Proboscis curling in a pollinator causes extensive pollen movement and loss

Knowledge of pollen movement and frequency of interspecific hybridization in fragmented populations of rare species is a prerequisite for the implementation of conservation measures. In a large-scale study area (14,000 hectares) we analysed 297 Malus sylvestris trees with nine nuclear microsatellite markers. After open pollination of 564 offspring from 51 mother trees located in seven harvesting sites were investigated and genetic paternity analysis was performed. The paternal parent was identified for 213 offspring and the pollen dispersal distances between mother and pollen source were calculated. A large proportion of detected pollination events (42.4%) were observed within a radius of 50 m of the mother tree. The comparison of different tree densities indicated that with decreasing density the pollen dispersal distances increase. We observed pollination over long distances with a maximum of 10.7 km which is probably one of the reasons for a low spatial genetic structure within the M. sylvestris population and a stable genetic diversity in the offspring. Incorporating microsatellite data of 21 apple cultivars, a hybridization frequency of nearly 8% was determined. With decreasing tree density the number of hybridization events increased. Based on the results of our study an enhancement of the density of existing M. sylvestris populations is recommend to reduce the likelihood of hybridization. The production of young plants originated from seeds collected after open pollination is not advisable. Instead of that the seedlings for further reintroduction measures should be produced by controlled crossings in seed orchards to ensure ‘true type’ M. sylvestris individuals.

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Pollen movement by the bat Artibeus jamaicensis (Chiroptera) in an agricultural landscape in the Yucatan Peninsula, Mexico

Mammal Research ◽

10.1007/s13364-016-0306-9 ◽

2017 ◽

Vol 62 (2) ◽

pp. 189-193 ◽

Cited By ~ 2

Author(s):

M. Cristina MacSwiney G. ◽

Beatríz Bolívar-Cimé ◽

Rita Alfaro-Bates ◽

J. Javier Ortíz-Díaz ◽

Frank M. Clarke ◽

...

Keyword(s):

Agricultural Landscape ◽

Yucatan Peninsula ◽

Artibeus Jamaicensis ◽

Yucatán Peninsula ◽

Pollen Movement

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Corrigendum to: Wild seedlings of a tree endemic on granite outcrops show no evidence of inbreeding depression

Australian Journal of Botany ◽

10.1071/bt17175_co ◽

2019 ◽

Vol 67 (8) ◽

pp. 649

Author(s):

Nicole Bezemer

Keyword(s):

Population Genetic ◽

Nature Reserve ◽

Allelic Diversity ◽

Parentage Analysis ◽

Floristic Diversity ◽

Survey Period ◽

Dispersal Patterns ◽

Genetic Structuring ◽

Granite Outcrops ◽

Pollen Movement

Plant communities on granite outcrops are characterised by high biodiversity and endemism, and strong population genetic structuring. The floristic diversity and structure of inselberg flora receives much attention in international conservation research, yet our understanding of how recruitment influences population genetic structure of plants endemic to granite outcrops is limited. To determine the immediate genetic consequences of recruitment and to quantify mating and dispersal patterns by parentage analysis, I conducted an opportunistic study following a wildfire in a stand of the lignotuberous tree Eucalyptus caesia Benth. (Myrtaceae) at Boyagin Nature Reserve. The entire adult stand (n=180) plus seedlings (n=115) were genotyped with 14 microsatellite loci. Compared with adults, seedlings had low heterozygosity and a high inbreeding co-efficient, but similar levels of allelic diversity. There was no evidence of post-germination selection against homozygous seedlings over the 20 month survey period. Seedlings that resulted from cross-pollination were more heterozygous than seedlings resulting from selfing, but could not be distinguished based on height measurements or survivorship. Parentage analysis in CERVUS revealed mostly limited seed dispersal, assuming that candidate parents closest to seedlings were the maternal parent. By comparison, pollen movement was more extensive, yet still restricted to plants within the stand. Recruitment has increased the population size, but appears insufficient to enhance genetic diversity in the Boyagin stand of E. caesia. Nonetheless, E. caesia appears adept at persisting as extremely small populations.

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Tracking Papaya Pollen Movement with the GUS Transgene Marker

HortScience ◽

10.21273/hortsci.40.4.1094d ◽

2005 ◽

Vol 40 (4) ◽

pp. 1094D-1094 ◽

Cited By ~ 1

Author(s):

Richard M. Manshardt ◽

Cathy Mello ◽

Sharon D. Lum ◽

Leanne Ta

Keyword(s):

Colorimetric Assay ◽

Gus Expression ◽

Genetically Engineered ◽

Separate Study ◽

Organic Farm ◽

Weak Negative Correlation ◽

Low Levels ◽

The Impact ◽

Pollen Movement ◽

Gus Assays

Genetically engineered (GE), virus-resistant papaya cultivars in Hawaii are easily identified by a colorimetric assay for the β-glucuronidase (GUS) marker transgene. We used GUS to track pollen movement from a central 1-acre plot of gynodioecious GE `Rainbow' plants into seeds on surrounding border rows of non-GE `Sunrise' papaya. GUS evidence of cross-pollination occurred in 70% of female plants (43% of assayed seeds), compared with only 13% of the predominantly self-pollinating hermaphrodite plants (7% of seeds) segregating in the gynodioecious `Sunrise' border rows. The percentage of GUS+ seeds in border row plants showed a weak negative correlation (r = –0.32) with distance from the nearest GE tree (30 m maximum). In a non-GE papaya field located less than a mile downwind from the `Rainbow' source, no evidence of GUS was found in 1000 assayed seeds. In a separate study, the origin of GUS+ seed discovered in papaya fruits from an organic farm was investigated. Leaf GUS assays revealed that 70% of trees were GE, indicating that the grower had planted GE seed. The impact of pollen drift from GE trees in the same field was determined by screening seed samples from 20 non-GE hermaphrodites for GUS expression. Only three hermaphrodites (15%) showed GUS+ seeds, at low levels ranging from 3% to 6% of contaminated samples. These data indicate that the major source of GE contamination in organic fields is seeds of unverified origin, rather than pollen drift from neighboring GE fields. Organic growers are advised to: 1) plant only seed that is known to be non-GE, preferably obtained by manual self-pollination of selected non-GE hermaphrodites; 2) avoid open-pollinated seed; and 3) grow only hermaphrodite (self-pollinating) trees, removing any female or male plants from production fields.

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