Changes in growth, chlorophyll content and peroxidase and alpha-amylase activities in sunflower calli after UV-C irradiation

• Type: Article in International Scientific Journal
• Date: 1999

Authors

Conde, P (Author) Other; Sousa, A (Author) Other; Santos, S (Author) Other; Dos Santos, CV (Author) Other; Caldeira, G (Author) Other

Journal

The Journal is awaiting validation by the Administrative Services.

Title: BELGIAN JOURNAL OF BOTANY

Vol. 132

Pages: 35-42

ISSN: 0037-9557

Indexing

ISI Web of Knowledge - 2 Citations

Scopus - 2 Citations

Other information

Authenticus ID: P-001-5CX

Abstract (EN): Sunflower (Helianthus annuus L. cv. Girapac SH222) calli were induced and grown on modified MURASHIGE & SKOOG (1962) medium. Two-month-old calli were exposed for 15 minutes to four UV-C radiation treatments : one irradiance of 3.170 mW.cm(-2) for one day (treatment T1); one irradiance of 3.170 mW.cm-2 every day for seven days (treatment T2); one irradiance of 5.350 mW.cm(-2) for one day (treatment T3) and one irradiance of 5.350 mW.cm(-2) for seven days (treatment T4). Control calli were maintained under white light conditions (treatment T0). Eight-day-old sunflower plants, grown under greenhouse conditions, were also exposed to UV-C radiation (T1 and T2). Irradiated calli soon became dark and with necrotic areas, but they were more tolerant to UV irradiation than plants, since they could sustain growth. Ca2+ and K+ contents were not significantly affected in irradiated calli cells. On a calli fresh weight basis, T1 and T2 treatments resulted in a significant increase of soluble protein levels. Calli cells from UV treatments suffered a significant reduction in guaiacol peroxidase activity and an increase in alpha-amylase activity. In control calli alpha-amylase activity decreased with time. The present study shows that sunflower calli are more tolerant to UV rays than plants, and demonstrates interactions between UV-C radiation and peroxidase and alpha-amylase activities.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 8