Study on screening of cellulose-decomposing microbial and inoculating on agricultural wastes compost

Peat is a common growth medium used for vegetable plug seedlings. In view of the decreasing output, using composted agricultural waste to replace part of the peat is one of the possible ways of providing an alternative medium. In this research, we screened a CY1 isolate with a strong cellulose decomposing ability, which was identified as Lichtheimia ramosa, a common microbial in the brewing industry obtained from several substrates. CY1 had optimal growth at pH 5-7, and both growth and cellulase activity were apparent at 40℃. In the experiment, CY1 was incubated in media in which different carbon and nitrogen sources and crop residues extract were added, and the growth of CY1 was inhibited significantly by urea and tomato plant residues extract. Spent mushroom substrates (SMS), bagasse and tomato plant residues (T) are common agricultural wastes in Taiwan. CY1 was added to these three kinds of material for composting. The center temperature of the SMS and bagasse composts were in general higher than the temprature of the control during the process, which showed that the microorganisms were more active. Due to the unsuitable pH and inhibitory action, there was no significant effect of T compost on CY1. After 12 weeks, the pHs of SMS and bagasse composts were approximately 6, while that of the T compost was over 8, and the electrical conductivity values of the three kinds of compost were lower than 500 μs/cm. Available Ca, K and Mg in the three composts increased with composting duration; however, the levels of micronutrients decreased in the T compost due to its high pH. Bagasse had the highest carbon-to-nitrogen ratio (203.24) of the three materials, followed by SMS and T (27.78 and 18.59, respectively), whereas all treatments led to a ratio of below 20 after composting. The water-holding capacities of SMS and T composts were lower than that of peat, while the physical properties of milled bagasse compost were similar to those of peat. Seedlings of cabbage 'peak' were grown in plugs with different media composed of the three composts mixed in different proportions with peat, and the greatest growth vigor was observed in media with a 100% proportion of the three kinds of compost. Seedlings exhibited a higher stem length, greater leaf area and greater shoot fresh weight when grown in T medium as compared with peat, but when grown in SMS and bagasse, the plants were smaller due to the lower nutrient content. If the irrigation and fertilization management strategies can be adequately adjusted, all three composts could be substituted for peat as a plug seedling medium.泥炭為蔬菜穴盤育苗上常用之介質，鑑於其日益稀少的產量，有必要尋找替代介質，將農業廢棄物經堆肥化處理製成可利用之介質為一可行方法。本研究自不同基質中篩選出具良好纖維分解能力之菌株CY1，經鑑定為傘枝黎頭霉(Lichtheimia ramosa)，為釀造工業中常見之菌種，適合生長於pH 5-7之弱酸性環境，在40℃時生長及纖維素酶活性最佳。於培養基添加不同碳氮源之測試中可得知尿素顯著抑制CY1生長，培養基添加不同植株殘體萃取液時觀察到番茄殘株會抑制其生長。 廢棄太空包之木屑、榨糖後之蔗渣與番茄栽培期間修剪之殘株為台灣常見農業廢棄物，將三種資材分別添加CY1菌液進行堆肥化作用，木屑與蔗渣堆肥堆積期間之中心溫度大多高於對照組，顯示其中微生物較活躍，而番茄殘株堆肥由於抑制菌株生長與不適當之pH，未有明顯效果。堆積12週後木屑與蔗渣堆肥之pH約為6，番茄殘株堆肥高達8以上，而EC值三種堆肥皆降至500 µs/cm以下。有效性鈣、鉀、鎂在三種堆肥中的含量大致隨堆積時間而增加，番茄殘株堆肥中之微量元素有效性因高pH而下降。原料之碳氮比以蔗渣的203.24為最高，其次為木屑27.78及番茄殘株18.59，經堆積後三種堆肥最終碳氮比皆低於20。堆肥成品之物理性質與慣用泥炭配方相較，木屑與番茄殘株堆肥保水力不佳，磨碎之蔗渣堆肥各性質與泥炭相近。將三種堆肥分別以不同比例與泥炭混合進行甘藍'高峰'之穴盤育苗，苗株於三種介質之生長狀況皆以100%堆肥的比例為最佳。與泥炭土栽培相較，番茄殘株堆肥之莖長、葉面積、地上部鮮重則較泥炭高，木屑與蔗渣堆肥則因肥份較少造成植株較小。如配合不同介質特性予以適當之灌溉管理與施肥調整，則此三種堆肥應可取代泥炭作為穴盤育苗之介質。摘要I Abstract II 目錄III 表次IV 圖次V 壹、前言1 貳、前人研究 一、農業廢棄物再利用2 二、堆肥化作用2 三、促進堆肥化之微生物7 四、無土栽培與理想介質特性7 参、材料與方法 一、纖維分解菌篩選11 二、以纖維分解菌製作堆肥13 三、以堆肥作為甘藍育苗介質16 四、統計分析16 肆、結果 一、纖維分解菌篩選17 二、以纖維分解菌製作堆肥18 三、以堆肥作為甘藍育苗介質22 伍、討論 一、纖維分解菌篩選43 二、以纖維分解菌製作堆肥46 三、以堆肥作為甘藍育苗介質48 陸、參考文獻50 柒、附錄5