Nymphaea mexicana Zuccarini (Nympheaceae) (Mexican waterlily) is a rooted floating-leaved aquatic plant native to southern USA and Mexico that has become a problematic invasive alien plant in South Africa. Biological control is considered a desirable management strategy for the plant in South Africa. A good understanding of the genetic structure of invasive populations has been useful in other biological control programmes because taxonomic uncertainty about the target plant can result in natural enemies that are not adapted to the invasive populations being considered as potential agents. For N. mexicana, hybrids exist in the wild and horticultural trade, but identification is difficult, so understanding the genetic structure of populations is required to ensure that potential agents are collected off plants similar to invasive populations in South Africa. ISSR (inter-simple sequence repeats) analysis was used to determine whether invasive N. mexicana populations from South Africa were genetically similar to native range populations from USA or whether they were hybrids. Results from these analyses were matched with the morphotypes of each population based on petal colour, shape, and size. The genotypes suggested by the ISSR analyses corroborated the presence of both hybrid and pure forms of N. mexicana in South Africa. Populations of N. mexicana in the invaded range that are genetically similar to native range populations are more likely to be suitable for biological control, while other populations are likely to be hybrids formed by crossing of parents from the native range or within the horticultural trade, which may present difficulties for management using biocontrol.

睡莲（Nymphaea mexicana Zuccarini）（睡莲科）（墨西哥睡莲）是一种有根的浮叶水生植物，原产于美国南部和墨西哥，现已成为南非一个有问题的外来入侵植物。对于南非的工厂而言，生物控制被认为是理想的管理策略。对入侵种群遗传结构的深入了解在其他生物控制程序中很有用，因为有关目标植物的分类学不确定性可能导致不适合入侵种群的天敌被视为潜在病原体。对于墨西哥墨西哥猪笼草野生和园艺贸易中都存在杂种，但是鉴定很困难，因此需要了解种群的遗传结构，以确保从类似于南非入侵种群的植物中收集到潜在的病原体。ISSR（简单序列间重复）分析用于确定来自南非的墨西哥侵袭性猪笼草种群在遗传上是否类似于美国的本地种群或它们是否是杂种。这些分析的结果根据花瓣的颜色，形状和大小与每个种群的形态型相匹配。ISSR分析所建议的基因型证实了墨西哥猪笼草杂种和纯种形式的存在。墨西哥猪笼草的种群 在入侵范围内，遗传上与本地范围相似的种群更可能适合进行生物防治，而其他种群很可能是由父母从本地范围或园艺贸易中杂交而形成的杂种，这可能给他们带来困难。使用生物防治进行管理。