| Abstract |
The two-spotted spider mite, Tetranychus urticae Koch, are generally seen inhabiting the fruit trees vegetation resulting in low yield production together with fruits of low quality in Egypt.
The present study aimed to throw light on the side effect of organophosphorus, synthetic pyrethroids, fungicides, insect growth regulators, plant extract (Neemazal), and mineral oils and its mixtures with Basudin, Cascade and Admiral to select the suitable compound used against target pest and in the same time to control T. urticae, by single application, and the efficacy of Biocide compounds (Biofly, Trichoderma and Xentari) on different egg stages, adult females and biological aspects of T. urticae to minimize environmental hazards often associated with use of broad spectrum pesticides.
The results obtained revealed the following:
1- To evaluate the side effect of organophosphorus: prothiophos (Tokuthion) 50 % EC, Diazinon (Basudin) 60 % EC, Malathion (Malathion) 57 % EC, Fenitrothion (Sumithion) 50 % EC, and Phenthioate (Cidial) 50 % EC against egg and adult stages of T. urticae. Tokuthion was the most effective compound against 1, 2 and 3 days old eggs of T. urticae. Moreover, 3-days old eggs was more susceptible age than others to the above mentioned compounds. On the other hand, Basudin was more effective after 72 hr. against adult females of T. urticae.
2- The synthetic pyrethroids: Fenpropathrin (Meothrin) 20 % EC and Esfenvalerate (Sumi-Alpha) 5 % EC gave highly effective on eggs and adult females of T. urticae followed by Fenvalerate (Sumithion) 20 % EC and Lambda-cyhalothrin (Kendo) 5 % EC.
3- The side effect of fungicides: Mancozeb (Tridex) 75 % DG, Mancozeb 52 % + Copper oxychi 17.5 % (Mancoper) 69.5 % WP, Fosetylal + Folpet (Mika1) 75 % WP, Dromoconazole (Vectra) 40 % FL, Mancozeb (Nemespore) 80 % WP, Triforine (Saprol) 19 % EC, Captan (Captan) 50 % WP, Fenarimol (Rubigan) 12 % EC, and Procymidone (Sumisclex) 50 % WP gave a good results against egg stages of T. urticae than the adult stages. therefore, fungicides can be mixed with acaricides to control T. urticae at the severe infestation with T. urticae. But in early season, fungicides can be used without any acaricides to control T. urticae.
4- The present study dealt with the evaluation of Basudin 60 % EC at 300 cc/100 litre of water against the population density of T. urticae on apple trees. The obtained results indicated that the phosphorus compound Basudin, was decreased the population of T. urticae to 81.32 %.
5- To evaluate the side effect of some Biocide compounds, Beauveria bassiana (Biofly) 3 x 107 conidia, 100 cc/100litre of water, Trichoderma harzianum (Trichoderma), 250 cc/100 litre of water, and Bacillus thuringiensis (Xentari), 125 gm/100 litre of water, on different ages of egg stages and adult females of T. urticae, the effect of these compounds against egg stage were higher than that adult females of T. urticae. Biofly was higher effective on adult females followed by Trichoderma. Also, Biofly was highly effective on different ages of egg stages. Moreover, 3- days old eggs were more effective than the others ages of eggs.
6- The present study show that, the biological aspects of T. urticae, when treated one day old eggs with Biofly at 100 cc/100 litre of water, Trichoderma at 250 cc/100 litre of water, and Xentari at 125 gm/100 litre of water, increased the total immature stages, life cycle, generation period, oviposition period and decreased the average number of deposited eggs per female to 95.9 %; moreover, it caused 90 % mortality of immature stages.
7- The present study dealt with the evaluation of Biofly (Beauveria bassiana at 100 cc/100 litre of water) against T. urticae, under field conditions. The obtained results indicated that, after five days from application of B. bassiana against T. urticae, on apple trees gave 51.72 reduction percentage and then increased to 65.32 percentage of reduction after the second treatment. Three and fourth application with the fungus increased reduction gradually. The average percentage reduction was 71.06 after the fourth application.
8- To evaluate the effect of Flofenoxuron (Cascade 10 % DC), Pyriproxyfen (Admiral 10 % EC), Hexaflumuron (Consult 10 % EC), Lufenuron (Match 5 % EC), Tebufenzoide (Memic 2-f 5 % EC) and Triflumuron (Al- systin 48 % EC) were tested against egg stages and adult females of T. urticae. Results indicated that 3- days old eggs were more effective than 1- and 2-days old eggs, Cascade was highly effective on different ages of egg stages followed by Admiral especially 3- days old eggs of T. urticae. On the other hand, these compound gave higher effect on egg stages of T. urticae than adult females.
9- The present results show that, the biological aspects of T. urticae, when treated one day old eggs with Admiral at 75 cc/100 litre of water increased the total immature stages and generation period, but the oviposition period was highly decreased to 1.75 days compared with 8.8 days in control. On the other hand, the average number of deposited eggs per female decreased to 7 eggs in treated compared with 73.25 in control; moreover, it caused 84.20 % mortality of immature stages.
10- The evaluation of Neemazal (Azadirachtin) at 200 cc/l O litre of water on T. urticae. Results show that, the effect of Neemazal on the sensitivity of T. urticae, eggs increased by the increasing of their ages, it was found that 3¬days old eggs were more sensitive than 1- and 2-days old eggs. Moreover, the mortality percentages against larval stages increased after 48 hr., from treatment. Also, the repellency percentage of Neemazal against adult females of T. urticae increased after 24 and 48 hr. and then decreased after 72 hr., from treatment. On the other hand, the use of Neemazal against one day old eggs induced an obvious reduction in oviposition period, longevity, life span and the average number of deposited eggs per female; moreover, it caused 74.46 % mortality during immature stages and 89.9 % reduction of fecundity per female.
11- The effect of mineral oils (KZ oil) and its mixtures with Basudin 60 % EC, Cascade 10 % DC and Admiral 10 % EC, results indicated that 3-day old eggs was more susceptible than 1- and 2-days old eggs for Basudin 60 % EC, Cascade 10 % DC, Admiral 10 % EC and their mixtures with KZ oil. The present results clearly showed that these pesticides and their mixtures with KZ oil were more effective after 72 hr., than 24 and 48 hr. from treatment on adult females of T. urticae. On the other hand, eggs exhibited high sensitivity using these pesticides and their mixtures with KZ-oil than the adult females of T. urticae. Also, it seem that KZ oil at 1.0 litre/100 litre of water improved and increased the efficiency of Basudin and Cascade against T. urticae
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