THE EFFECTS OF APPLYING CHITOSAN OF DIFFERENT MOLECULAR WEIGHTS ON THE GROWTH AND QUALITY OF KAMCHATKA BERRIES (LONICERA CAERULEA L.): PART 1

Kamchatka berries contain many valuable organic and mineral compounds. However, the ripe berries are not very firm and have low transport resistance. We aimed to study the effect of chitosan solutions of different molecular weights on the growth, yield, and quality of Kamchatka berries. Chitosan with lower molecular weights, 3 and 12 kDa, stimulated plant growth, while those with molecular weights above 50 kDa reduced plant growth compared with control shrubs. Chitosan 125 and 500 kDa increased Kamchatka berry yield. In addition, chitosan 125 kDa increased fruit weight throughout the yield period. Fruit sprayed with chitosan 3, 5, and 50 kDa were dark in colour at harvest. Chitosan 3, 5, 12, and 50 kDa increased fruit/skin resistance to mechanical damage. Finally, chitosan 3, 5, 50, and 950 kDa increased average fruit firmness. Overall, we recommend higher molecular weight chitosan to increase yield and lower molecular weight chitosan to increase firmness and resistance to damage.