Effect of cypermethrin insecticide on root chromosome morphometry of scallion (Allium fistulosum)

Abstract. Haq FAN, Etikawati N, Solichatun. 2023. Effect of cypermethrin insecticide on root chromosome morphometry of scallion (Allium fistulosum). Cell Biol Dev 7: 14-21. Farmers in Tawangmangu, Karanganyar, Central Java, Indonesia, commonly use a pesticide known as cypermethrin insecticide whenever growing scallion (Allium fistulosum L.). If used at excessive levels, cypermethrin pesticide can be fatal to plants. Chromosome morphological changes are an indicator of cypermethrin insecticide's toxicity. Chromosomal morphometry, the study of chromosomal size and shape, can provide an overall picture of the quality of a plant's development. This research aimed to evaluate cypermethrin insecticide's impact on A. fistulosum root chromosomal morphometrics. Information gleaned from chromosomal morphometry includes chromosome shape, chromosome size, aberration type, chromosomal aberration index, relative asymmetry index, relative centromere index, and mitotic chromosome index. The concentration of cypermethrin was the sole independent variable in this study, which used a Completely Randomized Design (CRD) factorial arrangement. Long green onions were treated with varying concentrations of cypermethrin for up to four weeks: 0 mg/L, 0.05 mg/L, 0.10 mg/L, 0.15 mg/L, 0.20 mg/L, and 0.25 mg/L. The squash method was used to prepare the plant's apex roots. The root chromosomal visualization output was subjected to quantitative and qualitative descriptive analysis. The mitotic index decreased, and the chromosome aberration index increased after exposure to cypermethrin pesticides. The higher the concentration of the pesticide cypermethrin, the lower the mitotic index and the greater the chromosome aberration index. Long green onion root cells exposed to cypermethrin insecticide underwent chromosomal aberrations that could be identified qualitatively. Sticky chromosomes, chromosome bridge, chromosome agglutination, disrupted metaphase, disturbed anaphase, and hypoploid cell are examples of chromosomal aberrations.