Salinas-Hernandez H, Saldamando-Benjumea C I
Facultad de Ciencias, Departamento de Biociencias, Universidad Nacional de Colombia, Medellín, Colombia.
Neotrop Entomol. 2011 Jul-Aug;40(4):421-30.
The fall army worm Spodoptera frugiperda (Smith) is a migratory important pest of corn, sorghum, rice, grass and bermudagrass in North and South America. This species has diverged into two genetically differentiated but morphologically identical strains, "the rice" and "the corn". They have been analyzed by sequencing the genes cytochrome oxydase I, II and ITS1 from populations from the United States and Brazil. However, no such studies were performed in Colombia. In here, we identified 43 haplotypes by sequencing a fragment of the COI gene from 102 individuals, of which 40 had already been identified as the "corn" and "rice" strains or to their hybrids from Tolima, and the rest were collected from corn, cotton, sorghum, grass and rice fields in other regions of Colombia. The corn strain haplotype H1 was the most frequently found in this country, representing the main target for FAW monitoring programs. AMOVA analysis confirmed the population structure between Colombian and North American S. frugiperda haplotypes (F(ST) = 0.76812, P < 0.001), but not within the different Colombian regions, suggesting high gene flow within the country. The ML trees obtained for Tolima and for Colombia as a whole did not generate clustering amongst S. frugiperda sequences, neither via host-plant association nor by geographical areas. The minimum spanning network for Colombia corroborated our finding that the haplotype H1 has the highest frequency in the country. Our data suggest that haplotype frequency determination will be useful in the establishment of a monitoring system for this species.
草地贪夜蛾Spodoptera frugiperda（史密斯）是一种具有迁飞习性的重要害虫，危害南北美洲的玉米、高粱、水稻、牧草和百慕大草。该物种已分化为两个基因不同但形态相同的品系，即“水稻型”和“玉米型”。已通过对来自美国和巴西种群的细胞色素氧化酶I、II和ITS1基因进行测序对它们进行了分析。然而，在哥伦比亚尚未开展此类研究。在此，我们通过对102个个体的细胞色素氧化酶亚基I（COI）基因片段进行测序，鉴定出43种单倍型，其中40种已被鉴定为来自托利马的“玉米型”和“水稻型”品系或其杂交种，其余则是从哥伦比亚其他地区的玉米、棉花、高粱、牧草和稻田中采集的。玉米型单倍型H1在该国最为常见，是草地贪夜蛾监测计划的主要目标。分子方差分析（AMOVA）证实了哥伦比亚和北美草地贪夜蛾单倍型之间的种群结构（F(ST) = 0.76812，P < 0.001），但在哥伦比亚不同地区内部并非如此，这表明该国境内存在较高的基因流。从托利马以及整个哥伦比亚获得的最大似然树（ML树）在草地贪夜蛾序列中未产生聚类，无论是通过寄主植物关联还是地理区域。哥伦比亚的最小生成网络证实了我们的发现，即单倍型H1在该国频率最高。我们的数据表明，单倍型频率测定将有助于建立该物种的监测系统。
