INFLORESCENCE STRUCTURE IN PRIMITIVE ANGIOSPERMS

A comprehensive taxonomic revision of the genus Notobubon (Apiaceae) is presented. Twelve woody evergreen species are recognised, all (with the exception of N. laevigatum) endemic to the Cape Floristic Region of South Africa. The taxonomy of these prominent, though poorly collected, species has until now been problematic. They are distinguished from one another by their habit (size and branching pattern), the overall shape, size, and colour of the ultimate leaflet segments, the inflorescence structure (peduncle length, number, and length of rays in the primary umbel), the fruit morphology (fruit size, presence or absence of wings), and the fruit anatomy (symmetry of the mericarps, presence or absence of additional rib vittae, size of commissural vittae). Species relationships are assessed in the form of a cladistic analysis of 26 morphological characters, resulting in a well-resolved phylogenetic hypothesis. A comprehensive key to the species, their correct nomenclature, and typification, together with descriptions and known geographical distribution for all the species are presented and illustrated.

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LATERAL FLORET 1 induced the three-florets spikelet in rice

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1700504114 ◽

2017 ◽

Vol 114 (37) ◽

pp. 9984-9989 ◽

Cited By ~ 24

Author(s):

Ting Zhang ◽

Yunfeng Li ◽

Ling Ma ◽

Xianchun Sang ◽

Yinghua Ling ◽

...

Keyword(s):

Leucine Zipper ◽

Molecular Mechanisms ◽

Ectopic Expression ◽

Target Sequence ◽

Class Iii ◽

Rice Mutant ◽

Inflorescence Structure ◽

Meristem Maintenance ◽

Floral Meristems ◽

Sterile Lemma

The spikelet is a unique inflorescence structure in grass. The molecular mechanisms behind the development and evolution of the spikelet are far from clear. In this study, a dominant rice mutant, lateral florets 1 (lf1), was characterized. In the lf1 spikelet, lateral floral meristems were promoted unexpectedly and could generally blossom into relatively normal florets. LF1 encoded a class III homeodomain-leucine zipper (HD-ZIP III) protein, and the site of mutation in lf1 was located in a putative miRNA165/166 target sequence. Ectopic expression of both LF1 and the meristem maintenance gene OSH1 was detected in the axil of the sterile lemma primordia of the lf1 spikelet. Furthermore, the promoter of OSH1 could be bound directly by LF1 protein. Collectively, these results indicate that the mutation of LF1 induces ectopic expression of OSH1, which results in the initiation of lateral meristems to generate lateral florets in the axil of the sterile lemma. This study thus offers strong evidence in support of the “three-florets spikelet” hypothesis in rice.

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Maesa brevipedicellata (Primulaceae), a new species from Papua New Guinea

Blumea - Biodiversity Evolution and Biogeography of Plants ◽

10.3767/blumea.2020.65.01.10 ◽

2020 ◽

Vol 65 (1) ◽

pp. 83-85

Author(s):

P. Sumanon ◽

W.L. Eiserhardt ◽

H. Balslev ◽

T.M.A. Utteridge

Keyword(s):

New Species ◽

Papua New Guinea ◽

New Guinea ◽

Herbarium Specimen ◽

Inflorescence Structure ◽

A New Species

Maesa brevipedicellata, a new species of Maesa ( Primulaceae-Maesoideae) from Papua New Guinea, is described and illustrated based on herbarium specimen observations. The collections of this species resemble M. rufovillosa and were previously determined as that species. Maesa brevipedicellata is unique with its self- supporting habit, hispid hairs throughout and paniculate inflorescences with very short pedicels. This new species mainly differs from M. rufovillosa by the habit (tree/shrub in M. brevipedicellata vs climber in M. rufovillosa) and the inflorescence structure (panicles in M. brevipedicellata vs simple racemes in M. rufovillosa).

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Inflorescence structure and control of flowering time and duration by light in buckwheat (Fagopyrum esculentum Moench)

Journal of Experimental Botany ◽

10.1093/jxb/erh164 ◽

2004 ◽

Vol 55 (402) ◽

pp. 1509-1517 ◽

Cited By ~ 31

Author(s):

M. Quinet ◽

V. Cawoy ◽

I. Lefevre ◽

F. Van Miegroet ◽

A.-L. Jacquemart ◽

...

Keyword(s):

Flowering Time ◽

Fagopyrum Esculentum ◽

Inflorescence Structure ◽

Fagopyrum Esculentum Moench ◽

And Control

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Gynomonoecy in Chenopodium quinoa (Chenopodiaceae): variation in inflorescence and floral types in some accessions

Biologia ◽

10.2478/s11756-007-0001-z ◽

2007 ◽

Vol 62 (1) ◽

Cited By ~ 9

Author(s):

Atul Bhargava ◽

Sudhir Shukla ◽

Deepak Ohri

Keyword(s):

Floral Morphology ◽

Chenopodium Quinoa ◽

Inflorescence Structure ◽

Female Flowers

AbstractInflorescence structure and floral morphology has been studied in 19 accessions of C. quinoa. All the accessions show gynomonoecy and bear three basic flower types viz. hermaphrodite, chlamydeous female and achlamydeous female and number of types can be extended to five considering the size of flowers. Ten types have been classified on the basis of the proportion of hermaphrodite and female flowers and their arrangement, depending upon the number of divisions of the dichasium on the glomerule. Implications of these results in facilitating intervarietal crosses are discussed.

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