Homoeopathica September 2003

by K. K. Khanna and S. Chandra

The effect of ten homoeopathic drugs on the spore germination of Pestalotia mangiferae, a fruit rot fungus, was studied. On the basis of result of in vivo studies with inhibitory doses of drugs,Lycopodium clavatum 190c was found to control the disease.
A number of methods are employed to control post-harvest decay of fruits, but each method has its limitation. Some homoeopathic drugs have been shown to induce toxic effects on phytopathogens. This report incorporates the results of in vitro and in vivo evaluation of some homoeopathic drugs against the causal agent of mango fruit rot.

Drugs used in the study were Arsenicum album, Kali iodatum, Lycopodium clavatum, Phosphorus, Thuja occidentalis, Withania somnifera, Blatta orientalis, Zincum sulphuricum, Filix mas and Kali muriaticum.
The fungitoxicity of drugs was determined in terms of the inhibition of spore germination of the causal fungus. The effect of various potencies (from 1 to 200c) of each drug was studied. The potencies were prepared in distilled water on the centesimal scale. Prior to use, the drugs were sterilized by filtration through bacterial filters.

Spores of the pathogens were suspended in different potencies of the drugs, and hanging drop technique of Hoffman was employed to determine percentage of spore germination: three replicates were taken for each treatment and the mean value of the replicates was recorded. Percentage spore germination was recorded after an incubation of 8-12 hours.

The drugs which completely inhibited the spore germination in vitro were screened for their efficacy in checking the fruit rot. For this purpose, healthy mango fruits, just ripe, of the variety Dasheri, were employed. Both pre- and post-inoculation treatments were given to the fruits. The fruits after disinfection were injured with a sterilized needle. The inoculum was provided in the form of spore suspension and the inoculated fruits were incubated for 24 hours. Dip treatments were given to the fruits for 3-5 minutes in each drug, and the treated fruits were stored in glass chamber at 24 C (-1 C). For pre-inoculation treatment, the injured fruits were dipped in each drug prior to inoculation.

In the control series, the inoculated fruits were dipped in sterilized distilled water instead of a drug. In all cases, 5 replicates of 12 fruits each were taken and the percentage fruit infected and percentage rot developed were determined after 8 days.

The effect of drugs on the spore germination of the fungus indicated that Phosphorus 50c,Lycopodium 190c, Withania somnifera 100c, Arsenicum album 1c, 89c and 90c and Zincum sulphuricum 1c and 2c completely inhibited the spore germination. Other drugs either did not affect or only reduced the percentage of spore germination. Thus, only those drugs which completely inhibited the spore germination were evaluated for their efficacy in checking the fruit rot. The results presented in the table indicate that, except for Lycopodium 190c, none of the drugs tested could reduce the percentage of fruit infected.

They further indicate that, although all the inhibitory potencies reduced the percentage of rot,Lycopodium clavatum 190c was found to be most effective in both the types of treatment. Thus only Lycopodium 190c was effective both in reducing the percentage fruit infection as well as percentage rot.

Analysis of the extracts of treated fruits with Lycopodium 190c showed that the drug did not induce any change in amino acid, amide, organic acid, sugar and vitamin C contents of the fruits. On the basis of the above results, Lycopodium 190c may be safely recommended for the control of mango fruit rot caused by Pestoliatia mangiferae.

This was research conducted at the University of Allahabad’s Botany Department in 1977.

Efficacy of various homœopathic drugs in checking mango fruit rot.*

* Results were statistically analysed for analysis of variance and Duncan’s Multiple Range Test at 5% level. Numbers followed by the same letter are not significantly different within columns.

** PFI, percentage fruit infected.

*** PRD, percentage rot developed.