III. Change in chlorophyll and anthocyanin content
Published online by Cambridge University Press: 27 March 2009
1. Floret samples of S321 perennial rye-grass (Lolium perenne L.), S215 meadow fescue (Festuca pratensis L.) and S352 timothy (Phleum pratense L.) were taken at 3-day intervals from inflorescence emergence to seed harvest. These were analysed for total chlorophyll content, chlorophyll a: chlorophyll b ratio and total anthocyanin content.
2. All varieties showed qualitatively similar patterns of total chlorophyll content. At emergence chlorophyll first increased on exposure to light and then fell as anther formation progressed. After fertilization a rapid increase in floret chlorophyll content coincided with early seed formation due to pigmentation of the expanding seed epidermis. Polymerization of carbohydrates to form endosperm starch resulting in increasing dry-matter content caused a concomitant fall in total chlorophyll when assessed on this basis. The final stages of seed maturation were accompanied by a further gradual decline to a very low level.