Leifsonia xyli subsp. xyli (Lxx) is a pathogenic bacterium that causes Ratoon Stunting Disease (RSD) in the sugarcane crop. Disease symptoms caused by Lxx have been associated with hormonal imbalance, which may be intensified when plants are under water deficit conditions. However, up to date there are no studies showing that Lxx colonization decreases water status in sugarcane. The objective of this study was to evaluate the effect of water status and physiological traits of sugarcane colonized by Lxx under irrigation and water deficit conditions. We inoculated cuttings of the sugarcane genotype CB 49260 with Lxx using four treatments: i) healthy plants fully irrigated, ii) healthy plants under water deficit, iii) plants inoculated with Lxx fully irrigated, and iv) plants inoculated with Lxx under water deficit. Lxx inoculation in sugarcane did not affect relative water content (RWC) in the leaves, independently of the water conditions tested. For gas exchange and fluorescence traits, we did not identify differences between plants inoculated with Lxx and healthy plants. As expected, plants under water deficit conditions decreased RWC, CO₂ assimilation, stomatal conductance, transpiration and fluorescence traits, and increased soluble amino acids and proline contents in the leaves. Lxx inoculation increased amino acids and proline contents in plants under water deficit conditions. Therefore, the results indicated that sugarcane colonized with Lxx did not change plant water status independently of the water conditions during the entire growing season.

Xyli子叶亚种（Leifsonia xyli subsp。）xyli（Lxx）是一种致病细菌，可导致甘蔗作物的再生迟钝性病（RSD）。Lxx引起的病害症状与荷尔蒙失调有关，当植物处于缺水条件下时，荷尔蒙失调可能加剧。但是，迄今为止，尚无研究表明Lxx的定殖会降低甘蔗中的水分状况。这项研究的目的是评估在灌溉和缺水条件下，Lxx定植的甘蔗的水分状况和生理特性的影响。我们接种的甘蔗基因型CB 49260的岩屑LXX使用四个处理：我）充分灌溉的健康植物，ii）缺水的健康植物，iii）充分灌溉的Lxx接种的植物，和iv）缺水的Lxx接种的植物。甘蔗中Lxx的接种不会影响叶片中的相对含水量（RWC），而与所测试的水分条件无关。对于气体交换和荧光性状，我们未发现接种Lxx的植物与健康植物之间的差异。正如预期的那样，在缺水条件下的植物减少了RWC，CO ₂同化，气孔导度，蒸腾和荧光特性，以及叶片中可溶性氨基酸和脯氨酸含量的增加。在缺水条件下，Lxx接种增加了植物中的氨基酸和脯氨酸含量。因此，结果表明，在整个生长季中，Lxx菌落的甘蔗不会改变植物的水分状况，而与水的状况无关。