Factors Affecting Storage of Yellow Globe Danvers Onion: Abscisic Acid During Maturation and Storage And Phenolic Substance Inhibitory to Botrytis allii and Botrytis cinerea
Danai Boonyakiat
Thesis of Master of Sicence in Horticulture, Oregon State Univerity, Graduate School, United States Of America. 1981.
1981.
บทคัดย่อ
Factors Affecting Storage of Yellow Globe Danvers Onion: Abscisic Acid During Maturation and Storage And Phenolic Substance Inhibitory to Botrytis allii and Botrytis cinerea
Free adscisic acid (ABA) in Yellow Globe Danvers onion tissues was determined during maturation and storage. The amount of ABA in leaf tissue reached a maximum (1.81 ng/gm dry weight) at 40%top fall. Neck tissue ABA reached a maximum (0.33 ng/gm dry weight) at 60-70% top fall. ABA of bulb tissue slightly increased during maturation, then declined and remined steady (0.21 ng/gm dry weight) during storage with a slight increase again after 5 month storage. Bulb tissue ABA decreased when onion bulbs began to sprout. Some preliminary data indicates that bulb ABA concentration may be positively related to respiration rate. A study of phenolic constituents in bulb inner and dry outer scales, found that major phenolics are quercetin 0 and 26, 750
mg/gm dry weight; chlorogenic acid 416.7 and 937.5
mg/gm dry weight; catechin 458.3 and 812.5
mg/gm dry weight; catechol 41.7 and 312.5
mg/gm dry weight ; caffeic acid 141.7 and 62.5
mg/gm dry weight ; and arbutin trace and absent in inner scale outer scale, respectively.
Mycelial growth and spore germination of B. allii and B. cinerea were inhibited by catechol concentration above 50 ug/1. The mechanism of inhibition appears to be different in the two species of Botrytis.
Preliminary study on bulb weight loss at 3 different storage temperatures : 0°, 10° and 20 °C showed that weight loss was 3,5 and 10%, respectively, after 6 months storage. onions with dry outer scales removed developed new dry outer scales in 4 weeks at room temperature, and room temperature with air circulation.