Seed Aging: Chromosome Stability and Extended Viability of Seeds Stored Fully Imbided

Abstract

MATERIALS AND METHODS"Seeds" (fruits) of Lactuca sativa L. vars. Arctic King and Grand Rapids were obtained from Suttons Seeds Ltd., Reading, U. K. Batches of these seeds were placed in closed containers with separate vessels of sulfuric acid, water, or diluted sulphuric acid giving relative humidities of 0, 25, 50, 75, and 100% at 20 C in the container atmospheres (9). After 2 weeks, the moisture contents of the seed batches were determined, and the seeds were sealed into separate glass bottles. Other large batches of seeds from the same provenances were imbibed on moist filter papers in Petri dishes. These Petri dishes, together with the bottles of air-dry seeds, were placed in dark incubators maintained continuously at 30 C (Arctic King), and 25 C (Grand Rapids), in order to prevent germination of the imbibed batches of seeds.Fruits of Fraxinus americana L. were purchased from Vilmorin-Andrieux of Paris. Samples were brought to a range of moisture contents as described for the lettuce seeds. They were then sealed into bottles, and stored in the dark at 22 C. A large sample of fruits was imbibed by mixing with moist sand and stored at 22 C in the dark in order to prevent germination of the imbibed fruits (unpublished results).At the times stated in the results, seeds from these treatments were tested for germination under 40-w fluorescent daylight lamps at 22 C. Petri dishes of seeds which had been maintained continuously imbibed were simply brought out from the dark incubators, while samples of seeds from air-dry store were imbibed on moist filter papers in Petri dishes at the beginning of each germination test. Germination was scored as the emergence and geotropic curvature of the radicle.Chromosomes in 1-mm radicle tips of lettuce were ex-875 www.plantphysiol.org on May 12, 2018 -Published by Downloaded from

Seed moisture content during chilling and heat stress effects after chilling on the germination of common alder and downy birch seeds

“…Seed vigour measures the potential for rapid, uniform seed germination under a wide range of field conditions (Bray 1997). Seeds deteriorate more rapidly at high MC levels and high temperatures than at lower levels (McDonald 1999), leading to genetic and structural damage (Villiers 1974). The vigour of seeds can be assessed using a variety of methods, including physiological and biochemical tests.…”

Assessment of Seed Viability and Vigour in Neem (Azadirachta indica A. Juss.)

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Yellow bristle grass (Setaria pumila) germination biology

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