Jaleel C Abdul, Manivannan P, Sankar B, Kishorekumar A, Gopi R, Somasundaram R, Panneerselvam R
Stress Physiology Lab, Department of Botany, Annamalai University, Annamalainagar 608002, Tamil Nadu, India.
Colloids Surf B Biointerfaces. 2007 Oct 15;60(1):110-6. doi: 10.1016/j.colsurfb.2007.06.006. Epub 2007 Jun 14.
The present investigation was conducted to determine whether CaCl(2) increases Catharanthus roseus drought tolerance and if such tolerance is correlated with changes in oxidative stress, osmoregulation and indole alkaloid accumulation. C. roseus plants were grown under water deficit environments with or without CaCl(2). Drought induced oxidative stress was measured in terms of lipid peroxidation (LPO) and H(2)O(2) contents, osmolyte concentration, proline (PRO) metabolizing enzymes and indole alkaloid accumulation. The plants under pot culture were subjected to 10, 15 and 20 days interval drought (DID) stress and drought stress with 5mM CaCl(2) and 5mM CaCl(2) alone from 30 days after planting (DAP) and regular irrigation was kept as control. The plants were uprooted on 41 DAS (10 DID), 46 DAS (15 DID) and 51 DAS (20 DID). Drought stressed plants showed increased LPO, H(2)O(2), glycine betaine (GB) and PRO contents and decreased proline oxidase (PROX) activity and increased gamma-glutamyl kinase (gamma-GK) activity when compared to control. Addition of CaCl(2) to drought stressed plants lowered the PRO concentration by increasing the level of PROX and decreasing the gamma-GK activities. Calcium ions increased the GB contents. CaCl(2) appears to confer greater osmoprotection by the additive role with drought in GB accumulation. The drought with CaCl(2)-treated C. roseus plants showed an increase in total indole alkaloid content in shoots and roots when compared to drought stressed and well-watered plants.
本研究旨在确定氯化钙是否能提高长春花的耐旱性，以及这种耐受性是否与氧化应激、渗透调节和吲哚生物碱积累的变化相关。长春花植株在有或没有氯化钙的水分亏缺环境中生长。通过脂质过氧化（LPO）和过氧化氢（H₂O₂）含量、渗透溶质浓度、脯氨酸（PRO）代谢酶和吲哚生物碱积累来测定干旱诱导的氧化应激。盆栽植物从种植后30天（DAP）开始，每隔10、15和20天进行一次干旱（DID）胁迫，以及单独施加5mM氯化钙和5mM氯化钙的干旱胁迫，以定期灌溉作为对照。在种植后41天（10次DID）、46天（15次DID）和51天（20次DID）将植株连根拔起。与对照相比，干旱胁迫植株的LPO、H₂O₂、甘氨酸甜菜碱（GB）和PRO含量增加，脯氨酸氧化酶（PROX）活性降低，γ-谷氨酰激酶（γ-GK）活性增加。向干旱胁迫植株添加氯化钙可通过提高PROX水平和降低γ-GK活性来降低PRO浓度。钙离子增加了GB含量。氯化钙似乎通过与干旱在GB积累中的累加作用提供了更大的渗透保护。与干旱胁迫和水分充足的植株相比，经氯化钙处理的干旱长春花植株地上部和根部的总吲哚生物碱含量增加。
