Chromosomal assignment of oil radish resistance to Meloidogyne incognita and M. javanica using a set of disomic rapeseed-radish chromosome addition lines

Abstract

Root-knot nematodes cause severe damage to a great number of crops worldwide. The use of nematicides is restricted due to environmental and toxicological risks and control of the pest by crop rotation is difficult because root-knot nematodes have a very wide range of host plants. To verify the strategy of converting rapeseed from a tolerant host for Meloidogyne incognita and M. javanica to a resistant catch crop, a complete set of nine disomic rapeseed-radish chromosome addition lines (lines A to I) was tested for resistance against these Meloidogyne species. Thirty plants of each addition line and the rapeseed and radish parents as control were infected with 2500 second-stage juveniles per plant. The presence of the alien radish chromosome was confirmed by chromosome-specific microsatellite markers. After cultivation of the inoculated plants for 10 weeks in a climatic chamber the root systems were washed. The egg masses were stained with Cochenille Red and counted. The radish parent A24 was found to be resistant to M. incognita (2.4 egg masses (g root)-1 ) and M. javanica (0.4 egg masses (g root)-1 ) compared to 53.3 and 33.1 egg masses (g root)-1 for the susceptible rapeseed parent cv. Madora. The radish chromosome e was shown to be the carrier of radish root-knot nematode resistance with an average number of <1 egg mass (g root)-1 for M. incognita and M. javanica. The disomic addition lines B, C, D, G, H and I and the parental radish line A107 were classified as highly susceptible, whereas the addition lines A and F showed significantly reduced susceptibility for M. incognita but not for M. javanica. To our knowledge this is the first study on resistance effects of individual radish chromosomes in a rapeseed background against these root-knot nematodes.

Construction of VIGS Vector of Root-knot Resistant WRKY64 Gene in Rapeseed Addition Line EE

“…WRKY transcription factor plays an important role in regulating plant growth and development and responding to various environmental stresses [23]. The functions of WRKY transcription factors in rapeseed were mainly studied by constructing overexpression vectors and CRISPR/Cas9 gene editing vectors.…”

“…Chen et al [24] overexpressed BnWRKY149 and BnWRKY217, Copyright © Shaosong Zhang MCDA.000804. 13(1).2023 which proved that BnWRKY149 and BnWRKY217 played an important role in the resistance to abiotic stress ABA [23]. Cui et al [25] found that the overexpression of phosphate BnaWSR1 (BnaWSR1ca) in rapeseed protoplasts triggered the production of Reactive Oxygen Species (ROS) and cell death, while its ectopic expression in Arabidopsis increased the levels of salicylic acid (SA) and ROS, thus accelerating leaf senescence.…”