In the world of agriculture, the cultivation of Brassicas is an unique set of challenges. During the Bejo symposium ‘Headed Opportunities, Cabbage: breeding, cultivation & innovation’ Jan Hoogland, researcher at Bejo, delivered an illuminating presentation that delved into the intricacies of Brassica cultivation and the formidable hurdles it faces.

Jan Hoogland's work is centered at Bejo’s research center with a specialized focus on Brassicas, a family of plants known for their varied edible parts, including roots, stems, leaves and flowers. This diversity is both a blessing and a curse, as each part is susceptible to different diseases and pests, making Brassica crops particularly vulnerable.

Five specialized departments
To tackle these challenges, Jan highlighted the significance of five specialized departments within the research center: Phytopathology & Content matter, Tissue culture & cell biology, Marker technology & Genomics, Seed pathology, and Seed Physiology. Each of these departments play a crucial role in supporting breeding efforts and understanding the complexities of Brassica cultivation.

Classifying Brassica diseases: biotic and abiotic challenges
One of the themes of the presentation was the classification of diseases affecting Brassicas. The challenges were divided into two categories: biotic and abiotic diseases. Biotic adversaries include fungi, oomycetes, viruses, bacteria and nematodes. Each of these pathogens can damage Brassica crops, requiring distinct management strategies. The Cropalyser app is a valuable source for in-depth disease descriptions.

The importance of distinguishing between primary and secondary infections when dealing with these pathogens was stressed, a crucial factor in crafting effective disease management plans. Abiotic factors, such as nitrogen excess and nutrient deficiencies, were also discussed for their impact on Brassica health.

The complexity of Brassica diseases extends beyond the diversity of pathogens to the different plant parts they affect. He explained how pathogens can target roots, stems, leaves, or even flowers, resulting in distinct diseases with varying symptoms and management challenges.

Xanthomonas on Brassicas
A major focus was the bacterial disease known as Xanthomonas on brassicas. This disease, characterized by V-shaped lesions on mature crops, poses a substantial threat to the industry. detailed the transmission modes of Xanthomonas, which include mechanical means, water droplets, and even insects. Disease-free seeds and stringent hygiene practices emerged as essential tools in its management.

The battle against clubroot
An other challenge in Brassica cultivation is clubroot. Caused by a protist, this disease primarily affects the plant roots, causing malformation and stunted growth. The role of varietal differences in susceptibility to clubroot and the importance of hygiene practices to curb its spread was emphasized.

Effective strategies for disease management
In conclusion, the presentation unveiled the multifaceted challenges faced by brassica cultivators, from diverse diseases to the complexities of managing specific pathogens like Xanthomonas and clubroot. His insights emphasized the need for ongoing research, collaboration, and innovation within the industry to develop effective strategies for disease management and crop improvement in the world of brassicas.