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991.
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
992.
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
993.
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
994.
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
995.
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
996.
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
997.
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
998.
éverton Tenório de Souza Daysianne Pereira de Lira Aline Cavalcanti de Queiroz Diogo José Costa da Silva Anansa Bezerra de Aquino Eliane A. Campessato Mella Vitor Prates Lorenzo George Emmanuel C. de Miranda Jo?o Xavier de Araújo-Júnior Maria Célia de Oliveira Chaves José Maria Barbosa-Filho Petr?nio Filgueiras de Athayde-Filho Bárbara Viviana de Oliveira Santos Magna Suzana Alexandre-Moreira 《Marine drugs》2009,7(4):689-704
The antinociceptive and anti-inflammatory activity of caulerpin was investigated. This bisindole alkaloid was isolated from the lipoid extract of Caulerpa racemosa and its structure was identified by spectroscopic methods, including IR and NMR techniques. The pharmacological assays used were the writhing and the hot plate tests, the formalin-induced pain, the capsaicin-induced ear edema and the carrageenan-induced peritonitis. Caulerpin was given orally at a concentration of 100 μmol/kg. In the abdominal constriction test caulerpin showed reduction in the acetic acid-induced nociception at 0.0945 μmol (0.0103–1.0984) and for dypirone it was 0.0426 μmol (0.0092–0.1972). In the hot plate test in vivo the inhibition of nociception by caulerpin (100 μmol/kg, p.o.) was also favorable. This result suggests that this compound exhibits a central activity, without changing the motor activity (seen in the rotarod test). Caulerpin (100 μmol/kg, p.o.) reduced the formalin effects in both phases by 35.4% and 45.6%, respectively. The possible anti-inflammatory activity observed in the second phase in the formalin test of caulerpin (100 μmol/kg, p.o.) was confirmed on the capsaicin-induced ear edema model, where an inhibition of 55.8% was presented. Indeed, it was also observed in the carrageenan-induced peritonitis that caulerpin (100 μmol/kg, p.o.) exhibited anti-inflammatory activity, reducing significantly the number of recruit cells by 48.3%. Pharmacological studies are continuing in order to characterize the mechanism(s) responsible for the antinociceptive and anti-inflammatory actions and also to identify other active principles present in Caulerpa racemosa. 相似文献
999.
Glauco Vieira Miranda Leandro Vagno de Souza João Carlos Cardoso Galvão Lauro José Moreira Guimarães Aurélio Vaz de Melo Izabel Cristina dos Santos 《Euphytica》2008,162(3):431-440
The development of successful advanced lines and cultivars in maize is dependent on parental selection and assignment to defined
heterotic groups. So, the objectives of this study were to evaluate genetic variability and identify heterotic groups among
Brazilian popcorn varieties. Thus, diallel crosses of advanced generations of the popcorn hybrids, IAC 112 and Zélia, and
of three open-pollinated popcorn varieties, RS 20, Branco, and SAM were performed. Ten hybrid combinations, the five parents,
and five check treatments were arranged in a block design with four replicates in two tropical-zone locations (CWb climate).
Both additive and non-additive effects were important for grain yield, plant height, ear height, and husk cover. For popping
expansion, only the additive effects were important. Hybrid combinations between the local variety (Branco) and F2 populations (IAC 112 and Zelia) resulted in the third and fourth highest values for popping expansion. The best grain yields
were obtained with hybrid combinations involving SAM. Cultivars Zélia, IAC 112, and RS 20 increased popping expansion, whereas
cultivar Branco increased grain yield of hybrid combinations. The following conclusions may be drawn: Brazilian popcorn populations
have reduced heterosis and genetic variability to popping expansion in relation commercial cultivars; there is genetic variability
among Brazilian popcorn populations that allows the exploitation of additive and non-additive effects for grain yield; it
is possible to increase grain yield by using local varieties; but it would be difficult to obtain commercial hybrids from
local varieties because they have poor performance for popping expansion. 相似文献
1000.
Martínez-Rocha A Puga R Hernández-Sandoval L Loarca-Piña G Mendoza S 《Plant foods for human nutrition (Dordrecht, Netherlands)》2008,63(1):1-5
Free essential oil methanolic extracts from three different geographical populations of Lippia graveolens in México were screened for antioxidant and antimutagenic properties by the DPPH and Kado microsuspension assay, respectively.
Total phenolic and flavonoid contents as well as HPLC identification and quantification of naringenin and rosmarinic acid
were also carried out. In addition, a taxonomical phenetic analysis was performed. The L. graveolens extracts showed varying content of phenols and flavonoids. Significant concentration of rosmarinic acid was found for the
first time in the species. All the extracts were capable of scavenging DPPH radicals in a concentration dependent fashion;
the IC50 values correlate with the phenolic content. None of the extracts was toxic to TA100 and TA98 strains at the concentrations
tested; moreover, the extracts at a concentration equivalent to 200 μg of gallic acid inhibited a 39 and 30% the mutagenicity
induced by 4-nitro-o-phenylenediamine and sodium azide, respectively. The results suggest that the Mexican oregano is a source of polar bioactive
ingredients for the food industry. 相似文献