Seedling Emergence and Growth of Solid Matrix Primed Kentucky Bluegrass Seed

Abstract

Seed priming is effective in reducing the time required for germination and emergence, and for increasing final germination and/or emergence especially under sub‐optimal conditions. This study was conducted to determine whether advanced emergence due to solid matrix priming (SMP) is followed by advanced seedling growth of Kentucky bluegrass (KBG) (Poa pratensis L.) under sub‐optimal conditions (15/5°C). Coleoptile, the second and third leaf emergence, and seedling size 28 d after emergence were examined in four cultivars, which differed in their seed sizes. Distributions of coleoptile emergence over time were significantly affected by SMP, and seedlings from SMP seed emerged more rapidly and uniformly in three cultivars. Moreover, the number of days required for 50% emergence (T50) was shortened by 5 to 14 d. In contrast, the rate of second and third leaf emergence and seedling size 28 d after emergence did not differ between seedlings emerged from unprimed and SMP seed, indicating that the vegetative growth is basically determined genetically. However, SMP could subsequently enhance the mean seedling size of a population by increasing the number of seedlings that emerged rapidly. The SMP treatments could provide practical benefits on stand establishment of KBG under sub‐optimal temperatures by enhancing the mean seeding size but not by increasing the growth rate of individual seedlings.