To evaluate the effect of mixed infection of two main pathogens of tomato in Iran, the interaction between tomato big bud phytoplasma (TBBP, 16SrII-D) and Tomato yellow leaf curl virus (TYLCV) was investigated under greenhouse condition. Tomato plants were graft-inoculated either with TBBP or TYLCV alone or together simultaneously and non-simultaneously. Symptoms expression and incubation period of the diseases were evaluated on all inoculated plants. To assess pathogen development, the concentrations of TBBP and TYLCV were compared at 10, 20, 40 and 70 days post-inoculation using quantitative PCR assays. In all replications, the tomato plants doubly inoculated with TBBP + TYLCV showed milder symptoms and longer incubation period than those singly inoculated with TBBP or TYLCV. Results also showed a reduction of TYLCV and TBBP concentrations in doubly inoculated plants when compared to single infection, although these reductions were not always statistically significant. In the tomato plants simultaneously inoculated with TBBP and TYLCV, the phytoplasma and virus concentrations were significantly lower at 70 days post-inoculation. These results suggest an antagonism between TYLCV and TBBP when infecting the tomato plant.

为了评估伊朗两种主要番茄病原体混合感染的效果，番茄大芽植物原质（TBBP，16SrII-D）与番茄黄叶卷曲病毒之间的相互作用（TYLCV）在温室条件下进行了研究。番茄植株单独或不同时用TBBP或TYLCV嫁接接种。在所有接种的植物上评估疾病的症状表达和潜伏期。为了评估病原体的发育，在接种后10、20、40和70天使用定量PCR分析法比较了TBBP和TYLCV的浓度。在所有复制中，双重接种TBBP + TYLCV的番茄植株比单独接种TBBP或TYLCV的番茄植株具有更温和的症状和更长的潜伏期。结果还显示，与单次感染相比，双重接种植物的TYLCV和TBBP浓度降低，尽管这些降低并不总是统计学上显着的。在同时接种了TBBP和TYLCV的番茄植株中，接种后70天的植原体和病毒浓度显着降低。这些结果表明，在感染番茄植物时，TYLCV和TBBP之间存在拮抗作用。