Evaluation of PSII Thermal Stability in Grapevine Germplasm and Identification of Candidate Genes Based on a Genome-Wide Association Study
- 1National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, Zhengzhou Fruit Research Institute, Chinese Academy of Agricultural Sciences, Zhengzhou 450009, China
- 2Chuxiong Yunguo Agriculture Technology Research Institute, Chuxiong 675000, China
- 3Guangxi Academy of Agricultural Sciences, Nanning 530007, China
Abstract
Heat stress damages the photosynthetic apparatus of grapevine leaves. It also restricts plant growth and reduces fruit yield and quality. However, natural variation in photosystem II (PSII) thermal stability under heat stress in grapevine and its genetic basis remain poorly understood. Here, we evaluated 404 genetically diverse grapevine accessions. We measured the maximum quantum efficiency of photosystem II (Fv/Fm) after treatment at 47 °C. Phenotypic analysis, cluster analysis and genome-wide association analysis were then used to investigate the genetic basis of PSII thermal stability. The coefficient of variation for Fv/Fm increased from 4.52% at 25 °C to 40.60% at 47 °C. Wild accessions generally retained higher Fv/Fm than interspecific hybrids and Vitis vinifera cultivars. We also identified 21 accessions with relatively high PSII thermal stability. A genome-wide association analysis of 5,074,860 high-quality SNPs detected a suggestive association signal on chromosome 4. The lead SNP was Chr4_1743280_G_A. We integrated gene annotations within the associated interval, putatively functional variants and diplotype–phenotype comparisons. This analysis prioritized seven candidate genes potentially associated with variation in PSII thermal stability. The Hap2/Hap2 diplotype of Vitvi005414 was associated with higher Fv/Fm. However, these associations should be regarded as candidate hypotheses for further validation rather than evidence of causal relationships. These findings provide candidate loci, genes and diplotypes for understanding the genetic basis of PSII thermal stability. They also support the use of germplasm with relatively high PSII thermal stability, validation of candidate variants and future breeding for improved heat resilience.
Related
- Identification of germplasm and genomic markers associated with reduced T‐2 and HT‐2 mycotoxin accumulation in oat
- Genome-wide association study identifies candidate genes for body size and establishes a core germplasm set in Duoma sheep
- Phenotypic Diversity Analysis and Comprehensive Evaluation of Foxtail Millet Germplasm Resources Evaluated in Northern Xinjiang
- Comprehensive Evaluation of the Salt Tolerance of Soybean Germplasm Resources Cultivated by Heze Academy of Agricultural Sciences
- Association between soil properties and Grapevine Leaf Stripe Disease (Esca Complex) symptom expression. Part I: soil physical, hydrological and chemical characteristics
BibTeX
@article{wu2026evaluation,
title = {{Evaluation of PSII Thermal Stability in Grapevine Germplasm and Identification of Candidate Genes Based on a Genome-Wide Association Study}},
author = {Wentong Wu and Lei Sun and Rui Xu and Rongrong Guo and Jingyang Wang and Chenyang Hu and Xiucai Fan},
journal = {International Journal of Molecular Sciences},
year = {2026},
month = oct,
doi = {10.3390/ijms27209214},
url = {https://www.mdpi.com/1422-0067/27/20/9214},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Evaluation of PSII Thermal Stability in Grapevine Germplasm and Identification of Candidate Genes Based on a Genome-Wide Association Study
AU - Wentong Wu
AU - Lei Sun
AU - Rui Xu
AU - Rongrong Guo
AU - Jingyang Wang
AU - Chenyang Hu
AU - Xiucai Fan
PY - 2026
DA - 2026/10/01
JO - International Journal of Molecular Sciences
DO - 10.3390/ijms27209214
UR - https://www.mdpi.com/1422-0067/27/20/9214
AB - Heat stress damages the photosynthetic apparatus of grapevine leaves. It also restricts plant growth and reduces fruit yield and quality. However, natural variation in photosystem II (PSII) thermal stability under heat stress in grapevine and its genetic basis remain poorly understood. Here, we evaluated 404 genetically diverse grapevine accessions. We measured the maximum quantum efficiency of photosystem II (Fv/Fm) after treatment at 47 °C. Phenotypic analysis, cluster analysis and genome-wide association analysis were then used to investigate the genetic basis of PSII thermal stability. The coefficient of variation for Fv/Fm increased from 4.52% at 25 °C to 40.60% at 47 °C. Wild accessions generally retained higher Fv/Fm than interspecific hybrids and Vitis vinifera cultivars. We also identified 21 accessions with relatively high PSII thermal stability. A genome-wide association analysis of 5,074,860 high-quality SNPs detected a suggestive association signal on chromosome 4. The lead SNP was Chr4_1743280_G_A. We integrated gene annotations within the associated interval, putatively functional variants and diplotype–phenotype comparisons. This analysis prioritized seven candidate genes potentially associated with variation in PSII thermal stability. The Hap2/Hap2 diplotype of Vitvi005414 was associated with higher Fv/Fm. However, these associations should be regarded as candidate hypotheses for further validation rather than evidence of causal relationships. These findings provide candidate loci, genes and diplotypes for understanding the genetic basis of PSII thermal stability. They also support the use of germplasm with relatively high PSII thermal stability, validation of candidate variants and future breeding for improved heat resilience.
SN - 1422-0067
ER -