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单词 self-pollination
释义

self-pollination


self-pol·li·na·tion

(sĕlf′pŏl′ə-nā′shən)n.1. The transfer of pollen from an anther to a stigma of the same flower; autogamy.2. The transfer of pollen from an anther of one flower to a stigma of another flower on the same plant; geitonogamy.
self′-pol′li·nate′ v.

self-pollination

n (Botany) the transfer of pollen from the anthers to the stigma of the same flower or of another flower on the same plant. Compare cross-pollination ˌself-ˈpolliˌnated adj

self′-pollina′tion



n. the transfer of pollen from the anther to the stigma of the same flower, another flower on the same plant, or the flower of a plant of the same clone. Compare cross-pollination.
Thesaurus
Noun1.self-pollination - fertilization by transfer of pollen from the anthers to the stigma of the same flowerpollenation, pollination - transfer of pollen from the anther to the stigma of a plantcleistogamy - the production of small nonopening self-pollinating flowerscross-pollination - fertilization by transfer of pollen from the anthers of one flower to the stigma of another
Translations

self-pollination


self-pollination

the transfer of pollen from the anthers to the stigma of the same flower or of another flower on the same plant

Self-Pollination

 

the transfer of pollen from the stamen of a flower to the stigma of the same flower (autogamy) or to the stigma of another flower of the same plant (geitonogamy). According to their capacity for self-pollination, plants are distinguished as those that are self-fertile and those that are self-sterile. Self-fertile plants, which include oats, peas, and barley, produce normal seeds through self-pollination. Self-pollination generally occurs in the flower bud, whereas “alien” pollen, which may play a subsequent role in fertilization, usually falls on the stigma of an already opened flower. Self-pollination occurs rarely in wild plants; it occurs in cultivated plants considerably more often. However, even in self-fertile plants, self-pollination apparently leads to gradual degeneration of varieties, and periodic intravarietal cross-pollination is conducted to increase viability.

Self-sterile plants that have been self-pollinated either do not produce seeds or produce underdeveloped seeds from which stunted plants develop. Self-sterility may be explained by self-incompatibility, that is, the inability of male and female sex cells descended from a single flower to merge and form an embryo. In cross-pollinators, self-incompatibility is controlled by special genes that inhibit growth of the pollen tubule on its own stigma or along the column of the pistil or, finally, inhibit the merging of sex cells and development of the embryo. Fundamental to these processes is the apparent capacity of the plants to elaborate substances similar to antibodies that inhibit the development of pollen on their own stigma. The manifestation of genes of incompatibility is strongly influenced by external conditions, which may partially or completely suppress their effects. The degree of self-incompatibility is usually not identical in different individuals of the same variety or species. Nor is it the same during the different periods of flowering, thereby making it possible to overcome self-incompatibility in selection work. I. V. Michurin used a number of artificial methods in his experiments.

In many plants, self-pollination occurs at the end of the flowering period, serving as a “reserve” phenomenon in the event that normal cross-pollination has not occurred. To ensure self-fertilization, plants have elaborated special adaptations—for example, changes in the position of the flower and the turning of the stigmas toward the stamens or of the stamens toward the stigmas.

REFERENCES

Darwin, C. Deistvie perekrestnogo opyleniia i samoopyleniia ν rastitel’nom mire. Moscow-Leningrad, 1939.
Lobashov, M. E. Genetika, 2nd ed. Leningrad, 1967.
Pervukhina, N. V. Problemy morfologii i biologii tsvetka. Leningrad, 1970.
Kugler, H. Blütenökologie, 2nd ed. Jena, 1970.

V.N. VEKHOV

self-pollination

[¦self ‚päl·ə¦nā·shən] (botany) Transfer of pollen from the anther to the stigma of the same flower or of another flower on the same plant.

self-pollination


Self-incompatibilityFig. 279 Self-incompatibility . The process depicted results in the progeny being S 1 /S3 and S2 /S3.

self-pollination

the transfer of pollen from the stamen of a flower either to the stigma of the same flower or to another flower on the same plant. Since self-pollination leads to self-fertilization which is a form of inbreeding, many plants have developed mechanisms to prevent its occurrence. For example, plants can be DIOECIOUS, show SELF-INCOMPATIBILITY, and have differential maturation times of male and female floral organs on the same plants (for example, see ARUM LILY). Compare CROSS-POLLINATION.

self-pollination


Related to self-pollination: cross-pollination
  • noun

Antonyms for self-pollination

noun fertilization by transfer of pollen from the anthers to the stigma of the same flower

Related Words

  • pollenation
  • pollination
  • cleistogamy

Antonyms

  • cross-pollination
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