双覆盖技术在三七育苗上的应用效果研究

Double mulching application for Panax notoginseng growing seedlings

目的：研究双覆盖技术在三七育苗上的应用效果，为三七育苗方法的改进和节水灌溉提供理论依据。方法：采用田间随机区组试验设计，对不同覆盖方式处理的土壤含水率、土温及容重进行取样测定，同时调查记录田间三七出苗率、种苗质量。结果：同传统松毛或稻草单覆盖相比，三七育苗床畦面采用松毛或稻草＋地膜的双覆盖方式，可减少育苗初期浇水量2／3以上，松毛或稻草＋地膜的双覆盖方式三七种子播种到出苗的40d内不用浇水，保持出苗期土壤含水量稳定在30％左右和土温稳定在9—16．5℃，促进畦面土壤疏松，防止田间倒春寒危害，从而显著提早三七出苗期，提高田间出苗率、出苗整齐率和种苗质量。仅采用松毛或稻草的单覆盖方式保水、保温效果较差，需12d左右浇施一遍水，三七田间出苗时间较双覆盖处理晚14d，出苗盛期晚24～26d，出苗率低11．3％～18．7％，且松毛的效果要优于稻草。采用地膜单覆盖虽然有较好保水、保温效果，促进三七出苗和提高发芽率，但存在Et均土温变化较大、田间土壤易板结，畦面青苔、杂草较多，不利于后期田间管理的不足。结论：生产上建议三七种子播种期采用松毛＋地膜双覆盖方式，以节水抗旱、节省劳力，提高种子出苗率和种苗质量，出苗盛期后揭掉地膜采用松毛单覆盖的方式进行苗期管护。

Objective： In order to improve the irrigation for Panax notginseng growing seedlings, different mulching ways were carried out to investigate the effects of double mulching. Method ： Field experiment was applied to study soil moisture, soil temperature and bulk density of different mulching ways while the germination rate and seedlings growth also were investigated. Result： Compared with the traditional single mulching with pine leaves or straw, double mulching using plastic film combined with pine leaves or straw could reduce 2/3 volumes of irrigation at the early seedling time Double mulching treatments didn＇t need to irrigate for 40 days from seeding to germination, and kept soil moisture and temperature steady at whole seedling time about 30% and 9.0-16.6 ℃, respectively. The steady soil moisture and temperature benefited to resist late spring cold and germinate earlier while kept germination regularly, higher rate and seedlings quality. In contrast, single mulching using pine leaves or straw had poor soil moisture and temperature preserving, needed to irrigate every 12-day, meanwhile dropped the germination and booming time 14 days and 24-26 days, respectively, reduced germination rate about 11.3%-8.7%. However, single pine leaves mulching was better than straw mulching. In addition, though better effects of soil moisture and temperature preserving as well as earlier and higher rate of germination with single plastic films mulching had, some disadvantages had also been observed, such as daily soil temperature changed greatly, seedling bed soil hardened easily, more moss and weeds resulted difficulty in later management. Conclusion： To the purpose of saving water and labor as well as getting higher germination rate and seedlings quality, double mulching using plastic films combined pine leaves at the early time and single mulching removing plastic films at the later time is suggested to apply in the growing seedlings of P. notoginseng.