Raheb Samaneh, Noorizadeh Sina, Golmohammadi Morteza, Khankahdani Hamed Hassanzadeh
Horticultural Science Research Institute, Citrus and Subtropical Fruits Research Center, Agricultural Research Education and Extension Organization (AREEO), Ramsar, Iran.
Agriculture Organization of Fars Province, Shiraz, Iran.
Sci Rep. 2025 Aug 26;15(1):31419. doi: 10.1038/s41598-025-16988-1.
Unfortunately, over the past two decades, Mexican lime orchards have faced a significant threat from witches' broom disease of lime (WBDL), associated with 'Candidatus Phytoplasma aurantifolia', leading to the ruin of many orchards in southern Iran. One effective strategy for controlling vector-borne diseases like WBDL is to find and use tolerance/resistance genotypes. Although a number of studies have shown that using tolerated cultivars, rootstocks or scion/rootstock combinations may affect phytoplasma disease severity, no studies have compared different Mexican lime genotypes/rootstock combinations against 'Ca. P. aurantifolia' infection. This study assessed the tolerance and response of four Mexican lime genotypes (G5, G8, G16 and G17) grafted on two commercial rootstocks (including Mexican lime and sour orange) against WBDL under controlled conditions. The results showed that foliar disease expression was observed in all limes grafted on Mexican lime. Disease symptoms were not recorded in lime genotypes × sour orange except G5. All lime genotypes grafted on the two commercial citrus rootstocks were infected with 'Ca. P. aurantifolia' at varying rates. However, in the three genotypes grafted on sour orange rootstock, the phytoplasma titer was significantly reduced. Furthermore, growth parameters, including leaf width and length, internode length, and greenness, showed fewer significant differences compared to control. The findings of this study enhance our understanding of the influence of rootstock on the performance of WBDL-infected citrus in controlled greenhouse conditions and acknowledge that WBDL management may require tolerance of both scions and rootstocks.
不幸的是，在过去二十年中，墨西哥酸橙果园面临着来自酸橙扫帚病（WBDL）的重大威胁，该病与“Ca. Phytoplasma aurantifolia”有关，导致伊朗南部许多果园被毁。控制像WBDL这样的媒介传播疾病的一种有效策略是寻找并使用耐受性/抗性基因型。尽管许多研究表明，使用耐受性品种、砧木或接穗/砧木组合可能会影响植原体病害的严重程度，但尚无研究比较不同的墨西哥酸橙基因型/砧木组合对“Ca. P. aurantifolia”感染的抗性。本研究在可控条件下评估了嫁接在两种商业砧木（包括墨西哥酸橙和酸橙）上的四种墨西哥酸橙基因型（G5、G8、G16和G17）对WBDL的耐受性和反应。结果表明，嫁接在墨西哥酸橙上的所有酸橙都观察到了叶部病害表现。除G5外，酸橙基因型×酸橙未记录到病害症状。嫁接在两种商业柑橘砧木上的所有酸橙基因型均以不同速率感染了“Ca. P. aurantifolia”。然而，在嫁接在酸橙砧木上的三种基因型中，植原体滴度显著降低。此外，与对照相比，包括叶宽和叶长、节间长度和绿度在内的生长参数显示出较少的显著差异。本研究的结果增进了我们对砧木在可控温室条件下对感染WBDL的柑橘表现的影响的理解，并认识到WBDL的管理可能需要接穗和砧木都具有耐受性。
