Department of Botany, MMV, Banaras Hindu University, Varanasi 221005, India.
Department of Botany, MMV, Banaras Hindu University, Varanasi 221005, India.
Plant Physiol Biochem. 2024 Nov;216:109186. doi: 10.1016/j.plaphy.2024.109186. Epub 2024 Oct 9.
Global population expansion has increased the demand for food supply and agricultural productivity. Abiotic stressors like temperature have significantly restricted agriculture in cropland and jeopardized food security. Cyanobacteria play a crucial role in fostering sustainable agriculture and ensuring global food security. In the present study, we have assessed the effect of temperatures on diazotrophic free living rice-field and hot-spring cyanobacteria. They were treated to a variable range of temperatures to see the changes in cellular morphology, physiology, and biochemical characteristics. The rise of temperatures induces growth (60 %), total protein (54 %) contents of rice-field cyanobacterium until 25 °C, further treatment results in decline (20 %) at 45 °C. However, growth indices were increased till 35 °C (90 %) in hot-spring cyanobacterium and further treatment did not exhibit a significant decline in the same. However, the reactive oxygen species (ROS) generation and lipid peroxidation (LPO) were higher in rice-field (2.8 and 1.7 fold) as compared to hot-spring cyanobacterium (2.2 and 1.6 fold). In response to temperature, enzymatic antioxidant contents were much higher in hot-spring as compared to rice-field cyanobacterium. Similarly, carotenoid and carbohydrate content was also higher in hot spring (2 fold) as compared to rice-field cyanobacterium (1.5 and 1.2 fold). All these data collectively suggest that hot-spring (Nostoc sp. strain VKB02) has a higher thermoprotective capacity with novel defense mechanisms as compared to rice-field cyanobacterium (Anabaena sp. strain VKB01). These findings contributed to a better understanding of the temperature stress, improvement of agricultural productivity and future welfare of green ecosystems.
全球人口的增长增加了对粮食供应和农业生产力的需求。非生物胁迫因素，如温度，极大地限制了农田的农业生产，并危及粮食安全。蓝细菌在促进可持续农业和确保全球粮食安全方面发挥着至关重要的作用。在本研究中，我们评估了温度对自由生活的稻田和温泉蓝细菌的固氮作用的影响。我们将它们暴露在不同温度范围下，观察细胞形态、生理和生化特征的变化。温度升高会诱导稻田蓝细菌的生长（60%）和总蛋白（54%）含量增加，直到 25°C；而在 45°C 时，进一步处理会导致下降（20%）。然而，在温泉蓝细菌中，生长指数在 35°C 时增加到 90%，进一步处理没有表现出显著下降。然而，温泉蓝细菌中活性氧（ROS）的产生和脂质过氧化（LPO）比稻田蓝细菌高（2.8 和 1.7 倍）。与稻田蓝细菌（2.2 和 1.6 倍）相比，温泉蓝细菌中的抗氧化酶含量在响应温度时更高。同样，温泉蓝细菌中的类胡萝卜素和碳水化合物含量也更高（2 倍），而稻田蓝细菌中则分别为 1.5 倍和 1.2 倍。所有这些数据表明，温泉蓝细菌（ Nostoc sp. 菌株 VKB02）与稻田蓝细菌（ Anabaena sp. 菌株 VKB01）相比，具有更高的热保护能力和新的防御机制。这些发现有助于更好地理解温度胁迫，提高农业生产力和绿色生态系统的未来福利。
