Time filter

Source Type


Bajracharya J.,NARC | Brown A.H.D.,CSIRO | Joshi B.K.,Biotechnology Unit | Panday D.,Seed Quality Control Center | And 3 more authors.
Genetic Resources and Crop Evolution | Year: 2011

Chawali and Lekali are two common farmer's barley varieties or landraces in Jumla, Nepal (2,240-3,000 m) with small to bold grains and wide adaptation from irrigated low lands to high hills. This study was undertaken to test whether features of the traditional seed system can significantly influence the diversity of a crop and its conservation on-farm. In Jumla (high-hill), the barley seed system is completely informal and is mainly from farmer to farmer. In the present study, the seed flows and the pattern of genetic diversity in barley were investigated to detect differences between the two varieties and test the divergence among populations of each variety These data suggested that Chawali, the more common variety, was less subject to homogenising gene flow between farms than was Lekali. A total of 128 farming households were surveyed for seed supply information and 128 populations for each landrace from two villages: Kartikswami and Talium were collected for SSR diversity analysis. Some 92 SSRs were screened in an initial sample of 20 barley populations of both landraces and 2 improved varieties (LG-51 and Soluwa). Of the 81 SSRs that consistently amplified, only 15 SSRs (19%) were polymorphic with gene diversity values ranging from 0.09 to 0.71. A medium to low diversity was detected among the landrace populations of barley varieties. Chawali populations were less polymorphic within ecological groups, and more divergent between than were Lekail populations. This result accords with Chawali having a more conservative local seed system. © 2011 Springer Science+Business Media B.V. Source

Manzoor F.,Lahore College for Women University | Chaudhary M.,Lahore College for Women University | Sheikh N.,University of Punjab | Khan I.A.,University of Peshawar | Khan T.,NARC
Pakistan Journal of Zoology | Year: 2011

The diversity and proportions of termite species was studied in a wheat crop and garden trees from January to June, 2006 in District Bhakkar. Six species of termites i.e., Coptotermes heimi, Microcerotermes spp., Odontotermes obesus, Microtermes obesi, Microtermes mycophagus and Odontotermes guptai were recorded from wheat fields and garden trees. Termite species inhabited different portions of trees. The results also provided a comparison between the termite species diversity in wheat crop and garden trees. Diversity of termites recovered from soil cores' revealed 35% diversity on the Simpson index and 84% on the Shannon scale. M. mycophagus was the dominant termite species in both garden trees as well as wheat crop. The six species variably inhabit different portions of garden trees. Copyright 2011 Zoological Society of Pakistan. Source

Kaloi G.M.,National Sugar and Tropical Horticulture Research Institute | Mari A.H.,National Sugar and Tropical Horticulture Research Institute | Zubair M.,NARC | Panhwar R.N.,National Sugar and Tropical Horticulture Research Institute | And 4 more authors.
Journal of Animal and Plant Sciences | Year: 2014

A comparative study was conducted to assess the performance of ten exotic sugar beet varieties on four locations of lower Sindh. Soils of the experimental locations were clay and clay loam in texture, alkaline in reaction and saline in nature. The experiment was laid out according to a randomized complete block design (RCBD) with three replications. All sugar beet varieties showed different behavior with respect to beet yield and sugar recovery. Maximum beet yield was produced by SDPAK 03/06 followed by California, Magnolia and SDPAK 09/07. In terms of sugar recovery, the varieties Magnolia, SDPAK 01/07, SDPAK 07/07 and SDPAK 09/07 performed better and were almost at par. While, the varieties California, Magnolia, SDPAK 03/04 and SDPAK 09/07 performed best with regard to beet yield and sugar recovery. The results illustrated that sugar beet can be successfully grown on saline soils of lower Sindh. The sugar beet cultivation on marginal soils will bring more economic returns to growers as compared to cultivation of others especially sugarcane. Source

Nawab N.N.,University of Agriculture at Faisalabad | Saeed A.,University of Agriculture at Faisalabad | Tariq M.S.,NARC | Nadeem K.,Vegetable Research Institute | And 6 more authors.
African Journal of Biotechnology | Year: 2011

Okra leaf (L 0L 0) cottons confer resistance/non-preference against insect pests. The inheritance of this trait was studied in three cross combinations involving a common okra leaf parent (HRVO-1) with three normal leaf (l 0l 0) parents (FH-1000, CIM-446 and Acala 63-74). The non-significant x 2 in F 2 for leaf shapes in all the crosses fit well against the theoretical monohybrid ratio of 1:2:1 showing incomplete dominance. Observations of 1 okra leaf (L 0L 0): 2 an intermediate class of sub-okra (L 0l 0): 1 normal leaf (l 0l 0) were observed in the F 2 populations of the three crosses. In the backcross generations with parent- I, ratios of 1 okra leaf: 1 sub-okra, leaf morphologies were obtained. Similarly, in the backcrosses with parent-II, ratios of 1 normal leaf: 1 sub-okra, an intermediate class of leaf shape were observed. The discontinuous variation for leaf shape in F 2 generations of three crosses observed in the frequency distribution confirmed the qualitative inheritance for this trait. The incorporation of the gene for okra leaf type had no significant effect on the major fibre quality attributes like fibre length, fibre strength, lint percentage, fibre uniformity ratio and fibre fineness. Number of sympodial branches/plant, number of bolls/plant, boll weight and seed cotton yield/plant principal yield assuring traits showed improvement, with the incorporation of the gene for okra leaf type. The gene for okra leaf type can be incorporated in a genotype that covers the insect non-preference and yield enhancements without increasing number of monopodial branches. The justification for the increase in yield and its components is due to the okra leaf morphology conferring resistance/non-preference against insect pests with reduced leaf area allowing better air flow and maximum sunlight penetration through the leaves of the plant. © 2011 Academic Journals. Source

Kannan S.R.,Pondicherry University | Devi R.,Pondicherry University | Ramathilagam S.,Periyar Government College | Takezawa K.,NARC
Computers in Biology and Medicine | Year: 2013

The main motivation of this paper is to introduce a class of robust non-Euclidean distance measures for the original data space to derive new objective function and thus clustering the non-Euclidean structures in data to enhance the robustness of the original clustering algorithms to reduce noise and outliers. The new objective functions of proposed algorithms are realized by incorporating the noise clustering concept into the entropy based fuzzy C-means algorithm with suitable noise distance which is employed to take the information about noisy data in the clustering process. This paper presents initial cluster prototypes using prototype initialization method, so that this work tries to obtain the final result with less number of iterations. To evaluate the performance of the proposed methods in reducing the noise level, experimental work has been carried out with a synthetic image which is corrupted by Gaussian noise. The superiority of the proposed methods has been examined through the experimental study on medical images. The experimental results show that the proposed algorithms perform significantly better than the standard existing algorithms. The accurate classification percentage of the proposed fuzzy C-means segmentation method is obtained using silhouette validity index. © 2012 Elsevier Ltd. Source

Discover hidden collaborations