Reproductive biology and genetic marker diversity in Grevillea infecunda (Proteaceae), a rare plant with no known seed production

2002 ◽  
Vol 15 (4) ◽  
pp. 485 ◽  
Author(s):  
Sarah K. Kimpton ◽  
Elizabeth A. James ◽  
Andrew N. Drinnan
Keyword(s):  
Reproductive Biology ◽  
Fragment Length Polymorphism ◽  
Pollen Viability ◽  
Genotypic Variation ◽  
Pollen Grains ◽  
Genotypic Diversity ◽  
Narrow Endemic ◽  
Root Suckering ◽  
Sufficient Variation ◽  
Two Populations

Grevillea infecunda D.J.McGillivray is a narrow endemic that reproduces vegetatively via root suckering. The reproductive biology of five Grevillea infecunda populations was investigated by scanning electron microscopy and light microscopy. Stigma maturation follows normal Grevillea development. However, a large number of pollen grains with aberrant forms were documented. A fluorochromatic reaction (FCR) test revealed 0.04% pollen viability. All pollen samples collected from two populations were completely sterile. All viable grains were >100 �m in diameter and included aberrant forms. Amplified fragment length polymorphism (AFLP) technique was used to investigate genotypic diversity in G. infecunda. Three primer pairs revealed sufficient variation in 109 loci to assign a unique phenotype to every individual (N = 40) sampled. This suggests that the populations were established from founder seedlings. The species has apparently lost the ability to reproduce sexually but genotypic variation is maintained through asexual reproduction via root suckers.

scholarly journals Population Structure of Fusarium fujikuroi from California Rice and Water Grass

2008 ◽  
Vol 98 (9) ◽  
pp. 992-998 ◽  
Author(s):  
L. L. A. Carter ◽  
J. F. Leslie ◽  
R. K. Webster
Keyword(s):  
Population Structure ◽  
Fragment Length Polymorphism ◽  
Genotypic Variation ◽  
Genotypic Diversity ◽  
Population Diversity ◽  
Fusarium Fujikuroi ◽  
Mating Types ◽  
Bakanae Disease ◽  
Barnyard Grass ◽  
Vegetative Compatibility Groups

The recent observance of Fusarium fujikuroi, the causal agent of Bakanae disease of rice, in California provides a unique opportunity to assess the population diversity of an introduced pathogen in a new environment. We collected 172 isolates of this pathogen between 2000 and 2003 from California rice and two from water grass (Echinochloa spp.). Pathogenicity of F. fujikuroi was demonstrated on early water grass (E. oryzoides) and barnyard grass (E. crus-galli) indicating that weed control should be part of Bakanae management programs. Both mating types and six unique amplified fragment length polymorphism haplotypes corresponding to six identified vegetative compatibility groups were detected. The two most frequently isolated haplotypes encompassed 94% of the collected isolates, suggesting that clonal reproduction dominates. Coefficients of similarity between the unique haplotypes ranged from 0.94 to 0.98, and indicate that there is very little genotypic variation in the F. fujikuroi population in California. The near fixation of the MAT-1 idiomorph (observed ratio 170 MAT-1:4 MAT-2), is consistent with a hypothesis of predominant or exclusive asexual reproduction. The low level of introduced genotypic diversity, in conjunction with the asexual reproductive strategy of this population will slow evolutionary processes, including adaptation to the California environment.

scholarly journals Reproductive biology and pollination of Cabomba aquatica (Cabombaceae)

Rodriguésia ◽  
2011 ◽  
Vol 62 (4) ◽  
pp. 919-926 ◽  
Author(s):  
Jacilene Bezerra da Silva ◽  
Ana Virgínia de Lima Leite
Keyword(s):  
Reproductive Biology ◽  
High Frequency ◽  
Pollen Viability ◽  
Pollen Grains ◽  
Pollen Flow ◽  
Northeastern Brazil ◽  
Nectar Production ◽  
High Pollen ◽  
Pollinator Behavior ◽  
Effective Pollinators

Abstract Reproductive biology and pollination of the fanwort, Cabomba aquatica Aubl., were studied in populations from dams located in Dois Irmãos State Park, Recife, Pernambuco state, northeastern Brazil. Flower anthesis in this species is diurnal and lasts two days. The flowers are bisexual and exhibit herkogamy and incomplete protogyny. Each flower produces an average of 2.1 ± 94.8 pollen grains, with a P/O ratio of 1.055 and high pollen viability (99.7%). This species is self-compatible, but requires biotic vectors to transfer pollen. We observed visits of bees (Apidae and Halictidae), wasps (Vespidae) and flies (Diptera) to the flowers. Bees and wasps were considered to be effective pollinators, both due to their behavior and their high frequency of visits to flowers, whereas flies were considered to be occasional pollinators. The floral mechanism (herkogamy and protogyny), together with low nectar production and pollinator behavior during visits, may contribute to increase pollen flow between individuals.

scholarly journals On the reproductive biology of Salacia fruticosa Wall. ex M.A. Lawson - an endemic medicinal plant of the Western Ghats, india

2018 ◽  
Vol 10 (15) ◽  
pp. 13002-13005
Author(s):  
K. Subin ◽  
P. A. Jose ◽  
T. V. Sarath
Keyword(s):  
Reproductive Biology ◽  
Fruit Set ◽  
Pollen Viability ◽  
Pollen Grains ◽  
Seedling Bank ◽  
The Poor ◽  
Short Period ◽  
Poor Seed ◽  
Endemic Medicinal Plant ◽  
The Western Ghats

Salacia fruticosa Wall. ex M.A. Lawson, an endemic species was studied for the reproductive biology as this species showed reduced fruit set and natural regeneration.  The stigma-anther proximity, an extremely low number of pollen grains, a short period of pollen viability, a sparse incidence of pollinators, protandrous and facultative autogamous nature of the flowers and a low percent in fruit set were identified as biological constraints for the species.  The incidence of seed pest was added to the poor seed and seedling bank and accelerated rarity process of the species.

scholarly journals Cytogenetics and Reproductive Biology of some BELE (Abelmoschus manihot Linn., Medic Sub-Species manihot) Cultivars

2002 ◽  
Vol 20 (1) ◽  
pp. 4 ◽  
Author(s):  
Anand P. Tyagi
Keyword(s):  
Papua New Guinea ◽  
Reproductive Biology ◽  
Genetic Difference ◽  
Pollen Viability ◽  
Pollen Grains ◽  
New Guinea ◽  
Staining Technique ◽  
Root Tips ◽  
Fiji Islands ◽  
Cross Compatibility

Four locally grown (from Fiji Islands) and three imported (from Papua New Guinea), a total of seven BELE (Abelmoschus manihot Linn., Medic sub-species manihot) cultivars were investigated for their cytogenetics and reproductive biology. Chromosome counting from flower buds and root tips showed that chromosome number in all the seven cultivars does not exceed 2n=66. Pollen viability in all the seven cultivars was high, exceeding 85% from pollen staining technique and 78% from pollen germination technique. All the seven Bele cultivars were fully self-compatible. Cross-compatibility among four local cultivars and three cultivars from Papua New Guinea was very high. However cross compatibility between local (Fijian) cultivars and cultivars from Papua New Guinea was partial indicating some degree of genetic difference between cultivars from two countries. This could be due to differences in compatibility alleles between cultivars from Fiji and Papua New Guinea. Procedures such as cutting the style shorter and placing pollen grains to enhance and affect fertilisation to get cross seed were suggested.

scholarly journals A Duplicated Copy of the Meiotic Gene ZIP4 Preserves up to 50% Pollen Viability and Grain Number in Polyploid Wheat

Biology ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 290
Author(s):  
Abdul Kader Alabdullah ◽  
Graham Moore ◽  
Azahara C. Martín
Keyword(s):  
Pollen Viability ◽  
Pollen Grains ◽  
Wheat Chromosome ◽  
Grain Number ◽  
Meiotic Gene ◽  
Chromosome 5B ◽  
Mutant Pollen ◽  
Female Gametogenesis ◽  
Chromosome 3B

Although most flowering plants are polyploid, little is known of how the meiotic process evolves after polyploidisation to stabilise and preserve fertility. On wheat polyploidisation, the major meiotic gene ZIP4 on chromosome 3B duplicated onto 5B and diverged (TaZIP4-B2). TaZIP4-B2 was recently shown to promote homologous pairing, synapsis and crossover, and suppress homoeologous crossover. We therefore suspected that these meiotic stabilising effects could be important for preserving wheat fertility. A CRISPR Tazip4-B2 mutant was exploited to assess the contribution of the 5B duplicated ZIP4 copy in maintaining pollen viability and grain setting. Analysis demonstrated abnormalities in 56% of meiocytes in the Tazip4-B2 mutant, with micronuclei in 50% of tetrads, reduced size in 48% of pollen grains and a near 50% reduction in grain number. Further studies showed that most of the reduced grain number occurred when Tazip4-B2 mutant plants were pollinated with the less viable Tazip4-B2 mutant pollen rather than with wild type pollen, suggesting that the stabilising effect of TaZIP4-B2 on meiosis has a greater consequence in subsequent male, rather than female gametogenesis. These studies reveal the extraordinary value of the wheat chromosome 5B TaZIP4-B2 duplication to agriculture and human nutrition. Future studies should further investigate the role of TaZIP4-B2 on female fertility and assess whether different TaZIP4-B2 alleles exhibit variable effects on meiotic stabilisation and/or resistance to temperature change.

Inflorescence development and seed production in Lolium spp. × Festuca pratensis tetraploid hybrids

1975 ◽  
Vol 85 (2) ◽  
pp. 301-307 ◽  
Author(s):  
P. Cremades ◽  
E. W. Bean
Keyword(s):  
Seed Production ◽  
Lolium Perenne ◽  
Lolium Multiflorum ◽  
Pollen Viability ◽  
Festuca Pratensis ◽  
Inflorescence Development ◽  
Tetraploid Hybrid ◽  
Pollen Release ◽  
Sufficient Variation ◽  
Reproductive Characters

SUMMARYThe reproductive development and seed production characters of a Lolium multiflorum × Festuca pratensis tetraploid hybrid and a Lolium perenne × Festuca pratensis tetraploid hybrid were compared with those of their tetraploid parental cultivars. Experiments were carried out under glasshouse and natural conditions; single plants were studied as only small quantities of seed were available from the breeder. The lowtemperature/short-day requirements for inflorescence induction of the two hybrids were in between those of the corresponding parental species. The variance of the date at which vegetative primordia changed to the reproductive condition was greater in the hybrids than in the parental cultivars, but the variance of the dates of inflorescence emergence were similar for the hybrids and parental cultivars. Inflorescences ranged from the Lolium type with only sessile spikelets to the Festuca type with primary branches. Inner glumes, which are absent in the Lolium parents but present in Festuca pratensis, were found in the hybrids, though not in all spikelets. In the Lolium perenne × Festuca pratensis hybrid pollen release, potential pollen viability and floret fertility were low, but the Lolium multiflorum × Festuca pratensis hybrid produced large amounts of pollen with a higher potential viability and had floret fertilities similar to those of its two parental cultivars. There was sufficient variation in reproductive characters for further selection, particularly in the Lolium perenne × Festuca pratensis hybrid.

The relationship of reproductive biology to the rarity of endemic Aster curtus (Asteraceae)

1999 ◽  
Vol 77 (1) ◽  
pp. 140-149 ◽  
Author(s):  
David E Giblin ◽  
Clement W Hamilton
Keyword(s):  
Pacific Northwest ◽  
Reproductive Biology ◽  
Fluorescent Microscopy ◽  
Pollen Grains ◽  
Field Trials ◽  
Rare Plants ◽  
Glacial Outwash ◽  
Compatible Cross ◽  
Species Rarity ◽  
Filled Seeds

The fecundity of rare plants is a commonly used indicator of performance at the population or species level. However, accurately interpreting reproductive output requires an understanding of a particular species's breeding system. The purpose of this study was to determine if reproductive biology contributes to the restricted distribution of Aster curtus Cronq. We hypothesized that (i) A. curtus, like many Asteraceae species, is self-incompatible, and (ii) that pollinations between patches produce significantly more filled seeds than pollinations within patches. Fluorescent microscopy of pistils harvested after greenhouse pollination showed A. curtus to be partially self-compatible. Cross-pollination resulted in significantly more pollen grains per stigma and significantly greater pollen germination than self-pollination. Similarly, field pollination trials showed that between-patch crosses produced significantly more filled seeds than within-patch crosses. Nevertheless, within-patch pollinations produced substantial levels of filled seed. Results from the greenhouse and field trials suggest that the reproductive biology of A. curtus contributes little to its rarity. Understanding why A. curtus is rare has important implications to the conservation of the glacial outwash prairie. Moreover, the data from this research can be used in further developing predictive models for plant species rarity based on reproductive biology.Key words: Aster, endemic, Pacific Northwest, rarity, reproductive biology, self-incompatibility.

scholarly journals Phenology, reproductive biology and growing degree days of the grapevine ‘Isabel’ (Vitis labrusca, Vitaceae) cultivated in northeastern Brazil

2016 ◽  
Vol 76 (4) ◽  
pp. 975-982 ◽  
Author(s):  
N. A. S. Nunes ◽  
A. V. Leite ◽  
C. C. Castro
Keyword(s):  
Reproductive Biology ◽  
Pollen Viability ◽  
Floral Biology ◽  
Climatic Conditions ◽  
Northeastern Brazil ◽  
Growing Degree Days ◽  
Base Temperature ◽  
Vitis Labrusca ◽  
Degree Days ◽  
Inflorescence Development

Abstract Phenology and reproductive biology of cultivated species are important for the comprehension of the requirements for fruit and seed production and the management of pollinators. This study aimed to characterise the phenology, reproductive biology and growing degree days of the grapevine ‘Isabel’ (Vitis labrusca) in northeastern Brazil during January 2011 (P1), Augst 2011 (P2), April 2012 (P3) and August 2012 (P4). We recorded the duration (days) of the phenological stages, pruning (P), woolly bud (W), budburst (B), inflorescence development (ID), flowering (F), ripening (R) and harvest (H). We analysed the floral biology, the sexual system and the breeding system. We measured the growing degree days (GDD) required to reach the subperiods P-B, B-F and F-H. The periods P1, P2, P3 and P4 lasted for 116, 125, 117 and 130 days, respectively. The number of days of harvest were similar in the same dry (P1 and P3) and rainy (P2 and P4) periods. All the periods that we recorded were shorter than those observed in other regions of Brazil, which may be attributable to the mean temperature and carbohydrate metabolism. The flowers are green, hermaphroditic, with an odour of mignonette, low pollen viability and autogamous. The base temperature of 10°C was considered the most adequate for the subperiods as has been documented for other grape varieties in Brazil. Thus, temperature was also the most adequate for the cycles, presenting a smaller standard deviation (0.119, 0.147, 0.156 and 0.153 to P1, P2, P3 and P4, respectively) when compared to a base temperature of 12°C (0.122, 0.158, 0.165 and 0.160 to P1, P2, P3 and P4, respectively). The higher and the lower observed GDD were 1972.17 and 1870.05, respectively, both above the values recorded in other parts of Brazil for same variety. The phonological results, including knowledge of growing degree days, are important to the planning of cultures at the study site and in other regions that have similar climatic conditions and make it possible to pre-determine the harvest.

scholarly journals Genotypic diversity between surgical and nasal Staphylococcus aureus isolates

2020 ◽  
Author(s):  
Dongzhu Ma ◽  
Patrick L. Maher ◽  
Kimberly M. Brothers ◽  
Nathan J. Phillips ◽  
Deborah Simonetti ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Joint Infection ◽  
Parallel Evolution ◽  
Genotypic Diversity ◽  
Nasal Carriage ◽  
Host Immune System ◽  
Host Status ◽  
Fibronectin Binding ◽  
Two Populations ◽  
Atypical Strains

AbstractStaphylococcus aureus is a common organism in periprosthetic joint infection (PJI). Little is known about S. aureus genetic diversity in PJI as compared to nasal carriage. We hypothesized PJI S. aureus strains would be associated with increased virulence as compared to those from nasal carriage. Whole genome sequencing and multilocus sequence typing (MLST) was performed to genotype these two populations at high resolution. MLST revealed a variety of genotypes in both populations but many belonged to the most common clonal complexes. In nasal cultures, 69% of strains were of clonal complexes CC5, CC8, and CC30. In PJI cultures, only 51% could be classified in these common clonal complexes. Remaining strains were atypical, and these atypical strains in PJI were associated with poor host status and compromised immune conditions. Mutations in genes involved in fibronectin binding (ebh, fnbA, clfA, clfB) systematically distinguished later PJI isolates from the first PJI isolate from each patient. S. aureus isolated from nasal carriage and PJI specimens differ significantly, with the latter being more diverse. Strains associated with lower pathogenicity tended to be found in immunocompromised patients, suggesting the host immune system plays an important role in preventing PJI. Repeated mutations in S. aureus genes associated with extracellular matrix binding were identified suggesting an adaptive, parallel evolution in S. aureus during the development of PJI.

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