Tytuł pozycji:
First report of twig blight of ban tulsi (Croton bonplandianus Bail.) caused by Choanephora cucurbitarum (Berk.and Ravenel) Thaxt. in India
In August 2015, twig blight disease of ban tulsi (Croton bonplandianus Bail.) caused by
Choanephora cucurbitarum (Berk. & Ravenel) Thaxt. was observed for the first time, in the
Gangetic alluvial region of West Bengal, India. A severe disease incidence (40–50%) showed
twig blight symptoms starting with shoot apical meristem (SAM), leaf, and blossom blight
symptoms. Typical symptoms were characterized by over-projecting black pin head like
emerging sporangiola which formed mycelial cushion on the infected surface. The present
report describes the identification of the causal pathogen as C. cucurbitarum based on its
morphology and the internal transcribed spacer of its ribosomal DNA (rDNA – ITS) sequences
with 100% identity of NCBI-GenBank published Choanephora database. Optimum
temperatures, 28–30°C, coupled with high relative humidity (80–90%) during the monsoon
season enhances the disease’s progress. To the best of our knowledge this is the first report of
twig blight of C. bonplandianus, caused by C. cucurbitarum, in India as well as globally.