THE HISTORY AND ACHIEVEMENTS OF THE NEMATOLOGY SECTION, 1955-2002
Florida Department of Agriculture
by
R. P. ESSER and P. S LEHMAN

ORIGINS

Informal phase
Seventy-eight years ago, on February 21, 1917, Plant Inspectors Luther Brown and Dillard Grimes detected cyst nematodes in a shipment of figs going from Argyle, Florida to Pensacola. This nematode detection was possibly the first of its kind by a regulatory organization in Florida, and plant inspectors have been on guard against these pests ever since. From 1919 to 1954, plant inspectors submitted 1,102 samples for nematode detection. In this early period, bulb and stem, cyst, foliar, root-knot and lesion nematodes were the chief nematode pests targeted by the inspectors.

Formal Phase
        Dr. Benjamin G. Chitwood, one of the world's most eminent nematologists, joined the State Plant Board in February 1955. Dr. Chitwood established a Department of Nematology and served as its first chief. Dr. Chitwood initiated methodology, systems, and procedures essential to the operation of a proper nematological installation, many of which survive today. He also completely equipped the new Department, and taught the fundamentals of Nematology to Dr. Chancellor I. Hannon, who was employed in May 1955, to Robert P. Esser, who transferred from Plant Inspection to the Department of Nematology in July 1955, and to Dr. Leon G. van Weerdt who was employed in February 1956. Dr. Wray Birchfield joined the State Plant Board in June 1954, and came under the jurisdiction of the Department of Nematology in 1955. Dr. Birchfield conducted principally burrowing nematode research at Winter Haven, Florida. He also supervised the burrowing nematode identification laboratory in Lake Alfred. Dr. Dewey Raski, on sabbatical leave from the University of California, was employed by the State Plant Board in October 1955 and worked for six months on burrowing nematode control.
        Dr. Chitwood resigned in January 1958 and Dr. Birchfield in June 1959. Fred Donaldson joined the Nematology Department in 1959 and served as a nematologist until 1966. Dr. van Weerdt was appointed chief and served until 1960, at which time he resigned to enter law school. R. P. Esser was in charge of the Nematology Department and then Nematology Section from 1960 through 1968. In January 1961 the Florida Department of Agriculture absorbed the duties and staff of the State Plant Board. In the reorganization, the Department of Nematology became the Nematology Section. John B. MacGowan joined the Department of Plant Inspection in July 1960. He was placed in charge of a mobile Nematology Laboratory in Apopka, Florida. The objective of this unit was to survey and process nursery samples for reniform nematode. He became a member of the Nematology Section in 1964.
        Donald E. Stokes transferred from Plant Inspection to the Nematology Section in February 1966. Dr. Kenneth R. Langdon assumed the position of Botanist, in addition to his regular duties as a nematologist. Dr. Langdon was Nematologist-In-Charge from 1968 to 1972. In 1969 the Nematology Section became the Bureau of Nematology. In November 1972, the position of chief, vacant since 1960, was filled with the appointment of Alfred L. Taylor, formerly in charge of the Nematology Investigations within the Agricultural Research Service of the United States Department of Agriculture. A. L Taylor served as chief until December 1975. Dr. D. E. Stokes was appointed Chief Nematologist in January 1976 and served until his retirement in October 1982. During Dr. Stokes tenure, Dr. James G. Baldwin (June 1976 until June 1978) and Dr. Paul S. Lehman (August 1978 to present) joined the staff. Dr. R. P. Esser served as nematologist-in-charge from November 1982 until July 1984, when Dr. John H. O'Bannon assumed the duties of chief. Dr. Renato N. Inserra joined the Bureau in 1985. Following Dr. O'Bannon's resignation in September 1991, Connie Riherd (Assistant Director) assumed the duties of acting chief until December1992 when the three technical bureaus were amalgamated into the Bureau of Entomology, Nematology, and Plant Pathology, and designated as individual sections within the Bureau. At that time, Dr. Wayne N. Dixon was appointed Chief, Bureau of Entomology, Nematology, and Plant Pathology and he has served also as Biological Administrator for the Nematology Section since that time. Dr. R. P Esser retired in 1999 and was replaced by Dr. Claudia Riegel in January 2000. She resigned a few months later to accept a position with industry and Dr. Janete A. Brito joined the Nematology Section in October 2000.

SUMMARY OF THE NEMATOLOGY SECTION’S PROGRAMS AND ACTIVITIES

        Current activities of this section are analyses of soil and plant samples for nematodes, identification of plant parasitic nematodes involved in regulatory and certification programs, pest detection surveys, and diagnosis of plant problems. State of Florida Statutes and regulatory rules applicable to nematode pests mandate the principal part of the regulatory activity of the Section. Nematological analyses include those from in-state programs, out-of-state and out-of-country plant shipments originating in Florida, and shipments intercepted in Florida from outside the United States. Other functions focus on surveys to detect exotic nematode pests, describing new nematode species, maintenance of taxonomic data retrieval systems, nursery sanitation programs, host testing, biological control investigations, and molecular diagnostic research.

BENEFITS FROM THE NEMATOLOGY SECTION’S PROGRAMS

        The Nematology Section was established in the mid-1950s because the burrowing nematode began causing serious decline of citrus in Central Florida. The Florida Department of Agriculture, in cooperation with citrus growers, launched regulatory programs to prevent the spread of this serious nematode pest of citrus. Also at this time a parallel program to tract the burrowing nematode of Citrus was established by the United States Department of Agriculture in Winter Haven, Florida. Later this Program was turned over to the Florida Department of Agriculture and Consumer Services, with S. Simpson and J. Ward in charge of nematode sample analyses in the Winter Haven laboratory until the Nematology Section in Gainesville assumed this responsibility in 1984.A very conservative estimate is that these regulatory programs prevented the spread of the burrowing nematode into 44,000 acres or 18,000 hectares. The benefits of these burrowing nematode regulatory programs for Florida’s citrus growers from 1960 to1994 are calculated to be 1.4 billion dollars. The regulatory management costs were only about 7% of the benefits to the growers, or for every $70,000 invested in the programs there was a return of $1million.

Citrus nursery certification programs insure that seedlings produced in citrus nurseries are free of burrowing nematodes and other nematode pests. For the past 35 years these programs have been very effective in preventing the spread of nematode pests into Florida's citrus groves. Because citrus is a perennial crop which may be productive for 25 to 40 years, growers benefit for many years from planting certified seedlings. For the 2000 crop season alone, the benefit to growers from excluding nematodes from their groves through planting certified nematode-free seedlings was calculated to be 50 million dollars in on-tree value of fruit. Total annual costs to the Plant Inspection and Nematology section for nematode certification programs for citrus nurseries was $75,000 in 2000. Thus, in 2000 for every dollar invested in the administration of the nematode certification program in Florida, there was a return of approximately $666 to growers.

Florida's ornamental industry also greatly benefits from the activities of the Nematology Section. Nematode certification programs for ornamental plants allow the ornamental industry of Florida to export plants to markets located in other states and countries that impose restrictions against nematode pests occurring in Florida. Without these certification programs many export markets would be closed to Florida's billion-dollar ornamental industry.

In addition, the Nematology Section's programs benefit the general public. Sanitation and certification programs that exclude nematodes lower pesticide use, thus impacting favorably on the environment. These programs prevent the spread of nematodes that damage crops, lower production costs for growers and, in the end, result in lower food costs. It is also recognized that a strong vibrant economy in Florida is linked to the agricultural industry, especially healthy citrus and ornamental sectors.

The Nematology Section has been the major contributor to our knowledge of nematode distribution and biodiversity in Florida. Since 1955, the Nematology Section has analyzed over 600,000 nematode samples.At least 372 plant parasitic nematode species have been reported in Florida based on DPI records and original taxonomic descriptions of nematodes from Florida. One subfamily, three genera and 20 species have been originally described in the Nematology Section.
 

Taxon                                     Authors and year

Haliplectus bickneri  Chitwood, 1956
Meloidodera floridensis  Chitwood, Hannon & Esser, 1956
Criconema decalineatum  Chitwood, 1957
Criconema spinalineatum   Chitwood, 1957
Xiphinemella esseri  Chitwood, 1957
Hemicriconemoides biformis  Chitwood & Birchfield, 1957
Hemicriconemoides floridensis  Chitwood & Birchfield, 1957
Hemicriconemoides wessoni   Chitwood & Birchfield, 1957
Hemicriconemoides chitwoodi  Esser, 1960
Hemicriconemoides minutus  Esser, 1960
Hemicriconemoides strictathecatus     Esser, 1960
Sphaeronema whittoni  Sledge & Christie, 1962
Hypsoperine graminis Sledge & Golden, 1964
Xiphinema macrostylum Esser, 1981
Verutinae                                             Esser, 1981
Verutus volvingentis  Esser, 1981
Meloidogyne cruciani  Garcia-Martinez, Taylor & Smart, 1982
Tylenchulus graminis  Inserra, Vovlas, O'Bannon & Esser, 1988
Tylenchulus palustris  Inserra, Vovlas, O'Bannon & Esser, 1988
Mesocriconema ornicauda  Vovlas, Inserra & Esser, 1991
Ogma floridense  Vovlas, Inserra & Esser, 1991

Updated JANUARY 2011

This document was constructed and is maintained by KHUONG B. NGUYEN
Entomology and Nematology Department
University of Florida