title: Effect of phytohormones on pectate lyase activity in ripening Musa acuminata.
abstract: A differential activity peak of pectate lyase (PEL) was observed during ripening of banana fruits (Musa acuminata Harichhal) receiving different hormone treatments. Exposure of fruits to 25 ppm ethylene for 24 h, as well as dipping of M. acuminata fruits in 1 mM 2,4-dichlorophenoxy acetic acid (2,4-D) for 4 h, hastened fruit ripening. Both PEL activity peak and climacteric peak were observed on the 4th and 10th days of treatment with ethylene and 2,4-D, respectively, compared to the 16th day in control fruits. Gibberellic acid (GA) treatment retarded fruit ripening and both PEL activity and climacteric peaks were observed on the 19th day. Treatment of fruits with ethylene or 2,4-D also advanced the appearance of a polygalacturonase (PG) peak and GA delayed its appearance, but the activity peaks always appeared in post-climacteric fruits, in contrast to PEL activity peaks coinciding with the respiratory peaks.
authors.affiliation: Department of Biochemistry, University of Lucknow, Lucknow 226 007, India.
authors.forename: Anurag
authors.initials: A
authors.lastname: Payasi
authors.forename: P C
authors.initials: PC
authors.lastname: Misra
authors.forename: G G
authors.initials: GG
authors.lastname: Sanwal
mesh_terms: D015084:2,4-Dichlorophenoxyacetic Acid / Q000494:pharmacology*; D019069:Cell Respiration / Q000187:drug effects / Q000502:physiology; D004789:Enzyme Activation / Q000187:drug effects; D005030:Ethylenes / Q000494:pharmacology*; D005875:Gibberellins / Q000494:pharmacology*; D028521:Musa / Q000187:drug effects / Q000201:enzymology* / Q000254:growth & development; D011096:Polygalacturonase / Q000378:metabolism; D011133:Polysaccharide-Lyases / Q000378:metabolism*
chemical_list: D005030:Ethylenes; D005875:Gibberellins; D015084:2,4-Dichlorophenoxyacetic Acid; C036216:ethylene; C007842:gibberellic acid; D011096:Polygalacturonase; D011133:Polysaccharide-Lyases; C023911:pectate lyase