Oustric Julie, Morillon Raphaël, Luro François, Herbette Stéphane, Martin Paul, Giannettini Jean, Berti Liliane, Santini Jérémie
CNRS, Laboratoire Biochimie and Biologie Moléculaire du Végétal, UMR 6134 SPE, Université de Corse, Corsica, France.
Equipe "Amélioration des Plantes à Multiplication Végétative", UMR AGAP, Département BIOS, CIRAD, Petit-Bourg, Guadeloupe.
Front Plant Sci. 2019 Feb 11;10:127. doi: 10.3389/fpls.2019.00127. eCollection 2019.
Plants require essential minerals for their growth and development that are mainly acquired from soil by their roots. Nutrient deficiency is an environmental stress that can seriously affect fruit production and quality. In citrus crops, rootstock/scion combinations are frequently employed to enhance tolerance to various abiotic stresses. These tolerances can be improved in doubled diploid genotypes. The aim of this work was to compare the impact of nutrient deficiency on the physiological and biochemical response of diploid (2x) and doubled diploid (4x) citrus seedlings: Volkamer lemon, Trifoliate orange × Cleopatra mandarin hybrid, Carrizo citrange, Citrumelo 4475. Flhorag1 ( + and willow leaf mandarin), an allotetraploid somatic hybrid, was also included in this study. Our results showed that depending on the genotype, macronutrient and micronutrient deficiency affected certain physiological traits and oxidative metabolism differently. Tetraploid genotypes, mainly Flhorag1 and Citrumelo 4475, appeared resistant compared to the other genotypes as indicated by the lesser decrease in photosynthetic parameters ( , / , and ) and the lower accumulation of oxidative markers (MDA and HO) in roots and leaves, especially after long-term nutrient deficiency. Their higher tolerance to nutrient deficiency could be explained by better activation of their antioxidant system. For the other genotypes, tetraploidization did not induce greater tolerance to nutrient deficiency.
植物生长发育需要必需矿物质，这些矿物质主要通过根系从土壤中获取。营养缺乏是一种环境胁迫，会严重影响果实产量和品质。在柑橘作物中，经常采用砧木/接穗组合来提高对各种非生物胁迫的耐受性。在双二倍体基因型中，这些耐受性可以得到改善。这项工作的目的是比较营养缺乏对二倍体（2x）和双二倍体（4x）柑橘幼苗（ Volkamer柠檬、三叶橙×埃及艳后橘杂交种、卡里佐枳橙、Citrumelo 4475）生理和生化反应的影响。本研究还包括异源四倍体体细胞杂种Flhorag1（+和柳叶橘）。我们的结果表明，根据基因型不同，大量元素和微量元素缺乏对某些生理性状和氧化代谢的影响也不同。四倍体基因型，主要是Flhorag1和Citrumelo 4475，与其他基因型相比表现出抗性，这表现为光合参数（ 、 / 、和 ）下降较小，以及根和叶中氧化标记物（MDA和HO）积累较低，尤其是在长期营养缺乏后。它们对营养缺乏的较高耐受性可以通过其抗氧化系统的更好激活来解释。对于其他基因型，四倍体化并未诱导对营养缺乏的更大耐受性。
