Role of Lipoxygenase During Flower Bud Opening in Roses (Rosa hybrida L.)

• Published in: Journal of the Korean Society for Horticultural Science Vol. 49; no. 3
• Main Authors: Kumar, Naveen (Indian Agricultural Research Institute, New Delhi, India), Srivastava, Girish Chand (Indian Agricultural Research Institute, New Delhi, India), Dixit, Kiran (Choudhary Charan Singh Harayana Agricultural University, Hissar, India), E-mail: dixit2000in@yahoo.com
• Format: Journal Article
• Language: English
• Published: 01.06.2008
• Subjects: membrane stability; ROSA; ROSA (GENERO)
• ISSN: 0253-6498

The adverse effect of lipid peroxidation during flower bud opening in roses was investigated. Experiments were conducted from 2005 to 2007 on two cultivars of cut-roses (Rosa hybrida L.), 'Grand Gala' and 'First Red' obtained from a commercial grower. Flower stems were harvested at different developmental stages. Petals were separated from seven different petal whorls in flowers (outermost to innermost) of 'Grand Gala' and 'First Red' at all developmental stages. During the first three stages of flower bud development (S1 - S3) petal membrane remained stable for a considerable period of time. However, at subsequent stages (S4 - S6) membrane leakage increased considerably in both cultivars showing membrane stability index of 48 percent and 38 percent in flower petals of 'First Red' and 'Grand Gala' respectively. TBARS (Thiobarbiturate reactive substances) content was very low during the first two stages of flower bud development; thereafter, a steep rise was noted in different petal whorls of both cultivars. Lipoxygenase activity showed a progressive rise from stage 1 to stage 6 of flower bud development. Differential LOX (Lipoxygenase) activity was noticed during flower bud opening, a progressive rise during the first three phases, but at a slower pace and a two-fold rise at later stages of development.