John Halbrendt, Ph.D.

Areas of Interest

Research/extension; plant parasitic nematodes and nematode-transmitted virus diseases of fruit; development of ecologically sound and sustainable nematode management practices; biology and ecology of plant parasitic nematodes

Program Interests

Fruit trees may grow poorly, fail to establish, or have a shortened productive life on replant sites. These problems result from factors that developed over decades of continuous production, including populations of plant-parasitic nematodes. Soil fumigation has been the single most effective tool for combating these replant problems. However, fumigants have been identified as a potential threat to public health and groundwater contamination. The fruit industry needs safe, environmentally sound alternatives to control nematodes and nematode-transmitted viruses. Several lines of research are being investigated, including the exploitation of naturally occurring nematicidal compounds, genetic resistance, and improved orchard management techniques. The primary goal of this program is to develop effective nematode management strategies that rely more on cultural practices and biological solutions and less on the application of synthetic pesticides.

Many plants reportedly produce natural nematicidal compounds, and these offer the potential of developing novel short-term rotations to suppress nematode populations on replant sites. Some novel soil treatments may provide additional benefits by increasing populations of free-living nematodes that have a role in nutrient recycling or by suppressing noxious weeds. Understanding nematode/host relationships, chemical and physical changes in soil resulting from plant decomposition, and how plant roots and their exudates modify the soil ecosystem may lead to crop rotations in farming practices that control nematodes in an economically viable and ecologically sound manner.

Another line of research includes screening exotic fruit tree germplasm for genetic resistance to nematode feeding or nematode-transmitted virus. Development of fruit tree rootstocks with genetic resistance to nematode-induced disease would provide the most economical and sustainable solution to replant problems.

Publications

Nyzcepir, A. P. and J. M. Halbrendt. 1993. "Nematode parasites of fruit trees." pp. 381-425 In: K. Evans, D. Trudgill, and J. Webster (eds.). Plant Parasitic Nematodes in Temperate Agriculture. C. A. B. International, Wallingford, UK.

Brown, D. J. F., J. M. Halbrendt, A. T. Jones, C. E. Taylor, and F. Lamberti. 1994. "An appraisal of some aspects of the ecology of nematode vectors of plant viruses." Nematologia Mediterranea 22:253-263.

Brown, D. J. F., J. M. Halbrendt, A. T. Jones, T. C. Vrain, and R. T. Robbins. 1994. "Transmission of three North American nepoviruses by populations of four distinct species of the Xiphinema americanum group." Phytopathology 84:646-649.

Halbrendt, J. M. and D. J. F. Brown. 1994. "Inter- and intraspecific variation in wild-type and single female derived populations of Xiphinema americanum-group nematodes." Journal of Nematology 26:212-221.

Halbrendt, J. M. and G. Jing. 1994. "Nematode suppressive rotation crops for orchard renovation." Acta Horticulturae 363:49-56.

Halbrendt, J. M., E. V. Podleckis, A. Hadidi, R. Scorza, and R. Welliver. 1994. "A rapid protocol for evaluating Prunus germplasm for tomato ringspot virus resistance." HortScience 29:1068-1070.

Jing, G. N. and J. M. Halbrendt. 1994. "Nematicidal compounds from rapeseed (Brassica napus and B. campestris)." Journal of the Pennsylvania Academy of Science 68:29-33.

Faghihi, J., R. A. Vierling, J. M. Halbrendt, V. R. Ferris, and J. M. Ferris. 1995. "Resistance genes in a 'Williams 82' x 'Hartwig' soybean cross to an inbred line of Heterodera glycines." Journal of Nematology 27:418-421.

Jones, A. T., D. J. F. Brown, J. M. Halbrendt, T. C. Vrain, and R. T. Robbins. 1995. "The transmission of three nepoviruses by populations of four Xiphinema americanum-group species." Acta Horticulturae 385:105-109.

Robbins, R. T., D. J. F. Brown, J. M. Halbrendt, and T. C. Vrain. 1995. "Compendium of Longidorus juvenile stages with observations on L. pisi, L. taniwha, and L. diadecturus (Nematoda: Longidoridae)." Systematic Parasitology 32:33-52.

Halbrendt, J. M. 1996. "Allelopathy in the management of plant-parasitic nematodes." Journal of Nematology 28:8-14.

Halbrendt, J. M. and G. N. Jing. 1996. "Cruciferous green manure as an alternative to nematicide: the effect of glucosinolate content." pp. 458-465 In: Proc. Third International Conference on New Industrial Crops and Products - 1994. L. H. Princen and C. Rossi (eds.). The Association for the Advancement of Industrial Crops, Catamarca, Argentina.

Robbins, R. T., D. J. F. Brown, J. M. Halbrendt, and T. C. Vrain. 1996. "Compendium of juvenile stages of Xiphinema species (Nematoda: Longidoridae)." Russian Journal of Nematology 4:163-171.

Brown, D. J. F. and J. M. Halbrendt. 1997. "Identification of Xiphinema species (Nematoda: Dorylaimoidea)." In: An Introduction to Virus Vector Nematodes and Their Associated Viruses. M. S. N. d. A. Santos, I. M. d. O. Abrantes, D. J. F. Brown, and R. M. Lemos (eds.). Grafica de Coimbra Lda., Coimbra, Portugal.