花蓟马与向日葵籽粒锈斑发生的关系

向日葵是我国重要的油料经济作物，籽粒锈斑近几年在向日葵籽粒上发生，严重影响向日葵籽粒的品质，然而关于向日葵籽粒锈斑的成因目前并不清楚。本文在内蒙古向日葵主产区，选择向日葵籽粒锈斑发生严重的区域，通过大田套袋技术并结合室内接虫试验，对向日葵籽粒锈斑的成因进行初步探索。结果表明，2020年五原县、乌拉特前旗及2021年五原县向日葵经套袋处理后，花蓟马Frankliniella intonsa Trybom的数量分别比对照降低了13.23、1.33头和191.53头，向日葵籽粒锈斑的发病率比对照(未套袋)相应降低了28.19%、12.07%和60.02%,与对照有极显著差异(P<0.01),花蓟马数量与向日葵籽粒锈斑的发病率呈现出显著的正相关关系。同时，室内在向日葵花盘上接种花蓟马后向日葵籽粒锈斑的发病率为22.67%,而未接虫的向日葵籽粒锈斑没有发病。另外，统计显示向日葵花盘外侧花蓟马数量显著大于中间和内层，向日葵籽粒锈斑发病率也呈现相同的规律。由此推测，向日葵籽粒锈斑的发生主要与花蓟马的活动有关，花蓟马可能是造成向日葵籽粒锈斑的主要成因。

Relation of Frankliniella intonsa and occurrence of sunflower seedcoat rust

Sunflower is an important oil crop in China. Seedcoat rust has occurred on sunflower seeds in recent years, and the quality of sunflower seeds has been affected heavily. However, the cause of sunflower seedcoat rust is still elusive. In this paper, the causes of sunflower seedcoat rust were investigated through bagging technique in the fields of the main sunflower producing areas in Inner Mongolia and inoculating Frankliniella intonsa (Trybom) in laboratory. The results showed that the number of F. intonsa decreased by 13.23 (Wuyuan county, 2020), 1.33 (Urad Front Banner, 2020) and 191.53 (Wuyuan county, 2021) on sunflower disc bagging compared with the non-bagging control, respectively, and the incidence rate of sunflower seedcoat rust decreased by 28.19% , 12.07% and 60.02%, respectively, compared with the non-bagging control. There was a significant positive correlation between the number of F. intonsa and the incidence rate of sunflower seedcoat rust (P<0.01). At the same time, the incidence rate of sunflower seedcoat rust was 22.67% after inoculating F. intonsa on sunflower disc in laboratory, while the sunflower seedcoat rust did not occur without inoculating. In addition, the statistics data showed that number of F. intonsa on the outside of sunflower disk was significantly more than that of the middle and inner, and the incidence rate of sunflower seedcoat rust had the same rule too. It is inferred that the sunflower seedcoat rust is mainly associated with the F. intonsa, and the sunflower seedcoat rust would be mainly caused by F. intonsa.