Heat stress and recovery effects on the physiology and biochemistry of Castanea sativa Mill.

Abstract

Chestnut forests are undergoing increasing heat stress due to the current global warming, but little is known about the physiology and biochemistry responses of Castanea sativa Mill. to heat or whether differences exist between populations. Six-month-old seedlings from three climatically contrasting populations of C. sativa (from the north, centre, and south of Spain) were subjected to control and heat stress conditions for 7 days. The effects of heat stress on seedlings and their recovery (10 days after heat stress) were described by assessment of visible symptoms, growth, mortality, and leaf gas exchange of plants, quantification of compounds involved in the primary and secondary metabolism, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging. In response to stress, plant biomass decreased, and plant biochemistry altered depending on the tissue and the population. Major alterations in the primary metabolism of stressed plants occurred in leaves, characterized by increased levels of soluble sugars, nitrogen, and proline, and depletion of starch. Increased levels of soluble sugars and starch depletion occurred mostly in seedlings from the southern population, while proline increase occurred only in the northern population. Secondary metabolism of seedlings experienced the highest variation below ground, and roots of heat-stressed plants increased the content of phenolic compounds. LC-MS analysis permitted identification and quantification of six compounds induced by heat, five of which were detected in the roots. Differential biochemistry responses to heat stress were observed among populations. At recovery, most of the altered parameters had returned to control conditions, suggesting high resilience to heat stress in this Mediterranean tree species. This is the first study to address the effects of heat stress on the physiology and biochemistry of C. sativa and their interpopulation variability. Most parameters were significantly influenced by the interaction of population and heat treatment, indicating that genetic differentiation controlled the phenotypic differences of C. sativa in response to heat stress. Extensive genetic variation in plasticity in physiological and biochemical parameters in response to heat stress reveals an opportunity for chestnut for global warming-mediated selection.

Warming Scenarios and Phytophthora cinnamomi Infection in Chestnut (Castanea sativa Mill.)

“…Similarly, in Quercus suber seedlings exposed to low temperatures, a higher concentration of flavonoids was reported compared to control plants, suggesting that the biosynthesis of these compounds was encouraged by low temperatures [ 60 ]. In similar aged C. sativa seedlings subjected to heat stress, an increase in phenolic compounds was observed in roots [ 28 ], although the response varied depending on the tree origin. In trees, the biosynthesis of secondary metabolites in response to heat appears to be species- and compound-dependent [ 12 ].…”

“…Delayed changes or shifts in trends in phenolic content occur when plants have entered a recovery phase after stress [ 57 , 59 , 61 , 62 ]. During the recovery phase, plants tend to restore phenolic content to ambient temperature levels, unless physiological damage occurs [ 28 , 63 ]. The increase in several phenolic compounds in our heat-wave-stressed plants may have occurred as a consequence of stress memory, as observed for Alopecurus pratensis [ 62 ], but this needs further study to be confirmed.…”

“…Because this species developed in contrasting climate conditions, different evolutionary pressures acted on its genome, giving rise to ecotypes adapted to different climates [ 18 , 22 , 23 , 24 ]. The genetic variability, physiology and biochemistry of chestnut in response to heat and drought stress have been studied [ 24 , 25 , 26 , 27 , 28 , 29 ], providing knowledge for breeders to obtain plant material resilient to the new conditions of climate change. However, little information is available on the response of C. sativa to combined abiotic and biotic stress.…”

Impact of Climate Change on the Chemical Compositions and Antioxidant Activity of Mentha pulegium L.

“…These changes in the Earth’s meteorological parameters are alarming consequences of climate change . These changes are the results of the intensification of greenhouse gas emissions . Furthermore, global warming has already reached 1.1 °C in recent years compared to the preindustrial era, and its impact on ecosystems is more severe than estimated in previous reports.…”

A comparative study of stress response in mung beans (Vigna radiata L.) under low intensity electromagnetic field and heat shock

“…In the other hand heating stress also affects plant growth, development (Dorado et al, 2023), oxidative status , water balance (Dinler et al, 2023), protein folding (Yadav et al, 2020) etc. heating causes physiological wilting in plants, which forces plants to respond with solute accumulations (Parrotta et al, 2020).…”