根据水稻旱直播同步施肥播种的农艺要求,研制了一种同步开沟起垄施肥水稻精量旱穴直播机,可同步完成开沟、起垄、施肥、覆盖和播种作业。该机器在2BDH-8型水稻精量旱穴直播机上增加施肥装置改装而成,根据水稻旱穴直播施肥农艺要求设计了排肥动力传动系统、排肥系统和施肥开沟器,排种、排肥动力均来自于拖拉机;采用锐角式施肥沟开沟器,在距种沟水平距离100~120mm处开出宽50mm、深50~70mm的施肥沟;采用外槽轮式排肥器将肥料排入施肥沟底,施肥后由播种机拖板刮土覆盖施肥沟。生产试验结果表明,机械定位深施肥的节肥增产效果明显,同等施肥量条件下,机械施肥播种处理与人工施肥播种处理相比,水稻分蘖能力平均增加6.9穗/蔸,增幅25.2%;相对叶绿素含量(SPAD值)平均增加8.9,增幅29.8%;氮素利用效率绝对值提高13.78%,增幅22.3%;氮素偏生产力每千克氮提高20.54kg,增幅46.3%;产量增加1411.5kg/hm2,增幅29.5%。同步开沟起垄施肥水稻精量旱直播机能同时完成开沟、起垄、施肥、覆盖和播种作业,且与人工施肥播种相比增产显著,研究结果可为指导水稻旱直播定位深施肥节氮栽培提供理论依据。
According to the agronomic requirements of rice direct seeding technique with synchronous fertilizing, a precision rice hill-drop drilling machine for dry land with opening furrows, forming ridges, applying fertilizer, covering and seeding synchronously was developed. A fertilizing device was added to the 2BDH-8 type rice hill-drop drilling machine developed in South China Agricultural University. The power transmission system, fertilizing system and furrow opener were designed. The seeding and fertilizing system was both powered by the tractor engine to ensure the synchronization of seeding and fertilizing. An acute angle furrow opener was designed to open furrows with 50 mm wide, 50-70 mm deep and 100-120 mm away from seeding furrows. Fertilizers were applied into the bottom of the furrows through an external slot wheeled feeder and then covered with soil. Experimental results showed that the synchronous deep fertilizing could increase the production efficiency signJificantly than the manual fertilizing. With the same fertilizing level, compared with artificial fertilization seeding, synchronous fertilizing improved the rice tillering by an average of 6.9 spikes per individual plant with an increase of 25.2%, increased the average SPAD value by 8.9 with 29.8%, improved nitrogen use efficiency by 13.78% with 22.3%, improved partial productivity of nitrogen by 20.54 kg/kg.N with an increase of 46.3%, and increased rice yield by 1411.5 kg/hm2 with an improvement of 29.5%.The results showed that this machine can complete opening furrows, forming ridges, applying fertilizer, covering and seeding synchronously, and the yield increased significantly than the manual fertilizing. The experimental results can provide a theoretical basis of nitrogen saving cultivation for guiding the rice hill-drop drilling machine in dry land with deep fertilization.