การเกิดโรคใบจุดของเปล้าน้อย (Croton sublyratus Kurz.) โดย Glomerella cingulata และผลกระทบต่อปริมาณสารเปลาโนทอลในใบ

• Main Author: ธนาสาร ขาวสอาด
• Other Authors: นลิน นิลอุบล
• Format: Theses and Dissertations
• Language: Thai
• Published: จุฬาลงกรณ์มหาวิทยาลัย 1999
• Subjects: เปลาโนทอล; โรคใบจุด; เปล้าน้อย (พืช); Glomerella cingulata
• Online Access: https://digiverse.chula.ac.th/Info/item/dc:36088
• Institution: Chulalongkorn University

Pathogenic fungus causing leave - spot disease of Plau - Noi (Croton sublyratus Kurz.) was isolated from the Play - Noi leaves collected from Prachaub Khirikhan province. It was similar to Glomerella cingulata. When cultivated on Czapek s agar with 12 - h illumination, it gave best spore formation. When G. cingulata was inoculated to Plau - Noi leaves, the percentage of infected area was varied in correlation with spore density used for infection. The highest spore density tested of 10° spores / ml caused 15.64 % infected area on the leaf per one tip. After inoculation and observation of attacking the leaf surface with spores by scanning electron microsope, the spore germination and the formation of appressorium occurred at 48 hr. The infected leaves were classified according to their severity into 6 groups. Determination of plaunotol from the infected leaves of all groups in comparison with that of the normal leaves from Plau - Noi IBGE 2 showed that there were no significant differences among all groups including the normal