Botrytis grey mould (BGM), caused by Botrytis cinerea Pers. ex. Fr., is an economically important disease of chickpea (Cicer arietinum L.), especially in areas where cool, cloudy, and humid weather persists. Several epidemics of BGM causing complete crop loss in the major chickpea-producing countries have been reported. The pathogen B. cinerea mainly survives between seasons on infected crop debris and seeds. Despite extensive investigations on pathological, physiological, and molecular characteristics of B. cinerea causing grey mould type diseases on chickpea and several other hosts, the nature of infection processes and genetic basis of pathogen variability have not been clearly established. This lack of information coupled with the need for repeated application of chemical fungicides forced the deployment of host plant resistance (HPR) as a major option for BGM management. Effective and repeatable controlled-environment and field-screening techniques have been developed for identification of HPR. Of the selected portion of chickpea germplasm evaluated for BGM resistance, only few accessions belonging to both cultivated and wild Cicer spp. were tolerant to BGM, and the search for higher levels of disease resistance continues. Fungicide application based on disease predictive models is helpful in precision-based fungicide application. Integrated disease management (IDM) of BGM has proved more effective than any of the individual disease management components in large-scale, on-farm studies conducted in India, Nepal, and Bangladesh. Further information on the biology of B. cinerea and epidemiology of the disease is needed to strengthen the IDM programs. In this paper the biology of B. cinerea including its variability, epidemiology of BGM, identified sources of resistance, and other management options, and available information on biochemical and genetic basis of disease resistance have been reviewed with a mention of future research priorities.

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Pattern of disease spread provides improved knowledge on how the pathogen introduces itself and interacts with environment in fields and expresses as a disease. It is especially significant when epidemiology of a disease, such as Rice False Smut (RFSm), is unclearly understood. Not reported before, this study attempted an analysis of spatial pattern of natural spread of RFSm in nine fields in an intensive rice ecosystem in Bangladesh. Both conventional and specialized statistical methods were applied in the analysis. Results show that the spread of the disease was not similar between and within the fields and even some fields were almost disease free. RFSm recorded aggregation in spaces in most of the fields, but the location of this aggregation differed between the fields. Symptom recorded on panicles in regenerated tillers from harvested main crop (otherwise known as ratoons). The disease tended to be prominent towards proximity of drainage channels. The probability of occurring one diseased tiller per hill was calculated as 73% and cumulative probability of four or less smut balls per diseased panicle as little over 60%. This study establishes soil as the absolute dominant source of initiation of the epidemic. The analysis did not find evidence of any long-or short-distance primary and/or secondary sources of infection. It is concluded that the disease management be directed specific to the fields at risk. It suggests development of a soil testing tool for quantifying inoculum potential in a field to ascertain the risk. With the discovery of symptom on ratoons, this study highlights the need for fresh thinking on identifying the pathway of entry of the pathogen into the plant.

Rice False Smut (RFSm) is presently an internationally important fungal disease of rice. While the Yield Loss (YL) from this disease is reported in many countries, there exists no tool to instantly estimate the YL by visual field inspection. This study developed a simple model, FLYER, for this purpose. The model is run by two inputs: (i) fraction of productive but diseased tillers in a field and (ii) averaged number of smut balls present in the diseased panicles. FLYER was developed using data from Bangladesh, India and Japan. The driving algorithm of the model, the yield reduction in a diseased panicle as a function of number of smut balls present in the panicle, was validated with additional data from Bangladesh and Japan. When tested with independent data from fields infected naturally by RFSm, FLYER closely estimated the Yield Loss (YL, %) against observed datasets from Bangladesh (Root Mean Squared Deviation (RMSD) = 1.15% YL), Egypt (RMSD = 1.65% YL) and India (RMSD = 1.68% YL). This model could contribute to rapid assessment of regional and variety-specific yield loss and strategic management of the disease on a field-by-field basis.

Pulse crops in Australian broad-acre agriculture are a relatively small but essential component of presentday farming systems. Winter pulses, particularly the five accounted for in this review, dominate pulse area and production in this country. The Australian pulse industry has experienced devastating epidemics of diseases such as lupin anthracnose and chickpea ascochyta blight. In addition, many other diseases have appeared regionally. Research on various aspects was directed towards managing these diseases in individual regions, states and nationally. This review addresses advances in pathology related to bacterial, fungal and viral pathogens in lupins, chickpeas, field peas, lentils and faba beans. In addition to fundamental epidemiological and disease control studies, this paper includes molecular studies and quantitative epidemiology leading to disease modelling and disease forecasting. It also highlights the efforts undertaken recently by pulse pathologists in Australia to strengthen collaborative research nation-wide.