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71.
Meeting the challenges of global rice production 总被引:2,自引:0,他引:2
Rice is the second most widely grown cereal crop and the staple food for more than half the world's population. More than
3 billion people consume more than 100 kg of rice per year. Rice is cultivated on 155.5 million ha with an average growth
rate of 0.39% a year, in the last 30 years. In the near future, the possibility for expanding areas under rice-based systems
will remain very limited because of the scarcity of global water resources for agriculture, the expansion of urban and industrial
sectors in Asia where land is already limited and the high costs of developing new lands that are suited for rice production
in Sub-Saharan Africa and Latin America. The average growth rate of rice yield was 3.68% per year in the early 1980s, but
it has decreased to 0.74% per year in the late 1990s. Several factors may contribute to the decline of the area under cultivation
and in yield growth. The most important of these factors are: limited returns as we approach the yield potential of the high
yielding varieties, declining productivity in intensive rice production systems, pressures from abiotic and biotic stresses,
low returns in developing countries, increasing production costs in industrialized countries, and increasing public concern
for the protection of environmental resources. One of the most effective means of addressing the issues in rice cultivation
and raising the average yields at the farm level is through research and subsequent dissemination of the resulting data. Rice
science has made considerable progress. In the area of rice varietal improvement, recent advances in hybrid rice and the new
rice for Africa (NERICA) are just two examples of the successful contributions of science to the development of rice. Research
could also help reduce the gap between the potential yield obtained on experimental stations and the actual yield obtained
in the fields. This could be possible by developing and promoting rice integrated crop management (RICM) systems for improving
productivity and reducing the production cost per unit of output. The need for a sustainable increase in rice production affects
everyone. The International Year of Rice provide us with a chance to improve food security, alleviate poverty and preserve
the environment for the billions of people for whom Rice is Life.
Nguu Van Nguyen About the Author. Nguu Van Nguyen earned his PhD in Agronomy in 1976 from the University of the Philippines at Los Banos (UPLB). He has been
serving for 2 years as Post-Doctoral Fellow, at the International Rice Research Institute and for other two as Assistant Professor
at UPLB University. He has been working from 1980 to 1993 as agronomist at IITA (International Institute of Tropical Agriculture)
and at Philippine Rice Research Institute. In 1991, he began his professional career at FAO, initially as rice agronomist,
in West Africa, then as agricultural officer at Crop and Grassland Service. Since 2004 he is serving as Executive Secretary,
International Rice Commission.
Aldo Ferrero About the Author. Aldo Ferrero is at present Professor of “Weed Science”, “Agronomy” and “Crop Science” and head of the “Department of Agronomy, Forest and Land Management, University of Turin (Italy). He is coordinator of the rice FAO network “Medrice”, for Europe, Mediterranean, and Middle East countries. He possesses a wide experience in the field of the weed eco-biology and weed control in rice systems. He has been co-ordinator of European research projects funded by the European Union. He currently co-ordinates the project “EU-India Rice districts network promotion through agro-economical, cross cultural, and technical actions” (RICE-NET) aimed at studying agro-economical, cultural, and historical traits of the rice cultivation in the European and Indian rice districts, in order to improve socio-economical relationships between the two geographical areas. He is referee and member of the editorial board of several international journals.
相似文献
Aldo Ferrero About the Author. Aldo Ferrero is at present Professor of “Weed Science”, “Agronomy” and “Crop Science” and head of the “Department of Agronomy, Forest and Land Management, University of Turin (Italy). He is coordinator of the rice FAO network “Medrice”, for Europe, Mediterranean, and Middle East countries. He possesses a wide experience in the field of the weed eco-biology and weed control in rice systems. He has been co-ordinator of European research projects funded by the European Union. He currently co-ordinates the project “EU-India Rice districts network promotion through agro-economical, cross cultural, and technical actions” (RICE-NET) aimed at studying agro-economical, cultural, and historical traits of the rice cultivation in the European and Indian rice districts, in order to improve socio-economical relationships between the two geographical areas. He is referee and member of the editorial board of several international journals.
相似文献
72.
73.
Saponins containing a free carboxylic group in the molecule give the corresponding esters as artifacts when stored for a long time in alcoholic solutions. Two saponins from Medicago sativa L., chosen on the basis of their different positions of the carboxylic group in the molecule, were refluxed with methanol and ethanol under neutral conditions. 3,28-di-O-glu medicagenic acid possesses a carboxylic group on the triterpenic moiety, whereas soyasaponin I, a glycoside of soyasapogenol B, has a glucuronic acid unit as the first sugar linked to the triterpene structure. Artifacts were quantified by HPLC. The peaks identified as the corresponding esters were examined during boiling from 1 h to 5 days. Quantitative results indicated that the carboxylic group on the sugar moiety, as for soyasaponin I, is more reactive than that on the triterpenic structure, as for 3,28-di-O-glu medicagenic acid. Saponins having the free carboxylic groups create enough acidity in their alcoholic solutions to catalyze the formation of the corresponding esters. 相似文献
74.
Brandolini V Tedeschi P Cereti E Maietti A Barile D Coïsson JD Mazzotta D Arlorio M Martelli A 《Journal of agricultural and food chemistry》2005,53(3):678-683
Chemotype analyses and random amplified polymorphic DNA (RAPD) genomic analyses have been applied to the characterization of Allium sativum variety from Voghiera (Ferrara, Italy), a typical Italian product actually demanding the Protected Designation of Origin (PDO). The garlic from Voghiera is characterized by peculiar morphological and composition characteristics. The proximate composition and atomic absorbance spectrometry elemental pattern of this garlic suggested as the chemical composition did not depend on the intrinsic pedologic soil features only, but it was probably connected to some peculiar genetic characters. Amplification of genomic DNA using random primers highlighted a good clustering differentiating of Voghiera Allium sativum from five commercial reference samples used in this study (Piacentino, Serena, France, China, and Adriano varieties), confirming the existence of intervarietal genetic difference. The intravarietal polymorphisms of Voghiera samples were low. 相似文献
75.
CLIP identifies Nova-regulated RNA networks in the brain 总被引:1,自引:0,他引:1
76.
Development and validation of an ultrasensitive chemiluminescent enzyme immunoassay for aflatoxin M1 in milk 总被引:1,自引:0,他引:1
Magliulo M Mirasoli M Simoni P Lelli R Portanti O Roda A 《Journal of agricultural and food chemistry》2005,53(9):3300-3305
A fast and ultrasensitive chemiluminescent enzyme immunoassay for aflatoxin M(1) in milk samples has been developed and validated. The method is an indirect competitive type format involving the immobilization of an aflatoxin M(1)-bovine serum albumin conjugate on 384 well black polystyrene microtiter plates and the use of a secondary antibody labeled with horseradish peroxidase detected with a luminol-based substrate. Aflatoxin M(1) standard solutions were prepared in milk-based buffer, and milk samples were analyzed without any cleanup procedure. The limit of quantification was 1 ppt, the coefficient of variation was below 9% for both intra- and interassay precision, and the recovery ranged from 96 to 122%. The method is specific, and other aflatoxins do not significantly cross-react with the antibody. Twenty-four milk samples were analyzed, and a good correlation was observed (y = 0.98x + 1.71, r(2) = 0.98, n = 24) when the data were compared with a reference high-performance liquid chromatography method with a fluorescent detector. The developed method is suitable for an accurate, sensitive, and high-throughput screening of aflatoxin M(1) in milk samples with a reduction of costs and increased detectability, as compared with previously developed immunoassays. 相似文献
77.
Tava A Mella M Avato P Argentieri MP Bialy Z Jurzysta M 《Journal of agricultural and food chemistry》2005,53(26):9954-9965
Eighteen triterpene saponins (1-18) from Medicago arborea leaves have been isolated and their structures elucidated by spectroscopic, spectrometric (1D and 2D NMR, FAB-MS, ESI-MS/MS), and chemical methods. They have been identified as glycosides of medicagenic, zanhic, and 2beta-hydroxyoleanolic acids, soyasapogenol B, bayogenin, and 2beta,3beta-dihydroxyolean-12-en-23-al-28-oic acid. Twelve of them, identified as 3-O-beta-D-glucopyranosyl-28-O-[alpha-L-arabinopyranosyl(1-->3)-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranoside] zanhic acid (3), 3-O-beta-D-glucopyranosyl-28-O-[beta-D-xylopyranosyl(1-->4)-[alpha-L-arabinopyranosyl-(1-->3)]-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranoside] zanhic acid (4), 3-O-[alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranosyl(1-->2)-beta-D-glucopyranosyl]-2beta-hydroxyoleanolic acid (5), 3-O-beta-D-glucuronopyranosyl-28-O-[alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranoside]medicagenic acid (6), 3-O-beta-D-glucuronopyranosyl-28-O-[beta-D-xylopyranosyl(1-->4)-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranoside]bayogenin (9), 3-O-beta-D-glucuronopyranosyl-28-O-[beta-D-xylopyranosyl(1-->4)-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranoside]-2beta,3beta-dihydroxyolean-12-en-23-al-28-oic acid (10), 3-O-beta-D-glucuronopyranosyl-28-O-[beta-D-xylopyranosyl(1-->4)-[beta-D-apiofuranosyl(1-->3)]-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranoside]zanhic acid (12), 3-O-beta-D-glucuronopyranosyl-28-O-[beta-D-xylopyranosyl(1-->4)-[alpha-L-arabinopyranoside(1-->3)]-alpha-L-rhamnopyrano-syl(1-->2)-alpha-L-arabinopyranoside]zanhic acid (13), 3-O-beta-D-glucuronopyranosyl-28-O-[beta-D-xylopyrano-syl(1-->4)-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranoside]zanhic acid (14), 3-O-[alpha-L-arabinopyranosyl-(1-->2)-beta-D-glucopyranosyl(1-->2)-beta-D-glucopyranosyl]-28-O-[beta-D-xylopyranosyl(1-->4)-[beta-D-apiofurano-syl(1-->3)]-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranoside]zanhic acid (16), 3-O-[beta-D-glucopyrano-syl(1-->2)-beta-D-glucopyranosyl]-28-O-[beta-D-xylopyranosyl(1-->4)-[alpha-L-arabinopyranosyl(1-->3)]-alpha-L-rhamno-pyranosyl (1-->2)-alpha-L-arabinopyranoside]zanhic acid (17), and 3-O-beta-D-glucuronopyranosyl-28-O-[beta-D-xylopyranosyl(1-->4)-[beta-D-apiofuranosyl(1-->3)]-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyrano-side]medicagenic acid (18), are reported as new natural compounds. The presence of the aldehydic group on the sapogenin moiety of saponin 10 is discussed in the framework of a possible elucidation of the biosynthesis of these metabolites. 相似文献
78.
Margarida Costa Mónica Garcia Jo?o Costa-Rodrigues Maria Sofia Costa Maria Jo?o Ribeiro Maria Helena Fernandes Piedade Barros Aldo Barreiro Vitor Vasconcelos Rosário Martins 《Marine drugs》2014,12(1):98-114
The oceans remain a major source of natural compounds with potential in pharmacology. In particular, during the last few decades, marine cyanobacteria have been in focus as producers of interesting bioactive compounds, especially for the treatment of cancer. In this study, the anticancer potential of extracts from twenty eight marine cyanobacteria strains, belonging to the underexplored picoplanktonic genera, Cyanobium, Synechocystis and Synechococcus, and the filamentous genera, Nodosilinea, Leptolyngbya, Pseudanabaena and Romeria, were assessed in eight human tumor cell lines. First, a crude extract was obtained by dichloromethane:methanol extraction, and from it, three fractions were separated in a Si column chromatography. The crude extract and fractions were tested in eight human cancer cell lines for cell viability/toxicity, accessed with the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and lactic dehydrogenase release (LDH) assays. Eight point nine percent of the strains revealed strong cytotoxicity; 17.8% showed moderate cytotoxicity, and 14.3% assays showed low toxicity. The results obtained revealed that the studied genera of marine cyanobacteria are a promising source of novel compounds with potential anticancer activity and highlight the interest in also exploring the smaller filamentous and picoplanktonic genera of cyanobacteria. 相似文献
79.
Relationship between grain yield and grain nitrogen concentration in winter triticale 总被引:1,自引:0,他引:1
Summary Ten hexaploid winter triticale lines were grown for two cropping periods at three locations in western Switzerland. Averaged across the six environments, the differences between lines were statistically significant (P=0.05) for grain yield, above-ground biomass, N uptake, grain N yield, nitrogen harvest index, grain N concentration and straw N concentration. There were significant line x environment interactions for all traits. Grain yield and grain N concentration were inversely related (r=–0.74**). Diagrams in which grain yields were plotted against grain N concentration were used to identify lines with a consistently unusual combination of grain yield and grain N concentration. Despite comparable grain yields, Line 3 had a high grain N concentration, while that of Line 7 was low. Line 3 was superior to Line 7 in both N uptake and N harvest index. Averaged across environments and lines, the N harvest index was 0.73 which corresponds to N harvest indices reported for bread wheat in the same region. We considered the feasibility of developing triticale lines which would outperform the best recent ones in N uptake and partitioning. However, we doubted that this would bring about a marked increase in grain N concentration, because, in the long run, the expected genetic progress in grain yield will lead to a dilution of grain protein by grain carbohydrate increments.Abbreviations GNC
grain N concentration
- GNY
grain N yield
- GY
grain yield
- HI
above-ground dry matter harvest index
- NHI
nitrogen harvest index
- SNC
straw N concentration
- TB
total above-ground biomass
- TPN
total plant N 相似文献
80.
Aldo Pavari 《European Journal of Forest Research》1960,79(11-12):333-345