Prevalence and control of guava fruit anthracnose

Abstract

The prevalence of guava (Psidium guajava L.) fruit anthracnose was surveyed in three major guava‐producing areas of Bangladesh during 1987 and 1988. One hundred percent of plants and 90–100% of fruits were severely diseased. Disease severity was higher in 1987 than in 1988. Pestalotiopsis psidii Pat., Colletotrichum gloeosporioides Penz. and Botryodiplodia theobromae Pat. were established as causal organisms. In in vitro tests Topsin M, Rovral wp and Rovral FLO completely inhibited mycelial growth of three fungi, while Dithane M‐45 and Macuprax proved ineffective. When applied on plants, Topsin M significantly reduced fruit infection and disease severity (89.5%) followed by Rovral FLO (87.0%), Rovral wp (80.0%) and Dithane M‐45 (73.0%) over control. The use of a sticker and increasing the number of sprays from four to seven resulted in significantly greater reduction of fruit infection.

Key words:

• Guava
• fruit anthracnose
• temperature
• humidity
• Rovral