1. Agboma, P., Jones, M. G. K., Peltonen-sainio, P., Hinkkanen, R., and Pehu, E. 1997. Exogenous glycine betaine enhances grain yield of maize, sorghum and wheat grown under two supplementary watering regimes. Journal of Agronomy and Crop Science 178: 29-37.
2. Allen, R. G., Pereira, L. S., Raes, D., and Smith, M. 1998. Crop evapotranspiration: guidelines for computing crop water requirements. FAO Irrigation and Drainage Paper No. 56. FAO, Rome, Italy. 300p.
3. Angadi, S. V., and Entz, M. H. 2002. Root system and water use patterns of different height sunflower cultivars. Agronomy Journal 94: 136-145.
4. Arasimowicz, M., and Floryszak-Wieczorek, J. 2007. Nitric oxide as a bioactive signaling molecule in plant stress responses. Plant Sciences 172: 876-887.
5. Bayat, S., Sepehri, A., Zare-abyaneh, H., and Abdollahi, M. R. 2010. Effect of Salicylic acid and paclobutrazol on some growth traits and yield of corn under drought stress. Quarterly Journal of Crop Ecophysiology 2 (1): 34-40. (in Persian with English abstract).
6. Bohnert, H. J., Nelson, D. E., and Jensen, R. E. 1995. Adaptation to environmental stresses. Plant Cell 7:1099-1111.
7. Cechin, I., Cardoso, G. S., Fumis, T. F., and Corniani, N. 2015. Nitric oxide reduces oxidative damage induced by water stress in sunflower plants. Bragantia 74 (2): 200-206.
8. Chaves, M. M., and Oliveira, M. M. 2004. Mechanisms underlying plant resilience to water deficits: prospects for water-saving agriculture. Journal of Experimental Botany 55: 2365-2384.
9. Chimenti. C. A., Pearson, J., and Hall, A. J. 2002. Osmotic adjustment and yield maintenance under drought in sunflower. Field Crop Research 75: 235-246.
10. Dadnia, M. R. 2012. Study the effect of water deficit stress and selenium foliar application on activity of some antioxidant enzymes in oil sunflower cultivars. Crop Physiology 4 (14): 71-81. (in Persian with English abstract).
11. Duan, X., Su, X., You, Y., Qu, H., Li, Y., and Jiang, Y. 2007. Effects of nitric oxide on pericarp browning of harvested longan fruit in relation to phenolic metabolism. Food Chemistry 104: 571-576.
12. El-Tayeb, M. A. 2005. Response of barley Gains to the interactive effect of salinity and salicylic acid. Plant Growth Regulation 45: 215-225.
13. Faraji, M., Mobasser, H., Ghanbari Malidareh, A., and Nazari, H. 2013. Effects of drought stress on gas exchange and water relations of red bean cultivars (Phaseolus vulgaris L.). Crop Production in Environmental Stress 4 (4):13-26. (in Persian with English abstract).
14. Fariduddin, Q., Hayat, S., and Ahmad, A. 2003. Salicylic acid influences net photosynthetic rate, carboxylation efficiency, nitrate reductase activity and seed yield in Brassica juncea. Photosynthetica 41: 281-284.
15. Farooq, M., Wahid, A., Lee, D. J., Cheema, S. A., and Aziz, T. 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.
16. Gaber Gomaa, S., Osama Kansowa, A., and Hossam Saad, E. 2010. Effects of various chemical agents for alleviation of drought stress in rice plants (Oryza sativa L.). Notulae Botanicae Horti Agrobotanici Cluj-Napoca 38 (1): 139-148.
17. Garcı´a-Mata, C., and Lamattina, L. 2001. Nitric oxide induces stomatal closure and enhances the adaptive plant responses against drought stress. Plant Physiology 126: 1196-1204.
18. Ghadami Firouzabadi, A., Raeini Sarjaz, M., Shahnazari, A., and Zareabyaneh, H. 2015. Water management and soil moisture changes in full, regulated deficit and partial root zone deficit irrigations in sunflower plant. Ph.D. Thesis in irrigation and drainage engineering. Sari Agricultural Sciences and Natural Resources University. Mazandaran. Iran. 176 pp. (in Persian with English abstract).
19. Ghobadi, R., Ghobadi, M., Jalali Honarmand, S., Farhadi, B., and Mondani, F. 2018. Study the responses of some leaf physiologic characteristics to different water and nitrogen levels in grainy maize (Zea mays L.). Iranian Journal of Field Crops Research 16 (3): 583-597. (in Persian with English abstract).
20. Habibi, Gh. 2013. Effect of drought stress and selenium spraying on photosynthesis and antioxidant activity of spring barley. Acta agriculturae Slovenica 101 (1): 31-39.
21. Hasanuzzaman, M., and Fujita, M. 2011. Selenium pretreatment up-regulates the antioxidant defense and methylglyoxalde toxification system and confers enhanced tolerance to drought stress in rapeseed seedlings. Biological Trace Element Research 143: 1758-1776.
22. Hussain, M., Malik, M. A., Farooq, M., Ashraf, M. Y., and Cheema, M. A. 2008. Improving drought tolerance by exogenous application of glycinebetaine and salicylic acid in sunflower. Journal of Agronomy and Crop Science 194 (3): 193-199.
23. Hussain, M., Malik, M. A., Farooq, M., Khan, M. B., Akram, M., and Saleem, M. F. 2009. Exogenous glycinebetaine and salicylic acid application improves water relations, allometry and quality of hybrid sunﬂower under water deﬁcit conditions. Journal of Agronomy and Crop Science 195: 98-109.
24. Hussain, S., Saleem, M. F., Ashraf, M. Y., Cheema, M. A., and Haq, M. A. 2010. Abscisic acid, a stress hormone helps in improving water relations and yield of sunflower (Helianthus annuus L.) hybrids under drought. Pakistan Journal of Botany 42: 2177-2189.
25. Hussain, S., Ali, A., Ibrahim, M., Saleem, M. F., Alias Haji, M. A., and Bukhsh, A. 2012. Exogenous application of abscisic acid for drought tolerance in sunflower (Helianthus annuus L.): A review. The Journal of Animal & Plant Sciences 22 (3): 806-826.
26. Igbal, N., Ashraf, M., and Ashraf, M. Y. 2009. Inﬂuence of Exogenous Glycine Betaine on Gas Exchange and Biomass Production in Sunﬂower (Helianthus annuus L.) under Water Limited Conditions. Journal of Agronomy and Crop Science 195: 420-426.
27. Igbal, N., Ashraf, M. Y., and Ashraf, M. 2011. Modulation of endogenous levels of some key organic metabolites by exogenous application of glycine betaine in drought stressed plants of sunﬂower (Helianthus annuus L.). Journal of Plant Growth Regulation 63: 7-12.
28. Jabbarzadeh, M., Tehranifar, A., Amiri, J., and Abedy, B. 2018. The effect of different concentrations of sodium nitroprusside (SNP) on some morphological, physiological and biochemical traits of Zinnia elegans under salinity stress. Journal of Plant Process and Function 6 (19): 105-116. (in Persian with English abstract).
29. Kostopoulou, P., Barbayiannis, N., and Noitsakis, B. 2010. Water relations of yellow sweet clover under the synergy of drought and selenium addition. Plant and Soil 330: 65-71.
30. Kuznetsov, V. V., Kholodova, V. P., Kuznetsov, V. V., and Yagodin, B. A. 2003. Selenium regulates the water status of plants exposed to drought. Doklady Biological Sciences 90: 266-268.
31. Loutfy, N., El-Tayeb, M. A., Hassanen, M. A., Moustafa, M. F. M., Sakuma, Y., and Inouhe, M. 2012. Changes in the water status and osmotic solute contents in response to drought and salicylic acid treatments in four different cultivars of wheat (Triticum aestivum). Journal of Plant Research 125: 173-184.
32. Makela, P., Jokinen, K., Kontturi, M., Peltonen-Sainio, P., Pheu, E., and Somersalo, S. 1998. Foliar application of glycinebetaine a novel product form sugar beet as an approach to increase tomato yield. Industrial Crops and Products 7: 139-148.
33. Mata, C., and Lamattina, L. 2001. Nitric oxide induces stomatal closure and enhances the plant adaptive responses against drought stress. Plant Physiology 126: 1196-1204.
34. Mehrpouyan, M. 2011. Study on CO2 exchange, photosynthesis and grain yield in sunflower cultivars under drought stress conditions. Journal of Crop Production Research (Environmental Stresses in Plant Sciences) 3 (2): 197-206. (in Persian with English abstract).
35. Rezaee Rad, H., Hooshmand, A. R., Naseri, A. A., and Siahpoosh, M. R. 2016. Effects of drought stress on physiological characteristics and yield of maize in the presence of a shallow water table in Ahvaz climatic conditions. Journal of Irrigation Science and Engineering 39 (1): 55-66. (in Persian with English abstract).
36. Rock, C. D., and Quatrano, R. S. 1995. Plant Hormones: Physiology, Biochemistry and Molecular Biology, Dordrecht, the Netherlands: Kluwer Academic Publishers, Second edition. 671 pp.
37. Rouhi, A., and Siosemardeh, A. 2008. Study of gas exchange in different wheat genotypes (Triticum aestivum L.) under drought stress. Seed and Plant Production Journal 24 (1): 45-62. (in Persian with English abstract).
38. Schurr, U., Gollan, T., and Schulze, E. D. 1992. Stomatal response to drying soil in relation to changes in xylem sap composition of sunflower, II. Stomatal sensitivity to abscisic acid imported from the xylem sap. Plant, Cell and Environment 15: 561-567.
39. Siddique, M. R. B., Hamid, A., and Islam, S. 1999. Drought stress effect on photosynthetic rate and leaf gas exchange of wheat. Botanical Bulletin- Academia Sinica Taipei 40: 141-145.
40. Siddique M. R. B., Hamid, A., and Islam, S. 2001. Drought stress effects on water relations of wheat. Botanical Bulletin- Academia Sinica Taipei 41: 35-39.
41. Singh, B., and Usha, K. 2003. Salicylic acid induced physiological and biochemical changes in wheat seedlings under water stress. Plant Growth Regulators 39: 137-141.
42. Siosemardeh, A., Ahmadi, A., Poustini, K., and Ebrahimzadeh, H. 2003. Stomatal and nonstomatal limitations to photosynthesis and their relationship with drought resistance in wheat cultivars. Iranian Journal of Agricultural Science 35 (1): 93-106. (in Persian with English abstract).
43. Siosemardeh, A., Ranjbar-balkhkanlou, H., Sohrabi, Y., and Bahram nejad, Y. 2011. Evaluation of grain yield, gas exchange and source and sink limitation in sunflower under drought stress at different levels of defoliation. Iranian Journal of Field Crop Science 42 (3): 585-596. (in Persian with English abstract).
44. Unyayar, S., Keles, Y., and Unal, E. 2004. Proline and ABA Levels in two sunflower genotypes subjected to water stress. Bulgarian Journal of Plant Physiology 30 (3-4): 34-37.
45. Wieczorek, J. F., Milczarek, G., Arasimovicz, M., and Ciszewski, A. 2006. Do nitric oxide donors mimic endogenous NO-related response in plants? Planta 224: 1363-1372.
46. Yao, X., Chu, J., and Wang, G. 2009. Effects of selenium on wheat seedlings under drought stress. Biological Trace Element Research 130: 283-290.
47. Yarnia, M., Safaie, P., Khorshidi-benam, M. B., and Farajzadeh, E. 2009. Effect of drought stress and potassium sulfate on yield and yield components of sunflower. New Finding in Agriculture, Islamic Azad University, Arak Branch. 3 (3): 317-332. (in Persian with English abstract).
48. Yordanov, I., Velikova, V., and Tsonev, T. 2003. Plant response to drought and stress tolerance. Bulgarian Journal of Plant Physiology. (Special Issue). 187-206.
49. Yousefvand, P., Sajedi, N., and Mirzakhani, M. 2011. Effect of drought stress, zeolite and selenium on yield and yield components on sunflower. New Finding in Agriculture, Islamic Azad University, Arak Branch. 5 (3): 325-339. (in Persian with English abstract).