Abstract Detail

Ecology

Kuppler, Jonas [1].

Multivariate floral traits responses to water deficit.

The expression of floral traits can be strongly influenced by water availability. As under reduced water availability and physiological water stress, flowers are major drivers of water loss and energetically costly, plants are expected to produce smaller, fewer, and/or short-lived flowers or reduce water stress by aborting. This indicates that plants can respond and adapt to unfavorable conditions of insufficient water supply by reducing the overall floral area. Further, these directed responses also suggest that under water deficit specific trait expression or combination of trait expressions are especially favorable, i.e. there is a limited range of suitable phenotypes. This is in congruence with the stress-reduced variability hypothesis which states that intraspecific trait variation (= ITV) decreases with extreme abiotic conditions that generate stress. Extreme abiotic conditions have the potential to act as an environmental filter and/or strong selective agent, causing trait convergence within species and thus reducing ITV by decreasing phenotypic and genetic variation. Additionally, such environmental filters are likely to not only act on single traits but also act upon multiple traits simultaneously and thus, affecting also trait co-variance in addition to ITV. In contrast, the stress-induced variability hypothesis posits that abiotic stress increases ITV. In stressful conditions, phenotypic and genetic variation may increase owing to developmental instability and higher rates of recombination and mutation, in addition to competition avoidance when resources become less abundant. So far, nearly all studies exploring the effects of drought/water deficit on floral traits and flower-visitor interactions have focussed on shifts in mean trait values and compared multiple single traits. In this study, we explored the multivariate response of ITV, trait co-variance, and integration across studies using a meta-analytical approach and test the predictions that all ITV is decreasing and trait co-variance and integration is increasing with water deficit. Our results show how strong the environment limits the expression of multivariate floral phenotypes. With the predicted increases in drought and predicted shifts in pollinator species under climate change, a strong environmental impact on trait expression might impede with the adaption of floral traits to shifted pollinator communities.

1 - Ulm University, Institute of Evolutionary Ecology and Conservation Genomics, Albert-Einstein-Allee 11, Ulm, BW, 89081, Germany

Keywords:
Drought
floral traits
climate change.

Presentation Type: Oral Paper
Session: ECO5, Ecology: Stress
Location: /
Date: Thursday, July 22nd, 2021
Time: 12:45 PM(EDT)
Number: ECO5002
Abstract ID:347
Candidate for Awards:None