An optimum planting density must be employed to get a high yield , depending upon soil condition , varietal tillering ability , fertilizer level , number of plants per hill , and planting season 获得高产必须采用最适植株密度，视土壤条件、品种分蘖力、肥力水平、每蔸苗数和播种季节而定。
2.
Data in table 5 show that although rice yield slightly increased with increasing plant density , the difference between densities was not significant , it indicated that in the case of high level fertilization , 300 , 000 to 375 , 000 hills per ha is enough for getting potential high yield 表5中数据表明，虽然提高植株密度少量增加水稻产量，但密度间差异不显著，这表明在高施肥量的情况下， 30万和37 . 5万蔸/公顷对获得高产潜势来说已很满足。
3.
In planting ratoon sugarcane , " four early " : ploughing soil so as to loose sugarcane sprout , applying fertilizer during seedling so as to provide necessary nutrition for growing early and rapidly , early thinning out and singling seedling with shelling sear leaves so as to insure available populations and ventilation , controlling diseases and pests so as to ensure sugarcane seedling orderly , full and healthy 宿根蔗突出“四早”管理，即早破垄松蔸，促进蔗蔸萌发；早施苗肥，促进蔗苗早生快发，保证养分有效供给；早间苗、定苗，及时剥除枯脚叶，确保甘蔗有效群体和田间通透性；早防治病虫，保证苗齐、苗全、苗匀、苗壮。
