摘要:2009~2010年從采自漾濞彝族自治縣的500份核桃根際土壤樣品中分離到3個(gè)屬18種捕食線(xiàn)蟲(chóng)真菌,其中檢出頻率較高的是Arthrobotrys musiformis和Monacrosporium thaumasium,檢出率分別為16.97%和12.96%。通過(guò)對(duì)四個(gè)季節(jié)捕食線(xiàn)蟲(chóng)真菌多樣性分析,發(fā)現(xiàn)夏季和秋季的物種多樣性指數(shù)較高,分別為2.38和2.35;其次是春季,為2.00;冬季的相對(duì)較低,為1.76。在所有檢測(cè)到的捕食線(xiàn)蟲(chóng)真菌中,產(chǎn)黏性網(wǎng)的捕食線(xiàn)蟲(chóng)真菌占77.78%。
關(guān)鍵詞:捕食線(xiàn)蟲(chóng)真菌;多樣性;核桃根際;漾濞彝族自治縣
中圖分類(lèi)號(hào):S436.64;Q949.32 文獻(xiàn)標(biāo)識(shí)碼:A 文章編號(hào):0439-8114(2011)19-3953-03
Diversity of Nematode-trapping Fungi in Walnut Rhizosphere at Yangbi County
YANG Xiao-yan,WANG Yan-lai,YANG Qing,XU Hai-long,L?譈 Zhi-hua,SU Hong-yan
(College of Agriculture and Biological Sciences, Dali University, Dali 671003, Yunnan, China)
Abstract: 500 soil samples were collected from walnut rhizosphere at Yangbi county in 2009 and 2010, and investigated for nematode-trapping fungi. 18 species which were assigned into 3 genera were isolated. Arthrobotrys musiformis and Monacrosporium thaumasium were dominant species, with their positive rate was 16.97% and 12.96%. The diversity of nematode-trapping fungi was higher in summer and autumn, as the diversity index was 2.38 and 2.35 respectively. The diversity index in winter was 1.76, which was lower than other seasons. The species forming adhesive nets were dominant, the positive rate of them was 77.78%.
Key words: nematode-trapping fungi; diversity; walnut rhizosphere; Yangbi Yi Autonomous county
捕食線(xiàn)蟲(chóng)真菌(nematophagous fungi)是以營(yíng)養(yǎng)菌絲特化形成捕食器官(trapping device)來(lái)捕食線(xiàn)蟲(chóng),在動(dòng)植物、水生植物及食用菌線(xiàn)蟲(chóng)生物防治中起重要作用的一類(lèi)真菌[1]。捕食線(xiàn)蟲(chóng)真菌在世界范圍廣泛分布,甚至在南極[2]、熱泉[3]和重金屬污染區(qū)[4]等極端環(huán)境中都有分布。凡是有線(xiàn)蟲(chóng)的地方都可能存在捕食線(xiàn)蟲(chóng)真菌。作為線(xiàn)蟲(chóng)天敵的捕食線(xiàn)蟲(chóng)真菌廣泛存在于自然界,對(duì)維持環(huán)境中線(xiàn)蟲(chóng)的種類(lèi)和數(shù)量平衡起著主要作用,是目前尚未被充分認(rèn)識(shí)和利用的一種寶貴的生物資源。
漾濞彝族自治縣位于云南省西部橫斷山中,全縣面積1 975 km2,其中98.4%是山地。氣候溫和,屬溫帶亞熱帶季風(fēng)氣候,年平均氣溫34.6 ℃,年降雨量1 043.7 mm,相對(duì)濕度72%;土地肥沃,物種豐富,適宜核桃生長(zhǎng),是著名的“中國(guó)核桃之鄉(xiāng)”[5]。目前對(duì)核桃根際土壤中捕食線(xiàn)蟲(chóng)真菌資源的調(diào)查研究尚屬空白,本實(shí)驗(yàn)通過(guò)對(duì)漾濞核桃根際土壤中捕食線(xiàn)蟲(chóng)真菌多樣性進(jìn)行研究,并分離、鑒定和保存捕食線(xiàn)蟲(chóng)真菌菌株,掌握了該菌的生存環(huán)境及所需條件,以期為陸生線(xiàn)蟲(chóng)生防菌劑的研究奠定基礎(chǔ)。……