Development of an alternative device for measurement and characterization of selected meteorological parameters

Weather monitoring and forecasting during some of nature's most violent events, such as lightning and thunder, necessitates immediate preventive action for improved agricultural precision, power equipment effectiveness among others. Weather stations that are all-in-one for villages, low-income communities, and cities could provide a dependable, cost-effective, robust, and user-friendly solution. A wide range of low-cost weather monitoring stations equipped with ground-based and satellite-based lightning detectors are available on the market. This paper develops a low-cost real-time data logger device that measures lightning strikes and other weather parameters. Temperature and relative humidity are detected and recorded by the sensor (BME280). The sensing unit, readout circuit unit, microcontroller unit, recording unit, real-time clock, display unit, and power supply unit are the seven sections of the lightning detector with a real-time data logger. The sensing unit of the instrument is made of a lightning sensor glued to a polyvinyl chloride (PVC) to prevent moisture inflow and short circuit. The readout circuit consists of a 16-bit analog-to-digital converter and a filter designed to improve the output signal of the lightning detector. It was programmed with C-language and tested using the integrated development environment on the Arduino-Uno microcontroller (IDE). The device was calibrated, and its accuracy was determined using data from a standard lightning detector instrument from the Nigerian Meteorological Agency (NIMET).

Genetic mapping of a dominant gene conferring resistance to cassava mosaic disease

Cassava mosaic disease (CMD) is the most-important disease of cassava ( Manihot esculenta) in Africa, and is a potential threat to Latin American (LA) cassava production. Although this viral disease is still unknown in LA, its vector - the whitefly - has recently been found. The disease is best controlled through host-plant resistance, which was first found in third backcross derivatives of an interspecific cross between cassava and Manihot glaziovii, and is thought to be polygenic. Recently, high levels of resistance were also found in several Nigerian cassava landraces. Classical genetic analysis and molecular genetic-mapping of the landraces showed that a major dominant gene confers this resistance. Bulk segregant analysis (BSA) was used to quickly identify a simple sequence repeat (SSR) marker linked to the CMD-resistance gene. The marker, SSRY28, is located on linkage group R of the male-parent-derived molecular genetic map. The gene, designated as CMD2, is flanked by the SSR and RFLP marker GY1 at 9 and 8 cM, respectively. To our knowledge, this is the first report of qualitative virus resistance in cassava, and of molecular markers that tag CMD resistance in cassava. We discuss the use of markers linked to CMD2 for marker-assisted breeding of CMD resistance in Latin America and for increasing the cost-effectiveness of resistance breeding in Africa.