The Department of Nematology's weekly NEMA 250 seminar series is presented this week by:

Francisco Franco-Navarro, M.Sc., Ph.D. Candidate, PLPA Graduate Program, Department of Nematology, UC Riverside

Seminar Title: “Root-Knot Nematodes and Bell Pepper Pathosystem: Impact and Some Strategies for its Management"

Brief Biography: Francisco obtained his BSc degree in Biology from National Autonomous University of Mexico, and his MSc degree in Plant Pathology from Graduate College in Agricultural Sciences, studying topics about plant-parasitic nematodes like Biology, Parasitism and Management. He is a PhD candidate and a member of the Antoon Ploeg’s Lab (Nematology Extension and Research Lab). His research focuses on the impact and some strategies for the control of root-knot nematodes (Meloidogyne) on bell pepper, mainly genetic resistance and the alternative use of new nematicides.

Seminar Summary: Meloidogyne incognita, also known as the Southern Root-Knot Nematode (SRKN), is a serious pest in many regions in the south of US on many solanaceous crops including pepper, tomato and eggplant; this species is the major constraint to pepper production, mainly bell pepper in US and throughout the world. In addition to this real and present pathogen in pepper, there is another potential threat for this vegetable crop which must be studied due to its high pathogenicity and close relation with M. incognita, the Peach Root-Knot Nematode (PRKN), Meloidogyne floridensis.
In general, very few data about how peppers yield is significantly affected by root-knot nematodes (RKNs) for common California pepper cultivars are available. On the other hand, RKNs have been usually managed on peppers in US by pre-plant treatment of soil with fumigant nematicides;
however, the use of fumigants is becoming more restricted, due to their adverse effects on the environment and general human health. One of the alternatives for controling RKNs is the use of new non-fumigant nematicides like fluensulfone, which belongs to the heterocyclic fluoroalkenyl sulfones, a new class of chemicals used to control RKNs in several crops including peppers. The standard way to apply this nematicide is a pre-plant soil incorporation, but there are a few reports about the effects of this chemical when is applied on the foliage of pepper; nothing is known about the effectivity of a foliar spray of fluensulfone on other important vegetables crops or on different pepper varieties. In addition to the chemical control of RKNs, the genetic control of these pathogens is another reliable option by means of the use of resistant germplasm or those rootstocks with nematode-resistance and graft compatibility. It is known about the resistance in some lines and cultivars of Capsicum to several different Meloidogyne species, and some genes have been identified; for grafted pepper plants, these are not commonly used at present in field-grown pepper production, but the restricted availability of fumigant nematicides and increased interest in organic farming methods provides opportunities for the use of grafting as a method to manage soilborne diseases, including RKNs.