Leaf antioxidant activity in Colombian elite Hevea brasiliensis genotypes as a breeding strategy for water deficit tolerance under Amazonia conditions

• Published in: PloS one 2024-09, Vol.19 (9), p.e0306083
• Main Authors: Guaca-Cruz, Lised, Sterling, Armando, Clavijo, Andrés, Suárez-Salazar, Juan Carlos
• Format: Article
• Language: English
• Subjects: Aluminum; Analysis; Antioxidants; Antioxidants - metabolism; Biology and Life Sciences; Carotenoids; Carotenoids - metabolism; Colombia; Cultivars; Developmental stages; Droughts; Earth Sciences; Environmental conditions; Enzymes; Genotype; Genotype & phenotype; Genotypes; Growth; Growth stage; Hevea - genetics; Hevea - metabolism; Hevea brasiliensis; Humidity; Influence; Leaves; Lipid Peroxidation; Lipids; Malondialdehyde - metabolism; Metabolic response; Nitrogen; Peroxidation; Photons; Photosynthesis - genetics; Photosynthetic pigments; Photosynthetically active radiation; Physical Sciences; Plant breeding; Plant Breeding - methods; Plant Leaves - genetics; Plant Leaves - metabolism; Precipitation; Proline; Reactive oxygen species; Reactive Oxygen Species - metabolism; Rubber; Rubber trees; Sea level; Seasonal variations; Seasons; Sugar; Temperature; Trees; Water; Water - metabolism; Water availability; Water deficit; Water shortages
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0306083

This study evaluated the foliar antioxidant activity in nine Hevea brasiliensis genotypes from the ECC-1 (Élite Caquetá Colombia) selection and IAN 873 cultivar (control) in trees in the growth stage in two large-scale clonal trials in response to different climatic (semi-humid warm and humid warm sites) and seasonal (dry and rainy periods) conditions in the Colombian Amazon. The results indicated that Reactive Oxygen Species (ROS) production increased under conditions of lower water availability (dry period), leading to lipid peroxidation, high defense of photosynthetic pigments, and development of better osmotic adjustment capacity in the ECC 64, IAN 873, ECC 90, and ECC 35 genotypes due to high concentrations of carotenoids (0.40 mg g-1), reducing sugars (65.83 μg mg-1), and malondialdehyde (MDA) (2.44 nmol ml-1). In contrast, during the rainy period, a post-stress action was observed due to high contents of proline and total sugars (39.43 μg g-1 and 173.03 μg g-1, respectively). At the site level, with high Photosynthetically Active Radiation (PAR) values (1143 moles photons m-2 s-1), temperature (32.11°C), and lower precipitation (135 mm), higher antioxidant activity (chlorophylls a, b and total, carotenoids, and proline) was recorded at the humid warm site, demonstrating that the ECC 90, ECC 64, and ECC 66 genotypes are tolerant to water deficit compared to IAN 873. The ECC 64 genotype, independent of seasonal changes and site conditions, presented the highest contents in Chl a, total Chl, reducing sugars, total sugars, and MDA, showing a tendency to adapt to fluctuating conditions. This study showed that water fluctuations do not cause the same metabolic responses, these vary within the same species, depending on their developmental stage and the climatic and seasonal variations characteristic of the Colombian Amazon.