接種促進植物生長微生物對番茄鹽鹼逆境耐性之影響

Abstract

農業的不當灌溉和過度抽取地下水，導致土壤鹽鹼化問題日漸嚴重，影響作物生長與生產。前人研究指出，施用有益植物生長的土壤微生物，如叢枝菌根菌（arbuscular mycorrhizal fungi，AMF）和促進植物生長細菌（Plant Growth Promoting Bacteria，PGPB），可促進植株生長勢、增強植物對逆境的耐受性，進而提高產量。本研究欲評估從鹽鹼田分離之叢枝菌根菌與從狼尾草分離之耐鹽細菌對番茄鹽鹼耐受性的影響；首先評估不同品種番茄與三種源自鹽鹼土的AMF之間的親和性，選擇花蓮亞蔬21號與 Albahypha sp.的組合在鹽鹼逆境下進行試驗，結果顯示接種Albahypha sp.可提升番茄在逆境生長的光合效率和抗氧化酵素活性；進一步測試耐鹽鹼內生菌Kocuria sp. Pp13和Bacillus aryabhattai Pp16與AMF共接種於番茄對逆境耐受性的影響，結果顯示植株僅接種Pp13和Pp16的處理對生長勢和逆境指標明顯優於對照組和AMF處理，比較接種Pp13、Pp16的單一和複合菌種接種處理試驗，結果發現，所有接種處理在株高和地上部鮮重均顯著高於對照組，且單一菌種的效益比複合接種佳，此外，不同PGPB處理的葉片荷爾蒙濃度存在差異，暗示不同菌株促進番茄抵禦逆境的機制各異，意外的是，接種處理的植株在逆境下生長較佳，但鈉離子吸收量明顯大於對照組。本研究發現不同微生物組合對番茄在鹽逆境下的生長和逆境耐受性的影響明顯不同，其中單獨接種Pp13和Pp16對番茄逆境耐受性的效益顯示這二隻菌株作為微生物肥料及土壤改良劑開發的潛力。

Improper irrigation and excessive groundwater extraction have exacerbated soil salinization, leading to the reduction of crop growth and production. Previous studies have demonstrated that the application of plant growth promoting microorganisms, such as arbuscular mycorrhizal fungi (AMF) and plant growth promoting bacteria (PGPB), can enhance plant growth, improve stress tolerance, and consequently increase yield. This study aims to evaluate the effects of inoculation with AMF isolated from saline-alkaline fields and salt-alkali tolerant bacteria isolated form Pennisetum purpureum Schumach on tomato growth under the saline-alkaline stress. First, we tested the affinity between five different tomato cultivars and three AMF strains derived from saline-alkaline soil. Based on the results of evaluation, Albahypha sp. and Hualien-Yasu No.21 was selected for further experiments. The results showed that inoculation with Albahypha sp. increased the photosynthesis efficiency and the peroxidase activity of Hualien-Yasu No.21 when growing under saline-alkaline conditions. We also tested the effects of co-inoculation with salt-alkali tolerant endophytic bacteria Kocuria sp. Pp13, Bacillus aryabhattai Pp16 and Albahypha sp. on saline-alkaline stress tolerance of tomatoes. We found that tomatoes treated with Pp13 and Pp16 exhibited better growth and stress tolerance compared to mock, AMF only and co-inoculation treatments. Moreover, we also noticed that plants inoculated with either Pp13 or Pp16 performed better than double inoculation treatment under stress conditions. Additionally, variations in leaf hormone concentrations between different PGPB treatments suggested that the involvement of phytohormone-mediated stress tolerance was varied by PGPB strains. Surprisingly, Pp13- and Pp16-inoculated tomatoes with better stress tolerance accumulated higher amount of sodium ions in leaves compared to mock-treated plants. In conclusion, our study showed the effects of different microbial combinations on tomato growth and saline-alkaline tolerance and the great potential of Pp13 and Pp16 for development as microbial fertilizers and soil amendments.