مطالعه تغییرات روزانه تبادلات گازی برگ گیاهان بادرنجبویه، نعناع گربه‌ای، ریحان مقدس و ریحان بوشهری در شهرستان اهواز

نوع مقاله : مقالات پژوهشی

نویسنده

دانشگاه شهید چمران اهواز

چکیده

چهار گیاه بادرنجبویه، نعناع گربه‌ای، ریحان مقدس و ریحان بوشهری در شرایط آب و هوایی اهواز کشت و تغییرات روزانه فتوسنتز خالص، هدایت روزنه‌ای و نرخ تعرق توسط دستگاه LCA4 اندازه‌گیری شدند. بیشترین نرخ فتوسنتز خالص بادرنجبویه، نعناع گربه‌ای و ریحان بوشهری در ساعت 9 صبح، زمانی‌که شدت جریان فتونی فتوسنتزی به ترتیب 1488، 1598 و 1645 میکرومول فتون بر متر مربع در ثانیه بود، ثبت گردید. بیشترین نرخ فتوسنتز خالص ریحان مقدس، زمانی که شدت جریان فتونی فتوسنتزی 1821 میکرومول فتون بر متر مربع در ثانیه بود، مشاهده گردید. شدت نور زیاد باعث بازدارندگی نوری در چهار گیاه گردید. نقطه اشباع گیاهان مورد مطالعه در شرایط منطقه حدود 1500میکرومول فتون بر متر مربع در ثانیه بود. روند تغییرات فتوسنتز خالص گیاهان با هدایت روزنه‌ای همبستگی مثبت و معنی‌داری داشت. همچنین هدایت روزنه‌ای همبستگی مثبت و معنی‌داری با نرخ تعرق گیاهان داشت. بیشترین کارایی مصرف آب به جز نعناع گربه‌ای که در ساعت 10 ثبت گردید، در سایر گیاهان در ساعت 9 مشاهده شد. چهار گیاه مورد مطالعه بیشترین عملکرد کوانتومی تثبیت فتوسنتز در ساعت 7 داشتند. اختلاف معنی‌داری بین چهار گیاه از نظر صفات دمای برگ، هدایت روزنه‌ای، نرخ فتوسنتز، کارایی مصرف آب و عملکرد کوانتومی فتوسنتز مشاهده شد. بادرنجبویه به دلیل هدایت روزنه‌ای بالاتر نسبت به سایر گیاهان، دمای برگ کمتری داشت. بیشترین فتوسنتز خالص، کارایی مصرف آب و عملکرد کوانتومی در ریحان مقدس مشاهده گردید. در مجموع، با توجه به صفات مذکور به نظر می‌رسد که ریحان مقدس و ریحان بوشهری بتوانند شرایط اقلیمی اهواز را تحمل نمایند.

کلیدواژه‌ها


عنوان مقاله [English]

The Study on Diurnal Changes in Leaf Gas Exchange of Lemon Balm, Catnip, Holy Basil and Sweet basil in Ahvaz

نویسنده [English]

  • Mohammad Mahmoodi Sourestani
ShahidChamran University of Ahvaz
چکیده [English]

Introduction: Mediterranean climate conditions induce several stresses that plants have to cope with, especially during summer months when high temperature and radiation levels along with low water availability in the soil prevail for long periods. Variation in physiological traits such as photosynthesis and plant water status and their association with morphological characters can play an important role in the adaptability of the species to environmental constraints. The previous studies show that scorching weather not only affects the rate of gas exchange, but also results in diurnal changes in activity. Thus, the impact of environmental stresses on plants growing in these conditions should be assessed by examining the evolution of their diurnal variations on leaf gas exchange. Aromatic plants represent a renewable source of valuable compounds that can be used in food, perfumery, and pharmaceutical industry. Among these plants, sweet basil (Ocimumbasilicum), holy basil (Ocimum sanctum), lemon balm (Melissa officinalisL.) and catnip (Nepetacataria) are very important for different industries. Studies on environmental physiology of medicinal plants are relatively scarce and very few information is available concerning the physiological basis of medicinal plant response to heat stress that is one of the most important factors limiting production of medicinal plants in Khuzestan province.
Material and methods: In order to evaluate the diurnal fluctuation of gas exchange of mentioned plants, an experiment was carried out in 2013 at research farm of Horticultural Science, Shahid Chamran University (31°20'N latitude and 48°40'E longitude and 22.5m mean sea level), Ahvaz (Iran), a site characterized by a semidry and scorching weather during late spring and summer. The experiment was arranged based on randomized complete block design (RCBD) with three replications and 4×8 factorial scheme (Four plants including lemon balm, catnip, holy basil and basil; and eight times of evaluation 7:00,9:00, 10:00, 11:00, 12:00, 13:00, 17:00 and 20:00 h). Land preparation consisted of disking and the formation of raised beds (15cm high and 45cm wide across the top) using a press-pan-type bed shaper. The plants were arranged on two rows on each bed, with 20 cm in-row and 40 cm between-row spacing. The plants were irrigated weekly as needed. Gas exchange parameters were investigated from June 9-11at end of vegetative phase under natural environmental conditions. The parameters of gas exchange were measured on the 5th and 6th nearly full expanded leaves between the hours of 07:00 and 20:00 during bright sunlight on clear and cloudless days. Determination of leaf net photosynthesis rate (Pn), stomatal conductance (gs) and transpiration (E) was made with Infra-red gas analyzer (LCA4, ADC Co. Ltd., Hoddesdon, UK).Instantaneous water use efficiency (WUEinst) and apparent quantum yield(AQY) were calculated as Pn/E andPn/PPFD ratios, respectively.
Result and discussion: The result showed that plant type had significant effect on all measured traits as well as record time. Interaction between plant type and record time were significant for PPFD, leaf temperature and net photosynthesis. The highest Pnof Lemon balm (8.97 µmol CO2 m-2 s-1), catnip (11.2 µmol CO2 m-2 s-1) and sweet basil (13.75 µmol CO2 m-2 s-1) were recorded at 9:00 when the photosynthetic photon flux density (PPFD) was 1488, 1598 and 1645 µmol photon m-2 s-1, respectively. Holy basil showed highest Pn (15.47 µmol CO2 m-2 s-1) at 10:00 when PPFD was 1821 µmol photon m-2 s-1.High irradiances caused photoinhibition of the four plants and it seems the four plants reach to light saturation point about 1500 µmol photon m-2 s-1.The midday depression of photosynthesis likely resulted primarily from long periods of high PPFD, limitation in stomatal conductance and high temperature. Catnip was more sensitive to high irradiance. The Pn had positive and significant correlation with gs in four plants. The stomatal conductance was also positively correlated with E in four plants. The plants represented double peak curve for WUE. The first and second peaks appeared at 9:00 and 17:00, respectively. The four plants also showed highest AQY at 7:00. There were significant difference between four plants for leaf temperature, gs, Pn, WUE and AQY. Lemon balm showed lower leaf temperature than other plants due to its high gs. The highest amounts of Pn, WUE and AQY were observed in holy basil.
Conclusion: In regard to Pn, WUE and AQY, it seems holy basil and sweet basil can tolerate weather condition of Ahvaz.

کلیدواژه‌ها [English]

  • Leaf temperature
  • Photosynthesis efficiency
  • stomatal conductance
  • Transpiration
  • Water use efficiency
1- Aharizad S., Rahimi M.H., Moghadam M., and Mohebalipour N. 2012. Study of genetic diversity in lemon balm (Melissa officinalisL.) populations based on morphological traits and essential oils content. Annals of Biological Research, 3 (12):5748-5753.
2- Chandra S., Lata H., Khan I.A., and Elsohly M.A. 2011. Temperature response of photosynthesis in different drug and fiber varieties of Cannabis sativa L. Physiology and Molecular Biology of Plants, 17(3):297–303.
3- Fattahi M., Nazeri V., Sefidkon F., and Zamani Z. 2013. Autecology of DracocephalumkotschyiBioss. in Iran. Iranian Journal of Medicinal and Aromatic plants, 29 (2): 325-342. (in Persian with English abstract)
4- Fu Q.S., Zhao B., Wang Y.J., Ren S., and Guo Y.D. 2010. Stomatal development and associated photosynthetic performance of capsicum in response to differential light availabilities. Photosynthetica, 48 (2): 189-198.
5- Gong J.R., Zhao A.F., Huang Y.M., Zhang X.S., and Zhang C.L. 2006. Water relations, gas exchange, photochemical efficiency, and peroxidative stress of four plant species in the Heihe drainage basin of northern China. Photosynthetica, 44 (3): 355-364.
6- Kang Y., Outlaw W.H.J., Fiore G.B., and Riddle K.A. 2007.Guard cell apoplasticphotosynthate accumulation corresponds to a phloem-loading mechanism. Journal of Experimental Botany, 58 (15/16): 4061–4070.
7- Lambers H. 1998. Responses to availability of water. p. 154-191. In Lamberset al (ed.) Plant Physiological Ecology. Springer-Verlag, New York – Berlin –Heidelberg.
8- Lee S.H., Tewari R.K., Hahn E.J., and Paek K.Y. 2007. Photon flux density and light quality induce changes in growth, stomatal development, photosynthesis and transpiration of Withaniasomnifera (L.) Dunal. Plantlets. Plant Cell Tissue Organ Culture, 90:141–151.
9- Liu M.Z., Jiang G.M., Li Y.G., Gao L.M., Niu S.L., Cui H.X., and Ding L. 2003.Gas exchange, photochemical efficiency, and leaf water potential in three Salix species. Photosynthetica, 41 (3): 393-398.
10- MahmoodiSourestani M. 2013. Diurnal variations of gas exchange characteristics in leaves of anise hyssop (Agastachefoeniculum) under normal, drought stress and recovery conditions. Journal of Medicinal Plants and By-products, 1: 91-101.
11- Misra A., Dwivedi S., Srivastava A.K., Tewari D.K., Khan A., and Kumar R. 2006. Low iron stress nutrition for evaluation of Fe-efficient genotype physiology, photosynthesis, and essential monoterpene oil (s) yield of Ocimum sanctum. Photosynthetica, 44 (3): 474-477.
12- Modhej A. 2008. A study of the effect of terminal heat stress on source restriction and grain yield in bread wheat (Triticumaestivum L.) genotypes under khuzestan conditions. Iranian Journal of Field Crop Science, 39 (1): 89-97. (in Persian with English abstract)
13- Moradkhani H., Sargsyan E., Bibak H., Naseri B., Sadat-Hosseini M., Fayazi-Barjin A., and Meftahizade H. 2010. Melissa officinalisL., A valuable medicine plant: A review. Journal of Medicinal Plants Research, 4 (25): 2753-2759.
14- Moutinho-Pereira J., Magalhaes N., Goncalves B., Bacelar E., Brito M., and Correia C. 2007. Gas exchange and water relations of three VitisviniferaL. cultivars growing under Mediterranean climate. Photosynthetica, 45 (2): 202-207.
15- Munne-Bosch S., Nogues S., and Alegre L. 1999. Diurnal variations of photosynthesis and dew absorption by leaves in two evergreen shrubs growing in Mediterranean field conditions. New Phytologist, 144, 109-119.
16- Noohi K., Fattahi A., and Fateh Sh. 2013. The impact of heat stress on the citrus crop in southern Iran. Journal of Climate Research, 3 (9):13-22. (in Persian)
17- Rahnama A. 2010. The study on the relative tolerance of rapeseed (Brassica napus L.) to heat stress and drought of late season in the southern of Khuzestan. Crop Physiology Journal, 2 (1): 93-110. (in Persian)
18- Raina A.P., Kumar A., and Dutta M. 2013. Chemical characterization of aroma compounds in essential oil isolated from ‘‘Holy Basil’’ (Ocimumtenuiflorum L.) grown in India. Genetic Resources and Crop Evolution, 60 (5): 1727-1735.
19- Roozban M.R., Arzani K., and Latifi S.M. 2009. Diurnal variations in photosynthetic gas exchange in two Iranian pistachio (Pistaciavera L.) cultivars. Seed and Plant Production Journal, 25 (3): 285-300. (in Persian with English abstract)
20- Safaei-Ghomi J., Jafari-Bidgoli Z., and Batooli H. 2009. Volatile constituents analysis of Nepetacatariafrom central Iran. Chemistry of Natural Compounds, 45 (6): 913-915.
21- Thompson L.K., Blaylock R., Sturtevant J.M., and Brudvig G.W. 1989. Molecular basis of the heat denaturation of photosystem II. Biochemistry, 28:6686–6695.
22- Wilson K.B., Baldocchi D.D., and Hanson P.J. 2000. Quantifying stomatal and non-stomatal limitations to carbon assimilation resulting from leaf aging and drought in mature deciduous tree species. Tree Physiology, 20: 787-797.
CAPTCHA Image