Investigating the responses of the pest and plant to two spotted mite [Tetranychus urticae (Koch)] feeding on different tomato varieties


Thesis Type: Postgraduate

Institution Of The Thesis: Bursa Uludağ University, FEN BİLİMLERİ ENSTİTÜSÜ, Turkey

Approval Date: 2013

Thesis Language: Turkish

Student: Narin Keskin

Supervisor: NABİ ALPER KUMRAL

Abstract:

Tetranychus urticae (Koch) (Acari: Tetranychidae) is a serious pest of several crops particulary in tomato. Chemical control of the spider mite on this vegetable has not been very successful due to fastly develop to resistant to acaricides. T. urticae performs differentially depend on tomato varieties. Plant trichomes are implicated in a variety of adaptive processes, including defense against herbivores as well as spider mites. The aim of study was to evaluate the plant features (density of trichomes type 1 and type 4) and survival, development, oviposition and life table parameters of the T.urticae on ten tomato varieties. In addition, the current study was to establish the relationships between the damages of the mites and its population level on different tomato variety. We used a variety, Beaufort, derived from cross between the wild tomato, Lycopersicon hirsutum and the cultivated tomato L. esculentum, and nine cultivated varieties, Aytina, Beril, Bt-236, Elegro, Impala, Platinium, Simena, Troy and Y-67. The study showed that when T. urticae fed on Beaufort tomato variety, rm (0,121), Ro (5,79) and GRR (5,79) were lower than the mite feds on the other varieties. Also, the mite population level on this varietiy was significantly lower compared with that on other tomato varieties. However, the lowest survival rate was established in Beaufort variety. Densities of trichome type 1 and especially grandular type 4 were significantly higher than those of others. The tolerance of this variety was found higher compared the damage of mites on other variety. According to life table parameters, population levels and damage rates of T. urticae, stake tomato varieties, Y-67 and Aytina, were found very susceptible to the mite. In contrary, the density of type 4 trichome was determined lower than Beaufort and some other cultivated varieties. Bt-236 variety was found very close to Beaufort in terms of life table parameter, the survival rates, the damage rates and the density of type 4 on leaves surface of it. Although the population level of T. urticae was found very low in Elegro, the damage rate was occurred higher in this variety. The mite damage rates per female mites were the highest on Y-67, Elegro and Aytina, intermediate on Simena, Troy, Beril and Platinium, and the lowest on Beaufort, Impala and Bt-236.