806 research outputs found
Validation of Molecular Markers Genetically Linked to S-Cytoplasm and Restoration-of-fertility (Rf) Loci in Hot Pepper (Capsicum annuum L.)
Existence of CGMS system in hot pepper is due to the rearrangements in the mitochondrial genome and is largely used in economized and pure F 1 hybrid seed production around the world. The orf456, a new ORF present at flanking region of the coxII gene at the 3’ end, was distinguished male sterile cytoplasm in hot peppers along with atp6-2gene. In the current study, eighteen pepper genotypes (nine each of A and corresponding B lines) of varied origin were used to validate with two male sterile cytoplasm (S-cytoplasm) specific sequence characterised amplified region (SCAR) markers viz., atp6-2 (875 bp) and orf456 (456 bp) and one restoration-of-fertility (Rf) locus specific marker, CRF (550 bp). The results clearly showed that the presence of CMS-S-cytoplasm and absence of restoration-of-fertility (Rf) gene in the pepper genotypes studied and is comparable with the phenotypic data. In view of the outcomes it has been reasoned that the accessible S and Rf markers available in the public domain are reproducible and can be promptly utilized for marker assisted selection (MAS) in hot pepper crop improvement program
Unusual Dynamical Scaling in the Spatial Distribution of Persistent Sites in 1D Potts Models
The distribution, n(k,t), of the interval sizes, k, between clusters of
persistent sites in the dynamical evolution of the one-dimensional q-state
Potts model is studied using a combination of numerical simulations, scaling
arguments, and exact analysis. It is shown to have the scaling form n(k,t) =
t^{-2z} f(k/t^z), with z= max(1/2,theta), where theta(q) is the persistence
exponent which characterizes the fraction of sites which have not changed their
state up to time t. When theta > 1/2, the scaling length, t^theta, for the
interval-size distribution is larger than the coarsening length scale, t^{1/2},
that characterizes spatial correlations of the Potts variables.Comment: RevTex, 11 page
Evaluation of Solanum species and eggplant cultivated varieties for bacterial wilt resistance
Bacterial wilt caused by Ralstonia solanacearum is one of the major diseases in Solanum species including cultivated Eggplant (Solanum melongena L.). Bacterial wilt (BW) disease management in eggplant is difficult due to high survival rate of pathogen in soil and chemical application is not eco-friendly. The best way to avoid bacterial wilt in eggplant is using disease-resistant varieties. However, only a limited number of bacterial wilt resistant varieties are available and, there is a necessity to identify and/or develop new resistant varieties. In the current study, wild Solanum species, and eggplant cultivated varieties were evaluated against Ralstonia solanacearum, and disease incidence was recorded. The cultivated varieties IIHR-108, Pusa Purple Long and Rampur Local were identified as susceptible, whereas, IIHR-7 and CARI-1 were identified as resistant to bacterial wilt. These resistant wild and cultivated varieties can be used as a root-stock in bacterialwilt disease resistant breeding programmes
Persistence in Cluster--Cluster Aggregation
Persistence is considered in diffusion--limited cluster--cluster aggregation,
in one dimension and when the diffusion coefficient of a cluster depends on its
size as . The empty and filled site persistences are
defined as the probabilities, that a site has been either empty or covered by a
cluster all the time whereas the cluster persistence gives the probability of a
cluster to remain intact. The filled site one is nonuniversal. The empty site
and cluster persistences are found to be universal, as supported by analytical
arguments and simulations. The empty site case decays algebraically with the
exponent . The cluster persistence is related to the
small behavior of the cluster size distribution and behaves also
algebraically for while for the behavior is
stretched exponential. In the scaling limit and with fixed the distribution of intervals of size between
persistent regions scales as , where is the average interval size and . For finite the
scaling is poor for , due to the insufficient separation of the two
length scales: the distances between clusters, , and that between
persistent regions, . For the size distribution of persistent regions
the time and size dependences separate, the latter being independent of the
diffusion exponent but depending on the initial cluster size
distribution.Comment: 14 pages, 12 figures, RevTeX, submitted to Phys. Rev.
Screening of recombinant inbred lines for resistance to bacterial leaf blight pathotypes in rice (Oryza sativa L.)
In the present investigation 16 recombinant inbred lines (RIL’s) developed from the intra-specific cross between YH3 and AKDRMS 21-54 through Marker Assisted Pedigree Breeding Method were screened along with their parents and the checks, namely, BPT 5204, TN1 and Improved Samba Mahsuri (ISM) against IxoPt-20 pathotype at the ICAR-Indian Institute of Rice Research, Hyderabad during Rabi 2021-22 and a new pathotype of Xanthomonas oryzae pv. oryzae causing Bacterial Leaf Blight disease in rice at Regional Agricultural Research Station, Maruteru during Kharif 2022 to identify pathotype specific resistant sources. Morpho-Molecular screening was adopted to evaluate the recombinant inbred lines over two locations in the consecutive seasons of Rabi 2021-22 and Kharif 2022. Based on per cent diseased leaf area, the genotypes were scored and categorised as per the Standard Evaluation System (SES) scale provided by International Rice Research Institute (IRRI). The results revealed all 16 RIL’s to be either resistant (10) or moderately resistant (6) to IxoPt-20 pathotype. However, only five RIL’s were found to be resistant, while four RIL’s were moderately resistant for the new virulent pathotype. Seven RIL’s with resistant to moderately resistant reaction for IxoPt-20 pathotype, showed moderately susceptible reaction for the new virulent pathotype. Among the resistant RIL’s identified for each pathotype, BPT-1901-72-10-6, BPT-1901-108-4-1 and BPT-1901-111-3-2 were found to be uniformly resistant, while, BPT-1901-45-8-6 and BPT-1901-163-1-18 were uniformly moderately resistant to both IXoPt-20 and the new virulent pathotype at Hyderabad and Maruteru, respectively, indicating their potential as genetic stocks for development of new cultivars resistant to bacterial leaf blight disease
Persistence in the One-Dimensional A+B -> 0 Reaction-Diffusion Model
The persistence properties of a set of random walkers obeying the A+B -> 0
reaction, with equal initial density of particles and homogeneous initial
conditions, is studied using two definitions of persistence. The probability,
P(t), that an annihilation process has not occurred at a given site has the
asymptotic form , where is the
persistence exponent (``type I persistence''). We argue that, for a density of
particles , this non-trivial exponent is identical to that governing
the persistence properties of the one-dimensional diffusion equation, where
. In the case of an initially low density, , we find asymptotically. The probability that a site
remains unvisited by any random walker (``type II persistence'') is also
investigated and found to decay with a stretched exponential form, , provided . A heuristic argument
for this behavior, based on an exactly solvable toy model, is presented.Comment: 11 RevTeX pages, 19 EPS figure
Direct Instantons in QCD Nucleon Sum Rules
We study the role of direct (i.e. small-scale) instantons in QCD correlation
functions for the nucleon. They generate sizeable, nonperturbative corrections
to the conventional operator product expansion, which improve the quality of
both QCD nucleon sum rules and cure the long-standing stability problem, in
particular, of the chirally odd sum-rule.Comment: 10 pages, UMD PP#93-17
Different atmospheric moisture divergence responses to extreme and moderate El Niños
On seasonal and inter-annual time scales, vertically integrated moisture divergence provides a useful measure of the tropical atmospheric hydrological cycle. It reflects the combined dynamical and thermodynamical effects, and is not subject to the limitations that afflict observations of evaporation minus precipitation. An empirical orthogonal function (EOF) analysis of the tropical Pacific moisture divergence fields calculated from the ERA-Interim reanalysis reveals the dominant effects of the El Niño-Southern Oscillation (ENSO) on inter-annual time scales. Two EOFs are necessary to capture the ENSO signature, and regression relationships between their Principal Components and indices of equatorial Pacific sea surface temperature (SST) demonstrate that the transition from strong La Niña through to extreme El Niño events is not a linear one. The largest deviation from linearity is for the strongest El Niños, and we interpret that this arises at least partly because the EOF analysis cannot easily separate different patterns of responses that are not orthogonal to each other. To overcome the orthogonality constraints, a self-organizing map (SOM) analysis of the same moisture divergence fields was performed. The SOM analysis captures the range of responses to ENSO, including the distinction between the moderate and strong El Niños identified by the EOF analysis. The work demonstrates the potential for the application of SOM to large scale climatic analysis, by virtue of its easier interpretation, relaxation of orthogonality constraints and its versatility for serving as an alternative classification method. Both the EOF and SOM analyses suggest a classification of “moderate” and “extreme” El Niños by their differences in the magnitudes of the hydrological cycle responses, spatial patterns and evolutionary paths. Classification from the moisture divergence point of view shows consistency with results based on other physical variables such as SST
Observed Reductions in Schistosoma mansoni Transmission from Large-Scale Administration of Praziquantel in Uganda: A Mathematical Modelling Study
To date schistosomiasis control programmes based on chemotherapy have largely aimed at controlling morbidity in treated individuals rather than at suppressing transmission. In this study, a mathematical modelling approach was used to estimate reductions in the rate of Schistosoma mansoni reinfection following annual mass drug administration (MDA) with praziquantel in Uganda over four years (2003-2006). In doing this we aim to elucidate the benefits of MDA in reducing community transmission.Age-structured models were fitted to a longitudinal cohort followed up across successive rounds of annual treatment for four years (Baseline: 2003, TREATMENT: 2004-2006; n = 1,764). Instead of modelling contamination, infection and immunity processes separately, these functions were combined in order to estimate a composite force of infection (FOI), i.e., the rate of parasite acquisition by hosts.MDA achieved substantial and statistically significant reductions in the FOI following one round of treatment in areas of low baseline infection intensity, and following two rounds in areas with high and medium intensities. In all areas, the FOI remained suppressed following a third round of treatment.This study represents one of the first attempts to monitor reductions in the FOI within a large-scale MDA schistosomiasis morbidity control programme in sub-Saharan Africa. The results indicate that the Schistosomiasis Control Initiative, as a model for other MDA programmes, is likely exerting a significant ancillary impact on reducing transmission within the community, and may provide health benefits to those who do not receive treatment. The results obtained will have implications for evaluating the cost-effectiveness of schistosomiasis control programmes and the design of monitoring and evaluation approaches in general
Green supply chain performance measurement using fuzzy ANP-based balanced scorecard:a collaborative decision-making approach
The purpose of this paper is to delineate a green supply chain (GSC) performance measurement framework using an intra-organisational collaborative decision-making (CDM) approach. A fuzzy analytic network process (ANP)-based green-balanced scorecard (GrBSc) has been used within the CDM approach to assist in arriving at a consistent, accurate and timely data flow across all cross-functional areas of a business. A green causal relationship is established and linked to the fuzzy ANP approach. The causal relationship involves organisational commitment, eco-design, GSC process, social performance and sustainable performance constructs. Sub-constructs and sub-sub-constructs are also identified and linked to the causal relationship to form a network. The fuzzy ANP approach suitably handles the vagueness of the linguistics information of the CDM approach. The CDM approach is implemented in a UK-based carpet-manufacturing firm. The performance measurement approach, in addition to the traditional financial performance and accounting measures, aids in firms decision-making with regard to the overall organisational goals. The implemented approach assists the firm in identifying further requirements of the collaborative data across the supply-cain and information about customers and markets. Overall, the CDM-based GrBSc approach assists managers in deciding if the suppliers performances meet the industry and environment standards with effective human resource
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