Effect of exogenous chitosan, salicylic acid and their combination on some physiological parameters of Citrullus colocynthis (L.) under drought stress

Document Type : Original Article

Authors

1 Department of Horticulture, Faculty of Agriculture, University of Zabol, Zabol, Iran

2 Department of Plant Breeding and Biotechnology(PBB)/ Faculty of Agriculture/ University of Zabol/ Zabol/ Iran

3 Department of Biology, Faculty of Science, University of Zabol, Zabol, Iran

Abstract

Drought stress is alarmingly on the rise over the past decades. The growth regulators including salicylic acid (SA) and chitosan are being successfully used to protect plants against biotic and abiotic stresses. To investigate the effect of SA, chitosan and their combination on biochemical traits and cucurbitacin contents in Citrullus colocynthis (L.) under different levels of drought stress, four irrigation levels (control (100% Field capacity: FC), 75, 50 and 25% FC) along with three different treatments by administration of SA and chitosan (150 mg L-1), and their combinations were used. Drought stress significantly increased the amount of sugar, proline, lipid peroxidation and the activity of antioxidant enzymes such as superoxide dismutase (SOD) and catalase (CAT) while decreased growth parameters, protein, leaf relative water content (RWC), chlorophyll and carotenoid contents. Although SA could increase some biochemical traits including sugar, chlorophyll and carotenoid contents only in severe level of drought stress, chitosan and the combined treatment exerted beneficial effects in almost all levels of irrigation. Furthermore, combination of SA and chitosan induced more protective effects compared to only chitosan treatment in increasing proline and the activities of SOD and CAT. Combined treatment was also effective in increasing cucurbitacin B, C and L contents but not cucurbitacin E. Combination of SA and chitosan showed the major impact on improving physiological parameters and cucurbitacin contents of C. colocynthis and therefore could be a potential candidate to protect the plant against adverse effects of drought stress.

Keywords


 Abu-Muriefah, S. S. 2013. Effect of chitosan on common bean (Phaseolus vulgaris L.) plants grown under water stress conditions. International Research Journal of Agricultural Science and Soil Science, 3, (6) 192-199.

Arfan, M., H. R. Athar and M. Ashraf. 2007. Does exogenous application of salicylic acid through the rooting medium modulate growth and photosynthetic capacity in two differently adapted spring wheat cultivars under salt stress? Journal of plant physiology, 164, (6) 685-694.

Azhar, N., B. Hussain, M. Y. Ashraf and K. Y. Abbasi. 2011. Water stress mediated changes in growth, physiology and secondary metabolites of desi ajwain (Trachyspermum ammi L.). Pakistan Journal of Botany, 43, (9) 15-19.

  Barnabás, B., K. Jäger and A. Fehér. 2008. The effect of drought and heat stress on reproductive processes in cereals. Plant, cell & environment, 31, (1) 11-38.

Bates, L. S., R. P. Waldren and I. Teare. 1973. Rapid determination of free proline for water-stress studies. Plant and soil, 39, (1) 205-207.

Bettaieb, I., N. Zakhama, W. A. Wannes, M. Kchouk and B. Marzouk. 2009. Water deficit effects on Salvia officinalis fatty acids and essential oils composition. Scientia horticulturae, 120, (2) 271-275.

  Boonlertnirun, S., S. Meechoui and E. Sarobol. 2010. Physiological and morphological responses of field corn seedlings to chitosan under hypoxic conditions. Scienceasia, 36, (2) 89-93.

    Bradford, M. M. 1976. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Analytical biochemistry, 72, (1-2) 248-254.

  Budak, H., M. Kantar and K. Yucebilgili Kurtoglu. 2013. Drought tolerance in modern and wild wheat. The Scientific World Journal, 2013,

  Cock, J., S. Yoshida and D. A. Forno. 1976. Laboratory manual for physiological studies of rice. Int. Rice Res. Inst.

Dianat, M., M. J. Saharkhiz and I. Tavassolian. 2016. Salicylic acid mitigates drought stress in Lippia citriodora L.: Effects on biochemical traits and essential oil yield. Biocatalysis and Agricultural Biotechnology, 8, 286-293.

Diwan, F., I. Abdel Hassan and S. Mohammed. 2000. Effect of saponin on mortality and histopathological changes in mice. EMHJ-Eastern Mediterranean Health Journal, 6 (2-3), 345-351, 2000.

Farooq, M., A. Wahid, D. J. Lee, S. Cheema and T. Aziz. 2010. Drought stress: comparative time course action of the foliar applied glycinebetaine, salicylic acid, nitrous oxide, brassinosteroids and spermine in improving drought resistance of rice. Journal of Agronomy and Crop Science, 196, (5) 336-345.

  Farouk, S. and A. R. Amany. 2012. Improving growth and yield of cowpea by foliar application of chitosan under water stress. Egyptian Journal of Biology, 14, 14-16.

Farouk, S., K. Ghoneem and A. A. Ali. 2008. Induction and expression of systemic resistance to downy mildew disease in cucumber by elicitors. Egypt J Phytopathol, 36, (1-2) 95-111.

Farouk, S., A. Mosa, A. Taha and A. El-Gahmery. 2011. Protective effect of humic acid and chitosan on radish (Raphanus sativus, L. var. sativus) plants subjected to cadmium stress. Journal of Stress Physiology & Biochemistry, 7, (2)

  Fayez, K. A. and S. A. Bazaid. 2014. Improving drought and salinity tolerance in barley by application of salicylic acid and potassium nitrate. Journal of the Saudi Society of Agricultural Sciences, 13, (1) 45-55.

Ghoname A, M. El-Nemr, A. Abdel-Mawgoud and W. El-Tohamy. 2010. Enhancement of sweet pepper crop growth and production by application of biological, organic and nutritional solutions. Research Journal of Agriculture and Biological Sciences, 6:349-355

Gill, S. S. and N. Tuteja. 2010. Reactive oxygen species and antioxidant machinery in abiotic stress tolerance in crop plants. Plant physiology and biochemistry, 48, (12) 909-930.

Górnik, K., M. Grzesik and B. Romanowska-Duda. 2008. The effect of chitosan on rooting of grapevine cuttings and on subsequent plant growth under drought and temperature stress. Journal of Fruit and Ornamental Plant Research, 16, 333-343.

  Guan, Y.-J., J. Hu, X.-J. Wang and C.-X. Shao. 2009. Seed priming with chitosan improves maize germination and seedling growth in relation to physiological changes under low temperature stress. Journal of Zhejiang University Science B, 10, (6) 427-433.

  Habibi, G. 2012. Exogenous salicylic acid alleviates oxidative damage of barley plants under drought stress. Acta Biologica Szegediensis, 56, (1) 57-63.

    Hameed, A., N. Bibi, J. Akhter and N. Iqbal. 2011. Differential changes in antioxidants, proteases, and lipid peroxidation in flag leaves of wheat genotypes under different levels of water deficit conditions. Plant Physiology and Biochemistry, 49, (2) 178-185.

Hatam, N. A., D. A. Whiting and N. J. Yousif. 1989. Cucurbitacin glycosides from Citrullus colocynthis. Phytochemistry, 28, (4) 1268-1271.

Hayat, S., S. A. Hasan, Q. Fariduddin and A. Ahmad. 2008. Growth of tomato (Lycopersicon esculentum) in response to salicylic acid under water stress. Journal of Plant Interactions, 3, (4) 297-304.

Hendawy, S. and K. A. Khalid. 2005. Response of sage (Salvia officinalis L.) plants to zinc application under different salinity levels. J Appl Sci Res, 1, (2) 147-155.

Hodges, D. M., J. M. Delong, C. F. Forney and R. K. Prange. 1999. Improving the thiobarbituric acid-reactive-substances assay for estimating lipid peroxidation in plant tissues containing anthocyanin and other interfering compounds. Planta, 207, (4) 604-611.

   Horváth, E., G. Szalai and T. Janda. 2007. Induction of abiotic stress tolerance by salicylic acid signaling. Journal of Plant Growth Regulation, 26, (3) 290-300.

Irigoyen, J., D. Einerich and M. Sánchez‐Díaz. 1992. Water stress induced changes in concentrations of proline and total soluble sugars in nodulated alfalfa (Medicago sativa) plants. Physiologia plantarum, 84, (1) 55-60.

  Juan, M., R. M. Rivero, L. Romero and J. M. Ruiz. 2005. Evaluation of some nutritional and biochemical indicators in selecting salt-resistant tomato cultivars. Environmental and Experimental Botany, 54, (3) 193-201.

  Kabiri, R. and M. Naghizadeh. 2015. Exogenous acetylsalicylic acid stimulates physiological changes to improve growth, yield and yield components of barley under water stress condition. Journal of Plant Physiology and Breeding, 5, (1) 35-45.

Kabiri, R., F. Nasibi and H. Farahbakhsh. 2014. Effect of exogenous salicylic acid on some physiological parameters and alleviation of drought stress in Nigella sativa plant under hydroponic culture. Plant Protection Science, 50, (1) 43-51.

  Kang, G., G. Li, W. Xu, X. Peng, Q. Han, Y. Zhu and T. Guo. 2012. Proteomics reveals the effects of salicylic acid on growth and tolerance to subsequent drought stress in wheat. Journal of Proteome Research, 11, (12) 6066-6079.

Khandaker, L., A. A. Masum and S. Oba. 2011. Foliar application of salicylic acid improved the growth, yield and leaf's bioactive compounds in red amaranth (Amaranthus tricolor L.). Vegetable crops research bulletin, 74, 77.

Lai, Q.-X., Z.-Y. Bao, Z.-J. Zhu, Q.-Q. Qian and B.-Z. Mao. 2007. Effects of osmotic stress on antioxidant enzymes activities in leaf discs of P SAG12-IPT modified gerbera. Journal of Zhejiang University Science B, 8, (7) 458-464.

  Li, X.-M., S.-L. Tian, Z.-C. Pang, J.-Y. Shi, Z.-S. Feng and Y.-M. Zhang. 2009. Extraction of Cuminum cyminum essential oil by combination technology of organic solvent with low boiling point and steam distillation. Food chemistry, 115, (3) 1114-1119.

Malekpoor, F., A. G. Pirbalouti and A. Salimi. 2016. Effect of foliar application of chitosan on morphological and physiological characteristics of basil under reduced irrigation. Research on Crops, 17, (2) 354-359.

   Mandal, S. 2010. Induction of phenolics, lignin and key defense enzymes in eggplant (Solanum melongena L.) roots in response to elicitors. African Journal of Biotechnology, 9, (47) 8038-8047.

   Miao, Y., Z. Zhu, Q. Guo, H. Ma and L. Zhu. 2015. Alternate wetting and drying irrigation-mediated changes in the growth, photosynthesis and yield of the medicinal plant Tulipa edulis. Industrial Crops and Products, 66, 81-88.

    Miller, G., N. Suzuki, S. Ciftci‐Yilmaz and R. Mittler. 2010. Reactive oxygen species homeostasis and signalling during drought and salinity stresses. Plant, cell & environment, 33, (4) 453-467.

  Mishra, S., A. Jha and R. Dubey. 2011. Arsenite treatment induces oxidative stress, upregulates antioxidant system, and causes phytochelatin synthesis in rice seedlings. Protoplasma, 248, (3) 565-577.

  Mohamed, S. 2018. Effect of chitosan, putrescine and irrigation levels on the drought tolerance of sour orange seedlings. Egyptian Journal of Horticulture, 45, (2) 257-273.

   Noctor, G. and C. H. Foyer. 1998. Ascorbate and glutathione: keeping active oxygen under control. Annual review of plant biology, 49, (1) 249-279.

Pirbalouti, A. G., M. R. Samani, M. Hashemi and H. Zeinali. 2014. Salicylic acid affects growth, essential oil and chemical compositions of thyme (Thymus daenensis Celak.) under reduced irrigation. Plant growth regulation, 72, (3) 289-301.

Pirzad, A., M. R. Shakiba, S. Zehtab-Salmasi, S. A. Mohammadi, R. Darvishzadeh and A. Samadi. 2011. Effect of water stress on leaf relative water content, chlorophyll, proline and soluble carbohydrates in Matricaria chamomilla L. Journal of Medicinal Plants Research, 5, (12) 2483-2488.

Rao, S., A. Qayyum, A. Razzaq, M. Ahmad, I. Mahmood and A. Sher. 2012. Role of foliar application of salicylic acid and L-tryptophan in drought tolerance of maize. J Anim Plant Sci, 22, (3) 768-772.

    Rivas-San Vicente, M. and J. Plasencia. 2011. Salicylic acid beyond defence: its role in plant growth and development. Journal of experimental botany, 62, (10) 3321-3338.

Rowshan, V., M. K. Khoi and K. Javidnia. 2010. Effects of salicylic acid on quality and quantity of essential oil components in Salvia macrosiphon. Journal of Biological and Environmental Sciences, 4(11), 77-82.

  Sankar, B., C. A. Jaleel, P. Manivannan, A. Kishorekumar, R. Somasundaram and R. Panneerselvam. 2007. Effect of paclobutrazol on water stress amelioration through antioxidants and free radical scavenging enzymes in Arachis hypogaea L. Colloids and Surfaces B: Biointerfaces, 60, (2) 229-235.

Sayfzadeh, S. and M. Rashidi. 2011. Response of antioxidant enzymes activities of sugar beet to drought stress. J Agric Biol Sci, 6, (4) 27-33.

   Seger, C., S. Sturm, M. E. Mair, E. P. Ellmerer and H. Stuppner. 2005. 1H and 13C NMR signal assignment of cucurbitacin derivatives from Citrullus colocynthis (L.) Schrader and Ecballium elaterium L.(Cucurbitaceae). Magnetic Resonance in Chemistry, 43, (6) 489-491

   Sharma, M., S. K. Gupta, B. Majumder, V. K. Maurya, F. Deeba, A. Alam and V. Pandey. 2017. Salicylic acid mediated growth, physiological and proteomic responses in two wheat varieties under drought stress. Journal of proteomics, 163, 28-51.

   Sharma, P., A. B. Jha, R. S. Dubey and M. Pessarakli. 2012. Reactive oxygen species, oxidative damage, and antioxidative defense mechanism in plants under stressful conditions. Journal of botany, Volume 2012, Article ID 217037, 26 page

Shekari, F., V. Soltaniband, A. Javanmard and A. Abbasi. 2016. The impact of drought stress at different stages of development on water relations, stomatal density and quality changes of rapeseed (Brassica napus L.). Iran Agricultural Research, 34, (2) 81-90.

  Shobbar, M.-S., O. Azhari, Z.-S. Shobbar, V. Niknam, H. Askari, M. Pessarakli and H. Ebrahimzadeh. 2012. Comparative analysis of some physiological responses of rice seedlings to cold, salt, and drought stresses. Journal of plant nutrition, 35, (7) 1037-1052.

   Solinas, V., S. Deiana, C. Gessa, A. Bazzoni, M. Loddo and D. Satta. 1996. Effect of water and nutritional conditions on the Rosmarinus officinalis L., phenolic fraction and essential oil yields. Rivista Italiana EPPOS, 19, 189-198.

  Srivastava, S. and R. Dubey. 2011. Manganese-excess induces oxidative stress, lowers the pool of antioxidants and elevates activities of key antioxidative enzymes in rice seedlings. Plant Growth Regulation, 64, (1) 1-16.

Vurayai, R., V. Emongor and B. Moseki. 2011. Physiological responses of bambara groundnut (Vigna subterranea L. Verdc) to short periods of water stress during different developmental stages. Asian Journal of Agricultural Sciences, 3, (1) 37-43.

   Xie, W., P. Xu and Q. Liu. 2001. Antioxidant activity of water-soluble chitosan derivatives. Bioorganic & Medicinal Chemistry Letters, 11, (13) 1699-1701.

Xu, Q.-J., Y.-G. Nian, X.-C. Jin, C.-Z. Yan, L. Jin and G.-M. Jiang. 2007. Effects of chitosan on growth of an aquatic plant (Hydrilla verticillata) in polluted waters with different chemical oxygen demands. Journal of Environmental Sciences, 19, (2) 217-221.

  Yang, F., J. Hu, J. Li, X. Wu and Y. Qian. 2009. Chitosan enhances leaf membrane stability and antioxidant enzyme activities in apple seedlings under drought stress. Plant Growth Regulation, 58, (2) 131-136.

Yazdanpanah, S., A. Baghizadeh and F. Abbassi. 2011. The interaction between drought stress and salicylic and ascorbic acids on some biochemical characteristics of Satureja hortensis. African Journal of Agricultural Research, 6, (4) 798-807.

 

 

 Abu-Muriefah, S. S. 2013. Effect of chitosan on common bean (Phaseolus vulgaris L.) plants grown under water stress conditions. International Research Journal of Agricultural Science and Soil Science, 3, (6) 192-199.
Arfan, M., H. R. Athar and M. Ashraf. 2007. Does exogenous application of salicylic acid through the rooting medium modulate growth and photosynthetic capacity in two differently adapted spring wheat cultivars under salt stress? Journal of plant physiology, 164, (6) 685-694.
Azhar, N., B. Hussain, M. Y. Ashraf and K. Y. Abbasi. 2011. Water stress mediated changes in growth, physiology and secondary metabolites of desi ajwain (Trachyspermum ammi L.). Pakistan Journal of Botany, 43, (9) 15-19.
  Barnabás, B., K. Jäger and A. Fehér. 2008. The effect of drought and heat stress on reproductive processes in cereals. Plant, cell & environment, 31, (1) 11-38.
Bates, L. S., R. P. Waldren and I. Teare. 1973. Rapid determination of free proline for water-stress studies. Plant and soil, 39, (1) 205-207.
Bettaieb, I., N. Zakhama, W. A. Wannes, M. Kchouk and B. Marzouk. 2009. Water deficit effects on Salvia officinalis fatty acids and essential oils composition. Scientia horticulturae, 120, (2) 271-275.
  Boonlertnirun, S., S. Meechoui and E. Sarobol. 2010. Physiological and morphological responses of field corn seedlings to chitosan under hypoxic conditions. Scienceasia, 36, (2) 89-93.
    Bradford, M. M. 1976. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Analytical biochemistry, 72, (1-2) 248-254.
  Budak, H., M. Kantar and K. Yucebilgili Kurtoglu. 2013. Drought tolerance in modern and wild wheat. The Scientific World Journal, 2013,
  Cock, J., S. Yoshida and D. A. Forno. 1976. Laboratory manual for physiological studies of rice. Int. Rice Res. Inst.
Dianat, M., M. J. Saharkhiz and I. Tavassolian. 2016. Salicylic acid mitigates drought stress in Lippia citriodora L.: Effects on biochemical traits and essential oil yield. Biocatalysis and Agricultural Biotechnology, 8, 286-293.
Diwan, F., I. Abdel Hassan and S. Mohammed. 2000. Effect of saponin on mortality and histopathological changes in mice. EMHJ-Eastern Mediterranean Health Journal, 6 (2-3), 345-351, 2000.
Farooq, M., A. Wahid, D. J. Lee, S. Cheema and T. Aziz. 2010. Drought stress: comparative time course action of the foliar applied glycinebetaine, salicylic acid, nitrous oxide, brassinosteroids and spermine in improving drought resistance of rice. Journal of Agronomy and Crop Science, 196, (5) 336-345.
  Farouk, S. and A. R. Amany. 2012. Improving growth and yield of cowpea by foliar application of chitosan under water stress. Egyptian Journal of Biology, 14, 14-16.
Farouk, S., K. Ghoneem and A. A. Ali. 2008. Induction and expression of systemic resistance to downy mildew disease in cucumber by elicitors. Egypt J Phytopathol, 36, (1-2) 95-111.
Farouk, S., A. Mosa, A. Taha and A. El-Gahmery. 2011. Protective effect of humic acid and chitosan on radish (Raphanus sativus, L. var. sativus) plants subjected to cadmium stress. Journal of Stress Physiology & Biochemistry, 7, (2)
  Fayez, K. A. and S. A. Bazaid. 2014. Improving drought and salinity tolerance in barley by application of salicylic acid and potassium nitrate. Journal of the Saudi Society of Agricultural Sciences, 13, (1) 45-55.
Ghoname A, M. El-Nemr, A. Abdel-Mawgoud and W. El-Tohamy. 2010. Enhancement of sweet pepper crop growth and production by application of biological, organic and nutritional solutions. Research Journal of Agriculture and Biological Sciences, 6:349-355
Gill, S. S. and N. Tuteja. 2010. Reactive oxygen species and antioxidant machinery in abiotic stress tolerance in crop plants. Plant physiology and biochemistry, 48, (12) 909-930.
Górnik, K., M. Grzesik and B. Romanowska-Duda. 2008. The effect of chitosan on rooting of grapevine cuttings and on subsequent plant growth under drought and temperature stress. Journal of Fruit and Ornamental Plant Research, 16, 333-343.
  Guan, Y.-J., J. Hu, X.-J. Wang and C.-X. Shao. 2009. Seed priming with chitosan improves maize germination and seedling growth in relation to physiological changes under low temperature stress. Journal of Zhejiang University Science B, 10, (6) 427-433.
  Habibi, G. 2012. Exogenous salicylic acid alleviates oxidative damage of barley plants under drought stress. Acta Biologica Szegediensis, 56, (1) 57-63.
    Hameed, A., N. Bibi, J. Akhter and N. Iqbal. 2011. Differential changes in antioxidants, proteases, and lipid peroxidation in flag leaves of wheat genotypes under different levels of water deficit conditions. Plant Physiology and Biochemistry, 49, (2) 178-185.
Hatam, N. A., D. A. Whiting and N. J. Yousif. 1989. Cucurbitacin glycosides from Citrullus colocynthis. Phytochemistry, 28, (4) 1268-1271.
Hayat, S., S. A. Hasan, Q. Fariduddin and A. Ahmad. 2008. Growth of tomato (Lycopersicon esculentum) in response to salicylic acid under water stress. Journal of Plant Interactions, 3, (4) 297-304.
Hendawy, S. and K. A. Khalid. 2005. Response of sage (Salvia officinalis L.) plants to zinc application under different salinity levels. J Appl Sci Res, 1, (2) 147-155.
Hodges, D. M., J. M. Delong, C. F. Forney and R. K. Prange. 1999. Improving the thiobarbituric acid-reactive-substances assay for estimating lipid peroxidation in plant tissues containing anthocyanin and other interfering compounds. Planta, 207, (4) 604-611.
   Horváth, E., G. Szalai and T. Janda. 2007. Induction of abiotic stress tolerance by salicylic acid signaling. Journal of Plant Growth Regulation, 26, (3) 290-300.
Irigoyen, J., D. Einerich and M. Sánchez‐Díaz. 1992. Water stress induced changes in concentrations of proline and total soluble sugars in nodulated alfalfa (Medicago sativa) plants. Physiologia plantarum, 84, (1) 55-60.
  Juan, M., R. M. Rivero, L. Romero and J. M. Ruiz. 2005. Evaluation of some nutritional and biochemical indicators in selecting salt-resistant tomato cultivars. Environmental and Experimental Botany, 54, (3) 193-201.
  Kabiri, R. and M. Naghizadeh. 2015. Exogenous acetylsalicylic acid stimulates physiological changes to improve growth, yield and yield components of barley under water stress condition. Journal of Plant Physiology and Breeding, 5, (1) 35-45.
Kabiri, R., F. Nasibi and H. Farahbakhsh. 2014. Effect of exogenous salicylic acid on some physiological parameters and alleviation of drought stress in Nigella sativa plant under hydroponic culture. Plant Protection Science, 50, (1) 43-51.
  Kang, G., G. Li, W. Xu, X. Peng, Q. Han, Y. Zhu and T. Guo. 2012. Proteomics reveals the effects of salicylic acid on growth and tolerance to subsequent drought stress in wheat. Journal of Proteome Research, 11, (12) 6066-6079.
Khandaker, L., A. A. Masum and S. Oba. 2011. Foliar application of salicylic acid improved the growth, yield and leaf's bioactive compounds in red amaranth (Amaranthus tricolor L.). Vegetable crops research bulletin, 74, 77.
Lai, Q.-X., Z.-Y. Bao, Z.-J. Zhu, Q.-Q. Qian and B.-Z. Mao. 2007. Effects of osmotic stress on antioxidant enzymes activities in leaf discs of P SAG12-IPT modified gerbera. Journal of Zhejiang University Science B, 8, (7) 458-464.
  Li, X.-M., S.-L. Tian, Z.-C. Pang, J.-Y. Shi, Z.-S. Feng and Y.-M. Zhang. 2009. Extraction of Cuminum cyminum essential oil by combination technology of organic solvent with low boiling point and steam distillation. Food chemistry, 115, (3) 1114-1119.
Malekpoor, F., A. G. Pirbalouti and A. Salimi. 2016. Effect of foliar application of chitosan on morphological and physiological characteristics of basil under reduced irrigation. Research on Crops, 17, (2) 354-359.
   Mandal, S. 2010. Induction of phenolics, lignin and key defense enzymes in eggplant (Solanum melongena L.) roots in response to elicitors. African Journal of Biotechnology, 9, (47) 8038-8047.
   Miao, Y., Z. Zhu, Q. Guo, H. Ma and L. Zhu. 2015. Alternate wetting and drying irrigation-mediated changes in the growth, photosynthesis and yield of the medicinal plant Tulipa edulis. Industrial Crops and Products, 66, 81-88.
    Miller, G., N. Suzuki, S. Ciftci‐Yilmaz and R. Mittler. 2010. Reactive oxygen species homeostasis and signalling during drought and salinity stresses. Plant, cell & environment, 33, (4) 453-467.
  Mishra, S., A. Jha and R. Dubey. 2011. Arsenite treatment induces oxidative stress, upregulates antioxidant system, and causes phytochelatin synthesis in rice seedlings. Protoplasma, 248, (3) 565-577.
  Mohamed, S. 2018. Effect of chitosan, putrescine and irrigation levels on the drought tolerance of sour orange seedlings. Egyptian Journal of Horticulture, 45, (2) 257-273.
   Noctor, G. and C. H. Foyer. 1998. Ascorbate and glutathione: keeping active oxygen under control. Annual review of plant biology, 49, (1) 249-279.
Pirbalouti, A. G., M. R. Samani, M. Hashemi and H. Zeinali. 2014. Salicylic acid affects growth, essential oil and chemical compositions of thyme (Thymus daenensis Celak.) under reduced irrigation. Plant growth regulation, 72, (3) 289-301.
Pirzad, A., M. R. Shakiba, S. Zehtab-Salmasi, S. A. Mohammadi, R. Darvishzadeh and A. Samadi. 2011. Effect of water stress on leaf relative water content, chlorophyll, proline and soluble carbohydrates in Matricaria chamomilla L. Journal of Medicinal Plants Research, 5, (12) 2483-2488.
Rao, S., A. Qayyum, A. Razzaq, M. Ahmad, I. Mahmood and A. Sher. 2012. Role of foliar application of salicylic acid and L-tryptophan in drought tolerance of maize. J Anim Plant Sci, 22, (3) 768-772.
    Rivas-San Vicente, M. and J. Plasencia. 2011. Salicylic acid beyond defence: its role in plant growth and development. Journal of experimental botany, 62, (10) 3321-3338.
Rowshan, V., M. K. Khoi and K. Javidnia. 2010. Effects of salicylic acid on quality and quantity of essential oil components in Salvia macrosiphon. Journal of Biological and Environmental Sciences, 4(11), 77-82.
  Sankar, B., C. A. Jaleel, P. Manivannan, A. Kishorekumar, R. Somasundaram and R. Panneerselvam. 2007. Effect of paclobutrazol on water stress amelioration through antioxidants and free radical scavenging enzymes in Arachis hypogaea L. Colloids and Surfaces B: Biointerfaces, 60, (2) 229-235.
Sayfzadeh, S. and M. Rashidi. 2011. Response of antioxidant enzymes activities of sugar beet to drought stress. J Agric Biol Sci, 6, (4) 27-33.
   Seger, C., S. Sturm, M. E. Mair, E. P. Ellmerer and H. Stuppner. 2005. 1H and 13C NMR signal assignment of cucurbitacin derivatives from Citrullus colocynthis (L.) Schrader and Ecballium elaterium L.(Cucurbitaceae). Magnetic Resonance in Chemistry, 43, (6) 489-491
   Sharma, M., S. K. Gupta, B. Majumder, V. K. Maurya, F. Deeba, A. Alam and V. Pandey. 2017. Salicylic acid mediated growth, physiological and proteomic responses in two wheat varieties under drought stress. Journal of proteomics, 163, 28-51.
   Sharma, P., A. B. Jha, R. S. Dubey and M. Pessarakli. 2012. Reactive oxygen species, oxidative damage, and antioxidative defense mechanism in plants under stressful conditions. Journal of botany, Volume 2012, Article ID 217037, 26 page
Shekari, F., V. Soltaniband, A. Javanmard and A. Abbasi. 2016. The impact of drought stress at different stages of development on water relations, stomatal density and quality changes of rapeseed (Brassica napus L.). Iran Agricultural Research, 34, (2) 81-90.
  Shobbar, M.-S., O. Azhari, Z.-S. Shobbar, V. Niknam, H. Askari, M. Pessarakli and H. Ebrahimzadeh. 2012. Comparative analysis of some physiological responses of rice seedlings to cold, salt, and drought stresses. Journal of plant nutrition, 35, (7) 1037-1052.
   Solinas, V., S. Deiana, C. Gessa, A. Bazzoni, M. Loddo and D. Satta. 1996. Effect of water and nutritional conditions on the Rosmarinus officinalis L., phenolic fraction and essential oil yields. Rivista Italiana EPPOS, 19, 189-198.
  Srivastava, S. and R. Dubey. 2011. Manganese-excess induces oxidative stress, lowers the pool of antioxidants and elevates activities of key antioxidative enzymes in rice seedlings. Plant Growth Regulation, 64, (1) 1-16.
Vurayai, R., V. Emongor and B. Moseki. 2011. Physiological responses of bambara groundnut (Vigna subterranea L. Verdc) to short periods of water stress during different developmental stages. Asian Journal of Agricultural Sciences, 3, (1) 37-43.
   Xie, W., P. Xu and Q. Liu. 2001. Antioxidant activity of water-soluble chitosan derivatives. Bioorganic & Medicinal Chemistry Letters, 11, (13) 1699-1701.
Xu, Q.-J., Y.-G. Nian, X.-C. Jin, C.-Z. Yan, L. Jin and G.-M. Jiang. 2007. Effects of chitosan on growth of an aquatic plant (Hydrilla verticillata) in polluted waters with different chemical oxygen demands. Journal of Environmental Sciences, 19, (2) 217-221.
  Yang, F., J. Hu, J. Li, X. Wu and Y. Qian. 2009. Chitosan enhances leaf membrane stability and antioxidant enzyme activities in apple seedlings under drought stress. Plant Growth Regulation, 58, (2) 131-136.
Yazdanpanah, S., A. Baghizadeh and F. Abbassi. 2011. The interaction between drought stress and salicylic and ascorbic acids on some biochemical characteristics of Satureja hortensis. African Journal of Agricultural Research, 6, (4) 798-807.