Screening Wild Brassica Species Against Alternaria Brassicicola (Schw.) Wiltsh for Breeding Alternaria Leaf Spot Resistance in Brassica Vegetables

Abstract

Abstract Alternaria leaf spot (ALS) is a major disease of Brassica crops, and it causes huge economic losses to both the cultivated oilseed-and vegetable- Brassicas . The present study was aimed to develop a non-destructive robust method for screening of wild Brassica species and to find resistant wild species against Alternaria brassicicola (Schw.) Wiltsh available in the germplasm. For this, 38 wild Brassica species were screened at adult plant stage by an in vitro detached leaf inoculation method in three consecutive years i.e. 2019-20, 2020-21 and 2021-22. The new screening protocol provides favourable environment (temperature 25±2 °C; relative humidity >90%) for the pathogen and retained the host leaves in condition (by placing sucrose 5% w/v in petiolar base) for disease development. The consistency in reactions of the species against A. brassicicola during all three years of testing indicates the robustness of the protocol. Further, the multiple parameters were recorded on leaf condition and disease response of the wild species. Complete resistance was observed in Capsella while resistance in Lepidium , Camelina and Biscutella . Both Capsella bursa pastoris (L.) Medik (early) and C. bursa pastoris (late) were symptomless resistant. Camelina sativa (L.) Crantz, Diplotaxis erucoides (L.) DC and Diplotaxis gomez-campoi Mart.-Laborde were found to be resistant against A. brassicicola . The significant correlation between disease parameters indicates the robustness and effectiveness of the screening protocol for wild Brassica species.

Plant phenotyping relevance

野生Brassicaの病害抵抗性という植物状態を測定する非破壊的な葉接種スクリーニング法を開発し、複数年で頑健性・有効性を検証しているため、方法が中心的である。

Code and data availability

The paper describes detached-leaf screening of wild Brassica species against Alternaria brassicicola, but no public phenotype dataset, image/sensor data, author analysis code, or trained model is deposited. NCBI is used only for BLAST of ITS sequences (molecular, not phenotyping data), MEGA and OPSTAT are generic third

No evidence-backed public reproduction asset is currently recorded.