Enhancement of freezing tolerance of olive leaves by foliar application of methyl jasmonate and 24–epibrassinolide through changes in some metabolites and antioxidant activity

Effect of Chemical, Bio-Fertilizers and Jasmonic Acid and Their Interaction on the Quantitative, Qualitative Characteristics of Olive Fruits Olea europaea L. Cultivar Surani

“…Increase in the quality characteristics of the fruits by increasing the levels of spraying with jasmonic acid is only a result of the role of jasmonic in most physiological processes and their regulation, as it acts as an antioxidant and maintains the health of fruits from damage and the increase of chemical compounds and pigments such as anthocyanins, flavonoids, phenolic acids and various proteins that improve the quality of fruits through Inhibiting the attack of insects and the growth of fungi on trees and fruits through their interaction with calcium and ethylene, which gives strength and hardness to the fruits and this is what we obtained in our study, where the pulp thickness,fruit weight and percentage of soluble solids increased [10,25].…”

“…The moral superiority in the following traits (tree yield, fruit weight, fruit volume , and pulp thickness) of olive fruits shown in tables (1,2,3,4) is only a result of the role played by chemical fertilizer consisting of zinc and boron in maintaining plant growth And its activity through its effect on the physiological functions of trees, especially the photosynthesis process, which stimulates the plant to absorb water and nutrients that plant needs to perform its vital processes and give direct signals to build specific hormones to perform certain functions of plant, such as the florigen hormone for flowers, which accelerates the maturation of tissues and internal cells and thus pushes Trees lead to the formation of flowers, the building of various compounds and proteins, the activation of cofactors for enzymes and hormones in building cell walls, the transfer of sugars, absorption of macro and micro nutrients , the collection of various amino acids within plant tissues, and the increase in the rate of fruit set , thus increasing the yield of trees [21][22][23].Or, it may be due to the role of chemical fertilizer in the ripening and homogeneity of fruits through its effect on improving the vegetative characteristics of trees such as the number of branches, leaf area, chlorophyll and carbohydrates ratio, which led to an increase in plant activity and physiological processes, and this made it reflected positively on the qualitative and quantitative characteristics of the fruits [24,25].…”

“…Or perhaps the moral superiority in tree yield, T.S.S and fruit oile percentage shown in tables (1,5,6) is due to jasmonic acid and its great role in increasing the accumulation of fatty acids, terpenes and oils in fruits as well as stimulating enzymes that increase the plant's resistance to conditions Inappropriate by strengthening cell walls and preventing the decomposition of cellulose bonds, which gave strength and durability to trees and fruits against mechanical injuries, and a number of antioxidant enzymes and stresses such as (SOD, CAT and PPO) are activated, which control the production of ethylene and the accumulation of fatty acids, and jasmonic works on Increasing the level of proline acid in fruits and thus maintaining the health of trees and the continuation of their physiological activity and the necessary vital processes for the formation of fruits and their various chemical compounds [17,25].These results are in line with the findings of a number of researchers on different types of fruit trees [10,25,28].…”

Cold Stress, Freezing Adaptation, Varietal Susceptibility of Olea europaea L.: A Review

“…Furthermore, the plants treated with SA (1.0 mM) showed a significantly lower ion leakage and MDA content [ 173 ]. Jasmonates (lipid-derived phytohormones,) and Brassinosteroids (steroid hormones) are novel phytohormones involved in plant developmental processes and plant adaptations to biotic and abiotic stresses [ 176 , 177 ]. Three different concentrations of methyl jasmonate (MeJA; 0.02, 0.1, 0.2 mM) and of 24–epibrassinolide (EBR; 0.2, 0.4, and 0.6 μM) respectively, were used to monitor the response to low temperatures in Koroneki cultivar [ 174 ].…”

Effect of methyl jasmonate and GA3 on canola (Brassica napus L.) growth, antioxidants activity, and nutrient concentration cultivated in salt-affected soils

“…JA, a lipid-derived hormone, regulates various biological processes and is crucial for plant responses to salinity [ 23 ]. It influences protein patterns in wounded leaves and enhances plant antioxidant activity [ 24 ].…”