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Alternaria blight is one of the most deadly diseases of oilseed Brassica. This recalcitrant disease causes up to 50% yield loss across the globe. The disease is mainly caused by Alternaria brassicae and Alternaria brassicicola. These pathogens lack sexual stages and survive as conidia or condiospores on the debris of previous crops and susceptible weeds. Developing resistant oilseed Brassica cultivars to this disease has become a prime concern for researchers over the years. In absence of resistant oilseed Brassica cultivar, identification and introgression of resistance related genes can be a potential source for Alternaria blight resistance. As resistance toward Alternaria blight is governed by polygenes, intercrossing between the tolerant genotypes and subsequent selection will be the most appropriate way to transfer the quantitative resistance. For that reason, future breeding goal should focus on screening of germplasms for selecting genotypes containing resistance genes and structural features that favors resistance, like thick epicuticular wax, biochemical components such as phenols, phytoalexins and lower soluble sugars, reducing sugars and soluble nitrogen. Selected genotypes should be brought under appropriate breeding programs for attaining Alternaria blight resistance.

Interspecific hybridization creates new genetic variants. Embryo formation and subsequently fertile seed development are the indicators of successful interspecific hybridization. Often interspecific hybridization is limited due to variations in genome and ploidy levels. The technique of embryo rescue is commonly used in interspecific hybridization to facilitate the survival of embryos from abortion. The effectiveness of an embryo rescue program in the Brassica species depends on embryo age, embryo development stage and media composition. Embryo rescue protocol could be effectively utilized to solve some major problems of the oilseed Brassica growers including blackleg, clubroot and Alternaria disease resistance, salinity, and drought tolerance etc. This review article discusses the prospects of developing novel Brassica hybrid genotypes with desirable traits through embryo rescue.

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