Contrasting effects of experiencing temporally heterogeneous light availability versus homogenous shading on plant subsequent responses to light conditions

Abstract

Temporally heterogeneous environments is hypothesized to correlate with greater plasticity of plants, which has rarely been supported by direct evidence. To address this issue, we subjected three species from different ranges of habitats to a first round of alternating full light and heavy shading (temporally heterogeneous light experience), constant moderate shading and full light conditions (temporally homogeneous light experiences, control) and a second round of light-gradient treatments. We measured plant performance in a series of morphological, biomass, physiological and biochemical traits at the end of each round. Compared to constant full light experience, temporally heterogeneous light conditions induced immediate active biochemical responses (in the first round) with improved late growth in biomass (during the second round); constant moderate shading experience increased photosynthetic physiological and biomass performances of plants in early response, and decreased their late growth in biomass. The karst endemic species of Kmeria septentrionalis showed greater improvement in late growth of biomass and lower decrease in biochemical performance, due to early heterogeneous experience, compared to the non-karst species of Lithocarpus glaber and the karst adaptable species of Celtis sinensis. Results suggested plants will prefer to produce morphological and physiological responses that are less reversible and more costly in the face of more reliable environmental cues at early stage in spite of decreased future growth potential, but to produce immediate biochemical responses for higher late growth potential when early environmental cues are less reliable, to avoid the loss of high costs and low profits. Typical karst species should be more able to benefit from early temporally heterogeneous experience, due to long-term adaptation to karst habitats of high environmental heterogeneity and low resource availability.

A high-quality chromosome-level genome assembly of the endangered tree Kmeria septentrionalis

“…Kmeria septentrionalis Dandy, commonly known as the unisexual magnolia or Magnolia kwangsiensis [NCBI Taxonomy ID: 86722], is a remarkable monoecious floral species within the ancient Magnoliaceae family 1 , 2 . As one of China’s most critically endangered plant species, K. septentrionalis holds pivotal significance in maintaining biodiversity 3 .…”

Transcriptomics of Leaf Development in the Endangered Dioecious Magnolia kwangsiensis: Molecular Basis Underpinning Specialized Metabolism Genes

“…The Magnolia kwangsiensis , colloquially known as the dioecious magnolia or by its other aliases, the finely stamened Magnolia and the Huan-Yong tree Woonyoungia septentrionalis , holds a singular place in the Magnoliaceae family as the sole plant recognized for its unisexual flowers and separate male and female trees [ 1 , 2 ]. This unique floral architecture has drawn considerable attention to the species from a botanical and a conservation perspective, necessitating in-depth exploration into its biology and ecological impact [ 1 , 3 ].…”

“…Endemic to China, the species marks its presence exclusively within the territories of Guangxi, Guizhou, and Yunnan [ 2 , 4 ]. Among these localities, the Huanjiang Mulun National Nature Reserve is distinguished for harboring one of the largest contiguous populations of dioecious Magnolias with a mere estimate of 200 mature individuals remaining—underscoring its rarity and the critical need for immediate protective measures [ 3 , 5 ]. According to the “Regulations on the Protection of Wild Plants”, which the People’s Republic of China issued, the dioecious magnolia is classified as a first-class national key protected wild plant.…”

“…The “China Red Data Book of Endangered Species”, compiled by the Biodiversity Working Group of the China Council for International Cooperation on Environment and Development, further categorizes it as an endangered species. Globally, its vulnerability is recognized and echoed by the International Union for Conservation of Nature (IUCN), which lists the M. kwangsiensis as a critically endangered species within its universally accepted grading system of threatened plants [ 1 , 2 , 3 , 4 ]. These classifications underscore the urgency to sincerely preserve and understand this extraordinary species to ensure its continuity and well-being within the ecosystem.…”

“…Globally, its vulnerability is recognized and echoed by the International Union for Conservation of Nature (IUCN), which lists the M. kwangsiensis as a critically endangered species within its universally accepted grading system of threatened plants [1][2][3][4]. These classifications underscore the urgency to sincerely preserve and understand this extraordinary species to ensure its continuity and well-being within the ecosystem.…”