解析野生茄子物种的耐旱性：来自叶绿素荧光动力学的见解。

Deciphering desiccation tolerance in wild eggplant species: insights from chlorophyll fluorescence dynamics.

机构信息

ICAR-National Institute of Abiotic Stress Management, Baramati, Maharashtra, 413115, India.

ICAR-Central Arid Zone Research Institute, Jodhpur, Rajasthan, 342003, India.

出版信息

BMC Plant Biol. 2024 Jul 25;24(1):702. doi: 10.1186/s12870-024-05430-9.

DOI:10.1186/s12870-024-05430-9

PMID:39054439

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC11270916/

Abstract

BACKGROUND

Climate change exacerbates abiotic stresses, which are expected to intensify their impact on crop plants. Drought, the most prevalent abiotic stress, significantly affects agricultural production worldwide. Improving eggplant varieties to withstand abiotic stress is vital due to rising drought from climate change. Despite the diversity of wild eggplant species that thrive under harsh conditions, the understanding of their drought tolerance mechanisms remains limited. In the present study, we used chlorophyll fluorescence (ChlaF) imaging, which reveals a plant's photosynthetic health, to investigate desiccation tolerance in eggplant and its wild relatives. Conventional fluorescence measurements lack spatial heterogeneity, whereas ChlaF imaging offers comprehensive insights into plant responses to environmental stresses. Hence, employing noninvasive imaging techniques is essential for understanding this heterogeneity.

RESULTS

Desiccation significantly reduced the leaf tissue moisture content (TMC) across species. ChlaF and TMC displayed greater photosystem II (PSII) efficiency after 54 h of desiccation in S. macrocarpum, S. torvum, and S. indicum, with S. macrocarpum demonstrating superior efficiency due to sustained fluorescence. PSII functions declined gradually in S. macrocarpum and S. torvum, unlike those in other species, which exhibited abrupt declines after 54 h of desiccation. However, after 54 h, PSII efficiency remained above 50% of its initial quantum yield in S. macrocarpum at 35% leaf RWC (relative water content), while S. torvum and S. indicum displayed 50% decreases at 31% and 33% RWC, respectively. Conversely, the susceptible species S. gilo and S. sisymbriifolium exhibited a 50% reduction in PSII function at an early stage of 50% RWC, whereas in S. melongena, this reduction occurred at 40% RWC.

CONCLUSION

Overall, our study revealed notably greater leaf desiccation tolerance, especially in S. macrocarpum, S. torvum, and S. indicum, attributed to sustained PSII efficiency at low TMC levels, indicating that these species are promising sources of drought tolerance.

摘要

背景

气候变化加剧了非生物胁迫，预计这些胁迫将加剧对作物的影响。干旱是最普遍的非生物胁迫，它对全球农业生产有重大影响。由于气候变化导致的干旱加剧，提高茄子品种对非生物胁迫的抗性至关重要。尽管有许多野生茄子物种在恶劣条件下茁壮成长，但对其耐旱机制的了解仍然有限。在本研究中，我们使用叶绿素荧光（ChlaF）成像来研究茄子及其野生近缘种的耐旱性，该技术揭示了植物的光合作用健康状况。传统的荧光测量缺乏空间异质性，而 ChlaF 成像则可以全面了解植物对环境胁迫的反应。因此，采用非侵入性成像技术对于理解这种异质性至关重要。

结果

在所有物种中，干旱都会显著降低叶片组织水分含量（TMC）。在 S. macrocarpum、S. torvum 和 S. indicum 中，经过 54 小时的干旱处理后，ChlaF 和 TMC 显示出更高的 PSII 效率，其中 S. macrocarpum 由于持续的荧光而表现出更高的效率。PSII 功能在 S. macrocarpum 和 S. torvum 中逐渐下降，而其他物种则在经过 54 小时的干旱处理后突然下降。然而，在经过 54 小时后，PSII 效率在 S. macrocarpum 中仍保持在初始量子产量的 50%以上，此时叶片 RWC（相对水含量）为 35%，而 S. torvum 和 S. indicum 分别在 RWC 为 31%和 33%时表现出 50%的下降。相比之下，易感物种 S. gilo 和 S. sisymbriifolium 在 RWC 为 50%的早期阶段，PSII 功能就下降了 50%，而在 S. melongena 中，这种下降发生在 RWC 为 40%时。