Frequent striped leaf albinism occurring in young seedlings leads to production loss of arecanut (Areca catechu L.) industry. Previous efforts has proved that this albinism phenotype was determined by genetic factors. However, the mechanism underlying albinism in arecanut remains unclear. In this study, to elucidate the regulatory mechanism of striped leaf albinism, comparison analysis was performed between leaves of normal and albinotic seedlings at physiological, biochemical and transcriptomic levels in arecanut. The albinotic leaves showed obvious degeneration in chloroplast, low chlorophyll content and reduced photosynthetic capacity. More than 5000 DEGs (differentially-expressed genes) was identified between normal and albinotic leaves. Among them, genes involved into the biosynthesis of chlorophyll, carotenoid and anthocyanin were significantly down-regulated in albinotic leaves. On the contrary, genes involved in leaf senescence and ABA (abscisic acid) synthesis were up-regulated in albinotic leaves. Unexpectedly, most genes involved in chloroplast development were up-regulated in albinotic leaves, indicating different regulatory mechanism of albinism in arecanut. Furthermore, transcription factor family genes, such as AP2/ERF-ERF (APETALA2/ethylene responsive factor), NAC (NAM/ATAF/CUC) and WRKY, were identified as DEGs between normal and albinotic leaves, which also indicated the senescence of albinotic leaves. The results indicated that the albinism mechanism of arecanut is different with those reported in other plants. Thus our data provides new insights into the mechanism underlying albinism. The genes related to albinism of arecanut identified in this study would be important targets for genetic modification or molecular markers development, which will be critical for improving the cultivation efficiency of this cash crop.

在年轻的幼苗中频繁发生的条纹叶白化病导致槟榔（槟榔（Areca catechu）L.）行业。先前的努力已经证明这种白化病的表型是由遗传因素决定的。但是，槟榔白化病的潜在机制仍不清楚。在这项研究中，为了阐明条纹叶白化病的调控机制，在槟榔中正常和白化病幼苗的叶片在生理，生化和转录组水平上进行了比较分析。白化病叶片叶绿体变性明显，叶绿素含量低，光合能力降低。在正常和白化病叶子之间鉴定出超过5000个DEG（差异表达基因）。其中，参与白化病叶片中叶绿素，类胡萝卜素和花色苷生物合成的基因被显着下调。反之，在白化病叶片中，参与叶片衰老和ABA（脱落酸）合成的基因被上调。出乎意料的是，大多数参与叶绿体发育的基因在白化病叶片中均上调，表明槟榔白化病的调控机制不同。此外，转录因子家族基因，例如AP2 / ERF-ERF（APETALA2 /乙烯反应因子），NAC（NAM / ATAF / CUC）和WRKY，被鉴定为正常叶片和白化病叶片之间的DEG，也表明白化病的衰老树叶。结果表明，槟榔白化机制与其他植物报道的机制不同。因此，我们的数据为白化病的潜在机制提供了新的见解。