Physiological and biochemical changes associated with flower development and senescence in Dianthus chinensis L

Abstract

Flowers of Dianthus chinensis growing in Kashmir University Botanic Garden (KUBG) were selected for the present study. Flower development and senescence was divided into six stages (I–VI), categorized as (I) tight bud stage, (II) mature bud stage, (III) paint brush stage, (IV) fully open/bloom stage, (V) partially senescent stage and (VI) senescent stage. Various physiological and biochemical changes associated with flower development and senescence were recorded. Fresh and dry mass, water content and flower diameter showed a continuous increase from bud to bloom, i.e., from stage I–IV and a significant decrease from stage V to VI. Scanning electron microscopic studies showed a clear degeneration of the cellular integrity and architecture with the onset of senescence in Dianthus chinensis. Soluble proteins, α-amino acids and sugar fractions increased with flower opening and showed a decrease as the senescence progressed. SDS-PAGE of the petal tissues revealed a decrease in both high and low molecular weight proteins. The present study suggests that the protein degradation is the key factor in regulating the process of flower senescence in this flower.