WATER-RETAINING POLYMER MITIGATES THE WATER DEFICIT IN Schinus terebinthifolia: PHOTOSYNTHETIC METABOLISM AND INITIAL GROWTH

Abstract

The use of water-retaining polymer (hydrogel) can mitigate the damage to the photosynthetic apparatus and increase the robustness of young plants under water deficit conditions. Thus, the aim of this study was to evaluate the effect of water-retaining polymer on the morphophysiological aspects of Schinus terebinthifolia Raddi submitted to water deficit. The studied water regimes were characterized by three plant irrigation management: 1) control: irrigated daily, 2) stress: water deficit (irrigation suspension) and 3) stress + hydrogel: water deficit + water-retaining polymer. The plants were submitted to irrigation suspension until photosynthesis approached zero [1 st P0], followed by resumption of irrigation (REI) for 15 days. After REI, until recovery of photosynthetic rate of plants, the maintenance of irrigation of all plants for 90 days, characterizing the final recovery (125 th day of experiment). The photosynthetic rate reached values close to zero in plants under stress on the 20 th day of water restriction, whereas the plants in conditions with hydrogel did not show a decrease in leaf metabolism. Excluding intercellular CO2 concentration, physiological parameters were lower on 1 st P0 in plants under water deficit grown without hydrogel than those in plants grown with hydrogel, but all plants showed physiological plasticity. The use hydrogel contributed to the maintenance of the photosynthetic capacity of S. terebinthifolia under water deficit.

Does silicon help to alleviate water deficit stress and in the recovery of Dipteryx alata seedlings?

“…The same responses for LA were observed in seedlings of Schinus terebinthifolia Raddi (Beltramin et al, 2020), Cedrela odorata L. (Silva et al, 2021), and Campomanesia xanthocarpa O. Berg. (Santos et al, 2021), where these species had reduction in LA under low water availability.…”

Salicylic acid alleviates the water stress on photochemical apparatus and quality of Schinus terebinthifolia seedlings

“…In the context of the global climate change, water deficit stress is a major problem, as it adversely affects plant productivity and silvicultural activities. Under stress conditions, the intercellular CO 2 concentration in the substomatal chamber increases (Beltramin et al, 2020;Zandi & Schung, 2022), causing oxidative damage to chloroplasts and reducing photosynthetic pigment synthesis, thereby impairing the activities of photosystem II (PSII) and plant growth (Santos et al, 2021;Xia et al, 2022).…”

“…It is fast growing and bears small reddish fruits that are attractive to wildlife (Lorenzi, 2008), and thereby it is a useful species for programs to restore degraded areas and agroforestry systems. However, water restriction is a limiting factor for the growth and physiology of this species (Beltramin et al, 2020).…”

Ascophyllum nodosum seaweed extract in Inga edulis seedlings under drought and the potential of phenotypic plasticity

“…In recent years, drastic reductions in soil water status have been veri ed due to droughts, resulting from climate changes, which promote increase of atmospheric temperature and changes in precipitation distribution (Beltramin et al 2020;Santos et al 2022). Under conditions of water stress, several alterations in the morphophysiological responses and the survival of plants in different phytophysiognomies in the world may occur.…”