Puppala Hemanth Kumar, Germer Jörn, Asch Folkard
Hans-Ruthenberg-Institute for Tropical Agricultural Sciences Universität Hohenheim Stuttgart Germany.
Plant Environ Interact. 2025 Jun 6;6(3):e70064. doi: 10.1002/pei3.70064. eCollection 2025 Jun.
To reduce pressure on arable land and water resources, crops can be grown in controlled environments that allow one to recuperate water transpired by plants. This would reduce water demand and potentially allow the use of saline water. However, condensing atmospheric water affects the vapor pressure deficit (VPD), which will affect plant transpiration, nutrient transport, salt uptake, and ultimate growth. This study examined responses of two genotypes of tomato and cucumber during the vegetative phase to varying VPD levels (3.1 and 1.9 kPa) and NaCl concentrations (0 and 30 mM) grown in hydroponic solutions. Under higher VPD (3.1 kPa), transpiration significantly increased in both tomato and cucumber, driving higher water loss. In tomatoes, higher VPD (3.1 kPa) increased the total dry biomass of the Saluoso genotype from 4.3 to 7.1 g and of the Sweeterno genotype from 4.9 to 7.3 g. Root zone salinity diminished the differences in biomass induced by VPD, with little effect on biomass accumulation in both tomato genotypes. Root zone salinity consistently reduced dry weight in cucumber, lowering Addison's from 15.5 to 9.5 g and Proloog's from 13.5 to 10.0 g, regardless of VPD. Unlike tomato, cucumber did not respond to VPD and was more sensitive to salinity. These findings indicate that in hydroponic cultivation, particularly in protected environments, the possibility of producing clean water alongside crop production depends on species-specific responses. In tomatoes, high VPD enhanced growth and demonstrated compatibility with the use of saline water, supporting the dual goal of productivity and water recovery. However, in cucumbers, the sensitivity to salinity and lack of response to VPD highlight the need for careful species selection and management to achieve sustainable water use and crop production.
为减轻对耕地和水资源的压力，可以在可控环境中种植作物，从而回收植物蒸腾的水分。这将减少用水需求，并有可能使用咸水。然而，冷凝大气中的水会影响蒸汽压亏缺（VPD），进而影响植物蒸腾、养分运输、盐分吸收及最终生长。本研究考察了两种基因型的番茄和黄瓜在营养生长阶段对水培溶液中不同VPD水平（3.1和1.9千帕）和NaCl浓度（0和30毫摩尔）的响应。在较高的VPD（3.1千帕）条件下，番茄和黄瓜的蒸腾作用均显著增强，导致水分流失增加。在番茄中，较高的VPD（3.1千帕）使萨卢索基因型的总干生物量从4.3克增加到7.1克，使斯威特诺基因型的总干生物量从4.9克增加到7.3克。根区盐分减少了VPD引起的生物量差异，对两种番茄基因型的生物量积累影响不大。无论VPD如何，根区盐分持续降低黄瓜的干重，使艾迪生品种从15.5克降至9.5克，使普罗洛格品种从13.5克降至10.0克。与番茄不同，黄瓜对VPD无响应，对盐分更敏感。这些发现表明，在水培种植中，特别是在保护设施环境中，与作物生产同时生产清洁水的可能性取决于物种特异性反应。在番茄中，高VPD促进生长，并证明与使用咸水具有兼容性，支持了生产力和水回收的双重目标。然而，在黄瓜中，对盐分的敏感性和对VPD的无响应突出了为实现可持续用水和作物生产而进行谨慎的物种选择和管理的必要性。
