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Abstract Tomato, Lycopersicon esculentum, Miller is one of the economically important vegetables in Egypt as well as in the world and many pests attacking plants causing serious damage by sucking the sab, feeding on leaves , branches and fruits one of the most serious pest is Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae). The tomato borer, Tuta absoluta was initially reported in Egypt in late 2009, and has subsequently spread throughout the majority of crops. The highest of damaged fruits reached to 100 % damage in farms by Tuta absoluta. The present study aims to investigate the following points: 1. Ecological studies: 1.1. Survey of the different pests infesting tomato plants: To survey the pests and beneficial insects, the experiment was carried out in three Governorates (Menoufia, Giza and Sharkia). Periodical visits were conducted during two seasons extended from 2012, until 2013, year. Samples of tomato plants were examined, the different arthropods were classified into different categories and counted and calculated as monthly average per ten leaves. The result obtained that there are ten injurious species were recorded during this study, those belonging to eight orders, Orthoptera, Hemiptera, Thysanoptera, Neuroptera, Lepidoptera, Coleoptera, Diptera and Hymenoptera. Five predators and one parasitoid associated with the insect pests on tomato plants, two Acariformes pests and one snail were recorded in different Governorates of study. The highest peak of occurrence period for different surveyed insects N. viridula and G. gryllotalpa occupied March A. gassupii and T. absoluta occurred during May, T. tabaci, H. aremigra and P. operaulella were observed in July, L. trifolii was recorded with highest number in September at last during October both B. tabaci and S. littoralis reached to the peak of abundance, in the tested three Governorates (Menoufia, Giza and Sharkia). On the other hand the natural enemies recorded the peak of abundance during May and June for C. carenea, O. albidipenis occurred with high number during July and August and also in the same period were observed N. tenuis, C. undecimpunctata and Trichogramma achaea reached highest peaks. Ending during March and April S. corollae reached the highest number of abundant in the three Governorates. (Menoufia, Giza and Sharkia). 1-2 - Population density of different stages and number of mines of Tuta absoluta on tomato plants in Menoufia region: 1.2.1. Population density of the tomato borer, T. absoluta eggs: Results the total mean numbers of eggs during the both two plantations of 2013 and 2014 the data showed that , the winter plantation recorded 5.6 eggs/ 10 leaves, while during summer plantation the total mean numbers of eggs reached to 84.2 eggs/ 10 leaves. The egg percentages during the winter plantation recorded 17.9% during Sep., 28, Oct., 5 and Oct., 26 and prevailing condition ranged between 26- 30 °C and 67.5% - 84.5% R.H. The second season showed that the highest percentages of egg occurred during the 2nd and 3rd. weeks of Mar., 2014 with 24.6% and 13.9%, respectively, where the natural conditions were 25.8 °C – 28.0 °C and 48.4%- 53% R.H. 1.2.2. Population density of the tomato borer, T. absoluta larvae: Results showed that the total mean number of larvae during the winter plantation recorded 8.9 individuals/ 10 leaves, while during the summer plantation of study reached to 75.9 larvae/ 10 leaves. The percentage values of larval stage recorded highest value of 22.5% during last week of September and the first week of November, when the temperature ranged 27- 30 °C and R.H. were between 77.0- 84.5% during the winter season of 2013. In the second plantation the highest percentage reached to 20.7% during the first week of April, 2014 and the natural conditions recorded 31.0 °C and 48.1% R.H. 1.2.3. Population density of the tomato borer, T. absoluta pupae: Results revealed that the total number of pupae during the winter plantation recorded low density (2.0 pupae/ plant), while the population density during summer plantation recorded total mean number of 39.5 pupae/ 10 plant. The percentage values of pupae occurred in high value of 25.0% during first week and last week of Oct. While, in the second season the percentage of pupae recorded the highest value of 14.4% during last week of April and first week of May. The prevailing natural conditions ranged between 26-27 °C and 30 °C and 67.5- 82.8% and 48.8- 52.0% in both seasons, respectively. 1.2.4. Population density of the tomato borer, T. absoluta moth: As for the two plantations of study, the total numbers of Tuta absoluta moths showed so high total number during the summer plantation (3546.3 moths); while during the winter plantation the moth mean numbers occurred with too low recording 358.0 moths. The highest percentage of number of moths relative to the total number of moth in both plantation showed that during the winter plantation, the highest percentage reached 25.1% (Oct., 19), when temperature degrees and % R.H. were 27.0 °C and 75.0% R.H. and during Nov. 30 reaching 37.7%, when the natural factors were 23.0 °C and 60% R.H. In the summer plantation the highest percentage recorded 28.6% during March 28 and the temperature was 28.0 °C and % R.H. was 48.4. 1.2.5. Population density of the tomato borer, T. absoluta mines: The total mean number of mines during both plantations showed that the total numbers of mines during the first plantation was 18.9 mines/ 10 leaves, while the second one was 199.0 mines/ 10 leaves. The percentages values of mines reached to 33.3% during mid- October, when prevailing conditions were 31.0 °C and 65.1%. During the summer plantation the highest percentages occurred during 1st week of April and 1st week of May, 2014, the natural conditions ranged between 30.0- 31.0 °C and 48.1- 52.0% R.H. 1-3 Effect of number of pheromone traps on the trapped numbers of Tuta absoluta moths in Menoufia region: The results about the mean numbers of larval stage on tomato leaves and fruits and trapped moths per traps in both two cases of study, the (5 traps/ Fadden) and (14 traps/ Fadden) showed that the mean numbers of trapped moths recorded five peaks ranged between 352, 5 – 972.5 insects / trap for (5 traps/ Fadden), while in case of (14 traps/ Fadden), the mean numbers recorded three peaks only and ranged 31.3 – 470.0 moths / traps. In the other side, the mean number of larvae / 10 tomato leaves and fruits ranged between 0.3 – 7.5 larvae / 10 leaves and 1 – 2.8 larvae / fruit in case of (5 traps/ Fadden) , whereas in the second case of (14 traps/ Fadden) , the mean numbers recorded lowest numbers of 7.0 and the highest numbers 21.0 larvae / leaves , while the fruits received mean numbers ranged 10.0 – 17.0 larvae / 10 fruits, the results summarized reveal that the mean numbers of trapped moths were higher in case of (5 traps/ Fadden) , while the mean numbers of larvae on tomato leaves and fruits showed higher numbers in case of (14 traps / Fadden) . The previous data concluded that, application of 14 traps / Feddan captured low numbers of T. absoluta male lead to highly leaves and fruit damage. The may be refer to, the high number of traps caused disturbance more than capture of T .absoluta male , which give chances to mating at later time . 1.4 Effect of the predator Nesidocoris tenuis (Reuter) Hemiptera:Miridae) on Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) and its damage to tomato plant: In summer tomato plantation during Jul., to Aug., 2015, the average numbers of T. absoluta sharply decreased affected by the high temperature (36 and 36.5°C) and relative humidity (62 and 65 R.H%) recording the lowest numbers of moths of T. absoluta / trap, (1-2) , while the predator appeared with average of 5.75 and 6.75 individuals / plant, respectively. So, the predator directed to feed on peduncle and side branches of tomato plants and recorded 2.25 in small branched and 5 in petioles of flowers / plant It was deserved that the mired predator Nesidocoris tenuis Reuter (Hemiptera: Miridae) attack the insect pest Tuta absoluta (Lepidoptera: Gellchiidae) but started to feed on the host plants when the prey numbers decreased or not available. The damage occurred on the small branches and petiole of flowers forming. Therefore this information must be taken in minded when this predator is released in IPM control program. 2- The effect of suggested IPM program on Tuta absoluta population on tomato plants in Menoufia Governorate: It is known that the leaf miner insects are very difficult control. The infestation occurs in any stages of plant growth causing considerable economic damage to yield to one degree or another. Data obtained were discussed as follows: 2 -1- The egg stage: The mean number of T. absoluta eggs indicated that the farmer application recorded 4.68 eggs / 10 leaves, while the IPM suggestion showed 0.42 eggs / 10 leaves. The statistical analysis indicated significant difference between the two applications 2 -2 -The larval stage: The statistical analysis had significant difference between the two applications. The farmer application recoded 10.55 larvae / 10 leaves, while IPM suggestion had 0.27 larvae / 10 leaves. 2 -3 -The moth stage: Statistical analysis showed high significant difference between the two tested applications. The general mean of farmer application recorded 174.64 male moth / trap, while the tested IPM program had 624.54 male moth / trap. 2 - 4 -The mines: Statistical analysis showed high significant difference between the two tested applications. The general mean of farmer application had 5.04 mines / 10 leaves and the tested IPM program recorded 0.87 mines / 10 leaves. - Damaged of fruits: The larval activity indicated by the damaged fruits/ 10 fruits, fruits damage caused by T. absoluta larval stages were particularly low with an average of 1.63 damaged fruits per 10 fruits in IPM program. However, the damaged fruits were very high, with an average of 6.83 damaged fruits/ 10 fruits in case of farmer field applications. |