ghorbanali rassam

The purpose of this experiment was to study the trend of yield fluctuations and related traits in released wheat cultivars in Iran from 1968 to 2016.

This experiment was conducted with 16 wheat cultivars based on a Randomized Complete Block Design with three replications at Shirvan Higher Education Complex in North Khorasan during the 2018-2019 and 2019-2020 growing seasons.

The findings indicated that the Iranian cultivars released do not have significant differences in terms of the number of seeds per spike, plant height, spike length, biological yield and gluten percentage, but grain yield, harvest index, 1000-seeds weight and protein percentage have improved by 61.84, 63.54, 62.37 and 14.4%, respectively, during the last 48 years. Additionally, wheat breeding in Iran has progressed towards single-spike formation. Path analysis showed that the plant height, biological yield, number of fertile tillers/m2 and harvest index explain more than 96% of yield changes and that traits such as the harvest index and number of fertile tillers are considered the most important traits in increasing and decreasing grain yield in Iranian wheat.

According to the results of the causality analysis, it can be concluded that the selection for grain yield, based on other traits and without considering the relationships between them, may not provide accurate results. It is necessary to obtain a correct understanding of the role of the relationships between traits in breeding programs to increase selection efficiency.

Hormones are chemical messengers that regulate various physiological processes in plants. Stevia growth is affected by them, so this study investigated how gibberellic acid (GA) and kinetin (KN) affect it.  Two RCBD experiments were conducted in 2016 in Shirvan, Iran, to study gibberellic acid (GA) and kinetin (KN) hormones. First experiment included the following GA treatments: 1. control (no GA) 2. 100 ppm 3. 200 ppm 4. 300 ppm (PPM). In the second experiment, KN was included in the treatments: 1. control (no KN) 2.  20 ppm 3.  40 ppm 4. 60 ppm. At all concentrations of KN and GA, plant height, leaf number, leaf dry matter, and biomass significantly enhanced while yield index decreased. Additionally, although GA application decreased non-reducing sugars (TSSN) and total soluble sugars (TSS), KN at 40 and 60 ppm increased TSS. In contrast to KN treatments, GA treatments improved total stevia glycosides (TSGs). Furthermore, FLV was not affected by GA, but plants treated with KN 60(KN at 60) ppm had the highest FLV. All GA concentrations induced more CHL b than control. Additionally, it boosted N, P, and K, however, only KN at 40 and 60 ppm increased N and K. Overall, the positive effects of both hormones are dose-dependent; while KN treatment was ineffective in terms of TSG productivity, GA treatment was beneficial.

Introduction:

   Mint has been used both as a medicinal and aromatic plant since ancient times. Peppermint volatile oil is one of the most important essential oils and has strong antimicrobial activity. The stage at which the maximum essential oil is obtained from the plant is not necessarily the stage at which the plant has the most biomass, therefore, the appropriate time for harvesting the plant should be determined according to the maximum amount of the effective substance and the yield of dry matter. In most of the methods of producing medicinal plants, quick access to the equipment for extracting effective substances is not possible, especially at high levels, and this requires drying a large part of the plants and extracting the effective substance in subsequent times. The quality of dried medicinal plants is defined by the content of their biologically active compounds. This study was aimed to determine the best time to harvest peppermint and the effect of different drying methods on the shoots biochemical compounds.

In order to increase the yield of peppermint medicinal plant essential oil, two separate experiments were designed and conducted in Shirvan Higher Education Complex (N 26 37', E 45 57', altitude 1067 m) in 2015. The aim of first experiment was finding the best harvest time at three levels (Before flowering, at flowering 50 and 100%) and the second experiment was finding the best method for shoot drying with nine levels (Microwave radiation at 90, 180, 360, 600 and 900 watts; Oven at 40 and 60°C; Shade; and Sun), were based on a completely randomized block design (CRBD) and a completely randomized design (CRD), respectively. In the spring of 2015, tillage operations were carried out and after preparing the land, 9 plots (2 × 3 meters) were created in it. The distance between the plots was considered 1.5 m. Rizhomes of peppermint plant was obtained from Mashhad Agricultural and Natural Resources Research Center and transplanted at 20 × 30 cm intervals on May 26. Some morpholocial and biochemical traits were measured. Essential oil extraction was done by distillation method with water and essential oil components were determined by GC/Mass method.

The effect of harvesting time was significant (p≤0.01) on the plant height, number of leaves per plant, wet and dry yield of peppermint plant. The height of the plant after 50% flowering stage did not show any significant difference, but the other investigated traits include the number of leaves per plant, the wet and dry yield of the plant, the yield of essential oil in terms of wet and dry weight, and the inhibition of free radicals in the branches in shoots harvested at the time of full flowering had the highest amount, which showed a statistically significant difference. The yield of essential oil in terms of dry matter in the full flower stage increased 1.8 times compared to the 50% flowering stage and 4.6 times compared to the pre-flowering stage. The percentage of essential oil components was also affected by the harvest time, and the highest amount was observed in the full flowering stage (98.92 percent), include the highest amount in menthol (42.39 percent) and menthone (19.13 percent). The use of micro rays caused the shortest drying time, so that with the increase of power of micro rays, the drying time decreased and the shoots were dried in 0.16 hours at the power of 900 watts. The oven application at 60 and 40 °C were statistically ranked second and third in terms of drying speed with 10 and 14.6 hours. Sun and shade drying needed 46 and 109.6 hours to reach constant moisture, respectively. The highest amount of essential oil was obtained in the shade drying method (2.13%) and the lowest amount was observed in the microwave application at 900 and 600 watt. (0.01%). After shade drying, the highest amount of essential oil was observed in the oven method at 40 °C (2%) and in the sun drying (1.44%). According to the results of this study, it is recommended to harvest the branches at the time of full flowering and dry them using oven at 40 °C to obtain more essential oil yield of peppermint shoots.

In general, the harvesting time has a significant effect on the morphological characteristics and essential oil of the peppermint shoots. Harvesting peppermint in the full flowering stage resulted in the highest amount of essential oil and essential oil yield. The maximum height and number of leaves in the plant were obtained by harvesting at the time of full flowering, but the maximum wet and dry yield of shoots was observed at the harvest of 50% of flowering. The amount of menthol and menthone as the most important compounds of mint essential oil in the full flowering stage was higher than the other two harvesting times. Also, based on the results of this experiment, different methods of drying peppermint plant have various effects on the essential oil amount of peppermint shoots. The shortest time until drying was related to the use of microwave, oven, sun and shade, respectively, and the highest yield of essential oil was obtained in shade, oven at 40 °C, microwave at 90 watt and sun, respectively.

Both Foliar nutrients and phytohormones application have crucial roles in enhancing the yield of plants and meeting the increasing demand for food. To evaluate the effects of a foliar fertilizer and growth regulators on quality and quantity yields of saffron (Crocus sativus L.), a complete block randomized experiment was conducted on the experimental farm in Farooj in 2020-2021. This study consisted of seven treatments: 1-Control, 2- Gibberellin (200 ppm), 3-Auxin (200 ppm), 4- foliar spraying of Fruit Set (specific fertilizer containing 8.75% N as NO3−, 4.37% Zn, and 10% B, 6%K, and 6% sea weed extract at a rate of 0.5 L/ha + gibberellin (200ppm), 5-Fruit Set foliar fertilizer (0.5 L/ha), 6- N-phenyl-phthalamic acid (200 mg/L as irrigation), and 7-N-phenyl-phthalamic acid (spraying with 200 mg/L). It was found that the Fruit Set treatment resulted in the highest flower height (10.33 cm) and the auxin treatment resulted in 46 % increase in leaf height over the control treatment. In the Fruit Set + gibberellin treatment, the highest flower weight (2790g) was achieved, and the highest number of mother corms (15 pieces) was obtained in the auxin and gibberellin treatment. It also was observed that the mother corm weight (44 grams) and diameter (14 cm) were highest in gibberellin treatment (47%), and auxin treatment produced the largest number of daughter corms (32 pieces). Fruit Set + gibberellin, Fruit Set, auxin, and gibberellin significantly increased flower weight by 93%, 67%, 78%, and 77%. The Fruit Set treatment was found to be most effective in terms of crocin levels. Overall, the results of this research showed positive effects of gibberellin on quantitative yield and auxin on the number of daughter corms. In addition, the application of the Fruit Set improved the flowering and quality characteristics of saffron.

Savory is an annual plant of the dicotyledonous genus Labiatae of the genus Satureja and the species Hortensis, Which is cultivated for extraction of essential oils and medicinal purposes. Therefore, choosing the appropriate method for drying savory is necessary to extract high-quality essential oils. The aim of this experiment was to investigate the effect of harvest time and drying methods on quantitative and qualitative traits of savory in 2017. In this experiment, the effect of harvest time and drying methods was examined. The results showed that the effect of harvest time had the highest wet and dry yield at the time after flowering and the lowest wet yield at the beginning of flowering. Among the three harvest times, the post-flowering stage had the highest essential oil and the lowest essential oil was allocated to before flowering. The percentage of free radical scavenging increased with increasing plant age. The amount of flavonoids at harvest time after flowering was higher than the beginning of flowering and full flowering. The highest amount of Savory plant essential oil was observed in the shade drying method and the lowest amount was observed for the amount of essential oil in the oven drying method at 60 and 75 ° C with zero grams of essential oil. After the drying method in the shade, the highest amount of Savory plant essential oil was obtained in the 90 watt microwave method and in the sun.

Modern agricultural systems have adverse effects on environmental aspects of production and ecosystem health. Loss of biodiversity due to monoculture is one of these adverse consequences. Biodiversity and agriculture are strongly interrelated. While biodiversity is critical for agriculture, sustainable use of biodiversity corresponds to agricultural structure and function, and thus is an indicator for farming practices. Indeed, biodiversity is considered as a vital component of sustainable agriculture from the food security, nutrition, and livelihoods viewpoints. Agricultural expansion and intensification led to biodiversity loss in agroecosystems and reduction in the types and levels of ecosystem services (ES) that people benefit from. Considering the importance of biodiversity in sustainable agricultural systems and variability of agroecosystems in Zanjan province, the goal of this study was biodiversity assessment of crop and horticultural products in this province.

Agrobiodiversity research, of Zanjan province was evaluated at the county level and it was classified to two groups; agronomy and horticulture. For this purpose necessary data for assessment of biodiversity indices, including cropping area and types of crop and horticultural species for eight county in Zanjan province were obtained from Jihad Agriculture Management of these counties, statistics and information center, statistical report of Jihad Agriculture Ministry, and interviews with experts, managers and farmers during 2016. All crude data entered to excel program and then, some biodiversity such as Shannon, Simpson, Berger-Parker, Sorenson's similarity, uniformity, total number of species and the total number of individuals in all species were calculated according to their equations. Data analysis was performed by Excel var. 2010 and Canoco softwares.

The results showed that the highest and lowest values of Shannon index were calculated in Khoramdarah (2.14) and Khodabandeh (0.87) countiesin crop products section, respectively. Also, in the garden products section, the highest and lowest amounts of this index were related to the Tarom (0.99) and Khoramdar (0.62) counties, respectively. In terms of Simpson's index, the highest amount was obtained in Khoramdar county for crop products section (0.83) and Tarom county (0.81) for horticultural products section. The Berger-Parker index had the highest value in Khodabandeh (0.80) and Khoramdarah (0.79) countiesrelated to crops and horticultural products, respectively. According to the Sorenson similarity index for crops products, the highest similarity was found between Abajrood and Abhar, also, the highest level of similarity was found between Zanjan and Mahneshan for garden section. In assessment of the biodiversity indicators with the climatic condition of the Zanjan province, it was determined that in crops products, the biodiversity affected by precipitation and relative humidity, but in the horticultural products, it was strongly influenced by the minimum temperature and relative humidity. The variability of Shannon and Simpson were related to relative humidity, minimum, maximum and average annual temperatures in crops production section, but, these indicators were more related to maximum and average annual temperatures in garden products section. The results of this study indicated that biodiversity indices for some townships were not favorable in Zanjan province.

The diagram of the analysis redundancy (RDA) showed that the most biodiversity indicators were more correlated with maximum temperature and relative humidity among crops and gardens products.These results indicated that biodiversity has decreased in many regions and it was reached to lowest value. From this viewpoint, we have to understand the ability of biodiversity to support ecosystems such as agroecosystems and sustainable agriculture ecosystem by providing numerous services. Therefore, educating and encouraging farmers to use of crops types can improve the biodiversity services for suitability of agricultural systems in Zanjan province.

We are thankful to Jihad Agriculture organization of Zanjan province, and Gorgan University of Agricultural Sciences and Natural Resources (GUASNR) for all their companions and supports.

A factorial pot experiment was conducted based on randomized complete blocks design in green house condition to investigate the effect of short-term salt stress on leaf photosynthesis and ion relations of two sugar beet cultivars (Madison and 7233-P29). Plants were exposed to 0, 50, 150, 250, and 350 mM salinity (NaCl and CaCl2 in 5:1 molar ratio) for 48 hours. Measurements were done on youngest fully expanded leaves. Salinity caused a significant reduction in stomatal conductance and consequently leaf net photosynthesis in both cultivars. Net photosynthesis of cv 7233-P29 at low level of salinity (50 mM) at 12 h, 24 h and 48 hours after salinity application decreased by 7.4%, 15.1% and 20%, respectively, compared to control. However, reduction in photosynthesis at highest level of salinity (350 mM) at the same times were 62.4%, 73%, and 72.3%, respectively, compared to control. For Madison the percent of reduction was significantly higher than P29. Cultivar P29 at 12 and 24 hours after salinization had significantly higher Na content than Madison up to 250 mM. Potassium concentration tended to decrease with increase in salinity. Salinity led to increased Cl- concentration in both cultivars. However, Madison had significantly higher Cl- content than P29 at the highest level of salinity at all three times of sampling. A strong correlation between photosynthesis and stomatal conductance (R2=0.98) and weak correlation between photosynthesis and sodium concentration (R2= 0.22), and photosynthesis and chloride concentration (R2=0.55) indicated that in short-term exposure to salinity, stomatal conductance was one of the main causes of photosynthesis.

Seed quality is one of the most important factors affecting seed germination and seedling growth. In order to investigate the effects of seed aging on germination and seedling growth of sunflower cultivars, a factorial experiment was conducted based on completely randomized design with three replications in seed research laboratory of Shirvan Higher Education Complex. To create 7 different treatments of seed aging, seeds of three cultivars Ghasem, Farrokh and Barzgar (as the first factor) were kept at a high temperature (43◦ C) and high relative humidity (100%) for 0 (control), 24, 48, 72, 96, 120 and 144 hours (as a second factor). The results of mean comparison showed that germination percentage, rate and seedling growth of Farrokh cultivar was more than other cultivars in each aging level. Germination percentage, rate and uniformity, seedling dry weight, radicle and stem length reduced linearly with increase in the duration aging in the all cultivars. Under the aging conditions the time to beginning and ending of germination was significantly increased. Overall, it was concluded that seed quality of sunflower cultivars was seriously decreased under the aging conditions.

Water deficit stress is the main limiting factor of crop growth and yield in arid and semi-arid environments. Hyssop (Hyssopus officinalis L.) is one of the most important medicinal plants that have numerous medical uses. In order to study the effect of drought stress on physiological and morphological traits of Hyssop، an experiment based on randomized completely design was conducted with four replications at Research Greenhouse of Agricultural College of Shirvan. Water deficit levels included 100% field capacity (control)، 75% field capacity (mild stress)، 50% field capacity (medium stress) and 25% field capacity (severe stress). Results showed that enhance water deficit (medium and severe stress) declined plant height، leaf weight، stem and shoot weight، root volume and weight. However، root dry weight to shoot weight ratio increased with increasing drought stress levels. Water deficit led increasing electrolyte leakage and decreasing relative water content (RWC). Mild stress increased chlorophyll a، chlorophyll b and total chlorophyll content، but enhance water deficit reduced chlorophyll pigments compared with control. Mechanisms of tolerant to Water deficit such as increasing soluble sugars، carotenoides and anthocyanins content were observed in plants under water deficit with increasing stress levels. In general، the experiment results showed relative tolerance of Hyssop to mild stress.

This research conducted in order to prioritize the effective criteria on development of medicinal plants cultivation in North Khorasan Province using Analytical Hierarchy Process (AHP) and Delphi methods. For this purpose, a list of effective factors offered to delphi group. Analysis of delphi process showed that among 23 offered factors 19 factors, had greater impact on development of medicinal plants cultivation. Hierarchy tree was drawn through grouping of 19 factors into four criteria including economic, promotional-educational services, cultural-social and supportive policies factors. The pair wise comparison questionnaires were then distributed among relevant researchers and experts of the province to get their opinions about the priority of criteria and sub- criteria. The questionnaires were analyzed using Expert Choice software. The result revealed that economic criterion with respective weight of 0.406 had the most impact among four criteria affecting the development of medicinal plants cultivation. The supportive policies (respective weight of 0.275), educational-extension services (respective weight of 0.193) and cultural-social factors (respective weight of 0.125) received the maximum towards the minimum priorities, respectively. The results of synthesis process showed that among the 19 factors, the guaranteed purchase and establishing of pilot fields of medicinal plants, farmers'' awareness of comparative advantage of medicinal plants, and the development of processing industries had the maximum towards minimum impacts on development of medicinal plants cultivation.

Soil macrofauna is one of the important components of soil biodiversity. This research was conducted to study the effect of climate and land use on soil macrofauna biodiversity in Northern Khorasan in 2009. The impact of climate was considered with selection two regions including Shirvan, with semi-arid climate and Jajarm, with arid-climate. In each region, two land uses including rangeland and agricultural land were considered. In sample units, the macrofauna were collected with pitfall traps, sorted and counted in terms of family. The analysis of data were perfumed using of t-test, ANOVA and PCA. The results showed that land use had significant impact on diversity in both regions. So, the taxonomic richness and Shannon diversity index were lower in rangelands compared to agricultural lands. This was attributed to low plant diversity and pressure of livestock grazing in rangelands. Also different composition of macrofauna was formed in two land uses. Impact of climate on diversity and composition of macrofauna was too much, so the favorable climate in the Shirvan compared to Jajarm region led to its improvement of soil macrofauna biodiversity.

To study the response of yield،yield components،protein and oil content of soybean cultivars to delay in planting in Shirvan region، an experiment was conducted at Research Farm of the Faculty of Agriculture، Shirvan in 2010. In this study، nine soybean cultivars (Habit، Hack، Black Hack، Cencutry، Cloumbos، Clark، Sahar، Zane and Willams) were evaluated at different sowing dates (20 May، 4 June and 20 June) in factorial experiment based on randomized complete block design with three replications. The results indicated that yield components، protein content and grain yield significantly reduced by delay planting. The first planting (20 May) had the highest grain yield (2338 kg/ha). There were significant differences between soybean cultivars for grain yield and other traits except oil content. Zane cultivar had the highest grain yield. Sahar cultivar had the lowest grain yield due to the reduced harvest index، increase days to flowering and days to poding. The results indicated that delay in planting causes reduction in grain yield. Zane، Black Hack، and Hack cultivars had the highest grain yield in all planting dates.

Drought stress in germination stage is one of most important factor that limit yield and growth of lentil in Iran. The heterotrophic seedling growth can be considered as the product of three components: initial seed weight، the fraction of seed reserves which are mobilized، and the conversion efficiency of mobilized seed reserves to seedling tissues. In order to investigate the effect of drought stress on percentage and rate of germination and seedling growth components، a factorial experiment was conducted based on randomized completely design (RCD) with three replications. The experimental factors were included three lentil cultivars (Robat، Kimia، Gachsaran) and five levels of drought stress (0، -3، -6، -9، -12 bar of polyethylene glycol 6000). The results showed that with increasing drought stress، percentage and rate of germination percentage was decreased to zero in the osmotic potential of -12 bar. Although significant difference was not observed in germination percentage in drought stress levels between different cultivars، but difference in germination rate was significant. The rank of cultivars was Robat> Gachsaran> Kimia in germination rate. The inverse linear relationship was made between drought stress levels and seedling growth components. More seed reserve depletion in Robat and Gachsaran lead to more seedling dry weight of two cultivars in compare to Kimia cultivar that had more conversion efficiency. Thus efforts to improve germination and seedling growth in lentil breeding programs should focus on improvement of component of mobilized seed reserves.