الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Tomato plants are considered as an important economic vegetable crops. Tomatoes are produced all year round, either in greenhouses or open field. It also is considered one of the crops that are used for export.Tomato plants are infested with many important pests,(i .e . whitefly, aphids, potato tubers moth and recently, the tomato borer, T. absoluta). T. absoluta is considered one of most important pests on tomato crop and cause severe losses. It was recorded for the first time in Egypt in late 2009.It also infest other Solanaceae crops such as potatoes and eggplants. The scope of this study aimed to cover the ecological and control studies of T. absoluta on certain Solanaceae plants and certain commercial tomato varieties that are in Egypt also insect identification using modern biotechnology.
The obtained results are summarized as follows:
Ecological study:
Host preference of T. absoluta on certain solanaceous plants:
Tomato hybrid Alissa F1 harbored the most relative density of T. absoluta larvae compared with pepper (California wonder) - eggplant (Black Shanta F1) - potato (Santana) during two years of the study 2013 and 2014. Results recorded the highest population density of T. absoluta larvae on tomato plants in early summer and summer plantations of 2013, with average numbers of 8 and 3.62 larvae/10 leaflets, respectively. Recorded results during the second year (2014) averaged 7 and 3.52 larvae/10 leaflets.
Susceptibility of certain tomato cultivars to T. absoluta infestation:
The susceptibility of some tomato cultivars to infestation with T. absoluta, in relation to leaflet trichomes was studied. Five tomato cultivars; Alissa F1, Super strain B, G.S 12 F1, E603 F1(Logain) and Indos were planted in both early summer and summer plantations; 2013 and 2014. These results indicated that seasonal abundance was higher in early summer plantation 2013 than that recorded in plantation 2014 with seasonal mean numbers of 5.93 and 5.20 larvae/10 leaflets for the two plantations, respectively. These results indicated that seasonal abundance was higher in summer plantation 2013, than that was recorded in plantation 2014 with seasonal mean numbers of 3.44 and 3.05 larvae/10 leaflets, respectively. The highest seasonal mean number was recorded on Alissa F1cultivar with mean number of 5.53 larvae/10 leaflets, for both studied the plantations. While the lowest mean number (2.99 larvae/10 leaflets) was recorded on Logain (E603 F1) cultivar, for the two plantations.
Effect of tomato leaflet trichomes on T. absoluta infestation:
There are two types of trichomes in both tomato leaflet surfaces in all the five tomato cultivars; one of them is a non glandular type (III) and the other one is a glandular type (VI). Statistical analysis of simple correlation among these two types of trichome’s density, length and width of five tomato cultivars and T. absoluta infestation, showed negative significant relationship (r= -0.89 P= 0.04) between the glandular trichome (VI) density (numbers) and T. absoluta infestation. The highest mean number of this trichome type was detected in Logain (E603F1) cultivar (22.6 trichome/1mm2 leaflet), followed by Indos, Super strain B, GS 12F1 and Alissa F1 with mean numbers of 8, 5.4, 3.8 and 3.2 trichome/1mm2 leaflet. In addition, the length of non glandulartrichomes was correlated negatively and insignificantly with T. absoluta infestation (r= -0.56, P= 0.31) .
Relation between mean number of glandular trichomes on tomato cultivars leaflets and percent damaged fruits byT. absoluta.
The level of infestation of fruit tomatoes damaged by T. absoluta of five tomato cultivars (Alissa F1, Super strain B, G.S 12 F1, E603 F1 (Logain) &Indos) at harvesting stage of early summer plantation in the two plantations; 2013 and 2014 was evaluated. Statistical analysis of variances indicated significant differences among mean percentage of damaged fruits by T. absoluta, where the higher percentage of damaged fruits was recorded on Alissa F1 36.00% and 42.84% followed by GS 12 F1 with percentage of 34.24% and 35.54% then Indos with percentage of 32.27% and 23.59%, thereafter Super Strain B (27.83% and 22.11). On the other hand the lowest percentage of damaged fruit was recorded on Logain E603 F1 (14.78% and 7.11% in both years, respectively). In addition, the glandular trichomes was negatively significant correlated with mean percentage of damaged fruits by T. absoluta (r = -0.94, P=0.01 & r = -0.87, P= 0.05) in the both plantations; 2013 and 2014, respectively. Meanwile, the highest mean number of this trichome type was detected in Logain (E603F1) cultivar (22.6 trichome/ 1mm2leaflet).
Role of Allelochemicals in resistance of tomato cultivars against T.absoluta
Volatile compounds:
The oil analysis by GC/MS of the essential oil revealed the presence of 33 peaks. These analyses also revealed that the major identified aliphatic hydrocarbon components in the leaflets oil of Logain and Alissa tomato cvs. (The lowest and the highest infestation with T. absoluta) were Octacosane (25.35%, 12.52%), Tetratriacontane (22.07%,4.30%), Hexacosane (18.69%,6.26%), Triacontane (10.55%, 5.92%), Heptacosane (8.43%, 14.00%), Nonacosane (6.56%,4.26%), Hexatriacontane (1.83%,0.00%) and Tetracosane (1.58%,8.87%), respectively. The presence of the high contents the toxic and repellence volatile compounds (the two hydrocarbons octacosane and hexacosane) in Logain tomato cv. and the high content of the attractant hydrocarbon tetracosane in Alissa cv.. can be interpretation of susceptibility of Logain and Alissa tomato cvs. toT. asolutainfestation.
Acylsugar:
The results indicated that, Logain tomato cv. was achieved the highest glandular trichomes density and acylsugar content (22.6 trichomes/1mm and 125.67ug/g fresh weight), respectively with the lowest infestation rate (7.00 larvae/ 10 leaflets). While, the lowest glandular trichomes density and acylsugar content (3.20 trichomes/1mm2 and 101.33±3.21ug/gmfresh weight), respectively with the highest infestation rate (7.00 Larvae/ 10 leaflets) werecorrelated with the high susceptibility Alissa tomato cv. rate (2.62 larvae/ 10 leaflets).
Phenolics, Flavonoids and Alkaloids contents.
Logain cultivar the most ressistant to infestation with T. absoluta (2.62 Larvae/ 10 leaflets), because of the highest contents of phenolics, flavonoids and alkaloids(8.28±0.13mg/gdw), 34.47±0.08O.D./gdwand 18.40±0.95g/100gfw), respectively. While, Alissa cultivar was the most susceptible one to the infestation rate (7.00 larvae/10 leaflets),due to the lowest contents of phenolics, flavonoids and alkaloids (5.49±0.13, 25.43±0.08 and 10.53±0.46), respectively.
Total carbohydrates and proteins contents:
The results showed that, the highest carbohydrates and proteins contents were recorded in Logain cultivar (210.67and 53.50mg/gdw), respectively, while, the highest susceptible Alissacultivar was contained the lowest carbohydrates and proteins (158.67 and 38.83mg/gdw ), respectively.
Seasonal abundance of T. absolutaonAlissaand Logain tomato hybrids:
Early summer plantation, 2013:
During early summer plantation, 2013, T. absoluta larvae were occurred from Mar. 5th to Jun. 4th. Four peaks of activity were recorded on Alissa and only three peaks were on logian. The highest population density of T. absoluta on Alissa F1 tomato hybridwasrecorded on May 14thas 25.33larvae/10 leaflets and 19 N. tenuis predator/plant . On the other hand, the highest peak of T. absoluta population on Logain E603 F1 tomato hybrid was recorded on May 22nd as 10.67 larvae/10 leaflets and 9 predators/plant.
Summer plantation, 2013:
During summer plantation, 2013, density of tomato borer, T. absoluta larvae were in few number and occurred from July 2nd to Oct.1st . The highest population density of T. absoluta on Alissa was recorded on July 9th as 5.33 larvae/10 leaflets and 3.67 predators/plant . Maximum population density for Logain was recorded on Aug. 20 as 5.00 larvae/10 leaflets and 4.33 predators/plant.
Early summer plantation, 2014:
During early summer plantation, 2014, T. absoluta larvae were found from Mar. 4th to Jun. 3th. Four peaks of activity were recorded on Alissa and only three peaks were on logian. The highest activity of T.absoluta populations on Alissa was recorded on Apr. 22 as 12.33larvae/10 leaflets and 14.67 predators/plant. On the other hand, the highest peak of T. absoluta population on Logain was recorded on Mar. 25 as 7.67 larvae/10 leaflets and 4 predators/plant.
Summer plantation, 2014:
During summer plantation, 2013, T. absoluta larvae were appeared from July 1th to Sep. 30 . The highest population density of this pest on Alissa and Logain tomato hybrids was recorded on Aug. 12th as 7.00 and 6.33 larvae/10 leaflets, respectively and 4.33 and 4.00 predators/plant.
Effect of some weather factors on population dynamics of T. absoluta as well as the relation to the predator N. tenuis.
In this part of the study of the relationship between three weather factors (maximum, minimum temperatures and relative humidity) and predator N. tenuis were tested to clarify their simultaneous effects on the population dynamics of T. absoluta infesting tomato cultivars at Qaha region (Qalyubiya Governorate) during early and summer plantations throughout two successive plantations; 2013 and 2014.
On Alissa tomato hybrid:
In early summer plantation 2013, simple correlation analysis indicated insignificant relationship between the weekly average maximum and minimum temperatures and relative humidity and population of T. absoluta larvae. While the predator was related significantly and positively with the mean number of T. absoluta larvae (r = 0.97, P = 0.001).
In summer plantation 2013, simple correlation analysis indicated insignificant relationship between the weekly average maximum, minimum temperature, relative humidity and predator with population of T. absoluta larvae.
The combined effect (EV %) of the three weather factors as abiotic factors was 33 and 14%, and EV % of the predator N. tenuis as biotic factor was 94 and 3.2 % in early and summer plantations 2013, respectively.
In early summer plantation 2014, simple correlation analysis indicated insignificant relationship between the weekly average maximum and minimum temperatures and relative humidity with population of T. absoluta larvae, while the predator was related significantly and positively with the mean number of T. absoluta larvae (r= 0.76, P=0.001).
In summer plantation 2014, simple correlation analysis indicated insignificant relationships between the weekly average maximum and minimum temperatures and relative humidity with population of T. absoluta larvae. On the other hand, predator ones was significantly positive with the mean number of this pest (r = 0.81 P =0.005).
The three studied weather factors or abiotic factors affected together (EV%) by 10 and 33% on the mean number of larvae in early summer and summer plantations. In case of the predator as biotic factor (EV%), it affected by 58 and 65%, respectively.
On Logaintomato hybrid:
In early summer plantation 2013, simple correlation analysis indicated insignificant relationships between the weekly average maximum, minimum temperatures and relative humidity and population of T. absoluta larvae. While the predator was related significantly and positively with the mean number of T. absoluta larvae (r = 0.95, P = 0.001).
In summer plantation 2013, simple correlation analysis indicated insignificant relationship between the weekly average maximum and minimum temperatures and relative humidity with population of T. absoluta larvae. On the other hand, relation between mean number of this pest and predator one was significantly positive (r = 0.70 P = 0.01).
The combined effect (EV %) of the three weather factors as abiotic factors was 38 and 47%, and EV % of the predator N. tenuis as biotic factor was 90 and 49% in early and summer plantations 2013, respectively.
In early summer plantation 2014, simple correlation analysis indicated significant negative relationship between the weekly average maximum and minimum temperature (r = -0.64 P = 0.01 and r = -0.66 P = 0.01, respectively) with population of T. absoluta larvae while relative humidity was insignificantly relation. On the other hand, relation between mean number of this pest and predator one was significantly positive (r = 0.83 P = 0.002).
In summer plantation 2014, simple correlation analysis indicated insignificant relationships between the weekly average maximum temperature and relative humidity with population of T. absoluta larvae. On the other hand, minimum temperature and predator was significant positive relationship (r= 0.73 P= 0.003 and r= 0.86 P=0.001, respectively).
The three studied weather factors or abiotic factors affected together (EV%) by 45 and 61% on the mean number of larvae in early summer and summer plantation. In case of the predator as biotic factor (EV%), it only affected by 69 and 74%, respectively.
Using some of bio-agent for controlling T. absoluta.
Microbial entomopathogenic bacteria (Trade name: Protecto 9.4% WP, and active ingredient: Bacillus thuringiensis var. kurstaki.) was used against larval infestation, also egg parasitoid, Trichogramma evanescens was used on T. absoluta eggs on tomato hybrid (Alissa F1) during the early summer plantation of 2014 and 2015. These results showed that T. evanescens was more potent according to reduction percentages in T. absoluta larvae in plantation 2014 and 2015 (63.89% and 62.20%, respectively) than Protecto 9.4% WP (55.55% and 48.61%, respectively). Through this study, it can be concluded that using of T. evanescens was more effective to control T. absoluta because it gave higher reduction percentages in larval infestation.
Molecular identification of T. absoluta.
The result of PCR amplifications of the five tested samples (Aswan, Minya, El sharkia, Kafr El Sheikh and Sinai) with Cytochrome c oxidase subunit I gene (MT-COI) were analyzed andsequenced. The sequences were blasted into GenBank database, reviewing and compilation. The sequences analysis showed that only one biotype of T. absoluta pest present in Egypt. The dendrogram data reflects the presence of high gene flow among the T. absoluta species collected from Mediterranean Basin and other parts over the Globe. Also, the data analysis showed that T. absoluta pest has ability to adapt with various environmental conditions. This is the first time to performed this study in Egypt.