Plant Stress Biology Laboratory, Institute of Environment and Sustainable Development, Banaras Hindu University, Varanasi, 221005, Uttar Pradesh, India.
Department of Earth Sciences, Indian Institute of Science Education and Research-Kolkata, Mohanpur, 741246, West Bengal, India.
Chemosphere. 2022 Apr;292:133482. doi: 10.1016/j.chemosphere.2021.133482. Epub 2021 Dec 31.
Thiourea (TU) is a chemo-priming agent and non-physiological reactive oxygen species (ROS) scavenger whose application has been found to reduce As accumulation in rice grains along with improved growth and yield. The present field study explored TU-mediated mechanistic changes in silicon (Si) assimilation in root/shoot, biochemical and molecular mechanisms of arsenic (As) stress amelioration in rice cultivars. Gosai and Satabdi (IET-4786) rice cultivars were selected for field experiment at three different places; control field and two other As contaminated experimental fields (EF1 and EF2) in West Bengal, India. The average As reduction was observed to be 9.5% and 19.8% whereas the yield increment was 8.8% and 17.7% for gosai and satabdi, respectively among all the three experimental fields. The positive interrelation was also observed between improved internal ultrastructure anatomy and enhanced Si assimilation (36%-423%) upon TU application. The level of photosynthetic pigments was increased by 29.8%-99.2%. Further, activities of antioxidant enzymes were harmonically altered in TU supplemented plants. The expression of various As related transporter genes in flag leaf and developing grains (inflorescence) was changed in both the rice cultivars (gosai and satabdi). It was also presumably responsible for observed As reduction in grains. Thus, TU application was found to be an efficient and sustainable agronomic practice for amelioration of As toxicity in rice plants in As contaminated field conditions.
硫脲 (TU) 是一种化学引发剂和非生理活性的活性氧 (ROS) 清除剂，其应用已被发现可减少稻米中砷的积累，同时提高生长和产量。本田间研究探讨了 TU 介导的根/茎中硅 (Si) 同化、水稻品种砷 (As) 胁迫缓解的生化和分子机制的变化。选择 Gosai 和 Satabdi（IET-4786）水稻品种在印度西孟加拉邦的三个不同地点进行田间试验；对照田和另外两个砷污染试验区 (EF1 和 EF2)。在所有三个试验区中，Gosai 和 Satabdi 的砷减少率分别为 9.5%和 19.8%，而产量增长率分别为 8.8%和 17.7%。在 TU 处理后，也观察到内部超微结构解剖和增强的 Si 同化之间存在正相关关系（36%-423%）。光合色素水平增加了 29.8%-99.2%。此外，抗氧化酶的活性在 TU 补充植物中得到了协调改变。两种水稻品种（Gosai 和 Satabdi）的旗叶和发育中的籽粒（花序）中的各种砷相关转运体基因的表达也发生了变化。这也可能是观察到籽粒中砷减少的原因。因此，TU 处理被发现是一种有效和可持续的农业实践，可以改善砷污染田间条件下水稻植株的砷毒性。
