Physiological quality of tomato seeds treated with polymers in combination with paclobutrazol

Abstract: In tomatoes production system, etiolation is the main cause of seedlings loss. Some inhibitors, such as paclobutrazol (PBZ), have been used to reduce this problem. This study aimed to evaluate the effect of different doses of paclobutrazol, with and without polymer association, at different degrees of permeability, on the physiological quality of seeds. Seeds of two tomato cultivars, Ozone and Paronset, were treated with four concentrations of paclobutrazol (0, 0.004, 0.008 and 0.016 g mL a.i.10 g seeds-1), and combined with three fixatives (water, P1 and P2). After the treatments, germination test, germination speed index test and cold test were carried out, and after five months of seed storage, the analyzes were repeated. The increase in PBZ dose reduces both germination percentage and germination speed index. After storage, the product acts differently on seed germination. The synthetic polymers, in the dose used in this study, are effective in PBZ fixation on the seeds coat, but do not reduce the harmful effect of PBZ on seed germination.

摘要：在番茄生产体系中，幼苗黄化是导致种苗损失的主要原因。诸如多效唑（paclobutrazol，PBZ）这类生长抑制剂已被用于缓解该问题。本研究旨在评估不同剂量的多效唑，分别搭配或不搭配不同渗透性能聚合物载体时，对种子生理品质的影响。试验选用两个番茄品种‘Ozone’与‘Paronset’的种子，以四种浓度的多效唑（0、0.004、0.008和0.016 g 有效成分·mL⁻¹，每10克种子）进行处理，并分别搭配三种固着剂（水、P1、P2）。处理完成后，依次开展发芽试验、发芽速率指数测定以及低温发芽试验；并在种子贮藏五个月后，重复上述各项测定。结果显示，多效唑剂量的提升会同时降低种子发芽率与发芽速率指数。种子贮藏后，该药剂对种子发芽的作用效果出现变化。本研究所用剂量的合成聚合物，可有效将多效唑固着于种皮表面，但无法缓解多效唑对种子发芽产生的不利影响。