RESUMEN
The present study was initiated to elucidate the effect of potato tubers treatment using fine dusts of Psidium guajava, Cymbopogon citratus, talc powder and their progressive dilutions(w/w) on the fitness components of raised generations of the potato tuber moth (PTM), Phthorimaea operculella. Results showed a direct as well as cumulative delayed effect of the tested plants fine dusts, either alone or admixed with talc powder in progressive dilutions from 5% up to 50% w/w on the viability of developing immatures and potentiality of adult moths. The revealed effects of each of the tested crude plant fine dusts or talc powder alone and/or their progressive dilutions (w/w) could be explained briefly as gradual significant shortening of life span of both sexes, prolongation of larval duration, reduction in number of raised pupae, increase of malformed ones, sharp decrease in the rate of emerged moths, deposited eggs, and developing of immatures; According to lower used dilutions of each tested plant fine dust from 5% to 20%, the complete inhibition of reproductive potential of both adult sexes, the going on metamorphic development of deposited eggs and/or raised immatures of the following generation, after the treatment of parent one, had been revealed the following distinct failure of: a) F1 development after former treatment of parent generation with the higher concentrations of 30-50% of both tested plant fine dusts and the lower prepared dilutions (10% and 20% (w/w)) of both the tested Psidium guajava and (20% (w/w)) Cymbopogom citratus plant fine dusts, resulted in fewer number of the emerged moths that were unviable, weak, sterile and died before induction the F1 progeny, b) F2 development due to the former treatment of the parents with talc powder, Psidium guajava fine dusts alone or its prepared dilutions of (5% (w/w)) and Cymbopogom citratus dilution of (10%(w/w)) gave unviable weak and sterile moths unable to induce the F2 progeny, c) F3 development post former treatment of the parent generations with Cymbopogom citratus dilution of 5% (w/w) induced unviable sterile moths and died after emergence and d) F4 development owing to the former parent treatment with Cymbopogon citratus fine dust alone; The complete failure of each of the above mentioned generations could be attributed to the cumulative effect of induced recessive lethal genes in both sexes along the extended period of each of these following generations, post former treatment of parent one, causing apparent undesirable effects, that appeared at the beginning of each of them.
