土壤有機質含量與土壤含水量對馬鈴薯瘡痂病影響研究初報

Preliminary studies on effect of soil organic matter and volumetric water content on the severity of potato common scab

蔡孟旅(Tsai, M. L.) ； 吳雅芳(Y. F. Wu) ； 吳盈慧(Y. H. Wu) ； 潘佳辰(C. C. Pan)

《臺南區農業改良場研究彙報》 79期 (2022/07) Pp. 57-66

摘要

馬鈴薯瘡痂病是遍及全球的病害，於馬鈴薯主要產區不同田區之間發病嚴重程度差異頗大。為初步了解不同土壤環境因子對臺灣瘡痂病罹病度之影響，本研究2014～2015年間主要於雲林縣斗南鎮及少數種薯驗證田區共20個採樣點，於馬鈴薯生長中期調查根圈土壤電導度、酸鹼值、有機值含量、有效性磷、鉀、鈣、鎂含量等土壤性質，並於薯塊成熟時調查馬鈴薯瘡痂病罹病度。將數據進行線性迴歸分析後，結果顯示斗南地區主要為安定系及本廳系坋質壤土中之馬鈴薯瘡痂病，在有機質含量介於1.75～3.53%時，土壤中的有機質含量與馬鈴薯瘡痂病罹病度間具正相關性（R^2=0.7），而其餘土壤性質對瘡痂病罹病度的影響在本次調查中均不具相關性。測試不同土壤含水量對瘡痂病罹病度的影響顯示，若栽培介質之含水量（VWC）維持在12～20%時，瘡痂病罹病度最為嚴重（100%）；若維持在33～40%，也就是較濕潤的狀態下，罹病度較低（70.8±7.2%），未接種病原之對照組則為0%，三處理間均具極顯著之差異（P<0.0001）。本研究之初步試驗結果顯示，於結薯期增加灌溉次數保持田土濕潤，並避免田土濕度之劇烈變化，可能對馬鈴薯瘡痂病而言為一有效之耕作防治措施。現有技術：馬鈴薯瘡痂病尚無登記用藥，土壤傳播性病害亦難以藥劑防治。創新內容：研究初步調查結果顯示斗南地區安定系及本廳系坋質壤土有機質含量與馬鈴薯瘡痂病罹病度間具正相關性，而盆栽試驗顯示於結薯期維持土壤濕潤狀態，其馬鈴薯瘡痂罹病度較低。對產業影響：於結薯期增加灌溉次數保持田土濕潤，可能對馬鈴薯瘡痂病而言為一有效之耕作防治措施。本研究提供降低馬鈴薯瘡痂病罹病度之耕作防治建議，以期能維護馬鈴薯品質。

關鍵字

馬鈴薯瘡痂病 ； 土壤有機質含量 ； 土壤含水量

並列摘要

Potato common scab is an important disease around the world. Disease severity varied in different locations. We conducted a preliminary studies on the effect of different soil properties, such as rhizosphere soil EC, pH value, organic matter, effective phosphorus, potassium, calcium, and magnesium on the disease severity of common scab on potato tubers. Experiments were conducted of 20 locations between 2014 and 2015 in Dounan, Yunlin county. Results showed that the percentage of soil organic matter to disease severity was positively correlated (R^2 = 0.7), but other soil properties were not correlated. Highest disease severity (100%) was observed in the soil with 12-20% of volumetric water content (VWC). If the VWC increased to 33-40%, severity was lowered to (70.8 ± 7.2 %), and no scab was observed in the non-inoculated control (CK). This studies suggest that reasonable use of organic fertilizer and control of soil moisture during tuber formation stage could used as an cultural practice of the control of potato common scab. What is already known on this subject? No effective bactericide is available to control potato common scab disease. What are the new findings? This is the first report of soil moisture or VWC was used to control potato common scab. Thus, farmer's income can be increased. What is the expected impact on this field? Results of this study can be used as an effective cultural practice to control potato common scab without the use of bactericide.

並列關鍵字

Potato common scab ； Soil organic matter ； Soil volumetric water content