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Pulse crops such as chickpeas, lentils, and dry peas are grown widely for human and animal consumption. Major yield and quality limiting constraints include diseases caused by fungi and oomycetes. The environmental and health concerns of synthetic fungicides use for disease management, emergence of fungicide-resistant pathogens, and demand for organic pulse crop products necessitate the search for effective alternatives. Safe and environmentally friendly plant-derived essential oils (EOs) have been reported effective against some pathogenic fungi. Growth on EO amended growth medium and an inverted Petri-plate assay were used to determine the effects of 38 oils and their volatiles on mycelial growth and spore germination of important pathogenic fungi and oomycetes: Aphanomyces euteiches, Botrytis cinerea, Colletotrichum lentis, Didymella pisi, D. rabiei, D. lentis, Fusarium avenaceum, Stemphylium beticola, Sclerotinia sclerotiorum, and Pythium sylvaticum. Palmarosa, oregano, clove, cinnamon, lemongrass, citronella, and thyme oils incorporated in media inhibited mycelial growth of all the pathogens by 100% at 1:1,000 to 1:4,000 dilution. In addition, thyme oil (1:500 dilution) showed complete inhibition of conidial germination (0% germination) of F. avenaceum, and D. pisi. All the seven EO volatiles inhibited mycelial growth of all pathogens by 50 to 100% except for B. cinerea and S. sclerotiorum. Essential oil effects on mycelial growth were fungistatic, fungicidal or both and varied by E. Essential oils show potential for management of major crop diseases in organic and conventional production systems.

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Powdery mildew caused by Erysiphe pulchra is one of the most destructive diseases of flowering dogwoods (Cornus florida L.). Control of powdery mildew relies heavily on chemical fungicides. Developing genetic resistance and planting powdery mildew resistant cultivars is a desirable long term control strategy for the disease.Information on inheritance characteristics associated with powdery mildew resistance in C. florida is needed to facilitate development of breeding strategies for a new generation of powdery mildew resistant cultivars. The objectives of this study were to determine broad-sense heritability, genetic gain and minimum number of effective genes associated with resistance to powdery mildew in C. florida. Progeny segregating for powdery mildew resistance were developed through controlled crosses between susceptible cultivar [Cherokee Princess (CP)], resistant selection (R14) and moderately resistant cultivars [MI9 and Cherokee Brave (CB)]. The parents and progeny were evaluated for resistance/ susceptibility to powdery mildew under greenhouse conditions and estimates for broad-sense heritability, genetic gain and minimum number of effective genes was determined. Broad-sense heritability ranged from 60% to 88% while corresponding narrow-sense heritability ranged from 53% to 86.6%. The highest predicted genetic gain for powdery mildew resistance was obtained in the R14 x CP (78%) and CB x MI9 (61%) crosses while the lowest genetic gain was observed in the CP x MI9 (34%) and MI9 x CB (36%) crosses.These results indicate that CB x MI9 and R14 x CP crosses are best parental lines for developing resistance to powdery mildew among the genotypes tested. Use of these parental lines and understanding the gene flow of resistance to powdery mildew in dogwoods will help researchers to develop a targeted breeding approach in generating new generation of resistant cultivars.