The Effect of Seed Health of Perennial Ryegrass (Lolium Perenne L.) on Germination Capacity

Abstract

The analysis of seed health and germination capacity of 7 varieties of Lolium perenne, originated from two breeding station and two seed company localized in different places of Poland, harvested in 2006, 2007 and 2008 were performed. Results of mentioned analysis indicated that seeds were contaminated by numerous species of fungi. The most numerous group of fungi were saprophytes or weak parasites such as: Alternaria alternata, Epicoccum nigrum, Septonema chaetospira and Penicillium spp. Pathogenic species were represented by species of Drechslera, Fusarium, Phoma, Curvularia lunata and Bipolaris sorokiniana. Seed germination capacity was influenced by contamination of fungi. It was found that seed more often contaminated by fungi germinated much poorer then seed with lower infection.

Seed Shattering: A Trait of Evolutionary Importance in Plants

“…A model of seed shattering in monocot or fruit dehiscence in dicot is presented in Figure 1. In monocots, seed shattering is triggered by the formation of an abscission layer at the attachment point between the lemma and pedicel by cell wall thickening and lignification (Harlan and DeWet, 1965;Elgersma et al, 1988;Fuller and Allaby, 2009). Swelling and dissolving of the middle lamella between adjacent cell walls in the abscission layer allows for grain release (Htun et al, 2014).…”

“…Examination of the spikelet bases between domesticated rice and the wild shattering types revealed that domesticated spikelet bases are characterized by a dimpled appearance and possess less symmetrical scars, whereas the wild types had a smooth scar with a straight profile at the spikelet bases (Li et al, 2006;Fuller et al, 2009). In Lolium spp., the abscission layer is present at the attachment point of lemma and palea to the rachilla (Elgersma et al, 1988). The abscission layer is easily identifiable as the cells present in it are smaller than the parenchymatous cells in the rachilla.…”

“…The abscission layer is easily identifiable as the cells present in it are smaller than the parenchymatous cells in the rachilla. In perennial ryegrass (Lolium perenne L.), this layer usually consists of 4-8 cell layers (Elgersma et al, 1988). In bahiagrass (Paspalum notatum Fluegge), cells in the abscission layer were larger, more prominent and present in five to seven layers.…”

“…For example, Burton et al (2017) indicated that seed shattering is less in early maturing crops. Elgersma et al (1988) reported that crops with erect growth habit are prone to shedding seeds prior to harvest, because in a crop with prostrate growth habit, the seed heads are somewhat protected against wind. Plant morphological characteristics such as vascular structure, pod structure or vascular bundle size can influence seed shattering (Summers et al, 2003).…”