Cleistogamy is a type of automatic self-pollination of certain plants that can propagate by using non-opening,

self-pollinating Self-pollination is a form of pollination in which pollen from the same plant arrives at the stigma of a flower (in flowering plants) or at the ovule (in gymnosperms). There are two types of self-pollination: in autogamy, pollen is transferr ...

flowers. Especially well known in

peanut The peanut (''Arachis hypogaea''), also known as the groundnut, goober (US), pindar (US) or monkey nut (UK), is a legume crop grown mainly for its edible seeds. It is widely grown in the tropics and subtropics, important to both small an ...

pea The pea is most commonly the small spherical seed or the seed-pod of the flowering plant species ''Pisum sativum''. Each pod contains several peas, which can be green or yellow. Botanically, pea pods are fruit, since they contain seeds and d ...

s, and

pansies The garden pansy (''Viola'' × ''wittrockiana'') is a type of large-flowered hybrid plant cultivated as a garden flower. It is derived by hybridization from several species in the section ''Melanium'' ("the pansies") of the genus ''Viola'', p ...

, this behavior is most widespread in the grass family. However, the largest genus of cleistogamous plants is ''

Viola ; german: Bratsche , alt=Viola shown from the front and the side , image=Bratsche.jpg , caption= , background=string , hornbostel_sachs=321.322-71 , hornbostel_sachs_desc=Composite chordophone sounded by a bow , range= , related= *Violin family ...

''. The more common opposite of cleistogamy, or "closed marriage", is called

chasmogamy Chasmogamy, is a plant reproductive mechanism in which pollination occurs in chasmogamous flowers. Chasmogamous flowers are commonly showy with open petals encircling exposed reproductive parts. Chasmogamous stems from Greek for "open marriage", na ...

, or "open marriage". Virtually all plants that produce cleistogamous flowers also produce chasmogamous ones.Meeuse, Bastiaan and Sean Morris. 1984. The sex life of flowers. New York, NY: Facts on File Publishers. pp 110-111. The principal advantage of cleistogamy is that it requires fewer plant resources to produce seeds than does chasmogamy, because development of petals, nectar and large amounts of pollen is not required. This efficiency makes cleistogamy particularly useful for seed production on unfavorable sites or adverse conditions. ''

Impatiens capensis ''Impatiens capensis'', the orange jewelweed, common jewelweed, spotted jewelweed, jewelweed, spotted touch-me-not, or orange balsam, is an annual plant in the family Balsaminaceae that is native to North America. It is common in bottomland so ...

,'' for example, has been observed to produce only cleistogamous flowers after being severely damaged by grazing and to maintain populations on unfavorable sites with only cleistogamous flowers. The obvious disadvantage of cleistogamy is that

self-fertilization Autogamy, or self-fertilization, refers to the fusion of two gametes that come from one individual. Autogamy is predominantly observed in the form of self-pollination, a reproductive mechanism employed by many flowering plants. However, species ...

occurs, which may suppress the creation of genetically superior plants. Another disadvantage of self-fertilization is that it leads to the expression in progeny of deleterious recessive

mutation In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA. Mutations result from errors during DNA or viral replication, m ...

s. For genetically modified (GM)

rapeseed Rapeseed (''Brassica napus ''subsp.'' napus''), also known as rape, or oilseed rape, is a bright-yellow flowering member of the family Brassicaceae (mustard or cabbage family), cultivated mainly for its oil-rich seed, which naturally contains a ...

, researchers hoping to minimise the admixture of GM and non-GM crops are attempting to use cleistogamy to prevent

gene flow In population genetics, gene flow (also known as gene migration or geneflow and allele flow) is the transfer of genetic material from one population to another. If the rate of gene flow is high enough, then two populations will have equivalent a ...

. However, preliminary results from

Co-Extra Co-Extra was an EU-funded research programme on ''co-ex''istence and ''tra''ceability of genetically modified crops and their edible derivatives that ran from 2005-2009. It was granted €13.5 million under the Sixth Framework Programme of the E ...

, a current project within the EU research program, show that although cleistogamy reduces gene flow, it is not at the moment a consistently reliable tool for

biocontainment One use of the concept of biocontainment is related to laboratory biosafety and pertains to microbiology laboratories in which the physical containment of pathogenic organisms or agents ( bacteria, viruses, and toxins) is required, usually ...

; due to a certain instability of the cleistogamous trait, some flowers may open and release genetically modified pollen.

References

{{reflist Plant reproduction Pollination Plant sexuality

See also

References