Miranda Marcela T, Pires Gabriel S, Pereira Luciano, de Lima Rodrigo F, da Silva Simone F, Mayer Juliana L S, Azevedo Fernando A, Machado Eduardo C, Jansen Steven, Ribeiro Rafael V
Laboratory of Plant Physiology 'Coaracy M. Franco', Center of Agricultural and Post-Harvest Biosystems, Agronomic Institute (IAC), Campinas, SP, Brazil.
Institute of Botany, Ulm University, Ulm, Germany.
Plant Cell Environ. 2024 Aug;47(8):3063-3075. doi: 10.1111/pce.14924. Epub 2024 Apr 25.
Embolism resistance of xylem tissue varies among species and is an important trait related to drought resistance, with anatomical attributes like pit membrane thickness playing an important role in avoiding embolism spread. Grafted Citrus trees are commonly grown in orchards, with the rootstock being able to affect the drought resistance of the whole plant. Here, we evaluated how rootstocks affect the vulnerability to embolism resistance of the scion using several rootstock/scion combinations. Scions of 'Tahiti' acid lime, 'Hamlin', 'Pera' and 'Valencia' oranges grafted on a 'Rangpur' lime rootstock exhibit similar vulnerability to embolism. In field-grown trees, measurements of leaf water potential did not suggest significant embolism formation during the dry season, while stomata of Citrus trees presented an isohydric response to declining water availability. When 'Valencia' orange scions were grafted on 'Rangpur' lime, 'IAC 1710' citrandarin, 'Sunki Tropical' mandarin or 'Swingle' citrumelo rootstocks, variation in intervessel pit membrane thickness of the scion was found. The 'Rangpur' lime rootstock, which is known for its drought resistance, induced thicker pit membranes in the scion, resulting in higher embolism resistance than the other rootstocks. Similarly, the rootstock 'IAC 1710' citrandarin generated increased embolism resistance of the scion, which is highly relevant for citriculture.
木质部组织的抗栓塞能力因物种而异，是与抗旱性相关的重要性状，诸如纹孔膜厚度等解剖学特征在避免栓塞扩散方面发挥着重要作用。嫁接的柑橘树通常种植在果园中，砧木能够影响整株植物的抗旱性。在此，我们使用几种砧木/接穗组合评估了砧木如何影响接穗的抗栓塞脆弱性。嫁接在“兰普”酸橙砧木上的“塔希提”酸橙、“哈姆林”、“佩拉”和“巴伦西亚”橙子的接穗表现出相似的抗栓塞脆弱性。在田间生长的树木中，叶片水势的测量结果表明在旱季没有明显的栓塞形成，而柑橘树的气孔对水分可用性下降呈现等水反应。当“巴伦西亚”橙子接穗嫁接在“兰普”酸橙、“IAC 1710”枸橼、“桑基热带”橘或“斯温格尔”枳柚砧木上时，发现接穗的导管间纹孔膜厚度存在差异。以抗旱性著称的“兰普”酸橙砧木诱导接穗形成更厚的纹孔膜，从而导致比其他砧木具有更高的抗栓塞能力。同样，“IAC 1710”枸橼砧木使接穗的抗栓塞能力增强，这对柑橘栽培具有高度相关性。
