RNA interference (RNAi)-based host-induced gene silencing (HIGS) is one of
the new tools used in fighting phytonematode infection in crop plants.
Mi-msp-1, an effector gene expressed in the subventral pharyngeal gland
cells of root-knot nematode (Meloidogyne incognita) has a vital function in
the parasitic process.
Scientists from Indian Agricultural Research Institute and other
institutions generated six eggplant transformants with a single copy RNAi
transgene of Mi-msp-1. The transgene was expressed in T1, T2 and T3
transgenic lines for which a detrimental effect on root-knot nematodes
penetration, development and reproduction was documented upon challenge
infection with nematode juveniles. Furthermore, the post-parasitic nematode
stages derived from the transgenic plants exhibited long-term RNAi effect as
manifested in the targeted downregulation of Mi-msp-1.
The results of the study imply that HIGS of Mi-msp-1 improved resistance to
nematode in eggplant and protect the plant against RKN parasitism at the
very early stage.