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F. López-Valdez F. Fernández-Luqueño J.M. Ceballos-Ramírez R. Marsch V. Olalde-Portugal L. Dendooven 《Scientia Horticulturae》2011
Preliminary studies showed that a Bacillus subtilis strain stimulates plant growth. We investigated how inoculating seeds of a sunflower cultivar (Helianthus annuus L.) with this strain stimulated plant growth, soil properties and emissions of greenhouse gasses, i.e. carbon dioxide (CO2) and nitrous oxide (N2O), when cultivated in a greenhouse. Unfertilized sunflowers or fertilized with urea served as controls. After one month, root length and fresh and dry root weight of the sunflower was significantly higher in the bacteria amended plant than in the urea and unfertilized plants. However, at harvest, no positive effect was observed. The number of seeds per plant and seed weight was not significantly different between the treatments, but total plant N was significantly higher in urea-amended plants than in unfertilized plants. The CO2 production rate was not affected by treatment, but the N2O emission rate was significantly higher in soil amended with urea plus bacteria soil compared to the unfertilized treatments. It was found that the B. subtilis strain used in this study had a positive, but only temporarily effect on growth of the sunflower cultivar used. 相似文献
64.
P. S. Shanmugam R. Balagurunathan N. Sathiah N. G. V. Rao 《Journal of pest science》2007,80(3):175-181
Cotton bollworm, Helicoverpa armigera Hubner selected for five generations with Bacillus thuringiensis insecticidal crystal protein Cry1Ac in the laboratory developed 12.98-fold resistance. Resistance and susceptible populations
were mass crossed to study the dominance of resistance. The Cry1Ac—selected (BCR) population showed 5.8-fold resistance to
Cry1Aa and 5.04-fold resistance to Cry1Ab. The degree of dominance (D) was 0.34 and 0.40 for the R × S and S × R hybrids, respectively, which indicates incomplete recessive character of Cry1Ac resistance in the population. The estimated
realized heritability (h
2) and response quotient (Q) of resistance for Cry1Ac were 0.52 and 0.15, respectively. This indicated the lower phenotypic variation in the selected
population. The resistance risk assessment based on h
2 indicated that the resistance would increased tenfold after <9 generations for Cry1Ac in the resistant population. The results
show the ability of H. armigera to develop resistance against Cry1Ac and cross-resistance to Cry1Aa and Cry1Ab. 相似文献
65.
Agricultural productivity may be raised in a sustainable way by many different technologies such as biological fertilizers,
soil and water conservation, biodiversity conservation, improved pest control, and changes in land ownership and distribution.
Of these measures, biotechnology applications probably hold the most promise in augmenting conventional agricultural productivity,
because biotechnology applications give not only the need to increase production, but also protect the environment and conserving
natural resources for future generations. Biotechnology applications will have the possibilities to increase productivity
and food availability through better agronomic performance of new varieties, including resistance to pests; rapid multiplication
of disease-free plants; ability to obtain natural plant products using tissue culture; diagnosis of diseases of plants and
livestock; manipulation of reproduction methods increasing the efficiency of breeding; and the provision of incentives for
greater participation by the private sector through investments. Insect resistance through the transfer of a gene for resistance
fromBacillus thuringiensis (Bt) is one of the most advanced biotechnology applications already being commercialized in many parts of the world. This paper
reviews the development and the status ofBt technology and application ofBt transgenic plants in current agriculture, and discusses specific issues related to the transfer of the technology to the
future of genetic engineered trees with emphasis on conifers.
Biography: Tang Wei (1964-), male, Ph. Doctor, Research associate, Department of Biology, Howell Science Complex, East Carelina University,
Greenville, NC 27858-4353, USA.
Responsible editor: Chal Ruihai 相似文献
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本研究对采自贵州林区中的响叶杨(Populusadenopoda Maxim)腐朽木和白蚁(Odontotermes formosanus(Shiraki))进行分离培养,分离自杨树腐朽木的产纤维素酶菌株为木霉属康宁木霉(Trichodermakoningii Oud);分离自白蚁肠的产纤维素酶菌株为芽孢杆菌属(Bacillus sp.)。对所分离的两个菌株进行滤纸降解观察与测定。所分离的菌株(Trichoderma koningii Oud.)滤纸培养30天后,有菌丝生长,培养基浑浊,滤纸呈絮状,培养7天后该菌对滤纸降解强度为7.13%(校正值)。刚果红法初步证明该菌能产纤维素酶。从白蚁肠分离的菌株(Bacillus sp.)滤纸培养15天后,滤纸呈絮状,培养基变浑浊,有细菌菌体沉积;培养7天后,对滤纸的降解强度为8.18%(校正值)。刚果红法初步证明该菌能产生纤维素酶。用五种培养基质培养芽孢杆菌属(Bacillus sp.)菌株,并测定其生长量,其中以滤纸为主要基质的培养液中,最高可检测到0.3×107cfu/ml菌株量。 相似文献
68.
采用砂土管和滤纸片两种保藏方法,对分属31个亚种的61株有代表性的苏云金芽孢杆菌经过1-23年保存后的菌体存活情况,形态特征及对林业主要害虫舞毒蛾幼虫的杀虫活性进行了试验,并对苏云金芽孢杆菌5个亚种的标准菌株和保存不同年限后的11项生理生化特性及酯酶型进行了测定。 相似文献
69.
许多不同的技术可以促进农业生产力的持续增长,生物技术是其中最重要和最有前途的方法。因为生物技术不仅可以增加生产力。而且在环境和自然资源的保护中起重要作用,应用生物技术可以生产高产、优质、高抗性和无病植物,同时也可以提高育种效率和促进食品的工业化生产。苏云金杆菌抗虫基因是目前生物技术领域中应用最广泛的例子之一。由此而产生的抗虫植物正在广泛应用于世界各地的商业化生产。本文综述了苏云金杆菌抗虫基因的研究进展和它在未来林木遗传工程中的应用。表4参68。 相似文献
70.
6~(-(2))菌是一株昆虫病原芽孢杆菌。经测定血清型是苏云金杆菌(Bacillus thuringensis)变种中的H_1血清型,酯酶型与已描述过的所有苏云金杆菌变种的酯酶型不同,具有特异性,是一个新的酯酶型。 相似文献