water treatment. On the other hand, the 75% water treatment had more compounds compared to other solvents. The chromatogram of essential ingredient revealed that S. avromanica Maroofi had more Caffeic acid, Gallic acid, Chlorogenic acid, Quercetin, p-Coumaric acid, Ferulic acid. Also, Rutin as the highest amount was obtained in Ferulic acid to be 9.12 mg/g.

We found that water is the best solvent for biochemical extraction of S. avromanica Maroofi. We found a 12% increase of phenol and 14 % increase of flavonoid in water-ultrasonic relative to water treatment. Due to the wide structure of hydrogen bonds, water is a very polar solvent with a dielectric constant at room temperature and atmospheric pressure. Ultrasonic is a type of ultrasound that increases the polarity of the liquid phase. Ultrasonic waves cause mechanical fluctuations in the liquid medium. The mechanical effect of ultrasound improves the penetration of solvent into cellular materials and mass transfer. Hence, ultrasonic waves are more efficient for producing the biochemical compounds like phenol and flavonoid.

Chrysanthemum (Chrysanthemum morifolium R.) is one of the most popular cut flowers in the world. Stem end blockage and water stress are two problems in shortening the vase life of cut Chrysanthemum. Essential oils are noble alternative substitutes for silver and chemical compounds because of their antimicrobial activities and environmentally friendly nature of the extracts. A pomegranate peel extract (PGE) was evaluated as a natural antifungal preparation for the control of postharvest rots.

This study was conducted to investigate the effect of pomegranatepeelextract of three cultivars (‘Shahvar dane sefid’, ‘Rabab dane ghermez’ and ‘Malas Poost Siah Yazdi’) in four concentration of 0, 15, 25 and 50 mg/l and Rosmarinous and Artemisia essential oils in four concentrations of 0, 25, 50 and 75 mg/l on vase life of cut chrysanthemum in a completely randomize design (CRD). Evaluated characteristics were consisted of vase life, stem end bacteria, petals water content, fresh weight loss, electrolyte leakage, protein content and peroxidase enzyme activity.

According to the results, flowers treated by 15 mg/l pomogrante peel extract of ‘Shahvar dane sefid’ showed the highest effect on vase life of chrysanthemum with 34.10% higher than control. The lowest population of bacterial in stem end of flowers was obtqined by 25 mg/l Rosmarinus essential oil with 70.14% lower than control. By increasing the extract and essential oils concentrations, bacterial population in stem end of cut flower significantly increased, while peroxidase activity significantly decreased. The lowest fresh weight loss was observed in stems treated with 75 mg/l pomegranate peel extract of ‘Shahvar dane sefid’, 15 mg/l Pomogrante Peel Extract of ‘Rabab Daneh Ghermez’, 25 mg/l Artemissia essential oil and 25 and 50 mg/l Rosmarinous essential oil. The highest petals water content (75.66%) was obtained in 75 mg/l Rosmarinus essential oil. The lowest petals water content (44.66%) was obtained in 75 mg/l Artemisia essential oil. The lowest electrolyte leakage was observed in cut stem floweres that were treated by 15 and 25 mg/l pomegranate peel extract cv.’Malas Poost Siah Yazdi’.

Generally, compared to control, all treatments were able to extend vase life and decrease fresh weight and microbial stem end of cut flowers. Also, among three pomegranate peel extracts, extracts of cv. ‘Shahvar dane sefid’ showed the highest effect on extending vase life, decreasing the fresh weight, electrolyte leakage and stem end bacteria, and thus, recommended for extending the vase life of cut flowers.

Considerng stochasticalnature of precipitation and temperature and high dependence of the eco-phenological timing traits on them, the present study was conducted with the aim of estimating eight eco-phenological traits of rainfed wheat including planting date, emergence date, flowering date, maturity date and length of each stage of growth in Golestan province.

First, studied traits were determined by daily data of maximum and minimum temperature and precipitation of 33 meteorological stations in the 26-year common statistical period (1991-2016). Then, these traits were calculated based on frequency analysis by SMADA software package for 25, 50, 75, 85 and 95 percent occurrence probability level. Planting date was determined based on the first precipitation equal to or more than 25 mm over a period of 10 consecutive days in December. Also, length of each growth stages was determined based on the concept of Growing Degree-Days (GDD). Finally, zoning maps of eco-phenological traits for different occurrence probability level were produced by ArcGIS software. In order to verify estimated eco-phenological traits values, findings from various field scale researches in Golestan province were used. The results showed that estimations and zoning maps wrere done with good precision.

The results showed that the effect of occurrence probability level was significant on all variables, so that with increasing occurrence probability level several important changes were observed: first, a significant postponement of dates of planting, emergence, flowering and maturity; second, a significant increase in the length of planting to emergence; and finally, a significant reduction in the length of the emergence to flowering, flowering to maturity and planting to maturity stages. Zoning maps showed that the suitable planting date for rainfed wheat in 90 percent of Golestan province area for occurrence probability levels of 25, 50 and 75 percent was before 10 December and for 85 and 95 percent occurrence probability levels in 78 and 90 percent of the province area was from 1-20 December and 21 December to  9 January, respectively. Emergence date of rainfed wheat in more than 90 percent of the Golestan province area for the occurrence probability levels of 25 to 95 percent was calculated until 20 December, until 4 January, 21 December to 19 January, 5 January to 3 February and 20 January to 18 February, respectively. Also, flowering date of rainfed wheat was obtained 4 April to 4 May in 95 percent of the province's area for 25 percent occurrence probability level, 5-20 May in 86 percent of the province's area for 50 percent occurrence probability level, 20 April to 20 May in 95 percent of the province's area for 75 percent occurrence probability level, 5-20 May in 75 percent of the province's area for 85 percent occurrence probability level, and 5 May to 4 June in 93 percent of the province's area for 95 percent occurrence probability level. In terms of maturity date, the results showed that this date in more than 90 percent of the Golestan province's area was 21 May to 4 June for 25 percent occurrence probability level, 21 May to 20 June for 50 percent occurrence probability level, 5-20 June for 75 percent occurrence probability level, and 5 June to 5 July for 85 and 95 percent occurrence probability levels.

Based on the average of all weather stations, the increase in occurrence probability level from 25 to 95 percent (risk reduction from 75 to 5 percent) delays the suitable planting date, dates of germination, flowering, and maturity of rainfed wheat by 37, 56, 35 and 28 days, respectively. It also increases the length of planting to germination stage by 19 days while decreases the length of germination to flowering, flowering to maturity stages, and total season by 22, 8 and 10 days, respectively.