b'against Aphanomyces rootRNA is a fundamentalI think the biggest rot. Over the past decade,molecule present in all livingproblem with root rot is that root rot has become the toporganisms. It plays a crucialits not just one organism production challenge forrole in translating geneticwere dealing with; its a mix Saskatchewan pea and lentilinformation into proteins,of several pathogens. Most growers, according to thewhich are the building blockspeople have probably heard of Saskatchewan Pulse Growersfor enzymes, structures, andAphanomyces euteiches, which (SPG). various other componentsis, in many ways, the most It thrives in wet, warmessential for life. problematic one. We know the conditions and has expandedIn the context of plantleast about it, and there are across the province, causingpathogens, lets visualize areally no effective chemistries up to 6084% yield declinesscenario: on the left, we have aagainst it, she adds. in peas and lentils with lossesseed, and on the right, a spore.Aphanomyces can survive in sales and exports of up toWhen a spore germinates, itin the soil for long periods, $1.5 billion a year, SPG says. produces a germ tube thatwhich is why theres a recom- Tyler Wist is an entomologist with Agriculture and Agri-Food Currently, a few specificmakes contact with the seed.mendation for six, eight, orCanada.practices or products canIf the seed lacks resistanceeven 10-year rotations with-manage Aphanomyces, oneor hasnt been treated, theout pea and lentil.of the most harmful patho- pathogen can infect the seed,But its not just gens in the root rot complexshe says. Aphanomyces. Theres also affecting pulses. The primaryTraditionally, we protecta whole catalog of different strategy for controlling itplants by breeding resistanceFusarium species, she notes. involves long-term crop rota- into seeds or applying seedIf youre primarily a tions, avoiding peas or lentilstreatments and fungicides.cereal grower, you might for six to eight years or more.This is akin to defendingrecognize some of the names Thats a long time to totallyagainst an invasion where thebecause these pathogens can stop growing a specific crop,pathogen, like an enemy, usesinfect both pulse and cereal she notes. weapons produced in its fac- roots, making the situation A project shes spearhead- tories to bombard the plant.even trickier.ing at the CDC recentlyRNA interference (RNAi) received more than $4.2offers a different strategy.Staying Ahead of the Enemy Sabine Banniza is a pulse million from the StrategicThink of RNAi asTrying to outsmart cleverpathologist at the University Research Initiative (SRI) todisrupting the machinerypests and pathogens is a hardof Saskatchewans Crop discover and develop solutionsin the pathogens factories,game to play, especially whenDevelopment Centre.for root rot in pea and lentilpreventing it from produc- said pathogen is as stealthy crops. Its a project that coulding these weapons. Withoutas soybean cyst nematode lead to Canada being a worldits weapons, the pathogen(SCN). The nematodeleader in how to develop pulsecannot invade and infect theliterally a kind of animalvarieties resistant to root rot. plant. This method targets thepenetrates the root system and Her team will investigatepathogens ability to harm thecauses yield reduction. The biocontrol and other marketplant at a molecular level. nematode overwinters as eggs, products to see if combiningIn practice, RNAi mighthatches, and infects the roots. them with the first generationbe applied through seedLike other plant-parasitic of varieties with improvedtreatments or soil drenchingnematodes, it goes through resistance can provide short- rather than sprays, especiallyfour different stages before term solutions for farmers,for root rot pathogens. Thebecoming an adult. but theyre also delving intospecificity of RNAi is itsIt releases effectors into the genome to find a newstrength, allowing targetedplants to modify cells and approach to protecting cropsaction against pathogens.take control of the plants using RNAi fungicides. ThisHowever, this specificity alsomachinery. It modifies cellsHoracio Lopez-Nicora is a innovative method could offermeans that different RNAito feed the now-sedentaryplant pathologist at Ohio State a novel way to enhance cropapproaches are needed for dif- nematode, which cant moveUniversity.protection. ferent pathogens. anymore, and continues SEPTEMBER 2024 SEEDWORLD.COM/CANADA 43'