鲜菌草与干菌草栽培的香菇品质比较

以鲜菌草五节芒和干菌草五节芒栽培香菇,比较鲜、干菌草两种培养料中,菌丝体的形态结构、子实体的生长情况及培养料的生物学效率,并测定鲜、干菌草栽培所得的香菇子实体中水分、粗脂肪、粗蛋白、氨基酸、灰分和总糖等营养成分的含量及重金属含量.结果表明:鲜、干菌草培养料中,香菇菌丝体的形态差异明显,子实体生长情况相似;鲜菌草培养料的生物学效率高于干菌草;鲜菌草栽培的香菇子实体中粗脂肪、粗蛋白、灰分和氨基酸等4种营养成分的含量略低于干菌草栽培的香菇子实体,前者的总糖含量高于后者,重金属含量均在国家规定的范围内.因此,使用鲜菌草五节芒栽培香菇是可行的.

鲜菌草与干菌草灭菌前后碳氮含量及碳氮比

以鲜菌草(巨菌草、象草、五节芒)及其相对应的干菌草为试材,采用单因素试验方法,研究鲜菌草与干菌草灭菌前与灭菌后的碳氮含量及碳氮比的变化。结果表明:灭菌前,鲜菌草的碳含量低于相应干菌草的碳含量,鲜菌草的氮含量高于相应干菌草的氮含量,鲜菌草的碳氮比均低于相应干菌草的碳氮比;灭菌后,鲜菌草与干菌草的碳含量和氮含量均有所降低,除了干巨菌草以外,鲜菌草与干菌草的碳氮比均降低,鲜菌草的碳氮比也低于相应干菌草的碳氮比。因此,灭菌对鲜菌草和干菌草的碳含量、氮含量和碳氮比均有影响,鲜菌草更适合用于栽培较低碳氮比的食药用菌。

Mycelium Growth and Yielding of Black Poplar Mushroom-Agrocybe aegerita （Brig.） Sing. on Different Substrates

Mycelial growth and yield of two strains ofA. aegerita on different substrates was investigated. Mycelial growth on agar media （PDA, standard, wheat, MEA, CYM, PCA, sawdust extracts： alder and mixture of beech and birch （1：1）） and sawdust substrates （birch, beech, oak, maple, alder） was investigated. Petri dishes （Ф 9 cm） for agar media and biological tubes （18 cm long and Ф 2.5 cm） for sawdust substrates were used. Yield and morphological features were studied on birch, beech and mixture of beech and alder （1：1） sawdust substrates. The temperature of inoculation for agar media and sawdust substrates was 25 ℃. For yielding, when mycelium has completely overgrown the substrate the temperature was decreased to 15-17 ℃ to initiate primordia formation. The cultivation was enlightened 10 h/d with daylight lamps （500 Ix）. One crop was harvested after five weeks. The carpophores of black poplar mushrooms were picked up in clusters. There was no statistically important difference between the mycelial growths of the investigated strains. The best growing agar media were PDA （7.3 cm）, MEA （7.2 cm） and wheat （7.1 cm）, both strains showed the slowest mycelium growth on CYM （5.2 cm）. The mycelial growth on sawdust was the best on the beech （7.1 cm） and birch （6.8 cm） sawdust. The best substrate for cultivation ofA. aegerita was mixture of beech and alder sawdust （39.5 g/100 substrate DM）. The dry yield of carpophores were the highest on beech and alder substrate （3.2 g/100 substrate DM）, but dry matter content was the highest on beech sawdust （15.7%）. The heaviest carpophores were harvested from birch sawdust （3.7 g）; the biggest caps from beech and alder sawdust （3.3 cm）. There were no statistically important differences between the mycelium growth and yielding between both investigated strains.

Drought shifts soil nematode trophic groups and mediates the heterotrophic respiration

As the most diverse metazoan taxa,soil nematodes serve a diversity of functions in soil food webs and thus can regulate microbial community composition and affect organic matter decomposition and nutrient turnover rates.Because nematodes depend on water flms to access food resources,drought can negatively affect nematode-microbial food webs,yet the impacts of drought on nematode diversity and abundance and how these changes may infuence food web members and their functions are hardly explored.Here,we coupled research along a drought gradient in arid and semiarid grasslands with a detailed intact plant-soil microcosm experiment to explore the patterns and mechanisms of how drought impacts nematode abundance and carbon footprint,microbial phospholipid fatty acid(PLFA)and heterotrophic soil respiration.Overall,in the feld and the microcosm experiments,we found that nematode abundance,carbon footprint and diversity,microbial PLFA and heterotrophic respiration were reduced under drier conditions.In addition,drought altered nematode and microbial community composition,through reducing the nematode channel ratio and increasing the relative fungivorous nematode abundance and the fungal to bacterial ratio.The soil decomposition channel shifted from a bacterial to a fungal pathway in response to drought,indicating decelerated heterotrophic respiration under drought.These results highlight the important contribution of soil nematodes and their associated microbial food web to soil carbon cycling.Our fndings underscore the need to incorporate key soil fauna into terrestrial ecosystem model evaluation.