The etiology of head rot disease of broccoli

Transmission and scanning electron microscope studies of broccoli florets affected by head rot, at various stages of disease development, strongly indicated a bacterial etiology for the disease. Nevertheless, the different species of bacteria isolated from diseased heads, using standard techniques, failed to reproduce symptoms in pathogenicity tests conducted in the glasshouse and in the field. However, a modified isolation technique, using broccoli heads showing incipient watersoaking symptoms, yielded a fluorescent pseudomonad which reproduced disease symptoms readily in glasshouse and field tests. On the basis of physiological and biochemical characters, the pathogenic bacterium was identified as a highly pectolytic pathovar of Pseudomonas marginalis. The bacterium also caused the rotting of potato, tomato and swede turnip slices, and also of intact and detached tomato fruit. However, it was not pathogenic on lettuce, parsnip or lucerne, and also failed to rot carrot slices

Cost Benefit Analysis of Utilising Mobile Nodes in Wireless Sensor Networks

Mobile nodes have been found useful for improving performanceof network parameters such as coverage, data latency and load balancing inwireless sensor networks (WSNs). In spite of the benets which mobile nodescould oer when used in WSNs, they have been often stated as infeasible foruse. As they are expensive compared to static nodes in terms of manufactur-ing and mobility cost. This paper evaluates the utility of mobile nodes foruse in WSNs in comparison with static nodes. Novel geometric models to rep-resent the various functionalities for which mobile could be used have beenproposed, they have been utilised for the techno-economic evaluation basedon cost benet analysis. The models have been designed such that they givea generic representation of the functionalities, and enable a fair comparisonbetween them. On the basis of the analysis it is concluded that apart from thefunctional utility, mobile nodes are economically benecial for use in WSNs