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  • Johnny Bek posted an update 7 years, 5 months ago

    Twelve Cucurbita maxima x C. SYN115 manufacturer moschata commercial squash hybrid rootstocks had GI ranging from 4.two for `Carnivor’ to five.0 for Jing Xin No.three. The common Cucurbita maxima x C. moschata hybrid `Strong Tosa’ also was very susceptible with GI=4.9. Field test, Charleston, SC. melo) was grafted on eight distinct cucurbit rootstocks and evaluated inside a field that was very infested with M. incognita. Rootstocks of Benincasa hispida, Cucurbita maxima x C. moschata, Cucurbita argyrosperma, C. melo, C. maxima, and Cucurbita ficifolia were all very susceptible to RKN with numbers of M. incognita eggs per gram fresh root ranging from 659 for B. hispida to six,793 for C. argyrosperma. Cucumis metulifer exhibited moderate resistance and supported 323 eggs per gram fresh root. As a result, C. metulifer was the only cucurbit rootstock evaluated in our tests that exhibited resistance to M. incognita. At present, we’re evaluating all the C. metulifer PIs in the USDA Plant Introduction collection in an effort to identify the most resistant and vigorous accessions for use in establishing RKN-resistant rootstocks for melon. USE OF PROPAGATED PLANT CUTTINGS TO ACCELERATE SCREENING CAYENNE PEPPER FOR RESISTANCE TO MELOIDOGYNE INCOGNITA. Thomas, Stephen1, J.M. Beacham1, and P.W. Bosland2. 1Department of Entomology, Plant Pathology and Weed Science, P.O. Box 30003 MSC 3BE; and two Division of Plant and Environmental Sciences, P.O. Box 30003, MSC 3Q, New Mexico State University, Las Cruces, NM 88003. Working with sodium hypochlorite to assess egg production per unit of root weight in young plants would be the most sensitive, speedy, and quantitative approach for screening breeding lines for resistance to southern root-knot nematode (Meloidogyne incognita). On the other hand, a limitation to this strategy is that it destroys those very plants identified as desirable for further investigation. In 2009, a greenhouse study was performed to assess and boost resistance to M. incognita in three NMSU cayenne chile (Capsicum annuum) cultivars, `NuMex Nematador’ (96 plants) and two accessions of `NuMex Las Cruces’ (79 78 plants every single). Individual plants from each and every cultivar and in the common resistant handle `Carolina Cayenne’ had been inoculated with two,500 M. incognita eggs per plant and evaluated 42 days later. Before bleach extraction of roots, cuttings were propagated from each plant. No eggs (zero nematode reproduction) were recovered from two of 96 Nematador plants, and 1-5 eggs were recovered from four of 157 `NuMex Las Cruces’ plants. Seeds from the two Nematador plants have been collected separately and 24 progeny of every single were tested in an extra greenhouse study in 2010, where some M. incognita reproduction was observed. In 2011, in spite of the outcomes from previous years, both Nematador lines were transplanted into 90-cm diameter field microplots, along with cayenne cultivars `Mesilla’ (RKN-susceptible), `Large Red Thick’ (Nematador parent), and `Carolina Cayenne'(resistant manage). Half the plots had been pre-infested with M. incognita. Plants have been fertilized and irrigated as required throughout the season. Pod count, total pod weight, and RKN eggs/g dry root have been recorded at harvest. One particular Nematador isolate showed the least RKN reproduction (four,533 eggs/g dry root) compared to susceptible Mesilla (78,689 eggs/ g dry root).