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排序方式: 共有2894条查询结果,搜索用时 609 毫秒
91.
92.
多年生黑麦草高频再生体系的建立及优化 总被引:2,自引:2,他引:2
从外植体预处理方式、基本培养基、激素浓度等方面着手,对多年生黑麦草愈伤组织诱导、继代、不定芽分化及再生过程中的影响因素进行了研究,提高了再生频率。结果如下:切取胚端半粒种子,经75%乙醇处理1min,0.1%HgCl处理15min,在经无菌水清洗4~6次后接种方式较好;愈伤组织诱导培养基以MS+2,4—D 8.0 mg/L(或另添加甘露醇25 g/L)为佳;愈伤组织接种于MS+2,4—D 8.0mg/L+甘露醇25 g/L上进行1~2次继代后于NB+6—BA2.0 mg/L上进行分化;不定芽转接至MS+6—BA2.0 mg/L上进行扩繁或于1/2MS+NAA0.5mg/L+IAA0.5mg/L上进行生根。 相似文献
93.
Joseli da Silva Tatagiba Luiz Antonio Maffia Roberto W. Barreto Acelino C. Alfenas John C. Sutton 《Phytoparasitica》1998,26(1):8-19
Microbial isolates from living petals, petal residues and leaf residues of rose, and from laboratory collections, were evaluated
for control ofBotrytis cinerea in rose. In leaf residues artificially infested withB. cinerea, isolates of the filamentous fungiGliocladium roseum, FR136 (unidentified) andTrichoderma inhamatum reduced sporulation of the pathogen by >90%, other filamentous fungi were 25–90% effective, and those of yeasts and bacteria
were <50% effective. In artificially inoculated petal residues, no microbe reduced sporulation ofB. cinerea by >75%, but isolates ofCladosporium oxysporum and four yeasts were 51–75% effective, and three filamentous fungi, eight yeasts andBacillus subtilis isolates were 26–50% effective. Isolates ofT. inhamatum, C. oxysporum andG. roseum performed best againstB. cinerea among isolates evaluated in leaf residues naturally infested with the pathogen and indigenous microorganisms. Totals of ten
isolates of filamentous fungi (includingC. oxysporum andC. cladosporioides), two of yeasts and five ofBacillus subtilis completely prevented lesion production byB. cinerea in detached petals, and a further six isolates of filamentous fungi (includingG. roseum) and six yeasts were 90–99% effective. Isolates ofC. oxysporum, C. cladosporioides andB. subtilis, the most effective microorganisms againstB. cinerea in flower buds, reduced number of lesions in the range of 42–65% compared with 59–89% for à standard fungicide (vinclozolin).
It is suggested that application of leading antagonists Jo living rose leaves and flowers should optimize control of inoculum
production byB. cinerea when the tissues die. Optimal biocontrol of lesion production in flower buds requires a better understanding of the microenvironment
of petals. 相似文献
94.
Pietro Rocculi Emiliano Cocci Santina Romani Giampiero Sacchetti Marco Dalla Rosa 《Postharvest Biology and Technology》2009,51(3):371-377
The effects of both 1-MCP treatment of pineapples and packaging of their fresh-cut products with an alternative modified atmosphere (MA: 86.13 kPa N2O, 10.13 kPa O2 and 5.07 kPa CO2) on physiological and quality changes of these minimally processed products were investigated. Fresh-cut fruit treated or not with 1-MCP were packed in Air or in MA and were stored at 4 °C for 10 d. The following parameters were monitored during storage: ripening index; O2, CO2 and C2H4 in the package headspace; firmness and colour. Microbial spoilage of MP pineapple samples was also investigated and a mathematical model based on the Zwietering modified Gompertz equation was used to obtain growth parameters of mesophilic bacteria, yeasts and moulds.The results showed that 1-MCP treatment and MAP in a N2O enriched atmosphere had a positive combined effect on the inhibition of respiration and ethylene production of fresh-cut pineapple and on its softening delay, confirming previous findings about 1-MCP and N2O preservative effects on fresh-cut fruit quality. This combined effect was not extended to the ripening index and colour maintenance, as MAP at 86.13 kPa of N2O did not add any benefit to that of the 1-MCP treatment. From a microbiological point of view, N2O MAP extended the shelf-life of the products of 3–4 d by increasing the lag phase of microbial growth. 相似文献
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98.
Sousa Larissa Nascimento Batista Samira Pereira Silva Samara Santos da Silva Rômulo Fylipe Sarmento Wlysse Ferreira Mota Rinaldo Aparecido Brasil Arthur Willian Lima Amaku Marcos Feitosa Thais Ferreira Vilela Vinícius Longo Ribeiro 《Veterinary research communications》2022,46(2):507-515
Veterinary Research Communications - This study aimed to describe the transmission of T. gondii in naturally infected goats in the semiarid region of northeastern Brazil, through evaluating the... 相似文献
99.
The methanol and ethyl acetate extracts of the aerial parts of Cirsium tenoreanum, have been evaluated for their phytochemical constituents and antibacterial and cytotoxic properties. Three flavonoids, apigenin, quercetin-3-O-galactoside and kaempferol-3-O-ramnoside, were isolated. The ethyl acetate extract showed a good antiproliferative activity. 相似文献
100.
Schlemper SR Schlemper V da Silva D Cordeiro F Cruz AB Oliveira AE Cechinel-Filho V 《Fitoterapia》2001,72(1):73-75
The antibacterial effects of extracts obtained from Persea cordata stem bark, employed in Brazil to treat infectious diseases, were studied. The ethyl acetate fraction of the hydroalcoholic extract showed activity against pathogenic bacteria which may justify the popular use of the plant. 相似文献