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51.
Shortage of fodder is a major constraint to livestock production in Nepal. The genetic variation in canopy biomass production of Bauhinia purpurea L, a very important fodder species in Nepal, was estimated in a Breeding Seed Orchard in order to examine the potential of simple, low input breeding. Substantial genetic variation could be observed suggesting that low input breeding based on simple phenotypic selection can provide biomass gain in the order of 2–5% per year. Very high correlation was observed between stem diameter (cross section area) and total biomass, making farmer based selection relevant. Jointly, these results suggest that low input domestication is a promising option for improving fodder production in Nepal and thereby help to improve rural livelihood and development. A multiple population approach is recommended.  相似文献   
52.
The paper examines the two forest certification schemes in Brazil, the Brazilian Program of Forest Certification (Cerflor) and the Forest Stewardship Council (FSC), from the private sector perspective. The main focus is to test the relevance of three mechanisms—market, learning, and signaling—suggested by Overdevest and Rickenbach (2006), to explain forest certification adoption by Brazilian companies. Furthermore, companies' familiarity with certification systems, external influences on pursuing forest certification, and companies' intention to recertify their forests are investigated. An exploratory factor analysis (EFA) suggests that signaling and learning mechanisms lead to better and more transparent forest management, explaining the movement towards certification, but market incentives do not play an important role in the adoption of forest certification. An importance and performance analysis (IPA) demonstrates that companies do not see any return in terms of a better price for certified products; however, certificate holders indicated overall high satisfaction with market access. Interestingly, a high performance was found for non-economic benefits such as public confidence, improvement of forest management and practices, improvement of management systems and performance, self-discovery of non-conformance, and better public, landowner, and supplier communication. International consumers and shareholders were considered the most important groups influencing companies to seek certification and FSC was reported to be the most familiar scheme. Generally, companies were pleased with certification and indicated their intention to recertify.  相似文献   
53.
The date palm (Phoenix dactylifera L.) is dioecious with male flowers deficient in functional gynoecium and female flowers deficient in functional androecium borne on separate palms. The presence of male and female flowers on the same plant, a phenomenon known as monoecy, is unusual in male date palms.

This study reports for the first time on hermaphrodite (bisexual) flowers borne by two female date palms, ‘Alligue’, that were found growing in an open field in Degache, southern Tunisia. The observations on these two female palms were compared with hermaphrodite male date palms growing in the same location. Hermaphrodite female date palm inflorescence branches bear female flowers predominantly near their base, in contrast to the hermaphrodite flowers that are found primarily toward their upper part. The position of the hermaphrodite flowers in hermaphrodite male date palms is reversed: inflorescence branches bear male flowers toward the upper part while the hermaphrodite flowers are found at the base. Histological examination of female hermaphrodite flowers revealed that they had three carpels and 1–6 stamens. Hermaphrodite flowers on male plants were usually also composed of three carpels of variable size, and six stamens. Hermaphrodite flowers on both female and male palm trees turn generally into parthenocarpic fruits. The present data support the theory that dioecious plants are derived from a common hermaphrodite ancestor. Floral hermaphroditism in date palm should be investigated in relation to the in planta self-fertilization process to identify sex markers and genes that control sex organ development.  相似文献   

54.
Agroforestry Systems - This article presents a methodology for the valuation of agroforestry with respect to fuelwood supply for cooking and its opportunity cost. The share of fuelwood consumption...  相似文献   
55.

Effects of zinc oxide nanoparticles (ZnO NPs) and Rhizobium leguminosarum alone and in combination were observed on the disease complex of pea caused by Meloidogyne incognita and Pseudomonas syringae pv. pisi. Plants inoculated with M. incognita and P. syringae pv. pisi, alone or in combination, showed a significant reduction in plant growth, chlorophyll and carotenoid content compared to uninoculated controls. Use of ZnO NPs (0.10?ml?1) as seed priming resulted in a greater increase in plant growth than 0.10?ml?1 foliar spray. Plants inoculated with R. leguminosarum had better plant growth, chlorophyll and carotenoid content than plants without R. leguminosarum. Greater plant growth, chlorophyll and carotenoid content were observed when NPs primed seeds were grown with R. leguminosarum than the use of NPs foliar spray plus R. leguminosarum. Plants inoculated with R. leguminosarum showed higher root nodulation while only few nodules were observed in plants without R. leguminosarum. Both tested pathogens had adverse effect on nodulation, while use of ZnO NPs with R. leguminosarum also reduced nodulation. ZnO NPs and R. leguminosarum reduced blight disease indices, galling and nematode population. Use of ZnO NPs primed seeds with R. leguminosarum resulted in the highest reduction in disease indices, galling and nematode population. The segregation of various treatments in the biplot of principal component analysis demonstrates a suppressive role of ZnO NPs on blight disease complex of pea.

  相似文献   
56.
Genetic Resources and Crop Evolution - ‘Garlic’ (Allium sativum L.) is the second most important cultivated Allium known throughout the world. It is known for its versatile use as a...  相似文献   
57.
An insight into the epidemiology of dolphin morbillivirus worldwide   总被引:2,自引:0,他引:2  
Serum samples from 288 cetaceans representing 25 species and originating from 11 different countries were collected between 1995 and 1999 and examined for the presence of dolphin morbillivirus (DMV)-specific antibodies by an indirect ELISA (iELISA) (N = 267) or a plaque reduction assay (N = 21). A total of 35 odontocetes were seropositive: three harbour porpoises (Phocoena phocoena) and a common dolphin (Delphinus delphis) from the Northeastern (NE) Atlantic, a bottlenose dolphin (Tursiops truncatus) from Kent (England), three striped dolphins (Stenella coeruleoalba), two Risso's dolphins (Grampus griseus) and a bottlenose dolphin from the Mediterranean Sea, one common dolphin from the Southwest (SW) Indian Ocean, three Fraser's dolphins (Lagenodelphis hosei) from the SW Atlantic, 18 long-finned pilot whales (Globicephala melas) and a bottlenose dolphin from the SW Pacific as well as a captive bottlenose dolphin (Tursiops aduncus) originally from Taiwan. The presence of morbillivirus antibodies in 17 of these animals was further examined in other iELISAs and virus neutralization tests. Our results indicate that DMV infects cetaceans worldwide. This is the first report of DMV-seropositive animals from the SW Indian, SW Atlantic and West Pacific Oceans. Prevalence of DMV-seropositives was 85.7% in 21 pilot whales from the SW Pacific and both sexually mature and immature individuals were infected. This indicates that DMV is endemic in these animals. The same situation may occur among Fraser's dolphins from the SW Atlantic. The prevalence of DMV-seropositives was 5.26% and 5.36% in 19 common dolphins and 56 harbour porpoise from the NE Atlantic, respectively, and 18.75% in 16 striped dolphins from the Mediterranean. Prevalence varied significantly with sexual maturity in harbour porpoises and striped dolphins; all DMV-seropositives being mature animals. The prevalence of seropositive harbour porpoise and striped dolphins appeared to have decreased since previous studies. These data suggest that DMV is not endemic within these populations, that they are losing their humoral immunity against the virus and that they may be vulnerable to new epidemics.  相似文献   
58.
The paper uses cause mapping and structural analysis to analyse how key consensus-building criteria influence the development of cooperation among and between stakeholders and a government agency. The analyses are based on a comparative study of two Local Citizens Committees (LCCs) in Ontario, Canada. Given–Means–Ends (GME) analysis is used to identify the informal goals of LCCs, including the development of cooperation, and LCCs' influence over consensus-building criteria, and Context, Structure and Performance (CSP) analysis is used to identify the relative influence of key consensus-building criteria on cooperation criteria. The paper concludes with a discussion of the relationship between the structural analysis and content analysis of the same data and four inferences for consensus-building and co-management theories.  相似文献   
59.
The impact of county-level bamboo sector reforms on bamboo contributions to the county economy is examined by using aggregate county data and simple analytical methods. The role of the contributions of bamboo to the different income groups is evaluated on the basis of data, for 1987 and 1997, from 46 households and by using Gini coefficients, relative and absolute inequality weights, and movements of households through different income groups. Fresh bamboo shoot (FBS) production increased from US$0.1 million in 1983 to US$29 million in 1996. Allocation of labor and capital reached near optimal by the end of the first phase of forestland reforms in 1987. Industrial reforms could affect land allocation through price incentives. Market reforms had a much higher impact through price incentives on land allocation. Bamboo contributions have benefited poor as well as rich groups, and these contributions have moved many households from the poorer to the richer classes. Bamboo sector reforms have reduced the inequality in bamboo land and bamboo income but the share of bamboo income in the total income inequality has increased. The local governments should recognize these outcomes and the basic differences in the production of different bamboo products to design future reforms.  相似文献   
60.
The petiole on pigeonpea was removed for easy, precise inoculation of node with Phytophthora drechsleri f. sp. cajani. After node inoculation, 96.0% plants were infected compared with 89.0% after stem-cut inoculation. Among various nodes inoculated on 30-day-old plants, the 5th node had the greatest relative susceptibility (90.0%), followed by the 3rd node (78.0%). This technique was validated on different cultivars (ICP 7119, Bahar, MA 6 and MAL 13), and 586 lines were successfully screened in the field, confirming the rapidity and effectiveness of the technique for resistance screening.  相似文献   
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