Effect of light and temperature on the germination of lettuce seeds.
Summary of "Effect of light and temperature on the germination of lettuce seeds."
A short period (15-30 min) at 30° C promotes germination of seeds of Lactuca sativa L. cv. Repolhuda in darkness. Far-red light reverses this stimulation, and the escape curves for phytochrome and high-temperature action are quite similar, indicating that the two factors act at a common point in the chain of events leading to germination. It is suggested that high temperature acts by decreasing the threshold of the active, far-red absorbing, form of phytochrome (Pfr) needed to promote germination.
Departamento de Bioquímica, Universidade Federal de Permambuco, 50. 000, Recife, PE, Brasil.
This article was published in the following journal.
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Medical and Biotech [MESH] Definitions
The initial stages of the growth of SEEDS into a SEEDLING. The embryonic shoot (plumule) and embryonic PLANT ROOTS (radicle) emerge and grow upwards and downwards respectively. Food reserves for germination come from endosperm tissue within the seed and/or from the seed leaves (COTYLEDON). (Concise Dictionary of Biology, 1990)
Very young plant after GERMINATION of SEEDS.
A thioredoxin subtype that is ubiquitously found in the plant kingdom. It reduces a variety of seed storage proteins and may play a role in the germination process of seeds.
Emission of LIGHT by a substance as its temperature is raised. It is sometimes called hot light in contrast to LUMINESCENCE.
A part of the embryo in a seed plant. The number of cotyledons is an important feature in classifying plants. In seeds without an endosperm, they store food which is used in germination. In some plants, they emerge above the soil surface and become the first photosynthetic leaves. (From Concise Dictionary of Biology, 1990)