Anzeiger für Schädlingskunde, Pflanzenschutz, Umweltschutz (1990) 63, 14-15

Gamalat Y. Osman (1990)
Preliminary study on induction of sex reversal in Meloidogyne javanica (Chitwood) and Tylenchulus semipenetrans (Cobb) nematodes by testosterone
Anzeiger für Schädlingskunde, Pflanzenschutz, Umweltschutz 63 (1), 14-15
Abstract: Sex hormone, testosterone, was used to induce the function of sex reversal in the two nematode genera, by treating M. javanica and T. semipenetrans egg-masses and new hatched larvae. The percentages of males were 80 and 62.5%, respectively, when applying testosterone three times, the first on egg-masses, the second and the third on hatched larvae at 10 ppm concentration. Percentage of males was increased by 45.83 for M. javanica in comparison with the check. Also, the sex hormone decreased the percentage of citrus nematode females that infected the root with 80%. Consequently, this means that the males percentage was increased. In addition, the reduction percentages of the total nematode population for M. javanica and T. semipenetrans treated with testosterone were 33.33 and 80%, respectively.
These results indicate that the use of testosterone to induce the function of sex reversal is promising as a new approach for controlling parasitic nematodes, M. javanica and T. semipenetrans on tomato and sur orange, respectively. Testosterone showed two dimensions in this respect, the first is in changing the population sex ratio, where the percentages of males were increasing and decreasing the total population in comparison with the check in both nematode genera.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website

Research topic(s) for pests/diseases/weeds:
general biology - morphology - evolution
control - general

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Meloidogyne javanica
	Tylenchulus semipenetrans