تاثیر سطوح مختلف دی‌اکسید‌ کربن و محلول‌پاشی اتانول بر رشد و برخی ویژگی‌های فیزیولوژیک و بیوشیمیایی ریحان

به‌منظور بررسی تاثیر سطوح مختلف دی‌اکسید کربن و محلول‌پاشی اتانول بر فرایندهای فیزیولوژیک و بیوشیمیایی ریحان رقم‌کشکنی لولو (ocimum basilicm cv. keshkeni luvelou) آزمایشی گلدانی به‌صورت فاکتوریل در قالب طرح کاملاً تصادفی با سه تکرار در گلخانه پژوهشی گروه علوم باغبانی و مهندسی فضای سبز دانشگاه فردوسی مشهد در سال 1398 اجرا شد. فاکتورهای آزمایش شامل محلول‌پاشی اتانول در 4 سطح (0، 10، 20 و 30 درصد حجمی) و دی‌اکسید کربن در 3 سطح (380، 700 و 1050 میکرومول بر مول) بودند. نتایج این پژوهش نشان داد که بیش‌ترین محتوای نسبی آب برگ، فتوسنتز، تعرق، هدایت روزنه‌ای و پروتئین برگ در تیمار محلول‌پاشی 20 درصد حجمی اتانول همراه با کاربرد 700 میکرومول بر مول دی‌اکسید کربن بود که به‌ترتیب 45، 295، 684، 83 و 328 درصد افزایش نسبت به تیمار شاهد داشت. جرم زیست‌توده تازه و خشک شاخساره با افزایش غلظت دی‌اکسید کربن و محلول‌پاشی اتانول افزایش معنی‌داری پیدا کردند. به‌طوری‏که بیش‌ترین مقدار آن‌ها در محلول‌پاشی 30 درصد حجمی اتانول همراه با کاربرد 700 میکرومول بر مول دی‌اکسید کربن به‌دست آمد که به‌ترتیب 176 و 76 درصد نسبت به تیمار شاهد افزایش داشت.بیش‌ترین فعالیت آنزیم‌های پلی‌فنل اکسیداز، گایاکول پراکسیداز و مقاومت روزنه‌ای و نشت الکترولیت مربوط به محلول‌پاشی 30 درصد حجمی اتانول همراه با کاربرد 1050 میکرومول بر مول دی‌اکسید کربن بود که به‌ترتیب 2، 4، 65 و 76 درصد نسبت به تیمار شاهد افزایش نشان داد. در کل نتایج این پژوهش نشان داد محلول‌پاشی 20 و 30 درصد حجمی اتانول همراه با کاربرد 700 میکرومول بر مول دی‌اکسید کربن بیش‌ترین تاثیر را در افزایش فتوسنتز و در نهایت زیست‌توده تازه و خشک گیاه ریحان داشت.

the effect of different levels of carbon dioxide and ethanol spraying on the growth, and physiological and biochemical characteristics of basil

abstract: one of the research requirements in agriculture is to find a new and practical method for sustainable production that brings the highest efficiency and the least harm to humans and the environment. in order to investigate the effect of different levels of carbon dioxide and ethanol foliar spraying on the physiological and biochemical characteristics of basil (ocimum basilicm cv. keshkeni luvelou), a factorial pot experiment based on a completely randomized design with three replications was conducted in the research greenhouse of the department of horticultural sciences and landscape of ferdowsi university mashhad in 2018. the factors included ethanol spraying at 4 levels (0, 10, 20, and 30% v/v) and carbon dioxide at 3 levels (380, 700, and 1050 µmol mol−1). the results showed that the highest relative water content (rwc) of leaf, photosynthesis rate, transpiration rate, stomatal conductance, and leaf protein were observed in the treatment of 20% v/v ethanol foliar application with the application of 700 µmol mol−1 of carbon dioxide, as they increased by 45%, 295%, 684%, 83%, and 328% compared to the control, respectively. fresh and dry biomasses of shoot parts increased significantly with increasing carbon dioxide concentration and ethanol spraying. thus, the highest fresh and dry biomasses of shoot parts were obtained in foliar spraying of 30% v/v of ethanol and 700 µmol mol−1 of carbon dioxide which increased by 176% and 76%, respectively, compared to the control. the highest activity of polyphenol oxidase and guaiacol peroxidase, stomatal resistance, and electrolyte leakage were related to spraying 30% v/v of ethanol with an application of 1050 µmol mol−1 of carbon dioxide which showed an increase of 2%, 4%, 65%, and 76%, respectively, compared to the control. overall, the results showed that foliar spraying of 20 and 30% v/v of ethanol along with the application of 700 µmol mol−1 carbon dioxide had the greatest effect in increasing photosynthesis and finally the fresh and dry biomasses of basil.background and objective: basil (ocimum basilicum l.) is one of the valuable plants that is widely cultivated in the warm regions of africa, asia, and the mediterranean climate zone. finding a practical method for sustainable production in agriculture that brings the highest efficiency and the minimum harm to humans and the environment is necessary. one of the effective methods of fertilization in the agricultural system is the foliar application of fertilizers and leaf feeding, by which nutrients can be quickly provided to the aerial parts of the plant. alcohols are passively absorbed by plant cells via simple diffusion through the membrane. in this regard and considering the positive effects of ethanol, this research aims to investigate some physiological and biochemical responses of basil cv. keshkeni luvelou to carbon dioxide and foliar application of ethanol.methods: a pot experiment was conducted as a factorial experiment based on a completely randomized design with three replications in the research greenhouse of the department of horticultural science, faculty of agriculture, ferdowsi university of mashhad in 2018. experimental factors included ethanol foliar application at 4 levels (0, 10, 20, and 30% v/v) and carbon dioxide at 3 levels (380, 700, and 1050 µmol mol−1). the plants were harvested at the flowering stage to evaluate some physiological and biochemical characteristics including photosynthesis rate, transpiration rate, stomatal conductance, leaf relative water content (rwc), leaf protein, electrolyte leakage, polyphenol oxidase activity, guaiacol peroxidase activity, and stomatal resistance. minitab17 software was used to analyze the data and the mean comparison was performed based on the bonferroni test (p < 0.05).results: the results showed that the highest leaf rwc, photosynthesis rate, transpiration rate, stomatal conductance, and leaf protein were observed in the treatment of 20% v/v ethanol foliar application with the application of 700 µmol mol−1 of carbon dioxide. in addition, the highest polyphenol oxidase and guaiacol peroxidase activities, stomatal resistance, and electrolyte leakage were obtained in the treatment of 30% v/v ethanol application with a 1050 µmol mol−1 of carbon dioxide. the fresh and dry biomasses of shoot increased significantly with increasing carbon dioxide concentration and ethanol spraying. thus, the highest fresh and dry biomasses of shoot were obtained in the foliar spraying of 30% v/v ethanol with the use of 700 µmol mol−1 carbon dioxide.conclusions: in this study, the results showed that all the studied traits were affected by ethanol foliar spraying and elevated carbon dioxide. furthermore, the results showed that foliar application of 20 and 30% v/v of ethanol with the application of 700 µmol mol−1 of carbon dioxide had the most effect on the studied characteristics. besides, the control treatment (without ethanol foliar application and carbon dioxide injection) had the least significant effect on the studied traits. overall, the results of this research showed that foliar spraying of 20 and 30% v/v of ethanol with the application of 700 µmol mol−1 carbon dioxide had the greatest effect in increasing photosynthesis rate and the fresh and dry biomass of basil plants.references:1. khosravi, m.t., mehrafarin, a., naqdi badi, h.a., haji aghaei, r., khosravi, a., 2011. the effect of methanol and ethanol on the performance of echinacea purpura in karaj. j. med. plant res. 2(2), 128–121.