Temperature requirements for seed germination and seedling growth of Zostera marina from central Japan

Abstract

The optimal water temperature in seed germination and the upper critical water temperature in seedling growth were determined for Zostera marina collected from Ise Bay, Japan. The relationship between the seed germination rates and seed storage period (0, 30 and 60 days at 0°C) was also examined. The optimal water temperature for seed germination was in the range from 10 to 15°C regardless of the storage periods, in which germination rates ranged from 35 to 57%. Seedlings grown from seed up to 10 cm in total length were cultured for 1 week under various water temperatures to measure their relative growth rates. The optimal water temperature in growth was in the range from 20 to 25°C; relative growth rates ranged from 2.0 to 2.6%. Seedlings could survive up to a water temperature of 28°C, but most seedlings withered at 29 or 30°C. The optimal water temperatures for seed germination and seedling growth were related to the seasonal changes of water temperature at the sampling site. Although seedlings were rarely observed in the field in summer, they can grow at temperatures as high as 28°C. Therefore, Z. marina may extend its distribution as far as where the summer water temperature is lower than 28°C.

Eelgrass survival in two contrasting systems: role of turbidity and summer water temperatures

“…obs.). Z. marina can become stressed at 25°C (Rasmussen 1977), and an upper limit range from 28 to 30°C has been proposed as a critical threshold for growth (Evans et al 1986, Orth & Moore 1986, Abe et al 2008. Temperatures exceeding 30°C for prolonged periods have been associated with large-scale declines and transplant failures in the Chesapeake Bay (Moore & Jarvis 2008, Golden et al 2010, Jarvis & Moore 2010, Tanner et al 2010) as well as in laboratory studies (Pulido & Borum 2010, Staehr & Borum 2011.…”

Temperature characteristics in seed germination and growth of Zostera japonica Ascherson & Graebner from Ago Bay, Mie Prefecture, central Japan

“…Therefore, it is expected that Z. japonica endures higher water temperature than Z. marina. In our previous report [18], we showed that the temperature characteristics of seedlings and determined the upper critical water temperature of Z. marina to be 28°C based on culture experiments under strictly controlled water temperature conditions [18]. However, we have no comparable data on the temperature characteristics on Z. japonica.…”

“…However, we have no comparable data on the temperature characteristics on Z. japonica. In the present study, we determined the temperature characteristics for seed germination and growth in Z. japonica by using the same experimental design as adopted by Abe et al [18] for Z. marina, and discuss the possibility of potential expansion in the geographical distribution using the results.…”

“…Among the various environmental factors, water temperature is one of the most important factors that determine the seasonal growth and the distributional patterns of marine plants [17][18][19]. There are several reports that the maximum biomass of Zostera japonica population appeared during summer [4,[11][12][13][14][15]20], whereas that of Z. marina population appeared during spring [21][22][23][24][25][26].…”

Influence of temperature and salinity on germination of eelgrass (Zostera marina L.) seeds

“…It is also a key component of eelgrass bed reconstruction methodology. Temperature and salinity play important roles in eelgrass seed germination (Orth and Moore, 1983;Conacher et al, 1994;Abe et al, 2008;Tanner and Parham, 2010). In this study, the germination rates of eelgrass seeds at different combinations of temperature and salinity were compared in order to lay the groundwork for establishing an eelgrass artificial seedling culture method.…”