Bioenergy grass [Erianthus ravennae (L.) Beauv.] secretes two members of mugineic acid family phytosiderophores which involved in their tolerance to Fe deficiency
Bioenergy grass [Erianthus ravennae (L.) Beauv.] secretes two members of mugineic acid family phytosiderophores which involved in their tolerance to Fe deficiency
复制标题
DOI：
10.1080/00380768.2017.1394168
复制
发表时间：
2017-01-01
影响因子：
2
通讯作者：
Nishizawa, Naoko K.
中科院分区：
文献类型：
--
作者：
Nozoye, Tomoko;Aung, May Sann;Nishizawa, Naoko K.
拉文纳草(Eriantus ravennae(L.)美人。(E.ravennae)是一种潜在的低投入、高生物质能作物。石灰性土壤缺铁是一个普遍存在的降低作物产量的农艺问题。铁在土壤pH值较高的好氧条件下很少溶解，例如在石灰性土壤中；因此，植物不能吸收足够的铁。提高石灰性土壤上的巨型牧草(如拉文纳草)的作物生产力，通过缓解环境问题具有积极的作用。然而，关于拉文纳草在石灰性土壤上的生长特性和铁的动态平衡特性，目前还知之甚少。在本研究中，我们对拉文纳草的特性进行了分析。与正常土壤相比，石灰性土壤中雷公藤的生长受到了损害。在石灰性土壤上，不同水肥条件下，雷公藤的生长情况不同；水淹条件下，添加微量营养素的情况下，雷公藤生长较好。这些结果表明，石灰性土壤中雷公藤生长受阻可能是微量营养素缺乏所致。我们发现，雷公藤根具有铁还原酶活性，在缺铁条件下，这种活性被上调。雷氏艾美耳球藻产生和分泌麦角酸(MA)和脱氧麦角酸(DMA)，从土壤中获取铁。MA的含量高于DMA。因此，雷公藤可能同时具有部分策略-I和策略-II铁吸收系统。通过大麦MA合成酶基因导入产生和分泌MA的转基因水稻间作雷公藤的生长表现出比单作水稻更好的生长，这表明增加MA的量增强了它们对缺铁的耐受性。我们的结果表明，在石灰性土壤上，通过增加MA的产生来增强雷公藤的铁吸收系统，有相当大的潜力来改善雷公藤的生长。
Ravenna grass, Erianthus ravennae (L.) Beauv. (E. ravennae) is a potential high biomass-energy crop with low input requirements. Iron (Fe) deficiency in calcareous soils is a widespread agronomic problem which reduces crop yields. Fe is sparingly soluble under aerobic conditions at high soil pH, such as in calcareous soils; therefore, plants cannot take up enough Fe. Increasing crop productivity of giant grasses, such as Ravenna grass in calcareous soil, has a positive effect by alleviating environmental problems. However, the growth character in calcareous soil and Fe homeostatic trait of Ravenna grass are largely unknown. In this study, we analyzed characteristics of Ravenna grass. The growth of E. ravennae plants were impaired in calcareous soil compared to those in the normal soil. In calcareous soil, the growth of E. ravennae plants differ among the water and fertilizer conditions; E. ravennae plants were grown better in the submerged condition adding micronutrient among conditions. These results suggested that impaired growth of E. ravennae in calcareous soil might be micronutrient shortage. We found that E. ravennae roots possess Fe reductase activities which were upregulated under Fe-deficient conditions. E. ravennae produced and secreted mugineic acid (MA) and deoxymugineic acid (DMA) to acquire Fe from the soil. The amount of MA was higher than that of DMA. Thus, E. ravennae might have both partial Strategy-I and Strategy-II Fe uptake systems. E. ravennae intercropped with transgenic rice plants producing and secreting MA through the introduction of the barley MA synthase gene showed improved growth compared to monocropped E. ravennae plants, suggesting that the increased amounts of MA enhanced their tolerance to Fe deficiency. Our results suggest that there is a considerable potential to improve the growth of E. ravennae plants in calcareous soils by enhancement of their Fe uptake systems through increase of MA production.