叢枝菌根菌共生可緩解番茄鹽鹼逆境壓力

Abstract

叢枝菌根菌（arbuscular mycorrhizal fungus, AMF）為⼟壤益⽣真菌，可與⼤多數陸⽣植物建立共⽣關係，促進植物對⽔分及礦物質養分之吸收，此外，研究亦指出接種 AMF 能增進植物之逆境抗性，如鹽害抗性，然⽽，多數研究以澆灌鹽⽔的⽅式模擬⼟壤鹽害，AMF 共⽣對實際栽培在鹽（鹼）⼟的作物的影響仍有待探討；為貼近 AMF 應用於鹽（鹼）田區的情形，本研究於 2021 年⾄台南北門區之鹽鹼田區採集⼟壤，並鑑定⼟樣內 AMF 菌種，發現 Funneliformis mosseae為優勢 AMF 菌種之⼀ ，為了解接種 F. mosseae 對作物鹽鹼逆境脅迫的影響，我們選用⾼經濟產值作物 — 番茄，進⾏試驗規劃。首先評估 5 種番茄品系對 F.mosseae 之親和性，發現⽟⼥番茄與 F. mosseae 之親和性最佳，因此選用作為後續試驗的品系；⽽在鹽鹼逆境試驗發現，與未接種處理相比，接種 AMF 的植株在移植到鹽鹼⼟後，老葉外表型受損程度較低，光合作用指標 SPAD 較⾼，電解質滲漏率較低，抗氧化酵素抗壞⾎酸酶（Ascorbate peroxidase, APX）和過氧化氫酶（Catalase, CAT）活性顯著提升，⽽滲透調節物質脯胺酸和總可溶性醣含量較低，離⼦濃度量測結果顯示葉片中 Na+和Ca2+離⼦累積較少，此結果表示接種 F.mosseae 可緩解⽟⼥番茄的鹽鹼逆境脅迫，使植株維持較佳的光合作用率與抗氧化能⼒，進⽽有較⾼產量 。本試驗揭露 F. mosseae 對活化鹽鹼田區作物栽培之潛⼒，可推廣作為微⽣物肥料，以友善環境的⽅式提升⼟地的利用價值。

Arbuscular mycorrhizal fungus (AMF) is a kind of beneficial fungi which can form symbiosis with plants, facilitating the absorption of water and mineral nutrient for host plants. Besides, some reports pointed out that AMF could also enhance host resistance to abiotic stress, like salinity. However, in most studies, saline water was provided to mimic the salinity condition. There were few researchers using saline-alkaline soil to conduct AMF-associated experiments. Therefore, the effects of AMF on crop growth in saline-alkaline environment await for further characterization. In 2021, we went to a saline-alkaline field in Beimen district, Tainan and find out the AMF species Funneliformis mosseae enriched in the rhizosphere part of it. We hypothesized that F. mosseae can help crops to alleviate the saline-alkaline stress. First, we tested the compatibility of five different tomato cultivars to F. mosseae, which found that the cultivar “Yu-nu” showed the best mycorrhizal growth response (MGR), used for further experiments. Under saline-alkaline condition, the SPAD value, antioxidant APX, CAT, POD, and chlorophyll fluorescence indicator Y(II) were significantly increased, and osmolyte content like proline and total soluble sugar were decreased in AMF-colonized plants, compared to mock-treated ones. Our results indicated that the inoculation of F. mosseae alleviates the saline-alkaline stress in tomato and increased the fruit production. Through our studies, we see the potential of AMF inoculation on tomato under saline-alkaline conditions which is good for the development of sustainable agriculture