Nematode neuropeptides as transgenic nematicides

Abstract

Plant parasitic nematodes (PPNs) seriously threaten global food security. Conventionally an integrated approach to PPN management has relied heavily on carbamate, organophosphate and fumigant nematicides which are now being withdrawn over environmental health and safety concerns. This progressive withdrawal has left a significant shortcoming in our ability to manage these economically important parasites, and highlights the need for novel and robust control methods. Nematodes can assimilate exogenous peptides through retrograde transport along the chemosensory amphid neurons. Peptides can accumulate within cells of the central nerve ring and can elicit physiological effects when released to interact with receptors on adjoining cells. We have profiled bioactive neuropeptides from the neuropeptide-like protein (NLP) family of PPNs as novel nematicides, and have identified numerous discrete NLPs that negatively impact chemosensation, host invasion and stylet thrusting of the root knot nematode Meloidogyne incognita and the potato cyst nematode Globodera pallida. Transgenic secretion of these peptides from the rhizobacterium, Bacillus subtilis, and the terrestrial microalgae Chlamydomonas reinhardtii reduce tomato infection levels by up to 90% when compared with controls. These data pave the way for the exploitation of nematode neuropeptides as a novel class of plant protective nematicide, using novel non-food transgenic delivery systems which could be deployed on farmer-preferred cultivars.

Volatile organic compounds from Paenibacillus polymyxa KM2501-1 control Meloidogyne incognita by multiple strategies

“…VOCs kill nematodes by mechanisms that can affect the nervous system 28 , surface coat, intestine 8 , pharynx, or other tissues. Vacuoles were observed in the intestine of M .…”

“…That PPNs locate their plant hosts by chemoreception was proposed over 90 years ago 23 , and has since been demonstrated in vitro by chemotaxis assays on agar-filled dishes 24 – 27 . It has been suggested that the use of some compounds like neuropeptides to control nematode behavior might be an efficient way to reduce the infection levels of PPNs 28 . We hypothesize that a similar approach based on VOCS with which PPNs have a stable chemotactic response might also serve as a novel nematicidal mechanism.…”

Simultaneous RNAi Knockdown of Three FMRFamide-Like Peptide Genes, Mi-flp1, Mi-flp12, and Mi-flp18 Provides Resistance to Root-Knot Nematode, Meloidogyne incognita

“…rostochiensis, G. pallida and M. incognita and M. graminicola (Atkinson et al, 1988;Maule et al, 2002;McVeigh et al, 2005;Kimber et al, 2007;Dalzell et al, 2010;Holden-Dye and Walker, 2011;Atkinson L. E. et al, 2013;Papolu et al, 2013;McCoy et al, 2014;Kumari et al, 2017;Warnock et al, 2017). So far, nineteen FLPs have been identified in the M. incognita and out of which six have been established to have transcriptional evidence (Abad et al, 2008) and host-delivered RNAi of Mi-flp14 and Mi-flp18 in N. tabacum provided excellent reduction in nematode parasitism and reproductive potential (Papolu et al, 2013).…”

Chemosensory system of plant parasitic nematodes

“…神经肽样蛋白(neuropeptide-like protein, NLP)代 表研究最少的神经肽分组, 根据Warnock等人 [90] [69,91] . PF-127已广泛应用于植物寄生线虫与 植物的互作关系研究 [92] .…”