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The embryonic plant stem above the cotyledons.



the part of the stem in a plant seedling between the cotyledons and the first true leaves (the first internode). In embryos the epicotyl is a conoid outgrowth consisting of primary formative tissue, or meristem. In plants with aboveground shoot formation the epicotyl and the cotyledons appear above the surface of the soil (for example, in beans and melons). In plants having underground shoot development the cotyledons remain in the soil, and the epicotyl is bent into a loop and then straightened; it carries the bud with the first leaves to the surface, toward the light (for example, in peas, plums, and oaks).

References in periodicals archive ?
Based on the aforementioned considerations and the fact that there are few studies in the literature involving the estimation of genetic parameters, the determination of the optimum sample size and the conversion of quantitative data in multiple categories of the lengths of the hypocotyl and epicotyl in soybean genotypes, the need to study the genotypes of soybeans to elucidate these topics is evident.
The genotypes used for experiments 1, 3 and 4 were grown in pots containing 3 dm3 of soil with 1/3 organic matter;for each genotype, five plants were assessed with regard to the length of the hypocotyl at the V2 stage (FEHR; CAVINESS, 1977) and the length of the epicotyl at the V3 stage (FEHR; CAVINESS, 1977).
Posteriorly, the data were analyzed for variability in the lengths of the hypocotyl and epicotyl in each experiment, adopting a fixed statistical model.
Although it would be interesting to evaluate the plants directly in each class, because this work can be considered an initial effort in categorizing the lengths of the hypocotyl and epicotyl, in 3 and 5 classes, it was necessary to first measure the plants and then categorize them.
01) by the F test for the lengths of the hypocotyl and epicotyl in the four experiments (Table 1), indicating the existence of genetic variability among the genotypes, which enables success when selecting promising materials.
During germination the stem axis below the apical meristem does not elongate and therefore there is no epicotyl as stated by Rao (1971).
Weak magnetic fields decrease genome activity before proliferation [6], change plant ontogeny [12], configuration of epicotyl of Triticum aestivum L.
Purification and properties of amine oxidase from epicotyls of Pisum sativum.
Effect of ethylene treatment on polar IAA transport, net 1AA uptake and specific binding of N-l-naphthylphthalamic acid in tissues and microsomes isolated from etiolated pea epicotyls.
from zygotic embryos and from cotyledons and epicotyls of four- and