Plum Polystigmosis (Plum Leaf Blotch): Development Characteristics and Struggling Measures

Abstract

The life cycle development of “Polystigma rubrum” fungus has been investigated and the infection rate of different varieties of plums and cherry plums (myrobalan plum) with plum leaf blotch (Polystigmosis) has been identified. High infection rate has been registered in the cherry plum variety of Gogcha and plum variety of Persikovaya, while in the plum varieties of Renclod Green and Renclod Althan it was relatively lower. The experiments have shown that spraying with 3 %
Bordeaux solution in the autumn season, as well as collection and elimination of plant residues after defoliation minimize the overwintering inoculum of the pathogen. The recommended triple spraying scheme (Score + Copper oxychloride.2; Chorus + Taspa.2) provides high biological efficiency reducing the disease by 92.6 %-96.4%.