Moles Tommaso Michele, Pompeiano Antonio, Huarancca Reyes Thais, Scartazza Andrea, Guglielminetti Lorenzo
Department of Agriculture, Food and Environment, University of Pisa, Pisa, Italy.
Laboratory of Ecological Plant Physiology, Global Change Research Institute CAS, Brno, Czech Republic.
Plant Physiol Biochem. 2016 Dec;109:262-272. doi: 10.1016/j.plaphy.2016.10.008. Epub 2016 Oct 12.
Landraces represent an important part of the biodiversity well-adapted under limiting environmental conditions. We investigated the response of two Southern Italy tomato landraces, the well-known San Marzano (our commercial standard) and a local accession called "Ciettaicale", to different levels of sodium chloride in water irrigation (from 0 up to 600 mM) for a short-time exposure (one week). The combination of the chlorophyll a fluorescence and gas exchange analyses suggested that Ciettaicale maintained a higher efficiency of photosystem II (PSII) photochemistry and CO utilization at high salinity concentrations than San Marzano. Stomatal and non-stomatal limitations occurred in San Marzano according to the reduction of maximum efficiency of PSII photochemistry and the increase of intercellular CO concentration. Higher Na/K ratio and higher concentration of total soluble sugars contributed to non-stomatal limitations in San Marzano leaves. These effects were significantly less evident in Ciettaicale. We also observed changes in total antioxidant capacity and leaf pigment content that emphasized the occurrence of modifications in the photosynthetic apparatus according to salt gradient. The more efficient assimilates supply and an integrated root protection system provided by sugars and antioxidants can explain the significantly higher root/shoot ratio in Ciettaicale. Overall, our results suggest that a comprehensive assessment of salinity tolerance in a genotypes comparison could be also obtained evaluating plant response to high salinity levels at early vegetative stage. In addition, further studies will be carried out in order to evaluate the possibility of using Ciettaicale in tomato improvement programs.
地方品种是生物多样性的重要组成部分，能很好地适应有限的环境条件。我们研究了意大利南部的两个番茄地方品种，著名的圣马扎诺（我们的商业标准品种）和一个名为“Ciettaicale”的当地品种，在短期暴露（一周）于不同水平氯化钠（从0到600 mM）水灌溉条件下的反应。叶绿素a荧光和气体交换分析的结合表明，在高盐浓度下，“Ciettaicale”比圣马扎诺维持了更高的光系统II（PSII）光化学效率和CO2利用效率。随着PSII光化学最大效率的降低和细胞间CO2浓度的增加，圣马扎诺出现了气孔和非气孔限制。较高的Na/K比和较高的总可溶性糖浓度导致了圣马扎诺叶片的非气孔限制。这些影响在“Ciettaicale”中明显不那么明显。我们还观察到总抗氧化能力和叶片色素含量的变化，这些变化强调了光合机构根据盐梯度发生的改变。糖和抗氧化剂提供的更有效的同化物供应和综合的根系保护系统可以解释“Ciettaicale”中显著更高的根/茎比。总体而言，我们的结果表明，在基因型比较中对耐盐性进行全面评估，也可以通过评估植物在营养生长早期对高盐水平的反应来获得。此外，将开展进一步研究，以评估在番茄改良计划中使用“Ciettaicale”的可能性。
