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The Degree of Heterodera Infectivity of Soil and its Determination

Published online by Cambridge University Press:  18 November 2009

D. W. Fenwick
D. W. Fenwick
Affiliation:
Institute of Parasitology, St. Albans.
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Extract

(1) A technique for measuring the infectivity of soil with Heterodera schachtii in terms of the number of larvae potentially capable of infecting plants per pound of soil is described.

(2) The liberation of the larvae is accomplished by subjecting the cysts recovered from one half-pound sample of soil to a given strength of calcium hypochlorite solution for four hours. The loss of larvae due to solution during this time was found to be negligible.

(3) It was shown that if the larvae liberated were made up to a suspension, then counts made on 0·15 cc. samples of this suspension fall into a Poisson distribution and hence the accuracy of the final determination is dependent only on the number of larvae counted.

(4) It was found that provided the soil to be examined was thoroughly mixed that it was unnecessary to examine more than one half-pound sample as there was no significant difference between the means from different samples.

(5) Figures of cyst counts tabulated alongside available larvae show the utter inadequacy of cyst counts as a measure of infectivity.

(6) No attempt is made in this paper to determine how many of the larvae are alive and viable, further research into this matter being contemplated.

Type
Research Papers
Information
Journal of Helminthology , Volume 20 , Issue 1-2 , August 1942 , pp. 50 - 66
Copyright
Copyright © Cambridge University Press 1942

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References

Baunacke, W., 1922.—Untersuchungen zur Biologie und Bekämpfung des Rübennematoden (Heterodera schachtii, Schmidt).—Arb. biol. Reichsanst., XI, 185–288. (W.L. 1628.)Google Scholar
Boyd, A. E. W., 1941.—Determination of Death in the Larvae of the Potato Root Eelworm.—Nature Land., 148 (3765). 782–783. (W.L. 14900.)CrossRefGoogle Scholar
Fenwick, D. W., 1939.—Some Experiments on the Extra-Corporeal Hatching of the Eggs of Ascaris suum.—J. Helminth., XVII (2), 69–82. (W.L. 11224b.)CrossRefGoogle Scholar
Fenwick, D. W., 1940.—Methods for the Recovery and Counting of Cysts of Heterodera schachtii from Soil.—J. Helminth, XVIII (4), 155–172. (W.L. 11224b.)Google Scholar
Franklin, M. T., 1940.—On the Specific Status of the so-called Biological Strains of Heterodera schachtii, Schmidt.—J. Helminth., XVIII (4), 193–208. (W.L. 11224b.)CrossRefGoogle Scholar
Lapage, G., 1933.—Cultivation of Parasitic Nematodes.—Nature Lond., 131 (3312), 583–584. (W.L. 14900.)Google Scholar
Lapage, G., 1935.—The Second Ecdysis of Infective Nematode Larvae.—J. Parasitology, XXVII (2), 186–206. (W.L. 16035.)Google Scholar
Molz, E., 1930.—Über die Bekämpfung des Rübennematoden (Heterodera schachtii) mit reiz-physiologish wirkenden Stoffen.—Zbl. Bakt., Abt. 2, LXXXI. 92–103. (W.L. 23684.)Google Scholar
Molz, E., 1932.—Die Bekämpfung des Rübennematoden mittels des Chlorkalk-Aktivierungsverfahrens.—Dtsch. landw. Pr., LIX (30). 371–373. (W.L. 7262.)Google Scholar
Morgan, D. O., 1925.—Investigations on Eelworm in Potatoes in South Lincolnshire. —J. Helminth., III (5). 185–192. (W.L. 11224b.)Google Scholar
Peters, B. G. & Leiper, J. W. G. L., 1940.—Variations in Dilution-Counts of Helminth Eggs.—J. Helminth., XVIII, (2/3). 117–142. (W.L. 11224b.)CrossRefGoogle Scholar
Smedley, E. M., 1936.—The Action of Certain Halogen Compounds on the Potato Eelworm, Heterodera schachtii.—J. Helminth., XIV (1), 11–20. (W.L. 11224b.)Google Scholar