Operational Challenges in Conducting a Subnational TB Prevalence Survey in India: Lessons Learned for Resource-Limited, High-Burden Settings

Estimating the burden of TB at the subnational level is critical to planning and prioritizing resources for TB control activities according to the local epidemiological situation. We report the experiences and operational challenges of implementing a TB prevalence survey at the subnational level in India. Information was collected from research reports that gathered data from periodic meetings, informal discussions with study teams, letters of communication, and various site visit reports. During the implementation of the survey, several challenges were encountered, including frequent turnover in human resources, lack of survey participation and community engagement, breakdown of X-ray machines, laboratory issues that delayed sputum sample testing, delays in X-ray reading, and network and Internet connectivity issues that impeded data management. To help ensure the survey was implemented in a timely manner, we developed several solutions, including planning ahead to anticipate challenges, ensuring timely communication, having a high commitment from all stakeholders, having strong team motivation, providing repetitive hands-on training, and involving local leaders to increase community engagement. This experience may help future states and countries that plan to conduct TB prevalence surveys to address these anticipated challenges and develop alternative strategies well in advance

Optimization of in vitro regeneration and microcorm induction in elephant foot yam (Amorphophallus paeoniifolius)

Elephant foot yam (Amorphophallus paeoniifolius) is a vegetatively propagated stem tuber crop. In this investigation we describe a highly competent and reproducible in vitro propagation of the plant from corm bud, petiole and young leaf explants. Friable callus was initiated from all the explants on modified MS medium (half the concentration of NH4NO3 and KNO3) supplemented with 0.5 mg l-1 each of benzyl amino purine (BAP), α-naphthalene acetic acid (NAA) and 2,4-dichloro phenoxy acetic acid (2,4-D). Shoot regeneration from calli was optimal on modified MS medium supplemented with 5.0 mg l-1 BAP and 1.0 mg l-1 NAA. Microcorms, capable of producing micro shoots all over the surface, were induced from the callus at a frequency of 90% on shoot regeneration medium supplemented with 5% sucrose. Rooting was 100% on modified liquid MS medium augmented with 5.0 mg l-1 Indole 3- butyric acid (IBA). A 100% survival rate of plantlets on transplantation to soil: sand: coir pith mixture was recorded.Keywords: Callus, elephant foot yam, in vitro, microcorms, regeneration, somatic embryoAfrican Journal of Biotechnology, Vol 13(49) 4508-451

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Next-generation sequencing reveals endosymbiont variability in cassava whitefly, Bemisia tabaci, across the agro-ecological zones of Kerala, India

Silverleaf whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), is one of the most notorious invasive insect pests reported, infesting more than 900 species of plants and spreading more than 200 viral diseases. This polyphagous agricultural pest harbours diverse bacterial communities in its gut, which perform multiple functions in whiteflies, including nutrient provisioning, amino acid biosynthesis and virus transmission. The present exploratory study compares bacterial communities associated with silverleaf whitefly infesting cassava, also known as cassava whitefly, collected from two different zones (zone P: plains, zone H: high ranges), from Kerala, India, using next-generation sequencing of 16S rDNA. The data sets for these two regions consisted of 1,321,906 and 690,661 high quality paired end sequences with mean length of 150 bp. Highly diverse bacterial communities were present in the sample containing approximately 3,513 operational taxonomic units (OTUs). Sequence analysis had shown a marked difference in the relative abundance of bacteria in the populations. A total of 16 bacterial phyla, 27 classes, 56 orders, 91 families, 236 genera and 409 species were identified from P population, against 16, 31, 60, 88, 225 and 355, respectively in H population. Arsenophonus sp. (Enterobacteriaceae), which is important for virus transmission by whiteflies, was relatively abundant in P population, whereas in H population Bacillus sp. was the most dominant group. The association of whitefly biotypes and secondary symbionts suggests a possible contribution of these bacteria to host characteristics such as virus transmission, host range, insecticide resistance and speciationThe accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

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Not AvailableSilverleaf whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), is one of the most notorious invasive insect pests, infesting more than 900 species of plants and spreading more than 200 viral diseases. This polyphagous agricultural pest harbours diverse bacterial communities in its gut, which perform multiple functions in whiteflies, including nutrient provisioning, amino acid biosynthesis, and virus transmission. The present exploratory study compares the bacterial communities associated with silverleaf whitefly infesting cassava, also known as cassava whitefly, collected from two different zones (zone P: plains; zone H: high ranges), from Kerala, India, using nextgeneration sequencing of 16S rDNA. The data sets for these two regions consisted of 1 321 906 and 690 661 high-quality paired-end sequences with mean length of 150 bp. Highly diverse bacterial communities were present in the sample, containing approximately 3513 operational taxonomic units (OTUs). Sequence analysis showed a marked difference in the relative abundance of bacteria in the populations. A total of 16 bacterial phyla, 27 classes, 56 orders, 91 families, 236 genera, and 409 species were identified from the P population, against 16, 31, 60, 88, 225, and 355, respectively, in the H population. Arsenophonus sp. (Enterobacteriaceae), which is important for virus transmission by whiteflies, was relatively abundant in the P population, whereas in the H population Bacillus sp. was the most dominant group. The association of whitefly biotypes and secondary symbionts suggests a possible contribution of these bacteria to host characteristics such as virus transmission, host range, insecticide resistance, and speciation.ICA

Investigation into Mechanical Properties and Sliding Wear Behavior of Friction Stir Processed Surface Composite Material

One of the different and pioneering solid-state techniques, friction stir processing (FSP), is employed for the production of surface composites. In this research, the matrix selected was copper-nickel (CuNi) with hard boron carbide particle as reinforcement. The objective of the current research work is to produce reinforced 90/10 copper-nickel surface composites reinforced with B4C fabricated via FSP. The influence of tool rotational speed on macrostructure, microstructure, grain size analysis, microhardness, and wear studies of friction stir processed (FSPed) CuNi/B4C surface composites was assessed. For high rotational speed (1400 rpm) of stir tool, the modified surface area found is a maximum of 44.4 mm2 with uniform dispersion of hard particle reinforcement. The presence of hard particle in the surface area is revealed through the electron imaging and the spectroscopic results. Spectra mapping shows the uniform distribution of hard particle over the FSPed area, and the evidence is obtained with XRD analysis. From the experimentation, it is interesting to report that the reinforcements have decreased the surface hardness for an increased rotational speed of stir tool. The hardness recorded for minimum rotational speed is 223 HV which has gradually decreased to 178 HV for 1300 rpm. It has directly influenced the wear rate of modified FSPed, as hardness is directly proportional to wear behavior. The worn surface and fractured morphology of the CuNi/B4C surface composites were also studied using Field Emission Scanning Electron Microscope (FESEM)

Distribution of Papaya Ring Spot Virus Infecting Papaya in Kerala, India

In the midst of the rising interest of papaya cultivation in Kerala, it is inevitable to study the current status of the Papaya ring spot disease in the state. Knowing the severity and distribution of PRSV isolates, causing ring spot disease, helps in the better formulation of effective management strategies against it. Purposive sampling surveys carried out in 2021-22 across five agro ecological units (AEUs) of Kerala, recorded papaya ring spot disease incidence (PRSD) ranging from 50 to 100 per cent in the cultivated areas with vulnerability index of 33.54 to 98.22. Highest disease incidence was recorded from AEU 8- Southern Laterites: Thiruvananthapuram (100.0%) and highest vulnerability index was recorded from Kalliyoor (98.22). Twenty symptomatic samples tested positive for PRSV in double antibody sandwich- ELISA (DAS-ELISA) using PRSV polyclonal antiserum. RT-PCR using coat protein gene specific primers RKJ 52 and 3 yielded amplicons of size approximately ~890bp in all the samples. Virulence of the Kerala isolates was evaluated based on the symptom expression, disease incidence and vulnerability index, upon mechanical transmission of PRSV on two months old papaya plants (variety- Red Lady). PRSV isolate from Kalliyoor (TVM1) inoculated on papaya plants expressed chlorosis, mottling, malformation of leaves and stunting with 96.80 vulnerability index. Maximum vulnerability index and severe symptoms including stunting in the inoculated plants were observed in isolates from southern and central Kerala, which include Thiruvananthapuram, Alappuzha and Thrissur had the most virulent PRSV isolates compared to north Kerala