ABSTRACT

Citrus growth is often constrained by salinity, but citrus rootstocks respond to salinity differently. A greenhouse study was carried out in a completely randomized design with three cultivars of mandarin (‘Younesi,’ ‘Clementine,’ and ‘Yashar’) and four levels of salinity (control, 1, 3, and 5 dS/m) in three replications to explore the mechanism by which salinity stress affects photosynthetic and growth factors of mandarin cultivars. After applying salinity treatments, shoot fresh and dry weight, root fresh and dry weight, branch number, leaf number, plant height, leaf and root potassium (K), sodium (Na), and calcium (Ca) contents, chlorophyll content, proline content, leaf nitrogen, and protein content, electrolyte leakage, and sugar content were measured. The results showed that salinity stress reduced vegetative and photosynthetic factors in all three cultivars. Root and leaf K and Na contents, chlorophyll a, total chlorophyll, proline content, electrolyte leakage, and sugar and protein contents were affected by cultivars. Salinity affected root and leaf K and Na contents, chlorophyll a and b and total chlorophyll contents, proline, and electrolyte leakage significantly. The interaction of cultivar and salinity was also significant on chlorophyll a and total chlorophyll contents, leaf N and protein contents, and electrolyte leakage. Salinity stress reduced vegetative and photosynthesis factors of all three cultivars.

摘要

柑橘的生长通常受到盐度的限制，但柑橘砧木对盐度的反应不同。温室研究采用完全随机的设计，三个品种的柑橘（“Younesi”、“Clementine”和“Yashar”）和四个盐度水平（对照、1、3 和 5 dS/m）在三个重复研究盐胁迫对柑桔品种光合和生长因子的影响机制。施盐处理后的芽鲜干重、根干鲜重、分枝数、叶数、株高、叶根钾（K）、钠（Na）、钙（Ca）含量、叶绿素含量、脯氨酸测定叶氮含量、蛋白质含量、电解质渗漏和糖含量。结果表明，盐分胁迫降低了所有三个品种的营养和光合因子。根和叶 K 和 Na 含量，叶绿素a，总叶绿素、脯氨酸含量、电解质渗漏、糖和蛋白质含量受品种影响。盐分显着影响根和叶K和Na含量、叶绿素a和b以及总叶绿素含量、脯氨酸和电解质渗漏。品种和盐度的交互作用对叶绿素a和总叶绿素含量、叶片N和蛋白质含量以及电解质渗漏也有显着影响。盐胁迫降低了所有三个品种的营养和光合作用因子。