Dataset Information

The patterns of inbreeding depression in food-deceptive Dactylorhiza orchids.

ABSTRACT:

Introduction

Inbreeding depression (ID) in food-deceptive plants have been reported previously, however, it has not been often proven that selfed seeds germinate better than outbred ones or that selfing affects ID. To resolved these issues, food-deceptive related Dactylorhiza majalis, D. incarnata var. incarnata and D. fuchsii orchids were investigated.

Methods

Hand pollination treatments and control pollination were conducted. Fruit set, number of seeds per fruit, seed length, number of well-developed seeds per fruit, and proportion of in vitro asymbiotic germination seeds, were analyzed in relation to inflorescence levels and used as fitness indicators for these orchids. The ID and pollen limitation were measured.

Results

The lowest ID (δ = -1.000) was in D. majalis, and present in combination with a high pollen limitation in its populations. D. fuchsii showed higher ID (δ = 0.366), and D. incarnata var. incarnata weak ID (δ = 0.065), although ID varied between its fitness components. The seed number per fruit differed significantly between the treatments and the inflorescence levels in treatments.

Discussion

This study emphasizes that the breeding system rather than the flower position on the inflorescence shaped the quality and quantity of reproductive output. The ID and its effect on germination of food-deceptive orchid seeds undoubtedly played an important role.

SUBMITTER: Wroblewska A

PROVIDER: S-EPMC10999633 | biostudies-literature | 2024

REPOSITORIES: biostudies-literature

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The patterns of inbreeding depression in food-deceptive <i>Dactylorhiza</i> orchids.

Wróblewska Ada A Ostrowiecka Beata B Brzosko Emilia E Jermakowicz Edyta E Tałałaj Izabela I Mirski Paweł P

Frontiers in plant science 20240325

<h4>Introduction</h4>Inbreeding depression (ID) in food-deceptive plants have been reported previously, however, it has not been often proven that selfed seeds germinate better than outbred ones or that selfing affects ID. To resolved these issues, food-deceptive related <i>Dactylorhiza majalis</i>, <i>D. incarnata</i> var. <i>incarnata</i> and <i>D. fuchsii</i> orchids were investigated.<h4>Methods</h4>Hand pollination treatments and control pollination were conducted. Fruit set, number of seed ...[more]

PMID: 38590747

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