Plant species composition and product utility pattern of Garo homegardens in Meghalaya, India

Home garden is a traditional landuse system practiced by many rural households in the tropical region. The composition and management practices within homegardens are largely driven by cultural setup and ecological conditions. The present study characterized the plant species composition, utility patterns and management of  Garo homegardens in Dadenggre block, West Garo Hill district of Meghalaya, India. Fifty households from 5 villages were randomly selected and interviewed using a semi-structured questionnaire. The homegardens size ranged between 0.07 and 1.29ha, harbouring 132 plant species, out of which 74 species were trees, 19 shrubs and 39 herbs. Among the perennials, Areca catechu (areca nut) was the most common contributor to household earnings. When species were grouped into 9 utility classes (timber, medicinal, fruit, fuelwood, fodder, vegetables, ornamental, spice, and others), highest number was for fuelwood, followed by vegetables and fruits. The average household income was Rs. 318/100m2, the highest contribution from the sale of vegetables. Various home garden management activities were conducted, engaging family members and generating employment for others. Animal rearing is common in many households and the application of animal manure and household waste has helped maintain soil fertility of homegardens’ soils. Homegardens are integral to the Garo society, contributing significantly to household needs and activities.

Validation of a laboratory method for evaluating dynamic properties of reconstructed equine racetrack surfaces.

BackgroundRacetrack surface is a risk factor for racehorse injuries and fatalities. Current research indicates that race surface mechanical properties may be influenced by material composition, moisture content, temperature, and maintenance. Race surface mechanical testing in a controlled laboratory setting would allow for objective evaluation of dynamic properties of surface and factors that affect surface behavior.ObjectiveTo develop a method for reconstruction of race surfaces in the laboratory and validate the method by comparison with racetrack measurements of dynamic surface properties.MethodsTrack-testing device (TTD) impact tests were conducted to simulate equine hoof impact on dirt and synthetic race surfaces; tests were performed both in situ (racetrack) and using laboratory reconstructions of harvested surface materials. Clegg Hammer in situ measurements were used to guide surface reconstruction in the laboratory. Dynamic surface properties were compared between in situ and laboratory settings. Relationships between racetrack TTD and Clegg Hammer measurements were analyzed using stepwise multiple linear regression.ResultsMost dynamic surface property setting differences (racetrack-laboratory) were small relative to surface material type differences (dirt-synthetic). Clegg Hammer measurements were more strongly correlated with TTD measurements on the synthetic surface than the dirt surface. On the dirt surface, Clegg Hammer decelerations were negatively correlated with TTD forces.ConclusionsLaboratory reconstruction of racetrack surfaces guided by Clegg Hammer measurements yielded TTD impact measurements similar to in situ values. The negative correlation between TTD and Clegg Hammer measurements confirms the importance of instrument mass when drawing conclusions from testing results. Lighter impact devices may be less appropriate for assessing dynamic surface properties compared to testing equipment designed to simulate hoof impact (TTD).Potential relevanceDynamic impact properties of race surfaces can be evaluated in a laboratory setting, allowing for further study of factors affecting surface behavior under controlled conditions

Encapsulated somatic embryos of grape (Vitis vinifera L.): An efficient way for storage and propagation of pathogen-free plant material

Cotyledonary-stage somatic embryos (5-7 mm in length) originating from leaf explants of grape (Vitis vinifera L.) cv. Pusa seedless were encapsulated individually in 2 % alginate gel. The encapsulated somatic embryos (ESEs) germinated successfully on 0.7 % agar medium containing B5 macrosalts (half strength), MURASHIGE and SKOOG microsalts (full strength), 3 % sucrose and 2.9 μM gibberellic acid. The percentage of germination of ESEs was higher than that of nonencapsulated somatic embryos (NSEs) of the same size on the same medium. The percent germination of ESEs increased (69.2 ±2.8) on medium supplemented with quarter strength B5 macrosalts. Of the germinating ESEs, 36 % developed into plantlets. Abscisic acid at 0.004 and 0.02 μM had no significant influence on the frequency of germination and plantlet development, however resulted in a 4-week delay in germination. Transferring the embryos onto the full-strength B5 medium containing sucrose and ABA (0.04 μM) for 4-6 weeks prior to encapsulation resulted in extended storage of up to 90 d without loss of the germination potential and the capacity to regenerate into plantlets. Normally developed plantlets regenerated from ESEs were successfully adapted to soil.

Effects of Surface Depth and Compaction on Impact Deceleration of Dirt and Synthetic Surface Materials for Equine Racetracks

Abstract is attached

Dual-Band Compact Metamaterial-Inspired Absorber with Wide Incidence Angle and Polarization Insensitivity for GSM and ISM Band Applications

A dual-band metamaterial inspired microwave absorber composed of concentric two crossed double-arrow shaped resonators, ring resonator with four splits at the corners and square ring resonator is presented. The proposed RF absorber has the absorption feature of wide incidence angle. The sub-wavelength unit cell of the proposed absorber is structured on a metal backed epoxy glass (FR-4) substrate. The novel absorber has two distinct absorption peaks of 99.4% and 98.6% at the frequencies of 1.94 GHz and 2.4 GHz, respectively. The designed structure is polarisation-insensitive with wide incidence angle of 60° and high absorption rate of 82% for transverse electric and 98% for transverse magnetic modes. Polarization insensitivity of the proposed design is investigated by the waveguide measurement technique with setting different orientation angles for the unit cells. The measured and simulated results have good agreement making the proposed absorber a potential candidate for energy harvesting applications in GSM and ISM band

Correction: Validation of a Laboratory Method for Evaluating Dynamic Properties of Reconstructed Equine Racetrack Surfaces.

[This corrects the article DOI: 10.1371/journal.pone.0050534.]

Genetic diversity and demographic history of Cajanus spp. illustrated from genome-wide SNPs

Understanding genetic structure of Cajanus spp. is essential for achieving genetic improvement by quantitative trait loci (QTL) mapping or association studies and use of selected markers through genomic assisted breeding and genomic selection. After developing a comprehensive set of 1,616 single nucleotide polymorphism (SNPs) and their conversion into cost effective KASPar assays for pigeonpea (Cajanus cajan), we studied levels of genetic variability both within and between diverse set of Cajanus lines including 56 breeding lines, 21 landraces and 107 accessions from 18 wild species. These results revealed a high frequency of polymorphic SNPs and relatively high level of cross-species transferability. Indeed, 75.8% of successful SNP assays revealed polymorphism, and more than 95% of these assays could be successfully transferred to related wild species. To show regional patterns of variation, we used STRUCTURE and Analysis of Molecular Variance (AMOVA) to partition variance among hierarchical sets of landraces and wild species at either the continental scale or within India. STRUCTURE separated most of the domesticated germplasm from wild ecotypes, and separates Australian and Asian wild species as has been found previously. Among Indian regions and states within regions, we found 36% of the variation between regions, and 64% within landraces or wilds within states. The highest level of polymorphism in wild relatives and landraces was found in Madhya Pradesh and Andhra Pradesh provinces of India representing the centre of origin and domestication of pigeonpea respectively. © 2014 Saxena et al

Wild Sorghums—Their Potential Use in Crop Improvement

Wild relatives of crops, sorghum being no exception, continue to play a key role in the development of high performing cultivars. Among the 22 species comprising this highly variable genus, only one, Sorghum bicolor, is commercially cultivated for food, feed and bioenergy production. The wild sorghums thus offer opportunities for further genetic enhancement of this crop. Profi table utilization of wild species however demands an inter-disciplinary, multi-pronged approach to increase the probability of achieving the desired genetic improvement. To this end, this chapter presents a review of the current knowledge on (1) biosystematic aspects such as botany, taxonomy and classifi cation, (2) domestication and evolution, including centers of diversity, genetic diversity, chromosome homologies and species/ phylogenetic relationships, (3) genetic resources, genepools and conservation perspectives including collections and preservation of germplasm, (4) utilization aspects including the specifi c potential of the wild species in crop improvement with reference to insect and disease resistance, yield, grain quality, ecological adaptation, allopatric resistance, and (5) strategies to maximize utilization of wild germplasm resources including direct hybridization, reproductive barriers and their circumvention, chromosome and physiological manipulation, the gaps between hybridization and utilization and molecular interventions. Recent advancements in biotechnology, in particular, are expected to increase the effi ciency and range of use of these wild sorghum species