本研究以矮化梨品种‘601D’及其突变体‘601T’为材料，研究比较了它们的生物学特性，并进一步探讨了601D的矮化机理。生物学特性表明，601D的节间短，树体短而紧凑，叶片厚而宽，气孔密度低，气孔（直径）大，光合能力强。601T的生物学特性表现出显著的差异。内源激素检测结果表明，601D的脱落酸（ABA）、ABA葡萄糖酯和GA4含量较高，而反式玉米素含量较低。通过转录组学分析，发现ABA的生物合成和代谢途径存在显著差异。相关转录因子如bHLH、WRKY和Homeobox等也参与了植物矮化的调控。因此，我们研究了三种与601T有明显差异的激素，发现只有ABA可以诱导601T恢复矮化植株表型。因此，我们认为601D的矮化是由于ABA的过度积累所致。本研究为矮化品种的选育提供了新的理论依据。

In order to establish double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) for detection of duck or goose flavivirus, polyclonal antibody against the flavivirus strain JS804 in geese and monoclonal antibody against the E protein of flavivirus strain JS804 in geese were used as the capture antibody and detection antibody, respectively. The optimal dilution of the capture antibody and detecting antibody capable of detecting the flavivirus strain JS804 in geese were 1:3 200 and 1:160 in the check-board titration, respectively. The reaction time of sample was 1 h, and the optimal working dilution of HRP-labeled goat-anti-mouse IgG was 1:10 000. The positive standard value was 0.247 (OD450 nm). The geese flavivirus could be detected at a minimal concentration of 1.875 μg mL-1. The ELISA had no cross-reaction with Newcastle disease virus (NDV), Avian influenza virus (AIV), Infectious bronchitis virus (IBV), Infectious bursal disease virus (IBDV), Duck hepatitis virus (DHV), and Gosling plague virus (GPV). Twenty clinical samples were detected by the DAS-ELISA and RT-PCR respectively, with the agreement rate of 75%. The results revealed that the DAS-ELISA possessed favorable specificity and higher sensitivity, indicating a suitable method for rapid detection of the duck or goose flavivirus.