Evidence map›Paper›PMID 41955574›Full record

ArticleAnnals of botany2026

Densely packed needles along the shoots of evergreen conifers exhibit shade-acclimated photosynthetic characteristics even under full sunlight.

Mitsutoshi Kitao, Kenichi Yazaki, Tetsuto Sugai, Hisanori Harayama, Evgenios Agathokleous, Ryouichi Tanaka

Abstract read
In one paragraph

Article in Annals of botany, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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0citing papers in PubMed
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1 · What the graph read from it

What it found

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2 · The registry

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

6 authors.

Mitsutoshi KitaoHokkaido Research Center, Forestry and Forest Products Research Institute, Sapporo 062-8516, Japan.ORCID 0000-0003-4806-0996
Kenichi YazakiHokkaido Research Center, Forestry and Forest Products Research Institute, Sapporo 062-8516, Japan.ORCID 0000-0002-7649-4081
Tetsuto SugaiHokkaido Research Center, Forestry and Forest Products Research Institute, Sapporo 062-8516, Japan.
Hisanori HarayamaDepartment of Plant Ecology, Forestry and Forest Products Research Institute, Tsukuba 305-8687, Japan.
Evgenios AgathokleousDepartment of Ecology, School of Ecology and Applied Meteorology, Nanjing University of Information Science & Technology (NUIST), Nanjing 210044, China.
Ryouichi TanakaInstitute of Low Temperature Science, Hokkaido University, Sapporo 060-0819, Japan.ORCID 0000-0002-5858-5326

Funding

JSPS KAKENHI JP23K26955JSPS KAKENHI JP24K01806
6 · The paper itself

Abstract

BACKGROUND AND

aimsEvergreen conifer shoots that develop under full sunlight eventually move to the shade within the canopy as the tree grows. We hypothesized that densely packed needles develop shade characteristics even under full sunlight due to mutual shading, allowing them to survive longer in the canopy shade.

methodsTo test this hypothesis, we measured photosynthetic light responses at the shoot and needle levels in four species: Picea glehnii (shade-intolerant), P. jezoensis (intermediate shade-tolerant), Abies sachalinensis (shade-tolerant) and Taxus cuspidata (highly shade-tolerant), grown under open (100 % sunlight) and shade (10 % sunlight) conditions. KEY

resultsIn P. glehnii, P. jezoensis and A. sachalinensis, needle-level photosynthetic and morphological traits showed minimal differences between light conditions, indicating the development of shade-characteristic needles even under full sunlight. In contrast, open-grown needles of T. cuspidata exhibited sun-acclimated traits, including higher photosynthetic capacity and thicker mesophyll tissue than shade-grown counterparts. Shoot-level photosynthetic capacity was higher in more shade-intolerant species with denser needle packing, and in open-grown seedlings across species.

conclusionsShoot-level acclimation to light environments in P. glehnii, P. jezoensis and A. sachalinensis was governed primarily by needle configuration. In T. cuspidata, it was influenced by both needle-level photosynthesis and shoot morphology. The presence of shade-characteristic needles along with reduced needle packing from age-related stem thickening may contribute to the longevity of evergreen conifer shoots under canopy shading.

Indexed as

AbiesAcclimatizationPhotosynthesisPiceaPlant LeavesPlant ShootsSunlightTaxusTracheophytaMutual shadingneedle configurationneedle longevityphotosynthetic light responseshade tolerance

Identifiers

PMID41955574
PMCPMC13319511

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.