Abscission and seed shattering in perennial ryegrass (Lolium perenneL.)

✍ Scribed by A. Elgersma; J. E. Leeuwangh; H. J. Wilms

• Publisher: Springer
• Year: 1988
• Tongue: English
• Weight: 572 KB
• Volume: 39
• Category: Article
• ISSN: 0014-2336
• DOI: 10.1007/bf00043367

✦ Synopsis

Yield in grass seed crops is decreased by seed shattering, which is generally caused by abscission . Abscission layer development in perennial ryegrass, Lolium perenne L., was investigated to determine its histogenesis in relation to the morphological stages of the inflorescence . Spikelets were fixed with weekly intervals from heading to harvest ripeness . Florets were dissected and microtome sectioned .

Abscission layers were located in the rachilla just below each floret . They were already present at the heading stage . Only slight histological changes were observed in the cells of the abscission layers during flowering and seed development . Breaking of the abscission layers occurred four to five weeks after anthesis, starting at the epidermis . No degradation of the abscission layer cells was detected, indicating that abscission took place mechanically . No histological differences in abscission mechanism were found between groups of genotypes with contrasting seed retention, suggesting that in our material differences in seed retention were probably caused by morphological factors other than abscission layer development . Selection for high seed retention is briefly discussed .