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1 - تحلیل سینوپتیکی سرمای زودرس پاییزه و دیررس بهاره در استان یزد
محمدصادق طالبیدر این تحقیق به منظور تحلیل سینوپتیک یخبندان های استان یزد، ابتدا بر اساس پایی نترین دمای روزانه 28 ایستگاه هواشناسی استان دوره 1381-1370 زمان وقوع اولین یخبندان پاییزه و آخرین یخبندان بهاره را تعیین شد. سپس بر اساس تحلیل خوش های داد ههای رقومی نقش ههای سطوح زمین و 500 أکثردر این تحقیق به منظور تحلیل سینوپتیک یخبندان های استان یزد، ابتدا بر اساس پایی نترین دمای روزانه 28 ایستگاه هواشناسی استان دوره 1381-1370 زمان وقوع اولین یخبندان پاییزه و آخرین یخبندان بهاره را تعیین شد. سپس بر اساس تحلیل خوش های داد ههای رقومی نقش ههای سطوح زمین و 500 هکتوپاسکال الگوهایسینوپتیک مسبب سرماهای زود رس پاییزه در دو گروه زبان ه های پرفشار شما لشرق و زبان ههای پرفشار شما لغربو الگوهای مسبب سرمای دیر رس بهاره در دو گروه زبانه های کم فشار جنوب شرق و زبانه های کم فشار شرقاستان یزد شناسایی شدند. تفاصيل المقالة -
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2 - Prediction of Methyl Salicylate Effects on Pomegranate Fruit Quality and Chilling Injuries using Adaptive Neuro-Fuzzy Inference System and Artificial Neural Network
M. Sayyari F. Salehi D. ValeroAdaptive neuro-fuzzy inference system (ANFIS) and genetic algorithmartificial neural network (GA-ANN) were investigated for predicting methyl salicylate (MeSA) effects on chilling injuries and quality changes of pomegranate fruits during storage. Fruits were treated wit أکثرAdaptive neuro-fuzzy inference system (ANFIS) and genetic algorithmartificial neural network (GA-ANN) were investigated for predicting methyl salicylate (MeSA) effects on chilling injuries and quality changes of pomegranate fruits during storage. Fruits were treated with MeSA at three concentrations(0, 0.01 and 0.1 mM) and stored under chilling temperature for 84 days. ANFIS and GA-ANN models were used to predict the effect of MeSA application and storage time (0, 14, 28, 42, 56, 70 and 84 days) on chilling injuries, quality parameters and physiological changes of pomegranate during storage. The GA-ANN and ANFIS were fed with 2 inputs of MeSA and time. The developed GAANN, which included 20 hidden neurons, could predict physiological changes and quality parameters of pomegranate fruit (weight loss, pH, titratable acidity, chilling injury index, ion leakage, ethylene, respiration, polyphenols, anthocyanins, total antioxidant activity) with average correlation coefficient of 0.89. The overall agreement between ANFIS predictions and experimental data was also significant (r=0.87).In addition, sensitivity analysis results showed that storage time was the most sensitive factor for prediction of MeSA effects on pomegranate fruit quality attributes during postharvest storage. تفاصيل المقالة -
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3 - بررسی تغییرات جوانهزنی بذر خردل وحشی (Sinapis arvensis) طی استراتیفیکاسیون سرد
حکیمه رحیمی بنیامین ترابی الیاس سلطانی فرشید قادری فربهمنظور بررسی تغییرات دمای کاردینال جوانهزنی بذر خردل وحشی طی رفع کمون، آزمایشی بهصورت اسپلیت پلات در قالب طرح کاملا تصادفی با سه تکرار در آزمایشگاه تحقیقات بذر دانشگاه علوم کشاورزی و منابع طبیعی گرگان در سال 1396 انجام شد. عامل اصلی، دماهای مختلف (5، 10، 15، 20، 25 أکثربهمنظور بررسی تغییرات دمای کاردینال جوانهزنی بذر خردل وحشی طی رفع کمون، آزمایشی بهصورت اسپلیت پلات در قالب طرح کاملا تصادفی با سه تکرار در آزمایشگاه تحقیقات بذر دانشگاه علوم کشاورزی و منابع طبیعی گرگان در سال 1396 انجام شد. عامل اصلی، دماهای مختلف (5، 10، 15، 20، 25 و 30 درجه سانتیگراد) و عامل فرعی دورههای مختلف سرمادهی (0، 2، 4، 6 و 8 روز در دمای 5 درجه سانتیگراد) بود. برای توصیف واکنش سرعت جوانهزنی به دما، از تابع دندان مانند استفاده شد. برای دهکهای مختلف جوانهزنی، دمای پایه از 9/2 تا 4/3 درجه سانتیگراد در بذرهای شاهد به 5/1 تا 8/1 درجه سانتیگراد در تیمار 4 روز سرمادهی کاهش یافت؛ دمای سقف در بذرهای شاهد، 25 درجه سانتیگراد بود و به 9/29 تا 9/32 درجه سانتیگراد مربوط به تیمار 6 روز سرمادهی افزایش یافت؛ با توجه به تغییرات دمای کاردینال، کمون فیزیولوژیک خردل وحشی از نوع غیر عمیق تیپ یک میباشد. بذرهای دارای کمون ابتدا در دماهای پایین بیشترین جوانهزنی داشته و با خروج از حالت کمون در دماهای بالا هم جوانه میزنند و دامنه دمایی جوانهزنی افزایش مییابد. پارامترهای تخمینی در این مطالعه میتواند در مدلهای شبیهسازی بانک بذر و برای مطالعات بعدی در مورد بیولوژی و اکولوژی خردل وحشی مفید باشد. تفاصيل المقالة -
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4 - بررسی تغییرات ترکیبات کربوهیدراتی، فنلی و فعالیت آنزیمهای آنتیاکسیدانی در حذف خواب جوانههای جانبی گردوی ایرانی (Juglans regia L.) تحت تیمارهای مختلف سرمادهی
ژیلا قلی زاده حمیدرضا صادقی پور احمد عبدل زاده خدایار همتیهدف از این پژوهش مطالعه اثر تیمار ساعات مختلف سرمادهی بر حذف خواب جوانههای جانبی گردو، متابولیسم کربوهیدراتها، محتوای ترکیبات فنلی و فعالیت پراکسیداز محلول، دیوارهای و پلیفنل اکسیداز بود. در این راستا شاخههای یکساله درختان 10 ساله روستای زیارت (از توابع شهرستان گ أکثرهدف از این پژوهش مطالعه اثر تیمار ساعات مختلف سرمادهی بر حذف خواب جوانههای جانبی گردو، متابولیسم کربوهیدراتها، محتوای ترکیبات فنلی و فعالیت پراکسیداز محلول، دیوارهای و پلیفنل اکسیداز بود. در این راستا شاخههای یکساله درختان 10 ساله روستای زیارت (از توابع شهرستان گرگان)، پس از خزان برگها بهصورت تصادفی جمعآوری و به قطعات 9 سانتیمتری حاوی یک جوانه جانبی تقسیم و در دمای 1±4 درجه سانتیگراد تحت زمانهای مختلف (0، 700، 1400 ساعت) قرار گرفتند و سپس در شرایط القایی شکوفایی جوانه (2±25 درجه سانتیگراد، فتوپریود 12 ساعت نور 12 ساعت تاریکی و شدت نور سفید فلورسانت µ mol m-2 s-120) واقع شدند. نتایج نشان داد که تیمارهای 700 و 1400 ساعت سرمادهی، درصد و سرعت حذف خواب را در جوانههای جانبی گردوی ایرانی در مقایسه با شاهد به شکل معنیداری افزایش و زمان آغاز شکوفایی را کاهش داد. همچنین سرمادهی سبب تجزیه نشاسته و قندهای غیراحیایی و افزایش قندهای احیایی شد که با افزایش درصد حذف خواب جوانه ارتباط مثبت و معنیداری داشت. محتوای فنلها، فعالیت آنزیمهای پراکسیداز محلول و دیوارهای تا 700 ساعت و فعالیت آنزیم پلیفنل اکسیداز تا 1400 ساعت سرمادهی نسبت به شاهد افزایش یافت. با توجه به نتایج بدست آمده به نظر میرسد در ساعات طولانی تر سرما دهی افزایش قندهای احیایی انرژی مورد نیاز جهت حذف خواب جوانه را تامین کرده و افزایش فنل کل و فعالیت پراکسیداز محلول و دیوارهای منجر به کاهش تنش اکسیداتیو و ایجاد تحمل سرما شد. به علاوه، افزایش فعالیت پلی فنل اکسیداز، نیز حذف فنلهای بازدارنده و ساخت فنلهای آنتیاکسیداتیو را در پی داشت که در نهایت این فرایندها به موازات هم منجر به حذف خواب در ساعات بالای سرما دهی جوانههای گردوی ایرانی شدند. تفاصيل المقالة -
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5 - A Study on the Effects of Chilling Period on Sperm Quality of Sannan and Jamunapari Goats
تی. اسواراموهان کا. نیلانی پی. سورکا پی. ماهادوان ک. بالاسوبرامانیامThe objective of the present study was to examine the effects of chilling period on semen quality of Sannan and Jamunapari. Semen of goat breeds were collected with artificial vagina and chilled at 5-9˚C. Volume, colour and pH were determined on fresh semen. After dilut أکثرThe objective of the present study was to examine the effects of chilling period on semen quality of Sannan and Jamunapari. Semen of goat breeds were collected with artificial vagina and chilled at 5-9˚C. Volume, colour and pH were determined on fresh semen. After dilution, microscopic examination was performed for the progressive motility and sperm viability. Diluted semen of both breed was compared by microscopic examination from day 0 to 3 during chilling. Hemocytometer was loaded with 10 µL of semen to evaluate the sperm count. Eosin stain (1%) was used to assess the viable sperm. Although viability and sperm velocity of both goat breed decreased(P<0.05) in a time dependent manner during chilling, the viability between the Sannan and Jamunapari did not differ significantly. However there was a significant difference for means of sperm velocity (P<0.05). Progressive motility and viability decreased gradually during chilling at 5-9˚C.In order to obtain higher successful rate of insemination, chilled goat semen should be supplied to the farmers within a day. تفاصيل المقالة -
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6 - A Study on the effect of moist-chilling and GA3 application on evening primrose (Oenothera biennis L.) seed germination
Bakhtyar Rezaee Azim Ghasemnezhad Ebrahim ZeinaliEvening primrose (Oenothera biennis L.) is native to North America, belongs to Onagraceae family, and is a biennial plant. This experiment was performed as factorial based on a completely randomized design in three replications. The main purpose of the study was to eval أکثرEvening primrose (Oenothera biennis L.) is native to North America, belongs to Onagraceae family, and is a biennial plant. This experiment was performed as factorial based on a completely randomized design in three replications. The main purpose of the study was to evaluate the effect of moist-chilling and GA3 on seed germination and flower induction of evening primrose. The seeds were soaked in distilled water for 30 min, and treated with seven levels of moist-chilling period (0,10, 20, 30, 40, 50, and 60 days) and were kept in 2-4 °C in refrigerator conditions. At the end of day 60 half of the seeds were treated with 500 ppm GA3 solution for 24 hours. After that, both groups were planted in pots with three replications to see the plant reproductive responses. Simultaneously, the same seeds were planted in Petri dishes with three replications for seed germination. Germination was controlled every three days and seed germination test was done for 15 days. Seedling characteristics were measured at the end of germination test. Results showed that moist-chilling and GA3 significantly influenced the seed germination percentage. The highest germination percentage was observed in a combination of 20 days moist-chilling conditions and 500 ppm GA3. Rootlet length increased while moist-chilling was increased from 10 to 30 days. By increasing moist-chilling to 40 - 60 days, rootlet length decreased unexpectedly. Combination of moist-chilling and GA3 did not influence flower stem production and seed yield significantly. On the other hand, the earliest flower stem production was observed in seeds treated with moist chilling for 40 and 60 days. To guaranty flower stem production of spring sowing evening primrose in the areas with warm winter, seeds are strongly recommended to be treated with moist chilling for 40 days at 4 °C. تفاصيل المقالة -
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7 - Effect of Gradual and Shock Chilling Stress on Abscisic Acid, Soluble Sugars and Antioxidant Enzymes Changes in ‘Sultana’ Grapevine.
Shima Sadat Beheshti Rooy Ghasem Hosseini Salekdeh Mehdi Ghabooli Mansour Gholami Ehsan Mohsenifard Rouhollah KarimiPlants may show different behaviours during exposure to low temperature stress through various mechanisms. In this study, the chilling responses of ‘Sultana’ grapevine were investigated during a gradual chilling (2 °C/h) and also during a shock chilling أکثرPlants may show different behaviours during exposure to low temperature stress through various mechanisms. In this study, the chilling responses of ‘Sultana’ grapevine were investigated during a gradual chilling (2 °C/h) and also during a shock chilling (5 °C/h) from 24 °C to 4 °C.After artificial chilling stress, electrolyte leakage, lipid peroxidation, hydrogen peroxide production and antioxidant enzymes activities were measured in all plants leaves. Moreover, the potential of plant to accumulate abscisic acid and osmoregulants were compared under both gradual and shock chilling stresses. Based on the results, a significant difference was found between the electrolyte leakage, lipid peroxidation and hydrogen peroxide content of plants under two chilling regimes. These indices were found to be higher in shock chilling stressed plants compared with gradual chilling stressed vines because of the lower catalase, peroxidase and ascorbate peroxidase activities. Moreover, gradual chilling stressed vines exhibited higher accumulation of abscisic acid, proline and total phenolic compounds. The chlorophyll degradation and relative water content were lower in gradual cold stressed plants. Glucose and fructose, unlike sucrose showed higher concentration in gradual cold stressed vines. Totally, under gradual chilling stress grapevine plants showed better cold acclimation by lower oxidative stress and higher accumulation of osmoregulants in compared with shock chilling stressed vines. تفاصيل المقالة -
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8 - Effects of foliar application of salicylic acid on pigments, photosynthesis, ion leakage, compatible osmolytes and antioxidant enzymes of rapeseed (Brassica napus L.) under chilling stress
Hamed Sepahvand Hamid Reza Eisvand Omid Ali AkbarpourChilling stress inhibits yield of rapeseed. Salicylic acid (SA) can improve plants’ resistance to chilling through modification of many physiological mechanisms. In the present study, foliar of SA was investigated on some physiological characteristics of rapeseed أکثرChilling stress inhibits yield of rapeseed. Salicylic acid (SA) can improve plants’ resistance to chilling through modification of many physiological mechanisms. In the present study, foliar of SA was investigated on some physiological characteristics of rapeseed under chilling stress in farm. Treatments included sowing date (conventional date, late September, and late 15-day delay, which represents chilling stress) and SA spraying including no spraying, 0, 100, 200, 300, and 400 µM. Findings revealed that conventional sowing date + 100 µM SA resulted in the maximum chlorophyll, anthocyanins, and proline contents while late sowing date+ 100 µM SA resulted in the maximum flavonoids and soluble sugar. The highest catalase activities were recorded for the plants treated with 100 and 400 µM SA, but delayed sowing + 200 µM SA led to the highest activity of superoxide dismutase. Non-application of SA + conventional date showed the highest ion leakage. Applying low concentration of SA to the rapeseed plants sown in the favorable (conventional) sowing date seems to improve their chlorophyll and anthocyanins contents, and increasing the SA in delayed sowing seems to reduce the adverse effects of chilling stress. In the case of flavonoids and soluble sugars, applying 100 µM SA in the delayed sowing group compensated for the negative effects of low temperature compared with the control, improving the plant’s resistance to this stress. In sum, the most favorable performance in most characteristics of the rapeseed was obtained with conventional sowing date along with applying 100 µM SA. تفاصيل المقالة -
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9 - Postharvest GABA Application Effects on Some Biochemical Characteristics of <i>Anthurium</i> Cut Flowers under Cold Storage Conditions
Farima Mahjoory Asghar Ebrahimzadeh Mohammad Bagher Hassanpouraghdam Mohammad Ali Aazami MavalooChilling damage under 15ºC in anthurium cut flowers reduces the vase-life, quality and marketability of the product. In the present experiment, GABA postharvest treatment (0, 1 and 5 mM) was studied on the vase-life, total soluble solid (TSS), H2O2 content, proline أکثرChilling damage under 15ºC in anthurium cut flowers reduces the vase-life, quality and marketability of the product. In the present experiment, GABA postharvest treatment (0, 1 and 5 mM) was studied on the vase-life, total soluble solid (TSS), H2O2 content, proline content, spathe browning, catalase and superoxide dismutase enzymes activity of Anthurium andraeanum 'Sirion' during 10 days of storage at 10 ºC and 5 ºC. The results revealed that 1 mM GABA treatment at 10 ºC was the treatment of choice considering the vase-life. GABA treatment had no special effect on reducing the browning incidence. GABA at 5 mM increased the SOD activity. Furthermore, GABA reduced H2O2 levels compared to control untreated flowers. Moreover, under chilling stress, proline was the highest with GABA treated flowers. One mM treated GABA treatments hold higher catalase activity. The highest TSS belonged to 5 mM GABA under 5ºC. تفاصيل المقالة -
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10 - An Economic Evaluation of Iranian Horticultural Research and Extension Policy: The Case Study of Almond Late Flowering Cultivars
Seyed Safdar Hosseini Ali ShahnavaziThis paper examines the economic effects of investment in developing and introducing Almond Late Flowering Cultivars (ALFC) in a period of 52 years from 1968 to 2020, developed in Sahand Horticultural Research Station (SHRS), using the economic surplus model and field s أکثرThis paper examines the economic effects of investment in developing and introducing Almond Late Flowering Cultivars (ALFC) in a period of 52 years from 1968 to 2020, developed in Sahand Horticultural Research Station (SHRS), using the economic surplus model and field survey data. ALFC make almond supply curve move less to the left when there is a chilling case, thus affect the economic surplus of producers and consumers. Results showed that because of ALFC, economic surplus of producers and consumers had been increased about 0.4 and 0.6 million US Dollars, respectively that the share of consumers from benefits was 58 percent. The social net present value of ALFC regarding to the cost of research and extension was about 0.1 million US Dollars. It was identified that the internal rate of return in developing and introducing of ALFC had been about 11%. The findings expressed that if the research investment in ALFC could keep the position of almond supply curve unchanged unless the weather conditions, then the economic surplus of producers and consumers would decreased 3 and 4.2 million US Dollars less annually, respectively and internal rate of return in almond research would be 33%. Comparing the results showed that the introduction of late flowering cultivars could reduce the loss only 4% per hectare. The results illustrated that investment in R& E of almond could make supply curve shift less in chilling situation because of decrease in cultivation cost, but it is necessary to enhance almond yield too. The findings identify that the efficiency of current system of R & E for almond is low. So it is a necessity to find ways for make better the R & E performance in Iran. تفاصيل المقالة -
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11 - Germination Enhancement and Primary Establishment of Three Medicinal Plants
Ghasem Esmaeili Askar Ghani Seyyed Morteza Jabbarifar Nastaran HemmatiLack of cultivation of some Apiaceae family plants caused damage and uncontrolled exploitation of pastures and severe fluctuations in these plant markets. Therefore, efforts are essential to study the domestication of these species. For germination enhancement of three أکثرLack of cultivation of some Apiaceae family plants caused damage and uncontrolled exploitation of pastures and severe fluctuations in these plant markets. Therefore, efforts are essential to study the domestication of these species. For germination enhancement of three species including Dorema aucheri Boiss., Echinophora cinerea (Boiss.) Hedge & Lamondand Ferulag oangulata (Schlescht.) Boiss., six experiments in laboratory and greenhouse conditions were designed and performed during 2017-2018. At first, a completely randomized design factorial experiment with two factors (the first factor including 13 treatments consisted of stratification, soaking in GA3 or KNO3 and the second factor including stratification temperature consisted of 5, 10 and 15°C) was executed. In the second experiment, seedlings establishment was investigated in the different substrates. The results indicated that different treatments such as chilling, GA3, KNO3, and their integration had a low effect on Dorema aucheri seed germination. The effect of stratification at 4°C for 45 days on Echinophora cinerea (97.8%) and at 15°C for 45 days on Ferulago angulata (97.8%) was so clear on germination factors. The use of different growth media showed that studied species require relatively light medium and moisture during and after germination. Accordingly, mixed soil and cocopeat with 1:1 was the best substrate. It should be noted that the suitable medium for the primary growth of seeds was very similar to their natural habitats. تفاصيل المقالة -
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12 - Investigation of Chilling Effects on Characteristics of Seed Germination, Vigor and Seedling Growth of Nepeta spp. Species
Marzieh Asgari Mohsen Nasiri Ali Ashrafe Jafari Leila Flah HoseiniTo study the effects of chilling on dormancy breaking and the increased germination characteristics of Nepeta (germination percent and speed, seedling length, vigor index, wet and dry weight), a factorial experiment in a completely randomized design with 4 replications أکثرTo study the effects of chilling on dormancy breaking and the increased germination characteristics of Nepeta (germination percent and speed, seedling length, vigor index, wet and dry weight), a factorial experiment in a completely randomized design with 4 replications was implemented in a laboratory in 2014. Factor A was the chilling treatment in three levels (control, one-month and two-month pre-chilling of wet seeds at 4°C) and factor B was related to the seeds of 10 different species of genus Nepeta. After chilling, seeds of control were placed in a germinator for 15 days at 20°C and light-to-dark cycle of 16 hours light (1000 lux) to 8 hours dark. The results showed that chilling treatments had significant effects (p<0.01) on germination percent, germination speed, vigor index and fresh weight, but they had no effects on the seedling length. The chilling effects on germination percent showed that one-month chilling had a positive effect on N. haussknechtii with 40% and N. menthoides with 36.5% and two-month chilling had a positive effect on N. haussknechtii with 43%. The two-month chilling effect on germination speed was positive for most species. Generally, one-month chilling had positive effects on the increased seed vigor index of N. betonicifolia, N. haussknechtii and N. menthoidesand by 20.48%, 25.33% and 17.99%, respectively as compared to that of control treatment and two-month chilling had positive effects on the increased fresh weight of N. cataria, N. haussknechtii , N. pungens, N. menthoides andN. crassifolia. تفاصيل المقالة -
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13 - The Effect of Gibberellic Acid and Chilling Stratification on Seed Germination of Eastern Black Walnut (Juglans nigra L.)
P. Parvin M. Khezri I. Tavasolian H. HosseiniEastern black walnut (Juglans nigra L.) is used as a rootstock for the Persian walnut (Juglans regia L.) in some parts of the world and also has an important role in forestry and wood industry. Due to the deep physiological dormancy, the seed often shows an inconsistent أکثرEastern black walnut (Juglans nigra L.) is used as a rootstock for the Persian walnut (Juglans regia L.) in some parts of the world and also has an important role in forestry and wood industry. Due to the deep physiological dormancy, the seed often shows an inconsistent or low germination percentage, making establishment difficult. This experiment was carried out as a completely randomized design with eight treatments and 16 replicates in a controlled greenhouse. The objective of this study was to determine the best treatment of breaking dormancy. Treatment groups consisted of seed priming with GA3 (400 and 800 ppm) solution for 24 hours, chilling stratification (one month and two months) and the combined treatments of chilling stratification and GA3. Results showed that the germination rate for separate application of both concentrations of GA3 and one month chilling treatment was zero, as no seeds germinated. The highest percentage of seed germination (69.27 %) was recorded with the combined treatment of two months chilling and GA3 (400 ppm). Also, this treatment showed significant differences for morphological, physiological and biochemical parameters compared to other treatments. It was found that the application of the combined treatment of chilling stratification and GA3 was effective in increasing seed germination percentage and rate as well as improving growth parameters of Eastern black walnut seedlings. تفاصيل المقالة -
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14 - بررسی تأثیر تنش سرما بر میزان فعالیت آنریم های مالون دیآلدئید، پراکسیداز و کاتالاز در چند گونه آویشن
میلاد مشوق سعدالله هوشمند محمد ربیعیتنش سرما یک تنش غیر زیستی مشتمل بر تحرکات هواشناختی است که در دمای پایین اتفاق میافتد. تنش سرما در مناطق گرمسیری و نیمه گرمسیری به عنوان مهمترین عامل محدود کننده گیاهان معرفی شده است. در بررسی فعالیت های آنتی اکسیدانی آنزیم های کاتالاز ،مالون دی آلدئید و پراکسیداز تحت أکثرتنش سرما یک تنش غیر زیستی مشتمل بر تحرکات هواشناختی است که در دمای پایین اتفاق میافتد. تنش سرما در مناطق گرمسیری و نیمه گرمسیری به عنوان مهمترین عامل محدود کننده گیاهان معرفی شده است. در بررسی فعالیت های آنتی اکسیدانی آنزیم های کاتالاز ،مالون دی آلدئید و پراکسیداز تحت تیمارهای دمایی 20 درجه سانتیگراد (شاهد)، صفر درجه و 5- درجه سانتیگراد در 3 گونه آویشن Thymus vulgaris, Thymus daensis وThymus kotschyanus که مورد بررسی قرار گرفت، نتایج نشان داد؛ در بین ارقام آویشن مورد مطالعه تنوع قابل توجهی از نظر نحوهی پاسخ به تنش های دمایی وجود دارد و میزان تغییرات آنزیم در هر 3 دما بسیار توجیه کننده نقش حفاظت کننده آنها در مقابل تغییرات محیطی میباشد. تنها در میزان فعالیت آنزیم کاتالاز، برهمکنش ارقام با دماهای تحت تیمار مخصوصا دمای 20درجه سانتیگراد (شاهد) و صفر درجه معنیدار نبود که نشان دهندهی برابری نحوهی واکنش ارقام آویشن به دو دمای تحت تیمار میباشد. تفاصيل المقالة