Information on the genetic diversity of wild rice species in Sri Lanka is relatively meagre,though it plays a key role in crop improvement programs of cultivated rice(Oryza sativa L.).The present study was carried out...
详细信息
Information on the genetic diversity of wild rice species in Sri Lanka is relatively meagre,though it plays a key role in crop improvement programs of cultivated rice(Oryza sativa L.).The present study was carried out to identify the morphological variation pattern of the wild populations of O.nivara in Sri Lanka.Seven populations(P1 to P7)collected from different agro-ecological regions were characterized in a common garden based on nine morphological traits.The findings revealed a high level of phenotypic variation between populations when compared to within a population.The most variable traits were the flag leaf panicle neck length(FLPNL)and flag leaf angle(FLA),whereas the least variable trait was the flag leaf length(FLL).Box plots clearly illustrated the large differentiation of phenotypic traits in the entire distribution of wild rice populations.The cumulative values of the two principal components,i.e.,FLPNL and FLA,explained 58.7%of the total variance.Populations from similar natural habitats clustered together.The P7 was adapted to intercept more sunlight by increasing flag leaf width(FLW)and FLA to compete with weeds and other shrubs.P2 and P5 were the most closely related populations representing approximately similar ecological conditions of the dry zone.The P3 population from the intermediate zone showed a vigorous plant growth with the highest plant height,culm girth and awn length(P<0.05).Knowledge of such morphological diversity would facilitate designing conservation strategies and basic information for the proper utilization of wild resources in rice genetic improvement.
Conventional, grid-based sampling location tracking approach with GPS or topographic maps is time-consuming and inconvenient. Therefore, this study combined the freely available virtual/digital globe with recent advan...
详细信息
Conventional, grid-based sampling location tracking approach with GPS or topographic maps is time-consuming and inconvenient. Therefore, this study combined the freely available virtual/digital globe with recent advancements of smartphone geo-browsers to develop a new sampling location tracking approach. The sampling frame was developed with pre-uploaded point map formulated in GIS environment by combining land-use map and one-kilometer grid with center coordinates. The sampling location grid was uploaded to smartphone and each point was tracked with Google Map path finder using point ID (coded grid coordinate) when searching each sampling location. The suitability of the new approach was tested for soil sample collection from paddy lands distributed in 0.9 million hectares in Sri Lanka. The sampling locations could be reached conveniently with the help of Google path-finder voice direction guide and optional routes. The efficiency of new approach was found to be remarkably high, i.e., over 99% of the 9000 sampling points, which were spread across Sri Lanka having an area of 65,610 km2. All sampling points in the country could be covered with twelve member field investigation crew who were guided through smartphones uploaded with sampling point grid on six motorbikes within 60 days. The new sampling location tracking approach is effective in terms of cost, time, human resource requirements, thus can be adopted in large-scale soil/plant sampling frames with high accuracy.
暂无评论