Induction changes of the chlorophyll fluorescence in the apple trees leaves affectioned by powdery mildew
Induction changes of the chlorophyll fluorescence in the apple (Malus domestica Borkh.) trees leaves affectioned by powdery mildew (Podosphaera leucotricha Salm.) / Makovkin I.M., Kytayev O.I. // Sadivnytstvo (Horticulture). Ц 2015. Ц 69. Ц P. 177-183. Ц Refs.: 6. Ц in Ukrainian.
The changes of the photosynthetic processes in the apple trees leaves affectioned by powdery mildew have been researched by means of the chlorophyll fluorescence induction. The influence of this disease depression of the plant has been characterized. The affection degree increase has appeared to cause changes in the effectivity of the reactionary centres of the photosystem 2 functioning. The plateau coefficient which characterizes the relative amount of inactive reactionary centres increases, the efficiency of the photochemical processes which take place in darkness reduces. At the same time if the leaf affection gets stronger the Fv/Fp index that characterizes the photoenergetic adapttivity rises by 10-11%.
Key words: leaf, chlorophyll fluorescence induction, powdery mildew, apple, point of defeat.