Different Ways of Maintaining Water Balance in Leaves in Two Populations of C₄Atriplex tatarica Differing in Productivity and Drought Tolerance.

Rakhmankulova, Z. F.; Shuyskaya, E. V.; Voronin, P. Yu.

The effects of water deficiency (–0.3 MPa) on plant growth, the water and proline content, fluorescence parameters chlorophyll PSI and II, and CO2/H2O gas exchange in plant leaves were studied in two populations of xero-halophyte Atriplex tatarica L. (C4 NAD-ME) with contrasting productivity. Based on growth parameter analysis, a less-productive population (P1) was more tolerant of osmotic stress, and a more-productive population (P2) was less tolerant. The studied populations demonstrated different ways of maintaining the water balance in leaves. P1 was characterised by an insensitivity of its stomatal apparatus, a significant decrease in water potential of mesophyll cells' apoplast in substomatal cavity, an increase in proline content, and activation of PSI cyclic electron transport in leaves. In P2, maintaining the water content in leaves under stress conditions was achieved by stomatal closure. The impact of stress was manifested by decreased intensity of photosynthesis, transpiration, PSII efficiency and more intensified of dark respiration in P2. Thus, various ways by which to maintain the water balance in plant leaves in two populations were revealed under weak osmotic stress.

DROUGHT tolerance; DROUGHTS; PLANT-water relationships; ELECTRON transport; STOMATA; PLANT growth

Russian Journal of Plant Physiology, 2021, Vol 68, Issue 6, p1143

1021-4437

Academic Journal

10.1134/S1021443721060170