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Desiccation Mitigates Heat Stress in the Resurrection Fern, Pleopeltis polypodioides.

ABSTRACT: Although heat and desiccation stresses often coincide, the response to heat especially in desiccation tolerant plants is rarely studied. We subjected hydrated Pleopeltis polypodioides fronds to temperatures up to 50°C and dehydrated fronds up to 65°C for 24 h. The effect of heat stress was evaluated using morphological changes, photosystem (PS) II efficiency, and metabolic indicators. Pinnae of dried fronds exposed to more than 40°C curled tighter and became brittle compared to fronds dried at lower temperatures. Exposure to > 50°C leads to discolored fronds after rehydration. Hydrated fronds turned partially brown at > 35°C. Chlorophyll fluorescence (F_t) and quantum yield (Q_y) increased following re-hydration but the recovery process after 40°C treatment lasted longer than at lower temperatures. Similarly, hydrated fronds showed reduced Q_y when exposed to > 40°C. Dried and hydrated fronds remained metabolically active up to 40°C. Hydroperoxides and lipid hydroperoxides in dried samples remained high up to 50°C, but decreased in hydrated fronds at > 40°C. Catalase (CAT) and glutathione (GSH) oxidizing activities remained high up to 40°C in dehydrated fronds and up to 35°C in hydrated fronds. Major fatty acids detected in both dehydrated and hydrated fronds included palmitic (C16:0) and stearic (C18:0) acids, oleic (18:1), linoleic (C18:2); and linolenic (C18:3) acids. Linolenic acid was most abundant. In dried fronds, all fatty acids decreased at > 35°C. The combined data indicate that the thermotolerance of dry fronds is about 55°C but is at least 10°C lower for hydrated fronds.

SUBMITTER: John SP

PROVIDER: S-EPMC7733933 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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Desiccation Mitigates Heat Stress in the Resurrection Fern, <i>Pleopeltis polypodioides</i>.

John Susan P SP Hasenstein Karl H KH

Frontiers in plant science 20201130

Although heat and desiccation stresses often coincide, the response to heat especially in desiccation tolerant plants is rarely studied. We subjected hydrated <i>Pleopeltis polypodioides</i> fronds to temperatures up to 50°C and dehydrated fronds up to 65°C for 24 h. The effect of heat stress was evaluated using morphological changes, photosystem (PS) II efficiency, and metabolic indicators. Pinnae of dried fronds exposed to more than 40°C curled tighter and became brittle compared to fronds dri ...[more]

PMID: 33329661

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Dataset Information

Desiccation Mitigates Heat Stress in the Resurrection Fern, Pleopeltis polypodioides.

Publications

Desiccation Mitigates Heat Stress in the Resurrection Fern, <i>Pleopeltis polypodioides</i>.

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