酸性土壤中的铝(Al)污染是稻田的主要问题,造成粮食产量损失,尤其是在泰国的中部平原。这项研究的目的是评估根组织中的铝含量,它易位到树叶,三种基因型水稻的铝毒性,RD35(局部耐酸),Azucena(阳性检查耐铝),和IR64(高产率)在0(对照)或1mMAlCl3(Al毒性)在pH4.5。水稻cv根组织中的Al含量。在1mMAlCl3下的RD35达到4.18mgg-1DW的峰值,并显着转移到叶片组织(0.35mgg-1DW),导致叶绿度(SPAD)降低(比对照降低44.9%)和净光合速率(Pn)下降(比对照降低54.5%)。相比之下,简历中的铝水平。Azucena和IR64在根中受到限制(2.12mgg-1DW),在叶组织中的易位量低(0.26mgg-1DW),导致保持SPAD和Pn的值。在简历中。RD35,根和芽性状,包括根长,根鲜重,射击高度,射击新鲜的重量,1mMAl处理中的芽干重比对照显着下降>35%,而这些参数在cvs中。保留了Azucena和IR64。根据结果,RD35水稻基因型被鉴定为铝敏感,因为它在地上和地下部分都显示出铝毒性,而Azucena和IR64被发现对1mMAl具有耐受性,因为它们证明了Al在根组织中的储存可以降低叶组织中的毒性。研究表明,根性状,射击属性,叶绿素降解,和光合还原可以成功地用于水稻育种计划中耐铝基因型的筛选。
Aluminum (Al) contamination in acidic soil is a major problem in paddy field, causing grain yield loss, especially in central plains of Thailand. The objective of this study was to assess Al content in the root tissues, its translocation to the leaves, and Al toxicity in three genotypes of rice, RD35 (local acidic-tolerant), Azucena (positive-check Al-tolerant), and IR64 (high yielding) under 0 (control) or 1 mM AlCl3 (Al toxicity) at pH 4.5. Al content in the root tissues of rice cv. RD35 under 1 mM AlCl3 was peaked at 4.18 mg g‒1 DW and significantly translocated to leaf tissues (0.35 mg g‒1 DW), leading to reduced leaf greenness (SPAD) (by 44.9% over the control) and declined net photosynthetic rate (Pn) (by 54.5% over the control). In contrast, Al level in cvs. Azucena and IR64 was restricted in the roots (2.12 mg g‒1 DW) with low amount of translocation in the leaf tissues (0.26 mg g‒1 DW), resulting in maintained values of SPAD and Pn. In cv. RD35, root and shoot traits including root length, root fresh weight, shoot height, shoot fresh weight, and shoot dry weight in 1 mM Al treatment were significantly dropped by > 35% over the control, whereas these parameters in cvs. Azucena and IR64 were retained. Based on the results, RD35 rice genotype was identified as Al sensitive as it demonstrated Al toxicity in both aboveground and belowground parts, whereas Azucena and IR64 were found tolerant to 1 mM Al as they demonstrated storage of Al in the root tissues to reduce toxicity in the leaf tissues. The study suggests that root traits, shoot attributes, chlorophyll degradation, and photosynthetic reduction can be successfully employed for the screening of Al-tolerant genotypes in rice breeding programs.