世界各国种子园设计类型、特点及发展情况如下: (一)纯行式设计:有些早期的种子园将每个无性系单纯种植成行,今日也偶有采用。这种设计的缺点是增加了自交的危险性,而且以后除掉不理想的无性系后,显然间距极不均匀。(二)棋盘式设计:双无性系种子园可按行或株交错安排两个经过选择的无性系。(三)完全随机排列设计:将全部无性系的所有分枝植株按种植位置完全随机排列,这是一种最简单的设计。然而,这种设计会给种植或大田嫁接带来困难,也会给后期确定每个分枝植株的位置带来困难。如果同瑞典一样采取隔行或隔株的系统疏伐,分别随机保留或伐除无性系,就能使设计更为精确。这种方法曾在澳大利亚、加拿大、尼日利亚、南非、瑞典及美国等国得到推广使用。苏联曾一度采取嫁 The design, characteristics and development of seed orchards in various countries in the world are as follows: (1) Pure Line Design: Some early seed orchards will be planted simply for each clones and are occasionally used today. The disadvantage of this design is that it increases the risk of selfing and, after removing undesired clones in the future, it is clear that the spacing is very uneven. (B) checkerboard design: Double clonal seed orchard can be staggered rows or staggered arrangement of two selected clones. (C) completely random design: all the clones of all clones by planting location completely random arrangement, this is one of the most simple design. However, this design can create difficulties for grafting or field grafting, as well as for later identification of the location of each branched plant. If we adopt the same system of interlacing or isolation as in Sweden, we can make the design more accurate if we keep or remove the clones randomly. This method has been used in Australia, Canada, Nigeria, South Africa, Sweden and the United States. The Soviet Union once took marriages