据《新科学家》杂志近期报道,加拿大生物学家认为,对针叶植物进行辅助授粉（或IVF技术,即试管受精技术）可能是森林业发展的下一个重大事件。这种技术通过克服树种间的障碍能培养出新的杂交针叶树种。 但一些针叶树种能杂交,另一些则不能,尽管他们有类似的染色体并从理论上说能产生出有活力的后代。这些树种不能杂交的主要障碍是在于一种叫做珠心的结构,珠心是一层组织,花粉必须通过它将一条长管伸到雌配子体。但办有同种可通过珠心生长,而异种花粉通常都被拒绝接受。 According to a recent report by New Scientist, Canadian biologists believe that secondary pollination of conifers (or IVF technology, IVF) may be the next major event in the development of the forest industry. This technique can breed new hybrid conifers by overcoming the barriers between species. But some conifers can hybridize, while others can not, though they have similar chromosomes and theoretically produce viable offspring. The main obstacle that these species can not hybridize to is a structure called a bead, whose core is a layer of tissue through which pollen must extend to a female gametophyte. But do have the same kind of growth through the beads, and heterogeneous pollen are usually rejected.