بررسي ويژگي‌هاي ريخت‌شناسي و بيوشيميايي موثر بر فراواني و ترجيح ميزباني تريپس غربي گل بر ارقام مختلف رز شاخه بريده

Frankliniella occidentalis (Western flower thrips) is one of the most destructive pests of rose (Rosa hybrida),causing substantial reductions in quality an‎d market value, particularly in cut-rose production systems. This study aimed to identify resistant an‎d susceptible rose cultivars an‎d to investigate key biological, morphological, an‎d biochemical traits influencing thrips attraction an‎d damage severity. In the first phase, thrips infestation was monitored in a commercial greenhouse across 13 rose cultivars using a completely ran‎domized block design during three monthly sampling periods. Based on the infestation levels observed, eight cultivars representing the highest an‎d lowest levels of thrips contamination were selec‎ted for laboratory color-preference assays. For this purpose, in each replicate, eight flower stems from eight different cultivars were placed inside transparent boxes under a completely ran‎domized design, an‎d thrips selec‎tion behavior was eva‎luated. Results indicated that the cultivars ‘Samurai’ an‎d ‘Silverine’ exhibited the lowest attractiveness to thrips an‎d were categorized as resistant, whereas ‘Avalanche’ an‎d ‘Pearl’ showed the highest attraction an‎d were identified as susceptible. In the final phase, grafted plants of these four cultivars were established in the research greenhouse of Isfahan University of Technology. After plant establishment an‎d flowering, adult thrips were released at the full-bloom stage. Several parameters—including thrips population per flower, number of damaged petals, visual damage rating, biochemical traits (total phenolics, protein, carbohydrate, an‎d anthocyanin content), an‎d selec‎ted morphological characteristics—were assessed. The cultivar ‘Avalanche’ exhibited the highest thrips attraction an‎d damage levels throughout all sampling periods, whereas ‘Samurai’ showed the lowest infestation an‎d injury. Biochemically, resistant cultivars (‘Samurai’ an‎d ‘Silverine’) contained significantly higher levels of total phenolics an‎d anthocyanins, while susceptible cultivars (‘Avalanche’ an‎d ‘Pearl’) had higher nitrogen content. These results highlight the defensive role of phenolic compounds an‎d suggest a potential relationship between nitrogen content an‎d thrips feeding preference. In addition, petal calcium content was notably higher in ‘Samurai’ compared to the other cultivars. Overall, the findings demonstrate that the combined effects of floral color, petal morphological structure, an‎d biochemical composition play crucial roles in rose resistance to thrips. Among the eva‎luated cultivars, ‘Samurai’ can serve as a valuable source of resistance for integrated pest management programs an‎d future rose breeding efforts.

نعمت اله اعتمادي شلمزاري , جهانگير خواجه علي

بهاره دانشمند

علي نيكبخت , لادن طلايي