机插粳稻分蘖影响因子分析

目的]为提高机插粳稻产量提供参考。方法]以9746（武运粳7号）为材料,设置不同的栽插深度、管水条件、施肥及基本苗数,进行栽插深度、管水条件、施肥及基本苗数对机插粳稻分蘖的影响试验。结果]栽插深度应控制为＂叶不见土＂。即第2片真叶叶耳不接触实土土面,在3 cm以内,最适宜的插深为0～1.5 cm,不宜超过3.0 cm。应根据机插粳稻分蘖发生的特点,栽后3 d,晴天浅水活棵,阴天不上水;栽后15 d内干湿交替;15～25 d是低位分蘖盛期,浅水间隙灌溉;25 d后多次轻搁田。应根据机插粳稻中小苗移栽、机械植伤相对较重,生根稍缓等特点,基肥以复合肥为主,占总N量20%～30%,分蘖肥分3次轻施,以N肥为主,第3次视苗色和长势确定用复合肥或N肥,以利稻株C∶N协调,保证拔节正常。基本苗应确定为3～5苗。应根据机插粳稻育秧质量（均匀度和成秧率）确定取秧量。单位面积穴数应以24～27万穴/hm2为宜（即株距11.7～13.1 cm）。结论]确定了机插粳稻适宜的栽插深度、管水条件、施肥及基本苗数。

Analysis of the Impact Factors on Tillering of Machine Transplanted Japonica Rice

Objective]To provide references for improving the yield of machine transplanted japonica rice.Method] With 9746(Wuyunjing No.7) as material,a field test was carried out by setting different transplanting depths,irrigation conditions,fertilizer application and number of basic seedlings to analyze their impact on tillering of machine transplanted japonica rice.Result]The optimal transplanting depth was 0-1.5 cm without exceeding 3.0 cm.3 d after transplanting,the japonica rice should be watered on sunny day,no watering on cloudy day,alternate drying and wetting after 15 d,slight intermittent irrigation at 15-25 d,slight field draining after 25 d.Compound fertilizer was applied as base fertilizer,accounting for 20%-30% of total N amount,tillering fertilizer was applied in three separate times,the first two was N fertilization,while at the third time compound fertilizer or N fertilizer was decided according to the color and growth of the seedlings so as to make sure the balance between C and N and ensure normal jointing.The number of basic seedlings was decided based on the quality of seedling(evenness and survival rate).The optimal number of holes per unit area was 240 000～270 000 hole/hm2 with the plant spacing of 11.7-13.1 cm.Conclusion]The transplanting depth,water conditions,fertilization and number of basic seedlings of japonica rice were decided.