生产棉花杂交种子的方法很多 ,有三系法、二系法 ,化学杀雄、人工制种等 ,上述方法各有所长 ,又各有其不完善之处 ,目前以人工制种和二系法应用较多。但无论采用何种方法 ,其制种田的产量构成均可用下式表示 :制种田产种量 (kg· hm-2 )　 =每公顷株数×单株结铃数×铃重1 0 0 There are many ways to produce hybrid cotton seeds, there are three lines of law, the second line, chemical kill male, artificial seed production, the above methods have their own strengths, but also have their imperfections, the current artificial seeding and two lines Apply more. However, no matter which method is adopted, the composition of the production of its farming system can be expressed as follows: Production system (kg · hm-2) = number of plants per hectare × number of bolls per plant × boll weight 100