Alquichire-Rojas Shirley, Escobar Elizabeth, Bascuñán-Godoy Luisa, González-Teuber Marcia
Facultad de Ciencias, Universidad Católica de la Santísima Concepción, Concepción, Chile.
Departamento de Botánica, Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Concepción, Chile.
Front Plant Sci. 2024 Aug 26;15:1386234. doi: 10.3389/fpls.2024.1386234. eCollection 2024.
Root-associated fungal endophytes may facilitate nitrogen (N) absorption in plants, leading to benefits in photosynthesis and growth. Here, we investigated whether endophytic insect pathogenic fungi (EIPF) are capable of transferring soil N to the crop species . We evaluated nutrient uptake, carbon allocation, and morpho-physiological performance in in symbiosis with two different EIPF ( and ) under contrasting soil N supply. A controlled experiment was conducted using two plant groups: (1) plants subjected to low N level (5 mM urea) and (2) plants subjected to high N level (15 mM urea). Plants from each group were then inoculated with different EIPF strains, either (EIPF1+), (EIPF2+) or without fungus (EIPF-). Differences in N and C content, amino acids, proteins, soluble sugars, starch, glutamine synthetase, glutamate dehydrogenase, and physiological (photosynthesis, stomatal conductance, transpiration), and morphological performance between plant groups under each treatment were examined. We found that both and translocated N from the soil to the roots of , with positive effects on photosynthesis and plant growth. These effects, however, were differentially affected by fungal strain as well as by N level. Additionally, an improvement in root C and sugar content was observed in presence of EIPF, suggesting translocation of carbohydrates from leaves to roots. Whereas both strains were equally effective in N transfer to roots, seemed to exert less demand in for photosynthesis-derived carbohydrates compared to . Our study revealed positive effects of EIPF on N transfer and morpho-physiological performance in crops, highlighting the potential of these fungi as an alternative to chemical fertilizers in agriculture systems.
与根相关的真菌内生菌可能有助于植物吸收氮（N），从而对光合作用和生长产生益处。在此，我们研究了内生昆虫病原真菌（EIPF）是否能够将土壤中的氮转移到作物物种中。我们评估了在两种不同的EIPF（ 和 ）共生条件下，以及在不同土壤氮供应情况下，植物的养分吸收、碳分配和形态生理表现。使用两个植物组进行了对照实验：（1）处于低氮水平（5 mM尿素）的植物和（2）处于高氮水平（15 mM尿素）的植物。然后，每组植物接种不同的EIPF菌株，即 （EIPF1+）、 （EIPF2+）或不接种真菌（EIPF-）。检测了各处理下植物组之间在氮和碳含量、氨基酸、蛋白质、可溶性糖、淀粉、谷氨酰胺合成酶、谷氨酸脱氢酶以及生理指标（光合作用、气孔导度、蒸腾作用）和形态表现方面的差异。我们发现 和 都能将土壤中的氮转移到 的根部，对光合作用和植物生长产生积极影响。然而，这些影响受到真菌菌株以及氮水平的不同影响。此外，在存在EIPF的情况下，观察到根部碳和糖含量有所改善，这表明碳水化合物从叶片转移到了根部。虽然两种菌株在向根部转移氮方面同样有效，但与 相比， 在对光合作用衍生的碳水化合物需求方面似乎较低。我们的研究揭示了EIPF对作物氮转移和形态生理表现的积极影响，突出了这些真菌在农业系统中作为化学肥料替代品的潜力。
