Department of Agronomy, Food, Natural Resources, Animals and Environment - DAFNAE, University of Padua, Legnaro (PD), 35020, Italy.
Department of Agricultural, Forest and Food Sciences - DISAFA, University of Turin, Grugliasco, TO, 10095, Italy.
BMC Plant Biol. 2023 Sep 22;23(1):446. doi: 10.1186/s12870-023-04465-8.
Weeds represent a great constraint for agricultural production due to their remarkable adaptability and their ability to compete with crops. Climate change exacerbates the abiotic stresses that plants encounter. Therefore, studying plant responses to adverse conditions is extremely important. Here, the response to saline stress at different temperatures of three weed species (Chenopodium album, Echinochloa crus-galli and Portulaca oleracea) and three crops (maize, soybean and rice) was investigated.
The germination percentage of soybean notably decreased as salinity and low temperatures increased. In contrast, maize and rice consistently maintained a high germination percentage, particularly when subjected to low salinity levels. Regarding weed species, the germination percentage of C. album was not significantly affected by salinity, but it decreased in E. crus-galli and P. oleracea with increasing salinity. The mean germination time for all species increased with salinity, especially at lower temperatures. This effect was most pronounced for soybean and E. crus-galli. C. album exhibited significant reduction in stem growth with high salinity and high temperatures, while in E. crus-galli stem growth was less reduced under similar conditions.
This study showed that successful germination under saline stress did not ensure successful early development and emphasizes the species-specific nature of the temperature-salinity interaction, perhaps influenced by intraspecific variability. Increasing salinity levels negatively impacted germination and seedling growth in most species, yet higher temperatures partially alleviated these effects.
杂草因其极强的适应性和与作物竞争的能力，对农业生产构成了巨大的制约。气候变化加剧了植物所面临的非生物胁迫。因此，研究植物对不利条件的反应极为重要。在这里，研究了三种杂草（藜、稗草和马齿苋）和三种作物（玉米、大豆和水稻）在不同温度下对盐胁迫的反应。
随着盐度和低温的升高，大豆的发芽率显著下降。相比之下，玉米和水稻始终保持着较高的发芽率，特别是在低盐度下。就杂草种类而言，藜的发芽率不受盐度影响，但随着盐度的升高，稗草和马齿苋的发芽率下降。所有物种的平均发芽时间随盐度的升高而增加，特别是在较低的温度下。这种影响在大豆和稗草中最为明显。藜在高盐度和高温下的茎生长显著减少，而在类似条件下，稗草的茎生长减少较少。
本研究表明，在盐胁迫下成功发芽并不能保证早期发育的成功，并强调了温度-盐度相互作用的种特异性，这可能受到种内变异性的影响。盐度升高对大多数物种的发芽和幼苗生长都有负面影响，但较高的温度部分缓解了这些影响。
