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991.
Florence Z. Tarun-Acay 《Small-Scale Forestry》2005,4(1):101-116
An assessment was made of the attributes of People’s Organisations (POs) and of the institutional viability of Community-Based
Forest Management (CBFM) programs in three project sites in the Philippines. In CBFM, the capacity of People’s Organisations,
as de facto managers of forest resources, is being developed by non-government organisations under the guidance of local government units
(LGUs) and the Department of Environment and Natural Resources (DENR). A survey was conducted of community members (case informants)
and members of the various agencies (key informants) to ascertain the characteristics of successful POs and the relationship
between these characteristics and the viability of CBFM. Although commendable contributions have been made to the forest management
capability of POs, their standard of living and environmental conditions, there are also many instances in which institutional
conflict among stakeholders is apparent. The great challenge for the various stakeholders is to orchestrate their differing
interests so as to address successfully the critical issues of the low socioeconomic status of PO members, corruption, lack
of transparency and accountability of the organisations involved, loss of interest of PO members in project activities, lack
of technical assistance, loss of credibility of the DENR, and lack of equitable benefit sharing. 相似文献
992.
Rashmi Kumari Hirokazu Ito Masahiro Takatani Miho Uchiyama Tadashi Okamoto 《Journal of Wood Science》2007,53(6):470-480
Although wood/cellulose-plastic composites (WPC) of low wood/cellulose content have been more accepted worldwide and are promoted
as low-maintenance, high-durability building products, composites containing high wood/cellulose content are not yet developed
on an industrial scale. In this study, flow properties, mechanical properties, and water absorption properties of the compounds
of cellulose microfiber/polypropylene (PP) and maleic anhydride-grafted polypropylene (MAPP) were investigated to understand
effects of the high cellulose content and the dimensions of the cellulose microfiber. The molding processes studied included
compression, injection, and extrusion. It was found that fluidity is not only dependent on resin content but also on the dimension
of the filler; fluidity of the compound declined with increased fiber length with the same resin content. Dispersion of the
composite was monitored by charge-coupled device (CCD) microscope. Increasing the plastic content in the cellulose-plastic
formulation improved the strength of mold in addition to the bond development between resin and filler, and the tangle of
fibers. The processing mode affected the physicomechanical properties of the cellulosic plastic. Compression-molded samples
exhibited the lowest modulus of rupture (MOR) and modulus of elasticity (MOE) and the highest water absorption, while samples
that were injection-molded exhibited the highest MOR (70 MPa) and MOE (7 GPa) and low water absorption (2%). 相似文献
993.
Large-scale deployment of a rice 6 K SNP array for genetics and breeding applications 总被引:1,自引:0,他引:1
Michael J. Thomson Namrata Singh Maria S. Dwiyanti Diane R. Wang Mark H. Wright Francisco Agosto Perez Genevieve DeClerck Joong Hyoun Chin Geraldine A. Malitic-Layaoen Venice Margarette Juanillas Christine J. Dilla-Ermita Ramil Mauleon Tobias Kretzschmar Susan R. McCouch 《Rice》2017,10(1):40
Background
Fixed arrays of single nucleotide polymorphism (SNP) markers have advantages over reduced representation sequencing in their ease of data analysis, consistently higher call rates, and rapid turnaround times. A 6 K SNP array represents a cost-benefit “sweet spot” for routine genetics and breeding applications in rice. Selection of informative SNPs across species and subpopulations during chip design is essential to obtain useful polymorphism rates for target germplasm groups. This paper summarizes results from large-scale deployment of an Illumina 6 K SNP array for rice.Results
Design of the Illumina Infinium 6 K SNP chip for rice, referred to as the Cornell_6K_Array_Infinium_Rice (C6AIR), includes 4429 SNPs from re-sequencing data and 1571 SNP markers from previous BeadXpress 384-SNP sets, selected based on polymorphism rate and allele frequency within and between target germplasm groups. Of the 6000 attempted bead types, 5274 passed Illumina’s production quality control. The C6AIR was widely deployed at the International Rice Research Institute (IRRI) for genetic diversity analysis, QTL mapping, and tracking introgressions and was intensively used at Cornell University for QTL analysis and developing libraries of interspecific chromosome segment substitution lines (CSSLs) between O. sativa and diverse accessions of O. rufipogon or O. meridionalis. Collectively, the array was used to genotype over 40,000 rice samples. A set of 4606 SNP markers was used to provide high quality data for O. sativa germplasm, while a slightly expanded set of 4940 SNPs was used for O. sativa X O. rufipogon populations. Biparental polymorphism rates were generally between 1900 and 2500 well-distributed SNP markers for indica x japonica or interspecific populations and between 1300 and 1500 markers for crosses within indica, while polymorphism rates were lower for pairwise crosses within U.S. tropical japonica germplasm. Recently, a second-generation array containing ~7000 SNP markers, referred to as the C7AIR, was designed by removing poor-performing SNPs from the C6AIR and adding markers selected to increase the utility of the array for elite tropical japonica material.Conclusions
The C6AIR has been successfully used to generate rapid and high-quality genotype data for diverse genetics and breeding applications in rice, and provides the basis for an optimized design in the C7AIR.994.
Sabhavat Bhaskar Naik Dhanasekar Divya Nihar Sahu Raman Meenakshi Sundaram Preetinder Singh Sarao Kuldeep Singh Vattikuti Jhansi Lakshmi Jagadish Sanmallappa Bentur 《Euphytica》2018,214(3):53
The rice brown planthopper (BPH) Nilaparvata lugens (Stål) is one of the major pests of rice across Asia. Host-plant resistance is the most ecologically acceptable means to manage this pest. A rice breeding line RP2068-18-3-5 (RP2068) derived from the land race Velluthacheera is reported to be resistant to BPH populations across India. We identified a new R gene [Bph33(t)] in this line using advanced generation RILs derived from TN1 × RP2068 cross through phenotyping at two locations and linkage analysis with 99 polymorphic SSR markers. QTL analysis through IciMapping identified at least two major QTL on chromosome 1 influencing seedling damage score in seed box screening, honey dew excretion by adults and nymphal survival. Since no BPH R gene has been reported on chromosome 1, we designate this locus as a new gene Bph33(t) which accounted for over 20% of phenotypic variance. Scanning the region for candidate gene suggested two likely candidates a leucine rich repeat (LRR) gene and a heat shock protein (HSP) coding gene. Expression profiling of the two genes in the two contrasting parents and RILs showed induction of the HSP gene (LOC_Os01g42190.1) at 6 h after infestation while LRR gene did not show such induction. It is likely that the HSP represented Bph33(t). 相似文献
995.
996.
The mud crab Scylla paramamosain is a widely farmed commercial species in southeast coastal areas of China. The crabs are placed in water-free containers for transportation to inland markets, thus are exposed to dry conditions for more than 72 h after capture and may suffer from air exposure stress, triggering cell apoptosis leading to death. To evaluate whether an inhibitor of apoptosis protein (IAP) is involved in apoptosis resistance against air exposure stress in crustaceans, SpIAP was cloned and investigated for the first time. The full length of SpIAP was 3351 bp, encoding a polypeptide of 662 amino acids. The predicted SpIAP protein contained three baculoviral IAP repeat domains and one really interesting new gene (RING) finger domain. Protein basic local alignment search tool and phylogenetic analysis results showed that SpIAP was clustered together with other crustaceans IAPs. SpIAP was detected in all the examined tissues and predominantly expressed in the hepatopancreas. When crabs were challenged with air exposure for 12 h, the expression level of SpIAP in the hepatopancreas was significantly increased in the experimental group compared with the control group. A RNA interference assay and flow cytometry analysis showed that when SpIAP was silenced, the cell apoptotic rate significantly increased after 24 h air exposure. These results suggested that SpIAP was involved in an anti-apoptosis response induced by air exposure in S. paramamosain. 相似文献
997.
Inge M. Hanssen Anneleen Paeleman Lieve Wittemans Kris Goen Bart Lievens Claude Bragard Alfons C. R. C. Vanachter Bart P. H. J. Thomma 《European journal of plant pathology / European Foundation for Plant Pathology》2008,121(2):131-146
Over a period of a few years, Pepino mosaic virus (PepMV) has become one of the most important viral diseases in tomato production worldwide. Infection by PepMV can cause
a broad range of symptoms on tomato plants, often leading to significant financial losses. At present, five PepMV genotypes
(EU, LP, CH2, US1 and US2) have been described, three of which (EU, LP and US2) have been reported in Europe. Thus far, no
correlation has been found between different PepMV genotypes and the symptoms expressed in infected plants. In this paper,
the genetic diversity of the PepMV population in Belgian greenhouses is studied and related to symptom development in tomato
crops. A novel assay based on restriction fragment length polymorphism (RFLP) was developed to discriminate between the different
PepMV genotypes. Both RFLP and sequence analysis revealed the occurrence of two genotypes, the EU genotype and the CH2 genotype,
within tomato production in Belgium. Whereas no differences were observed in symptom expression between plants infected by
one of the two genotypes, co-infection with both genotypes resulted in more severe PepMV symptoms. Furthermore, our study
revealed that PepMV recombinants frequently occur in mixed infections under natural conditions. This may possibly result in
the generation of viral variants with increased aggressiveness. 相似文献
998.
Yuuri Hirooka Takao Kobayashi Jun Takeuchi Tsuyoshi Ono Yasunori Ono Keiko T. Natsuaki 《Journal of General Plant Pathology》2007,73(5):330-335
A ring spot disease of Aloe vera was found on leaves of potted seedlings of Aloe vera in Hachijojima and Chichijima Islands, Tokyo. From tissue of ring spot lesions, a fungus producing Fusarium-type conidia was consistently isolated. After 1 month, reddish perithecia of nectriaceous fungus had formed on the colonies
of this isolate on PDA. These nectriaceous and Fusarium fungi were identified as Haematonectria haematococca and Fusarium sp., respectively. From a single ascospore isolation, the former was confirmed to be the teleomorph of the Fusarium sp. Typical ring spot lesions were reproduced by artificial inoculations using single ascospore and single conidium isolates.
Inoculations of five species of genus Aloe revealed that they were highly susceptible except for A. arborescens. This is the first report of a disease on Aloe caused by H. haematococca (anamorph: Fusarium sp.) in Japan, and it was named aloe ring spot. 相似文献
999.
Atiqur Rahman Barbhuiya Ayyanadar Arunachalam Prabhat Chandra Nath Mohammed Latif Khan Kusum Arunachalam 《Journal of Forest Research》2008,13(1):25-34
Rates of weight loss and nutrient (N and P) release patterns were studied in the leaf litter of the dominant tree species
(Ailanthus grandis, Altingia excelsa, Castanopsis indica, Duabanga sonneriatioides, Dysoxylum binectariferum, Mesua ferrea,
Shorea assamica, Taluma hodgsonii, Terminalia myriocarpa and Vatica lancefolia) of a tropical wet evergreen forest of northeast India. Nitrogen and phosphorus mineralization rate and decay pattern varied
significantly from species to species. In general, the decay pattern, characterized by using a composite polynomial regression
equation, exhibited three distinct phases of decay during litter decomposition—an initial slow decay phase (0.063% weight
loss day−1), followed by a rapid decay phase (0.494% weight loss day−1) and a final slow decay phase (0.136% weight loss day−1). The initial chemical composition of the litter affected decomposition rates and patterns. Species like D. sonneriatoides, D. binectariferum, and T. hodgsonii with higher N and P content, lower carbon and lignin content, and lower C:N ratio and lignin:N ratio exhibited relatively
faster decomposition rates than the other species, for example M. ferrea, C. indica and A. grandis. A slow decay rate was recorded for species such as M. ferrea, C. indica, and A. grandis. The initial N and P content of litter showed significant positive correlations with decay rates. Carbon and lignin content,
lignin:N, and C:N showed significant negative correlations with decay rates. Soil total N and P, and rainfall, soil temperature,
and soil moisture had positive correlations with decay rates. The rapid decomposition rates observed in comparison with other
different forest litter decay rates confirm that tropical wet evergreen forest species are characterized by faster decomposition
rates, indicating a faster rate of organic matter turnover and rapid nutrient cycling. 相似文献
1000.
Umma Tamima 《林业研究》2016,27(4):853-861
The objective was to evaluate the performance of the co-management of Nishorgo Support Project at Chunati Wildlife Sanctuary in Bangladesh. I adopted the Focus Groups Discussion method for opinion survey and applied the SWOTAHP technique for data analysis. Local people did not participate in the decision-making process of forest management and they perceived co-management as a threat to their livelihoods. Moreover, mistrust and misunderstanding among different stakeholders, political and ethical conflicts, lack of property rights of tribal communities, and lack of accountability and transparency were identified as the drawbacks of co-management. 相似文献