Kanna Venkatesan Kishanth, Djanaguiraman Maduraimuthu, Senthil Alagarswamy, Moorthy Ponnuraj Sathya, Iyanar Krishnamoorthy, Veerappan Anbazhagan
Department of Crop Physiology, Tamil Nadu Agricultural University, Coimbatore, India.
Department of Basic Engineering & Applied Sciences, Agricultural Engineering College & Research Institute, Kumulur, India.
Front Plant Sci. 2024 Dec 3;15:1478654. doi: 10.3389/fpls.2024.1478654. eCollection 2024.
Maize ( L.) is an important cereal crop grown in arid and semiarid regions of the world. During the reproductive phase, it is more frequently exposed to drought stress, resulting in lower grain yield due to oxidative damage. Selenium and zinc oxide nanoparticles possess inherent antioxidant properties that can alleviate drought-induced oxidative stress by the catalytic scavenging of reactive oxygen species, thereby protecting maize photosynthesis and grain yield. However, the effect of zinc selenide quantum dots (ZnSe QDs) under drought stress was not been quantified. Hence, the aim of this study was to quantify the (i) toxicity potential of ZnSe QDs and (ii) drought mitigation potential of ZnSe QDs by assessing the transpiration rate, photosynthetic rate, oxidant production, antioxidant enzyme activity and seed yield of maize under limited soil moisture levels. Toxicity experiments were carried out with 0 mg L to 500 mg L of ZnSe QDs on earthworms and azolla. The results showed that up to 20 mg L, the growth rates of earthworms and azolla were not affected. The dry-down experiment was conducted with three treatments: foliar spray of (i) water, (ii) ZnSe QDs (20 mg L), and (iii) combined zinc sulfate (10 mg L) and sodium selenate (10 mg L). ZnSe or Se applications under drying soil reduced the transpiration rate compared to water spray by partially closing the stomata. ZnSe application at 20 mg L at the tasselling stage significantly increased the photosynthetic rate (25%) by increasing catalase (98%) and peroxidase (85%) enzyme activity and decreased the hydrogen peroxide (23%) content compared to water spray, indicating that premature leaf senescence was delayed under rainfed conditions. ZnSe spray increased seed yield (26%) over water spray by increasing the number of seeds cob (42%). The study concluded that foliar application of ZnSe (20 mg L) could decrease drought-induced effects in maize.
玉米（L.）是一种在世界干旱和半干旱地区种植的重要谷类作物。在生殖阶段，它更频繁地遭受干旱胁迫，由于氧化损伤导致谷物产量降低。硒和氧化锌纳米颗粒具有固有的抗氧化特性，可通过催化清除活性氧来减轻干旱诱导的氧化应激，从而保护玉米的光合作用和谷物产量。然而，干旱胁迫下硒化锌量子点（ZnSe QDs）的作用尚未得到量化。因此，本研究的目的是通过评估有限土壤水分水平下玉米的蒸腾速率、光合速率、氧化剂产生、抗氧化酶活性和种子产量，来量化（i）ZnSe QDs的潜在毒性和（ii）ZnSe QDs的干旱缓解潜力。用0 mg/L至500 mg/L的ZnSe QDs对蚯蚓和满江红进行毒性实验。结果表明，浓度高达20 mg/L时，蚯蚓和满江红的生长速率未受影响。进行了干燥实验，设置三个处理：叶面喷施（i）水、（ii）ZnSe QDs（20 mg/L）以及（iii）硫酸锌（10 mg/L）和硒酸钠（10 mg/L）的混合物。与喷水相比，在土壤干燥条件下施用ZnSe或硒可通过部分关闭气孔来降低蒸腾速率。在抽雄期施用20 mg/L的ZnSe，与喷水相比，通过提高过氧化氢酶（98%）和过氧化物酶（8%）的活性显著提高了光合速率（25%），并降低了过氧化氢含量（23），这表明在雨养条件下延迟了叶片早衰。喷施ZnSe比喷水使种子产量提高了26%，这是通过增加每穗种子数（42%）实现的。该研究得出结论，叶面喷施ZnSe（20 mg/L）可减轻玉米干旱诱导的影响。
