Low O2 supply is involved in the poor growth in root-restricted plants of tomato (Lycopersicon esculentum Mill.)
Low O2 supply is involved in the poor growth in root-restricted plants of tomato (Lycopersicon esculentum Mill.)
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DOI：
10.1016/j.envexpbot.2007.05.010
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发表时间：
2007-11
影响因子：
5.7
通讯作者：
K. Shi;W. Hu;D. Dong;Yanhong Zhou;Jingquan Yu
中科院分区：
文献类型：
--
作者：
K. Shi;W. Hu;D. Dong;Yanhong Zhou;Jingquan Yu
以番茄（Lycopersicon esculentum Mill.）植物水培生长并在有或没有补充通气的情况下进行根限制。在整个实验过程中，研究了植物生物量、叶片营养浓度、营养液中溶解氧浓度、根呼吸、根水解ATP酶活性、木质部汁液脱落酸（阿坝）浓度、水分关系、叶片气体交换和根细胞活力。根限制显着抑制根和芽的生长，早在15天后处理，这种抑制作用缓解了限制根区周围的积极通风。生长抑制根限制发生伴随着急剧下降的溶解O2浓度在溶液中，连同显着降低根总呼吸，细胞色素途径的能力，水解ATP酶活性，和根细胞活力。然而，没有这样的减少被发现在通气根限制植物。根系限制诱导的生长抑制与叶片中的营养水平无关，并且与叶水势的下降或气体交换无关。根限制导致木质部汁液阿坝浓度增加，从第15天到实验结束，但没有观察到这样的效果在良好的通气植物。因此，O2可能是限制根系生长的主要限制因子之一。
To investigate whether O2deficit is involved in the depressed shoot growth under root restriction condition, tomato (Lycopersicon esculentum Mill.) plants were grown hydroponically and subjected to root restriction with or without supplemental aeration. Plant biomass, leaf nutrient concentration, dissolved O2concentration in nutrient solution, root respiration, root hydrolytic ATPase activities, xylem sap abscisic acid (ABA) concentration, water relations, leaf gas exchange, and root cell viability were investigated throughout the experiment. Root restriction significantly depressed root and shoot growth as early as 15 days after treatment and this depressive effect was alleviated by vigorous aeration around the restricted root zone. Growth suppression by root restriction occurred concomitantly with sharp decreases in dissolved O2concentration in solution together with significant decreases in root total respiration, cytochrome pathway capacity, hydrolytic ATPase activities, and root cell viability. However, no such decreases were found in well aerated root restriction plants. Root restriction-induced growth suppression was independent of nutrients level in leaves and was not primarily related to the decline of leaf water potential or the gas exchange. Root restriction resulted in an increase in xylem sap ABA concentration from day 15 to the end of the experiment but no such effect was observed in well aerated plants. It is likely therefore, that O2was one of the main limiting factors to the reduced shoot growth under root restriction condition.