甘藍根腫(瘤)病整合性管理技術之研究

Abstract

甘藍(Brassica oleracea L. var. capitata DC.)是臺灣蔬菜生產主要作物之一，其於平地秋季與山區夏季種植時，易受十字花科根腫(瘤)菌(Plasmodiophora brassicae Woronin)危害。十字花科根腫(瘤)病為全球性病害，在土壤pH 6-6.5、溫度20-25℃及土壤含水率高於70%時，易發生根部異常腫大、水分運輸受阻、導致地上部萎凋、死亡。本研究在位於海拔2100公尺之國立臺灣大學生物資源暨農學院附設山地農場梅峰本場無發病田間，種植臺灣甘藍主要栽培品種‘初秋’、‘228’、‘266’、‘綠秋’、‘高峰’、‘輝峰’、‘大型初秋’與‘鑫豐’，以及日本抗根腫(瘤)病品種‘夢いっぽ’、‘多惠’、‘理念’、‘フルーツキャベツ’、‘金剛’與‘月光’；‘228’之單株產量為834 g、‘初秋’ 581 g，種子發芽率分別為66.7%與100%；‘多惠’單株產量742 g，日本其他5抗病品種，然此6品種於總鹽類含量、總可溶性固形物含量與硬度皆無顯著差異。將‘228’、‘初秋’、‘理念’與‘多惠’兩週齡苗，分別移植至接種根腫(瘤)菌孢子0、105、106、107和108 spores per gram soil之土壤，在接種後10天均出現根毛感染情形、60天後根部皆出現根腫(瘤)病徵；而於根毛感染率與病害指數，‘228’與‘初秋’皆顯著高於‘理念’與‘多惠’。‘228’與‘初秋’於發芽後2週，每株澆灌綠生菌1號加6號1000倍稀釋液100 mL，之後每2週追施500倍稀釋液100 mL，植株病害指數皆為0%，病害控制效果達100%，顯著高於對照組。此外，於夏季在梅峰進行田間試驗，施用莊明堂農民栽培法，每分地施用蓖麻粕1200 kg、蝦蟹殼粉200 kg、礦石粉300 kg與鈣鎂肥200 k做為基肥，施用礦石粉50 kg為追肥，並以蘇利菌及苦楝油防治病蟲害，‘初秋’、‘228’、‘理念’與‘多惠’單株可販售葉球重分別為1118.8、576.7、587.0與461.4 g，比施石灰或綠生菌1號加6號者顯著提高。於春陽分場壽亭、前期作物為豌豆的10號田，種植‘228’、‘理念’和‘多惠’，同樣採用莊明堂農法，單畦7.5 m2葉球重(可販售葉球重 × 結球率 × n, n=17)分別為13.34、12.93和10.52 kg，病害指數分別為64.6%、56.3%和51.0%；‘初秋’施用綠生菌1號加6號，則單畦7.5 m2葉球重和病害指數分別是15.30 kg與62.5%。而於前期作物為南瓜的6號田，利用莊明堂農法種植‘理念’，單畦7.5 m2葉球重為16.91 kg、病害指數為56.3%。綜之，於罹病率低的田區，建議種植‘228’、‘初秋’、‘理念’或‘多惠’，於罹病率高的田間，則推薦種植‘理念’與‘多惠’，皆施以莊明堂農法，可作為防治甘藍根腫(瘤)病的參考。

Cabbage (Brassica oleracea L. var. capitata DC.) is one of the main vegetable crops in Taiwan. In autumn lowland and in summer highland, cabbage is frequently infected by Plasmodiophora brassicae Woronin which causes clubroot disease. This worldwide disease usually occurs at under soil pH 6-6.5, temperatures 20-25 ℃, and soil moisture content higher than 70%. After infection, cabbage root will swell, followed by difficulty in water transportation, wither and death of plants. Japanese resistant cultivars, ‘夢いっぽ’, ‘多惠’, ‘理念’, ‘フルーツキャベツ’, ‘金剛’ and ‘月光’, and Taiwanese dominant cultivars, ‘初秋’, ‘228’, ‘266’, ‘綠秋’, ‘高峰’, ‘輝峰’, ‘大型初秋’ and ‘鑫豐’, were planted in non-infective field at Meifeng headquarter, Highland Experimental Farm, National Taiwan University. Marketable yields and germination rates of ‘228’ and ‘初秋’, were 834 g per plant and 581 g per plant, 66.7% and 100%, respectively. ‘多惠’ had the marketable yield of 742 g per plant, which is significantly higher than those of other 5 Japanese cultivars. However, the salinity, total soluble solids and hardness of leafy heads among these 6 cultivars showed no significant difference. After transplanting 2-week-old seedlings of ‘228’, ‘初秋’, ‘理念’ and ‘多惠’ to infective soil with the inoculated rates of 0, 105, 106, 107 and 108 spores per gram soil, root hair infection and swollen roots could be observed on 10 and 60 days after inoculation, respectively. Besides, the root hair infection rates and disease indices were significantly higher in ‘228’ and ‘初秋’. For ‘228’ and ‘初秋’, 100 mL per plant diluent of 1000'×' Green Life Bacteria no.1 and no.6 on two weeks after germination, and afterward 100 mL per plant 500'×' diluent of Green Life Bacteria no.1 and no.6 twice a week, were applied to control clubroot disease. Disease indices and control rates were 0% and 100%, respectively, among all plants of ‘228’ and ‘初秋’. According to the cultural management of farmer Ming-Tang Zhuang, 1200 kg castor meal, 200 kg shell powder, 300 kg rock powder per acer and 200 kg calcium-magnesium fertilizer per acre were applied as basal fertilizers, 50 kg rock powder as additional fertilizer, and biological control pest by Bacillius thuningiensis and neem oil were applied per acre. The marketable yields of ‘228’, ‘初秋’, ‘理念’ and ‘多惠’ were 1118.8, 576.7, 587.0 g and 461.4 g per plant, respectively, which were significantly higher than those of liming or Green Life Bacteria no.1 and no.6 treatments. ‘228’, ‘理念’ and ‘多惠’ applied with cultural management of farmer Ming-Tang Zhuang in field no.10 where pea was the previous crop, head weights per 7.5 m2 per plot (marketable head weight × heading rate × n, n=17) were 13.34, 10.52 and 10.52 kg, respectively. As for ‘初秋’, 15.30 kg of head weight per plot was produced in the treatment of Green Life Bacteria no.1 and no.6. In field no.6 where pumpkin was the previous crop, planting ‘理念’ with Ming-Tang Zhuang’s cultural management showed 16.91 kg head weight per 7.5 m2. In conclusion, higher head weights per plot can be obtained in fields with lower disease index by growing ‘228’, ‘初秋’, ‘理念’ and ‘多惠’ with cultural management method of Ming-Tang Zhuang. For fields with higher disease index, ‘理念’ and ‘多惠’ were suggested to cultivate with the Ming-Tang Zhuang’s method.