Seed Weight and Germination Time Affect Growth of 2 Shrubs

Abstract

The objective of this study was to investigate relationships between seed size, time of germination, and seedling growth in winterfat (Cerutoides lanata (Pursh) J. T. Howell) and silver sagebrush (Artenzisia cuna Pursh). Individual seeds of winterfat were placed into 6 weight classes ranging from 1.5-2.0 to Z-4.0 mg seed-l while silver sagebrush seeds were separated into 7 classes ranging from 0.53 to 0.83 mg seed-l. Seeds were incubated at U°C, seedlings with radicles < 3.0 mm were removed at 1, 2,3, 4-5 and 6-12 day intervals, grown 5 days in darkness at 18oC, and axial length measured. Total germination of winterfat increased 5.5% mg-l increase in seed weight, but germination rate was similar among weight classes, averaging 53.1% day-l. Seed weight and time of germination interactively influenced growth of winterfat seedlings. Seedling length of winterfat was more than 2-fold greater in the > 4.0 than the 1.5-2.0 mg seed-l class while lengths of seedlings in the > 2.0-2.5 through > 3.5 to 4.0 mg seed-l weight classes were intermediate. Seedling length decreased 0.9 to 3.3 mm for each day that germination was delayed from 1 to 12 days with the least and greatest reductions occurring for lightest and medium weight seeds, respectively. Total germination for silver sagebrush initially increased with seed Fight, but declined at weights greater than about 0.57 mg seed-; germination rate was similar (57.1% day-l) among weight classes. Seedling length of silver sagebrush increased 0.3 mm mg-l increase in seed weight whereas length decreased curvilinearly as time to germination was delayed. When winterfat is used for restoration, relatively heavy seeds should be used because they have the greatest germination and produce large seedlings. Because seedling length of silver sagebrush increased with increasing seed weight it is also desirable to select heavier seeds; however, reduced germination in heavier seeds may necessitate increasing seeding rates.

Nitrogen addition increases sexual reproduction and improves seedling growth in the perennial rhizomatous grass Leymus chinensis

“…This increase in resources can speed up seed germination because the radicle can break the seed coat faster, speeding up the nutrient absorption from the soil, and hence seedling growth [26][27][28]. This faster seedling establishment is an advantage for new stand establishment because earlier developing seedlings can obtain more resources, thereby gaining a competitive advantage to later germinating seeds [29,30]. We also found a significant difference in seed germination success and rate among our three sampling years.…”

“…L. chinensis, a perennial, rhizomatous grass widely distributed in the eastern regions of the Eurasian steppe zone [30]. L. chinensis is tolerant to saline-alkali soil, extreme drought and cold, and has high palatability for livestock likes cow and sheep [31].…”

Establishing winterfat in prairie restorations in Saskatchewan

“…Booth and Morgan (1993) and Hou and Romo (1998a) indicated that seedlings developing from early-germinating diaspores might have greater survival because they produce more vigorous seedlings than late germinating ones. Late emerging seedlings of winterfat establish poorly under drought stress compared with seedlings emerging early (Waddington and Shoop 1995).…”

Technical Note: Early harvest of squirreltail seed

“…In both 1995 and 1996, weight of seeds became significantly heavier for seeds collected later in the growing season (Table 2). Heavier seeds within a seed lot have been shown to exhibit higher germination amounts and better seedling emergence characteristics than lighter seeds (Aiken and Springer 1995, Limbach and Call 1996, Hou and Romo 1998. Seeds collected later in the process of seed head maturation also exhibit greater seed germination amounts (Phaneendranath et al 1978).…”