J. Creighton Miller Jr. and Douglas C. Scheuring
Philip D. Dukes Sr. and Richard L. Fery
Susan L.F. Meyer, Dilip K. Lakshman, Inga A. Zasada, Bryan T. Vinyard, and David J. Chitwood
the root-knot nematode Meloidogyne incognita Pest Mgt. Sci. 64 223 229 Montes-Belmont, R. Carvajal, M. 1998 Control of Aspergillus flavus in maize with plant essential oils and their components J. Food Prot. 61 616 619 Pandey, R.C. Dwivedi, B
Rachel E. Rudolph, Carl Sams, Robert Steiner, Stephen H. Thomas, Stephanie Walker, and Mark E. Uchanski
crops should also be a non-host for nematodes or able to suppress nematode populations in the field. Southern RKN ( Meloidogyne incognita ), a plant–parasitic nematode, is of great concern to chile pepper growers in southern New Mexico ( Walker et al
Tanner Donahoo, Lisha Zhang, Matthew Cutulle, and Abolfazl Hajihassani
because increased levels of resistance to root-knot nematode ( Meloidogyne incognita ) have been reported for these two cultivars ( Hajihassani et al., 2020 ). ‘Maxifort’ was selected as a rootstock because it has been reported to reduce the incidence of
Judy A. Thies and Richard L. Fery
Two isogenic sets of bell pepper (Capsicum annuum L.) lines (differing at the N root-knot nematode resistance locus) were characterized for resistance to Meloidogyne arenaria (Neal) Chitwood races 1 and 2, M. hapla Chitwood, and M. javanica (Treub) Chitwood in greenhouse and growth chamber tests. The isogenic sets of C. annuum were `Charleston Belle' (NN) and `Keystone Resistant Giant' (nn-recurrent parent), and `Carolina Wonder' (NN) and `Yolo Wonder B' (nn-recurrent parent). Meloidogyne arenaria race 1 is pathogenic to C. annuum. `Charleston Belle' and `Carolina Wonder' exhibited high resistance to M. arenaria race 1. Their respective recurrent backcross parents, `Keystone Resistant Giant' and `Yolo Wonder B', were susceptible to M. arenaria. Meloidogyne arenaria race 2 and M. javanica are not highly pathogenic to pepper. However, `Charleston Belle' and `Carolina Wonder' both exhibited higher (P≤0.05) resistance to M. arenaria race 2 and M. javanica than `Keystone Resistant Giant' and `Yolo Wonder B'. Meloidogyne hapla is pathogenic to pepper. Both `Charleston Belle' and `Carolina Wonder' and their respective recurrent parents, `Keystone Resistant Giant' and `Yolo Wonder B', were susceptible to M. hapla. We concluded that the N gene confers resistance to M. arenaria races 1 and 2, and M. javanica in C. annuum, but the N gene does not condition resistance to M. hapla.
J.C. Cervantes-Flores, G.C. Yencho, and E.L. Davis
Five sweetpotato [Ipomoea batatas (L.) Lam.] cultivars (`Beauregard', `Excel', `Jewel', `Hernandez', and `Porto Rico') were evaluated for resistance to three root-knot nematode species: Meloidogyne arenaria (Neal) Chitwood (race 2), M. incognita (Kofoid & White) Chitwood (race 3), and M. javanica (Treub) Chitwood. Resistance screening efficiency was assessed in both 400-cm3 square pots and 150-cm3 Conetainers™. Nematode infection was assessed as the percentage of root system galled, percentage of root system necrosis, and the number of nematode eggs produced per gram of root tissue. Means of these dependent variables were not different (P ≤ 0.05) between container types, with Conetainers™ being more efficient to use. Root necrosis was not related to nematode infection, but was significant among cultivars (P = 0.0005). The resistance responses of the cultivars differed depending on the nematode species. All five cultivars were resistant to M. arenaria race 2. `Hernandez', `Excel', and `Jewel' were also resistant to M. incognita race 3 and M. javanica.
H.Y. Hanna, P.D. Colyer, T.L. Kirkpatrick, D.J. Romaine, and P.R. Vernon
Studies were conducted for 2 years in root-knot-nematode-infested soils to determine growth and yield response of `Dasher II' cucumbers (Cucumis sativus L.) to double-cropping with nematode-resistant tomatoes (Lycopersicon esculentum Mill.), using nematode-free cucumber transplants and preplant treatment with ethoprop nematicide. Cucumbers grown following the nematode-resistant `Celebrity' tomato during the same season produced significantly more plant dry weight, more fruit per plant, and higher premium and total yields than did cucumbers double-cropped with the nematode-susceptible `Heatwave' tomato in both years. The cucumber produced longer stems in 1992 and fewer culls in 1993 following resistant tomatoes. Cucumber plants raised in nematode-free soilless mix for 3 weeks before transplanting produced significantly longer stems and more plant dry weight than did direct-seeded cucumbers in 1992, but not in 1993; however, they produced significantly higher premium yield in both years, and higher total yield, more fruit per plant, and fewer culls in 1993. Preplant treatment with ethoprop significantly increased cucumber stem length, dry weight, premium and total yield, and number of fruit per plant in 1992 but not in 1993. Ethoprop treatment had no effect on the percentage of culls in either year. Chemical name used: O-ethyl S,S-dipropyl phosphorodithioate (ethoprop).
Martin Schochow, Steven A. Tjosvold, and Antoon T. Ploeg
Lisianthus [Eustoma grandiflorum (Raf.) Shinn.] plants were grown in soil infested with increasing densities of Meloidogyne hapla Chitwood, M. incognita (Kofoid & White) Chitwood, or M. javanica (Treub) Chitwood, root-knot nematodes. Compared to tomato plants grown in soil with the same nematode numbers and species, lisianthus had less severe root symptoms, suffered less damage, and resulted in lower nematode multiplication rates. Lisianthus was a better host for M. javanica than for M. incognita, and a poor host for M. hapla. Lisianthus shoot weights were significantly reduced after inoculation with M. javanica or M. hapla, but not after M. incognita inoculation. The number of flowers produced per lisianthus plant was reduced by all three nematode species. The results show that the root-knot nematode species that are most common in California may cause significant damage in the cut-flower production of lisianthus.
S.D. Nelson, S.J. Locascio, L.H. Allen Jr., D.W. Dickson, and D.J. Mitchell
Methyl bromide (MeBr) is an important and effective soil fumigant commonly used to control weeds and soilborne pests. Because MeBr has been implicated as a contributor to the depletion of stratospheric ozone, it is scheduled for phaseout by 2005. This study examined nonchemical and chemical practices as alternatives to MeBr. Off-season flooding followed by a series of soil preplant chemical treatments [MeBr with 33% Pic; 1,3-D mixed with 17% (C-17) and 35% (C-35) Pic combined with Peb; and metam-Na combined with 1,3-D and Peb were evaluated on spring tomato (Lycopersicon esculentum Mill.) and eggplant (Solanum melongena) production in northern Florida. Pest control and tomato and eggplant yields were not significantly different between the flooded and non-flooded control plots. The most effective alternatives to MeBr were 1,3-D and Pic mixtures (C-17 and C-35) combined with Peb. Tomato and eggplant yields for these chemicals were statistically equivalent to that of MeBr. Tomato, but not eggplant, yield and nematode control were poor with metam-Na combined with 1,3-D and Peb in comparison to the other fumigant combinations. Chemical names used: 1,3-dichloropropene (1,3-D); trichloronitromethane [chloropicrin (Pic)]; S-propyl butyl(ethyl)thiocarbamate [pebulate (Peb)]; sodium N-methyldithiocarbamate (metam-sodium (metam-Na)].