Effect of Drought Stress on Physio-morphological Characteristics and Proline Content of Three Varieties of Petunia

Document Type : Research Article


1 Ferdowsi University of Mashhad

2 ujm21


Introduction: Water deficiency is one of important abiotic stresses that severely effects on plant growth. The effects of drought range from morphological to molecular levels and are evident at all phenological stages of plant growth at whatever stage the water deficit takes place. Growth is accomplished through cell division, cell enlargement and differentiation, and involves genetic, physiological, ecological and morphological events and their complex interactions. The quality and quantity of plant growth depend on these events, which are affected by water deficit. Cell growth is one of the most drought-sensitive physiological processes due to the reduction in turgor pressure. Under severe water deficiency, cell elongation of higher plants can be inhibited by interruption of water flow from the xylem to the surrounding elongating cells. Impaired mitosis, cell elongation and expansion result in reduced plant height, leaf area and crop growth under drought. Chlorophyll content is one of the major factors affecting photosynthetic capacity changing in chlorophyll content of plant under drought stress has been observed in different plant species and its intensity depends on stress rate and duration. Chlorophyll content of leaf is indicator of photosynthetic capability of plant tissues. In the mid-80s, RWC was introduced as a best criterion for plant water status which, afterwards was used instead of plant water potential as RWC referring to its relation with cell volume, accurately can indicate the balance between absorbed water by plant and consumed through transpiration.
Materials and Methods: To study the effects of drought stress on three varieties of petunia, a factorial experiment based on randomized complete block design with four replications was conducted. The treatments consisted of four irrigation levels ((100% control), 80%, 60% and 40% of field capacity) and three varieties of petunia (Supercascade, Tango blue and Tango white). After planting and transplanting and after full deployment in the pot, water stress treatments were applied on three varieties of petunias. At the end of each week fully blossomed flowers were counted, flower diameter, peduncle length and corolla length were measured. In order to determine the stability of the cell membrane electrolyte leakage index was measured. Specific leaf area (SLA) was determined. The amount of chlorophyll a, b, total and carotenoid and relative water content in the leaves were measured. Statistical analysis was performed using the software MSTAT-C. EXCEL was used for diagramming software. Means were compared using LSD test with a 0.05 significance level.
Results and Discussion: Results indicated that interaction impacts of variety and irrigation on dry weight, leaf area, flower number, flower diameter, length Corolla, chlorophyll content, electrolyte leakage, relative water content and proline content was significant. The most shoot dry weight (76/1 g) was in control stress (100% FC) and Tango White variety. Also the most leaf dry weight (07/2 g) and root dry weight (g 43/0) were in Tango Blue variety. With increasing drought stress from 100% FC to 40% FC, leaf area decreased in Supercascade from 314 to 49, in Tango Blue from 405 to 44 and in Tango White from 459 to 69 cm2. In 80% FC, electrolyte leakage increased in all varieties (Supercascade variety 2%, Tango Blue 10% and in Tango White 3%) compared to control. Also electrolyte leakage increased in Supercascade 17%, in Tango Blue 9% and in Tango White10% in 40% FC compared to control. Comparison of interaction effects of drought stress and variety also showed the most proline had accumulated in Tango White and drought 40% of field capacity and then in Tango Blue and stress 40% of field capacity. Generally two varieties of Tango Blue and Tango White in control irrigation had better growth and also in low irrigation were more resistant.


1- Ahmadian A., Ghanbari V., and Siah Sar B. 2011. Effect of drought stress and use of organic and minerals fertilizers on remnants of the yield of German chamomile, Journal of Agricultural Ecology, 3(3): 383-395.
2- Ashraf M., and Foolad M.R. 2007. Roles of glycine, betaine and proline in improving plant abiotic stress resistance. Environmental and Experimental Botany, 59: 206-216.
3- Ashraf M.Y., Azmi A.R., Khan A.H., and Ala S.A. 1994. Effect of water stress on total phenols, peroxidase activity and chlorophyll content in wheat. Acta Physiologiae Plantarum, 16(3): 18 5-191.
4- Bates L.S., Waldren R.P., and Teare I.D. 1973. Rapid determination of free Pro for water stress studies. Plant Soil, 39: 205–217.
5- Blum A., and Ebercon A. 1981. Cell membrane stability as a measure of ought and heat tolerance in wheat. Crop Science, 21: 43-47.
6- Chylinski K.W., Lukaszewska A., and Kutnik K. 2007. Drought response of two bedding plants. Acta Physiology Plant, 29: 399-406.
7- Ghahraman A. 1994. Plant Systematics. Volume III. Tehran. Press center of academic publishing. 306 p.
8- Jensen N.F. 1988. Plant Breeding Methodology. Cornell Univercity. New York. Jogn Wiley, Pp: 379-380.
9- Kamali M., and Goldani M. 2016. Impact of manure treatments, compost and vermicompost on growth and flowering of Petunia hybrida in drought stress. Journal of Science and Technology of Greenhouse Culture, in press
10- Kao C.H. 1981. Senescence of rice leaves. VI. Comparative study of the metabolic changes of senescing turgid and water–stressed excised leaves. Plant and Cell Physiology, 22: 683–685.
11- Khosravi-Far S., Yarnia M., Khorshidi Benam M.B., and Hossein-Zade Moghbeli A.H. 2008. Effect of potassium on drought tolerance in potato variety Agria. In: Proc 10th Ir. Agron and Plants Breed Cong, 358p.
12- Lichtenthaler H. 1987. Chlorophylls and carotenoids: pigments of photosynthetic biomembranes. Methods in Enzymol, 148: 350-382.
13- Maggio A., Miyazaki S., Veronese P., Fujita T., Ibeas J.I., Damsz B., Narasimhan M.L., Hasegawa P.M., Joly R.J. and Bressan R.A. 2002. Does proline accumulation play an active role in stress-induced growth reduction? Plant Journal, 31(6): 699-712.
14- Mahajan S., and Tuteja N. 2005. Cold, salinity and drought stress: an overview. Archives of Biochemistry and Biophysics, 444: 139-158.
15- Mandal K., Saravanan R., and Maiti S. 2008. Effect of different levels of N, P and K on downy mildew (Peronospora plantaginis) and seed yield of Plantago ovata. Crop Protection, 27(6): 988-995.
16- Movahhedi Dehnavi M., Modarres Sanavi A.M., Soroush-Zade A., and Jalali M. 2004. Changes of proline, total soluble sugars, chlorophyll (SPAD) content and chlorophyll fluorescence in safflower varieties under drought stress and foliar application of zinc and manganese. Biaban, 9(1): 93-110.
17- Pessarkli M. 1999. Hand book of Plant and Crop Stress. Marcel Dekker Inc. 697 Pages.
18- Rahmani N., Aliabadi Farahani H., and Valadabadi S.A.R. 2008. Effects of nitrogen on oil yield and its component of calendula (Calendula officinalis L.) in drought stress conditions. Abstracts Book of the world Congress on Medicinal and Aromatic Plants, South Africa p.364.
19- Rajaram S., Van Ginkel M., and Fischer R.A. 1994. CIMMYT’s wheat breeding mega-environments (ME). Proceeding of the 8th International Wheat Genetics Symposium, pp.1101-1106. China Agricultural Scientech, Beijing, China.
20- Razmju J., Shariatmadari N., Khajedin J., Landi A., Namazi Y., Borhani M., and Aslani H. 2004. Effect of environmental stresses on plants of landscape and optimal conditions selected plants. Order of the Municipal Department of Parks and green spaces. Isfahan University of Technology.
21- Selahvarzi Y., Tehrani far A., and Gezanchian A. 2008. Physiomorphological changes under drought stress and rewatering in endemic and exotic turfgrasses. Journal of Horticultural Science and Technology, 9(3): 193-204.
22- Shaban M., Khaje A.A.A., Karim Zade H., Panah Pour A. 2009. Study on Drought Resistance of woody species suitable for green space development. Research in Agricultural Sciences, 1: 57-67.
23- Shams J., Etemdi N., Najafi P., and Rezaii A. 2010. Effect of drought stress on morphological characteristics of three varieties of petunias. Fifth National Conference on New Ideas in Agriculture.
24- Sreevalli Y., Baskaran K., Chandrashekara R., kuikkarni R., SuShil Hasan S., Samresh D., Kukre J., Ashok A., Sharmar Singh K., Srikant S., and Rakesh T. 2001. Preliminary observations on the effect of irrigation frequency and genotypes on yield and alkaloid concentration in petriwinkle. Journal of Medicinal and Aromatic Plant Science, 22: 356-358.
25- Turkan I., Bor M., Ozdemir F., and Koca H. 2005. Differential response of lipid peroxidation and antioxidant in the leaves of drought tolerance (P. acutifolius Gray) and drought sensitive (P. vulgaris L.) subjected to polyethyleneglycol mediated water stress. Plant Science, 168: 223-231.
26- Vieira R.D., Teerony D.M., and Egli D.B. 1991. Effect of drought stress on soybean seed germination and vigor. Journal Seed Technology, 16: 12-21.
27- Wang F., Zeng B., Sun Z., and Zhu C. 2009. Relationship between proline and Hg+2-induced oxidative stress in tolerant rice mutant. Archives of Environmental Contamination and Toxicology, 56(4): 723-731.
28- Zade Bagheri M., Al buali F., Sadeghi H., and Javanmardi Sh. 2014. The effect of irrigation on ionic changes, relative water content, proline content and appearance of Petunia. Journal of Horticultural Science (Agricultural Science and Technology), 28(3): 347-359.