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921.
Nacira Muñoz Maria Eugenia Soria-Díaz Hamid Manyani Rocío Contreras Sánchez-Matamoros Antonio Gil Serrano Manuel Megías Ramiro Lascano 《Biology and Fertility of Soils》2014,50(2):207-215
The establishment of a symbiotic interaction involves a signal exchange between the host legume (flavonoids) and the nitrogen-fixing rhizobia (nodulation factors (NFs)). Likewise, abiotic stress conditions, such as salinity and drought, strongly reduce the nodulation process, possibly affecting also the signal exchange. In this work we characterized the structure and biological activity of NFs produced by Bradyrhizobium japonicum USDA 138 under control, salt, and osmotic stress conditions. This strain is the most widely used in Argentine soybean culture; under control conditions, it produces a mixture of four types of NFs (V(C16:0,MeFuc), V(C18:1,MeFuc), IV(C18:1), and V(C18:1,Ac,MeFuc)). Interestingly, under stress conditions, this strain produces new types of NFs, one common for both stress conditions (V(C16:1,MeFuc)) and another one only present under salt stress (IV(C18:1,MeFuc)). All mixtures of NFs, extracted from control, salt, and osmotic stress conditions, showed biological activity in soybean plants, such as root hair deformation, and the radical application of purified NFs induced systemic differences in dry matter accumulation. The inoculation of soybean with genistein-induced bacteria cultured under both control and stress conditions had a positive effect on the number of nodules formed and in some cases on dry matter accumulation. These responses are not related to changes in chlorophyll fluorescence or greenness index. 相似文献
922.
923.
Eberhardt Diogo Marchão Robélio Quiquampoix Hervé Le Guernevé Christine Ramaroson Volaniaina Sauvadet Marie Muraoka Takashi Becquer Thierry 《Journal of Soils and Sediments》2021,21(2):1024-1037
Journal of Soils and Sediments - Phosphorus (P) is often the main limiting factor for plant growth in highly weathered tropical soils. Phosphate use efficiency and crop yields could be increased in... 相似文献
924.
Kim Soon-Oh Jeong Jin Young Lee Woo-Chun Yun Seong-Taek Jo Ho Young 《Journal of Soils and Sediments》2021,21(8):2755-2769
Journal of Soils and Sediments - Electrokinetic (EK) soil remediation is significantly affected by the electrode configurations. Therefore, this study was conducted to compare the performance of... 相似文献
925.
de Sá Silvia Ferreira dos Santos Luísa C. Aragão da Conceição Léo D. H. C. Schwartzhaupt Braga Marcelo Fideles Laviola Bruno Galvêas Cardoso Alexandre Nunes Sayd Ricardo Meneses Junqueira Nilton T. Vilela 《Genetic Resources and Crop Evolution》2021,68(8):3193-3204
Genetic Resources and Crop Evolution - Macauba [Acrocomia aculeata (Jacq.) Lodd. ex Mart.], a palm tree native to Brazil, has a high potential as an alternative source for vegetal oil production.... 相似文献
926.
de Pádua Joelma Aparecida Rabelo Rocha Lucas Fernandes Brandão Murilo Malveira de Almeida Vieira Fábio de Carvalho Dulcinéia 《Genetic Resources and Crop Evolution》2021,68(6):2483-2494
Genetic Resources and Crop Evolution - Eremanthus erythropappus (DC.) MacLeish, commonly known as candeia, is a threatened tree species that occurs in Seasonal Semideciduous Forests in Brazil. The... 相似文献
927.
为了及时了解国际小麦育种的发展动态,介绍了国外在小麦秆锈病新小种Ug99抗性方面的研究进展,主要包括成立国际锈病研究协作网,负责全球范围的小麦锈病研究;基本明确了Ug99的可能传播路线;在肯尼亚对17个国家和组织的4157份小麦品种进行了抗性鉴定,337份表现抗病,为抗病育种提供了重要亲本;明确了现有抗性基因的利用价值,建议利用Sr2、Sr24、Sr26、Sr36、SrTmp和来自1A/1R易位的未知抗性基因,采用持久抗性与主效基因相结舍的策略,通过分子标记辅助选择提高品种选育效率。最后提出了国内技术储备的主要内容。 相似文献
928.
Characterization of intracellular and extracellular saxitoxin levels in both field and cultured Alexandrium spp. samples from Sequim Bay, Washington 下载免费PDF全文
Lefebvre KA Bill BD Erickson A Baugh KA O'Rourke L Costa PR Nance S Trainer VL 《Marine drugs》2008,6(2):103-116
Traditionally, harmful algal bloom studies have primarily focused on quantifying toxin levels contained within the phytoplankton cells of interest. In the case of paralytic shellfish poisoning toxins (PSTs), intracellular toxin levels and the effects of dietary consumption of toxic cells by planktivores have been well documented. However, little information is available regarding the levels of extracellular PSTs that may leak or be released into seawater from toxic cells during blooms. In order to fully evaluate the risks of harmful algal bloom toxins in the marine food web, it is necessary to understand all potential routes of exposure. In the present study, extracellular and intracellular PST levels were measured in field seawater samples (collected weekly from June to October 2004–2007) and in Alexandrium spp. culture samples isolated from Sequim Bay, Washington. Measurable levels of intra- and extra-cellular toxins were detected in both field and culture samples via receptor binding assay (RBA) and an enzyme-linked immunosorbent assay (ELISA). Characterization of the PST toxin profile in the Sequim Bay isolates by pre-column oxidation and HPLC-fluorescence detection revealed that gonyautoxin 1 and 4 made up 65 ± 9.7 % of the total PSTs present. Collectively, these data confirm that extracellular PSTs are present during blooms of Alexandrium spp. in the Sequim Bay region. 相似文献
929.
One of the great advantages of the fully sequenced rice genome is to serve as a reference for other cereal genomes in particular for identifying genes linked to unique traits. A trait of great interest is reduced lignocellulose in the stem of related species in favor of fermentable sugars as a source of biofuels. While sugarcane is one of the most efficient biofuel crops, little is known about the underlying gene repertoire involved in it. Here, we take advantage of the natural variation of sweet and grain sorghum to uncover genes that are conserved in rice, sorghum, and sugarcane but differently expressed in sweet versus grain sorghum by using a microarray platform and the syntenous alignment of rice and sorghum genomic regions containing these genes. Indeed, enzymes involved in carbohydrate accumulation and those that reduce lignocellulose can be identified. 相似文献
930.
G. D. Almeida D. Pratissoli J. C. Zanuncio V. B. Vicentini A. M. Holtz J. E. Serrão 《Phytoparasitica》2009,37(3):225-230
Frankliniella schultzei Trybon (Thysanoptera: Thripidae) is an important pest of tomato plants. The need for more healthful foods is stimulating
the development of techniques to increase plant resistance to phytophagous insects. The objective of this research was to
evaluate the effect of calcium silicate and an organic mineral fertilizer, alone or in combination, on the resistance of tomato
plants to F. schultzei. The treatments consisted of: control (T1), calcium silicate (T2), organic mineral fertilizer (T3), and calcium silicate
with organic mineral fertilizer (T4). The mortality of nymphs of this thrips and the number of lesions on tomato leaves were
evaluated after three, six, nine and 12 applications of these products. The number of F. schultzei individuals and of lesions on tomato leaves was lower in treatments T2 and T4 than in T1 and T3, showing a possible increase
in tomato resistance to this pest. The increase in the number of applications of calcium silicate and the organic mineral
fertilizer increased the mortality of nymphs and reduced the damage by this insect on tomato leaves, mainly after nine applications. 相似文献