da Cruz, T.I.; Rocha, D.C.; Lanna, A.C.; Dedicova, B.; Vianello, R.P.; Brondani, C. Calcium-Dependent Protein Kinase 5 (OsCPK5) Overexpression in Upland Rice (Oryza sativa L.) under Water Deficit. Plants2023, 12, 3826.
da Cruz, T.I.; Rocha, D.C.; Lanna, A.C.; Dedicova, B.; Vianello, R.P.; Brondani, C. Calcium-Dependent Protein Kinase 5 (OsCPK5) Overexpression in Upland Rice (Oryza sativa L.) under Water Deficit. Plants 2023, 12, 3826.
da Cruz, T.I.; Rocha, D.C.; Lanna, A.C.; Dedicova, B.; Vianello, R.P.; Brondani, C. Calcium-Dependent Protein Kinase 5 (OsCPK5) Overexpression in Upland Rice (Oryza sativa L.) under Water Deficit. Plants2023, 12, 3826.
da Cruz, T.I.; Rocha, D.C.; Lanna, A.C.; Dedicova, B.; Vianello, R.P.; Brondani, C. Calcium-Dependent Protein Kinase 5 (OsCPK5) Overexpression in Upland Rice (Oryza sativa L.) under Water Deficit. Plants 2023, 12, 3826.
Abstract
Water deficit greatly affects global crop growth and productivity, particularly in water-limited environments like upland rice cultivation, leading to reduced grain yield. Plants activate various defense mechanisms during water deficit, involving numerous genes and complex metabolic pathways. Exploring orthologous genes, linked to enhanced drought tolerance, can aid functional validation in target species using genomic data from model organisms. Here, we studied the OsCPK5 gene in upland rice, an AtCPK6 ortholog from A. thaliana, by overexpressing it in the BRSMG Curinga cultivar. Transformants were assessed under two conditions: water deficit applied 79 days after seeding, lasting 14 days, followed by 7 days of irrigation at 80% field capacity. Physiological data and samples were collected at R3, R6, and R8 stages. GM plants consistently exhibited higher OsCPK5 gene expression across stages, peaking during grain filling. During this phase, GM plants displayed reduced stomatal conductance, photosynthetic rate, and increased water use efficiency compared to non-GM plants under drought. GM plants also exhibited higher filled grain percentage in both irrigation conditions. Their drought susceptibility index was 0.9 times lower than NGM plants, and they maintained a higher chlorophyll a/b index, indicating sustained photosynthesis. NGM plants under water deficit exhibited more leaf senescence, while OsCPK5-overexpressing plants retained green leaves. Overall, OsCPK5 overexpression induced diverse drought tolerance mechanisms, hinting at potential for future development of more drought-tolerant rice cultivars.
Keywords
Water use efficiency; Gene expression; Senescence; Drought
Subject
Biology and Life Sciences, Biology and Biotechnology
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
