To study the remobilization rate affected by growth regulators in wheat a field experiment was carried out in the south of Iran over 2017-2019 with a split-split plot design and three iterations in completely randomized blocks. The main plots were two irrigation regimes (full irrigation and irrigation interruption at the grain-filling stage), two wheat cultivars (Chamran 2 and Durum Karkheh cv.s) were as sub plots, and four growth regulators (control (no growth regulator), salicylic acid, jasmonic acid, and cytokinin) placed in sub-sub plots. Results revealed the significant impact of the triple interaction on grain yield. The highest grain yield (4803 kg/Ha) was observed for Chamran 2 cv. treated with complete irrigation and salicylic acid. Although grain yield declined by 15.5% in the Karkheh cv. with irrigation interruption at the grain-filling stage and non-administration of growth regulators, treatment with salicylic acid managed to attenuate the adverse impact of drought stress in grain yield. The highest current photosynthesis and its contribution were observed in cultivars treated with complete irrigation. Moreover, irrigation regimen and growth regulators each had significant impacts on proline, catalase enzyme, and stomatal conductance. Overall, results suggested that using salicylic acid in Chamran 2 cv. would be advisable to increase growth and grain yield and reduce decline under stress.

Relevance. One of the most important factors which can influence on the growth and development of strawberries is the negative temperature in winter and especially in its snowless period. We were interested to study special aspects of the oxidative stress, accumulation of protector’s conjunctions, antioxidant and water status in autumn period of varieties strawberry garden different ecologicalgeographical origin in the conditions of the Orel region.Methods. The objects of the research were the leaves of Fragaria ananassa of different ecological and geographical origin in autumn period: Tsaritsa, Alba, Sara, Korona, Kokinskaya Rannya, Solovushka, Urozhainaya TsGL.Results. As the result was shown that in autumn period, when plants began preprocessing for winter, strawberry varieties Solovushka, Tsaritsa, Sara and Korona have been marked by increased antioxidant activity (for example, the enzymes SOD and catalase), little formation of reactive oxygen species and, in the end, low structural and functional damage to cell membranes. Also it was shown an increase in bound and a decrease in free water in the leaves of plants when the temperature decreased. At the same time, in the end of autumn, on the background of high content of free proline (19.38-29.73 mg/kg) and sucrose (2.65-6.46 mg/g), the varieties Solovushka, Tsaritsa, Sara and Korona had the highest ratio of bound/free water (4.10-8.10) in comparison with the with Urozhainaya TsGL and Alba. Thus, the varieties Solovushka, Tsaritsa, Sara and Korona are characterized by high adaptability to the winter conditions in the Orel region.