不同選擇性培養基偵測台灣十字花科蔬菜黑腐病菌之效率

Efficiency of Various Selective Media for Detection of Xanthomonas Campestris pv. Campestris in Taiwan

黃㯖昌(Tze-Chung Huang) ； 徐世典(Shin-Tien Hsu)

《臺東區農業改良場研究彙報》 2輯 (1988/06) Pp. 89-106

https://doi.org/10.6959/RBTDAIS.198806.0089

摘要

台灣黑腐病菌（Xanthomonas campestris pv. campestris）在SX agar，nutrient-starch-cycloheximide agar（NSCA），nutrient starch cycloheximide antibiotic agar（NSCAA），basal starch cychohemide antibiotic agar（BSCAA），starch methionine medium（SM）及soluble starch medium等六種現有之黑腐病菌選擇性培養基上之平板效率雖可達75%或更高，但這些培養基應用於偵測十字花科種子洗出液及土壤抽出液中之黑腐病菌時，其效果均不理想，其主要原因為各培養基上出現雜菌及拮抗菌之數目偏多，影響回收黑腐病菌之效率。這些培養基中，以DSX及NSCA培養基之效果最差，而其他四種培養基之表現隨土壤及種子樣品之不同而有很大差異，從土壤中之間收效率為2.2～17.7%，從種子上則為0～57.4%。自種子及土壤中常可分離到對黑腐病菌生長具抑制作用之拮抗細菌，其中屬於BaciIIas spp者在BSCAA，SM及SX培養基上不能生長，但屬於fluorescent pseudomonads者，多數之菌株在SX培養基上却具有極強之抑制黑腐病菌生長之能力，嚴重影響黑腐病菌之回收，在BSCAA及SM培養基上，尤其在SM培養基抑制力則極弱，對病菌回收之影響亦輕微，這些fluorescent pseudomonads拮抗細菌在選擇性培養基上之抑制能力與其產生之螢光色素無關，而可能起因於其他拮抗機制，由於黑腐病菌在SM培養基上最容易被鑑別，且其回收受拮抗細菌之影響最輕微，因此，SM培養基在六種供試培養基中表現最佳。

關鍵字

黑腐病菌 ； 選擇性培養基 ； 拮抗細菌 ； 偵測

並列摘要

Six available selective isolation media, i.e., SX agar, nutrient-starch-cycloheximide agar(NSCA), nutrient starch-cycloheximide antibiotic agar (NSCAA), basal nutrient cycloheximide antibiotic agar (BSCAA), starch-methionine medium (SM) and soluble starch medium (DSX) , were compared for their detection of Xanthomonas campestris pv. campestris (abbreviated to Xcc) in Taiwan. Although plating efficiencies of Xcc on these media were 75 % or higher, the recovery of Xcc from crucifer seed washings and soil extracts was very inefficient due to the appearance of high number of other bacteria including antagonistic bacteria on these media. Media DSX and NSCA were least effective among those tested. Recovery efficiencies of Xcc on the other four media varied with soil types and seed sources, ranged from 2.2 to 17.7 % from soil samples and 0 to 57.4% from seed samples. Bacillus spp. and fluorescent pseudomonads inhibitory to the growth of Xcc were frequently isolated from seeds or soils. Bacillus spp. did not grow on medium of BSCAA, SM or SX, but most strains of fluorescent pseudomonads strongly inhibited the growth of Xcc on SX agar and greatly reduced the recovery of Xcc when the antagonistic bacteria present. Fluorescent pseudomonads, however, were only slightly antagonistic to Xcc on SM and BSCAA media especially on SM medium, and also slightly reduced the recovery of xcc. The antagonism of fluorescent pigments, was not related to the formation of fluorescent pigments, but was possibly caused by other antagonistic mechanisms. SM medium performed best among the six selective media tested, since the colony of Xcc could be easily distinguished from other bacteria and the recovery of Xcc was less affected by the antagonists on the medium.

並列關鍵字

Xanthomonas campestris pv. campestris ； Selective media ； Antagonists ； Detection