Genetic analysis and molecular phylogeny of rice green leafhopper Nephotettix nigropictus (Stal) based on the mitochondrial COI DNA gene

The green leafhopper Nephotettix nigropictus (Stål) (Auchenorhyncha: Hemiptera) is insect transmitter of rice tungro virus that cause damage and death on rice plants. There is none genetic analysis of N. nigropictus that be isolated from Samosir island-North Sumatra Indonesia by using partial DNA sequence of mitochondrial citochrome oxidase sub unit I (COI) DNA gene. This study aimed to identify and to know the nucleotide composition of N. nigropictus based on mt COI or DNA barcoding. Genetic analysis of that leafhopper consisted of four steps, namely: Leafhopper sample catching on rice field by using insect net, DNA extraction by using Zymo Tissue & Insect DNA Mini Prep, DNA amplification by using PCR and My TaqTM HS Red Mix and DNA sequence analysis by using ABI PISM 3730XL Genetic Analyzer. Primer cocktail tRWF-Mlep was used in DNA amplification step. The research result showed that mt COI DNA fragment of N.nigropictus has length 448-458 bp. This mt COI DNA sequence was dominated by A and T bases (74.5%). The concentration of T, C, A and G nucleotides in the COI sequence were 38.60%, 13.10%, 35.80% and 12.40%, respectively. Identification of N.nigropictus based on this mt COI DNA sequence confirmed the identification result based on its morphological characters.