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991.
真菌及混合菌对玉米秸秆类腐殖质形成和转化的影响 总被引:3,自引:2,他引:1
针对3类真菌(木霉、黑曲霉和青霉)及混合菌在液体培养条件下对玉米秸秆类腐殖质形成和转化的影响,重点研究接种后秸秆类腐殖质组成的变化情况,以期为秸秆的生物降解、转化与土壤有机质的形成、更新提供理论参考和依据.结果表明:(1)接种可迅速减少代谢液和增加菌体-秸秆残留物的含碳量,随菌体繁殖,代谢液中含碳量持续降低,随后,降解作用促使小分子进入代谢液使其碳量增加,后期呼吸作用显著,代谢液碳量再度降低.此外,残留物可被黑曲霉和混合菌有效降解,木霉和青霉在培养初期的较强繁殖能力使残留物中碳量先增加,后又被降解.(2)培养初期,木霉、青霉和混合菌对残留物中有机碳组分的降解使小分子物质进入WSS(水溶性物质),随后菌体的繁殖迫使WSS再度降低,而黑曲霉则以利用WSS合成其自身组分为主.(3)起初,FLA(类富里酸)的形成速度大于HLA(类胡敏酸),而后FLA逐渐向HLA转化,木霉处理HLA在类腐植酸中所占比例最大.(4)培养过程中,FLA分子向简单化方向发展,而HLA分子先简单,而后渐变复杂.HLA单位碳芳香环的缩合程度随培养进行先逐渐降低而后增大,总趋势为增大,木霉处理HLA的复杂程度最高.(5)残留物HLu(类胡敏素)的碳含量在整个培养过程中先增高后降低,最终均有“净损失”,损失最大的为木霉处理. 相似文献
992.
喻初权 《湖南农业大学学报(自然科学版)》1999,25(6):458-460
为探寻稻草高产栽培木耳的技术,进行了经特殊处理的4种规格的稻草丝和5种其他原料,以及不同规格的栽培容器和不同出耳管理方法栽培木耳的试验。结果表明,以20mm×50mm筛孔粉碎机处理的稻草丝为原料,用规格的为17cm×33cm聚乙烯代为栽培容器,并采用覆土加施丰产素进行出耳管理,栽培木耳可获得高产。 相似文献
993.
994.
从香料植物天竺葵上分离筛选到一株产香真菌,对该菌株进行鉴定,确定其分类地位,并克隆其产脂肪酶基因进行序列分析。结果表明,分离筛选得到的菌株TZK-1形态为菌落圆形,质地疏松,菌丝由白色变为灰褐色,菌丝无隔膜,有假根,孢囊梗基部膨大形成球形孢子囊,孢囊孢子椭圆形;该菌株18S r DNA序列与米根霉Rhizopus oryzae(KF717370)相应片段的核苷酸序列同源性为99.6%。利用PCR扩增得到脂肪酶基因,该基因编码区全长为1 108 bp,编码369个氨基酸,脂肪酶核苷酸序列与推导的氨基酸序列与Rhizopus oryzae(AF229435)和Rhizopus oryzae(JN689988)聚为一支,支持强度分别达到92%和95%。结合形态学初步确定,产生浓郁甜酒香味的菌株为米根霉,能产生脂肪酶,克隆其脂肪酶基因全长。 相似文献
995.
996.
Martin M. Kulik 《European journal of plant pathology / European Foundation for Plant Pathology》1995,101(6):585-599
Cyanobacteria (blue-green algae) and eukaryote algae occur in freshwater, marine, and terrestrial (soil) habitats. In fact, these microorganisms comprise most of the world's biomass. Although the cyanobacteria are mostly photoautotrophic, some are facultative heterotrophs, capable of growing on certain substrates in darkness. Also, some are non-phototrophic and hence, are obligate heterotrophs. A number of cyanobacteria and eukaryote algae, particularly macroalgae, produce various, biologically active compounds. These include antibiotics which in laboratory tests inhibited bacteria and fungi that incite diseases of humans. In addition, the following fungi which are of interest to plant pathologists, were inhibitedin vitro by substances produced by various cyanobacteria: The saprophytesChaetomium globosum, Cunninghamella blakesleeana, andAspergillus oryzae and the plant pathogensRhizoctonia solani andSclerotinia sclerotiorum. Extracts from seaweeds (macroalgae) sprayed on plants have been reported to reduce the incidence ofBotrytis cinerea (gray mold) on strawberries,Erysiphe polygoni (powdery mildew) on turnips, and damping-off of tomato seedlings. Because many cyanobacteria and algae produce a large number of antibacterial and antifungal materials, are almost never a threat to the environment, and many can be grown in quantity in mass culture, they are suitable candidates for exploitation as biocontrol agents of plant pathogenic bacteria and fungi. Much additional work remains to be done however, to thoroughly evaluate cyanobacteria and algae and their products for this role. 相似文献
997.
Hitoshi?KawamataEmail author Kazuhiko?Narisawa Teruyoshi?Hashiba 《Journal of General Plant Pathology》2004,70(2):131-138
Rice phylloplane fungi were evaluated for their potential as biocontrol agents for rice blast disease caused by Magnaporthe grisea. A total of 1923 fungal isolates were obtained from rice plants in fields at Ishigaki and Iwama and from potted plants placed in a cedar woods in Iwama as bait. Although 82.9% of isolated fungi could not be identified, species of Epicoccum were the most prevalent among identified isolates. Of the 1923 isolates, 967 were randomly selected for screening against rice leaf blast. Nine isolates (MKP5111B, MKP5112, J2JMR3-2, K2J131-2, I5R3-1, NOP541, K1KM134-1, NOP5112, MKP33222) suppressed the disease when a conidial or hyphal suspension of both the phylloplane fungus and pathogen were simultaneously used to inoculate rice plants cultured in pots in a growth chamber. Five of the isolates originated from potted plants in the woods and four from Ishigaki, a subtropical island. Five (MKP5111B, MKP5112, NOP541, NOP5112, MKP33222) of the nine isolates strongly suppressed conidial germination of M. grisea (0.7%) and formed inhibition zones (3–5mm width) in dual cultures with the pathogen. Methanol extracts from the isolates also inhibited mycelial growth of the pathogen. These results suggest that the five isolates produced antibiotic(s). These five isolates are likely identical or closely related fungal species because the sequence of their ITS regions were 100% similar. ITS sequence analysis also suggested that J2JMR3-2 was associated with a species of Fusarium. Under field conditions, J2JMR3-2 reduced both leaf and panicle blast severity, and three other isolates (MKP5111B, K1KM134-1, K2J131-2) suppressed leaf blast in one of the three experiments. 相似文献
998.
嗜线虫真菌Duddingtonia flagrans防制绵羊胃肠道线虫病 总被引:2,自引:0,他引:2
将 30只 4~ 6月龄羊分为 2组 ,分别在各自的围栏草场中放牧。用毛圆线虫和血矛线虫为主的第 3期幼虫对所有羊只人工感染 2次后 ,一组羊按每千克体重 1× 10 6 个的剂量每天饲喂嗜线虫真菌的厚垣孢子制剂 ;另一组羊作对照 ,仅饲喂等量的上述制剂基质——小麦。第 2次人工感染后 8周 ,2组羊粪便 EPG基本相近 ,但与对照组相比较 ,真菌组粪便培养物中感染性幼虫减少了 6 9.7% ;草场草样中感染性幼虫数也较对照组减少 6 7.8%。再把以上 2组羊驱虫后分别放养于上述围栏草场 ,8周后真菌组羊粪便 EPG较对照组减少 87.3% ;草场感染性幼虫也较对照组减少82 .6 %。上述结果显示 ,嗜线虫真菌 Duddingtonia flagrans在绵羊胃肠道寄生性线虫病生物防制中具有良好的应用前景 相似文献
999.
对捕食线虫性真菌——少孢节丛孢菌(Arthrobotrys oligospora)菌株体外粪便捕杀马寄生性线虫幼虫进行了研究。结果表明:菌株可以在体外粪便中发育并发挥其捕食作用。在实验室条件下,其对寄生性线虫第一、二期幼虫的作用与对第三期幼虫的作用相比较.捕获致死速度快。菌株对马粪便中线虫幼虫的杀虫率高达98.7%;与对照组相比有显著差异。而且加入粪便的分生孢子数量在达到一定阈值后,再加入分生孢子,则杀虫率不再增加。此结论对捕食线虫性真菌今后临床的应用具有实际指导意义。 相似文献
1000.
Role of bioinoculants in development of salt-resistant saplings of Morus alba (var. sujanpuri) in vivo 总被引:1,自引:0,他引:1
Pot experiments were conducted for the development of salt-resistant saplings of Morus alba (var. sujanpuri) involving bioinoculants, namely arbuscular mycorrhizal (AM) fungi, Azotobacter and indole butyric acid (IBA). The IBA and sodium chloride (NaCl) concentrations were optimized prior to the experiments. By using both low and high concentrations, 15 ppm IBA and 0.05% NaCl (w/v) were found to be optimum in acting synergistically with AM fungi and Azotobacter and also for increasing all the growth parameters and microbial count in the rhizosphere. For in vivo development of salt-resistant saplings, the optimal concentration of IBA, along with AM fungi and Azotobacter in different combinations, was applied. The saplings were irrigated regularly with 0.05% NaCl water. Although growth parameters such as AM infection percentage, AM spores per 100 g soil and Azotobacter cells/g soil were affected by NaCl watering, the inoculation of both bioinoculants significantly enhanced survival percentage of saplings from 25 to 50% under salt stress. Maximum survival (55%) of saplings was found with IBA (15 ppm)+AM fungi+Azotobacter. 相似文献