Ukuran Kepala Larva, Pupa, dan Imago serta Karakter Tubuh Larva Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) di Kabupaten Bogor

Abstract

Ulat grayak frugiperda atau Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) merupakan serangga invasif yang dapat menyerang banyak famili tanaman, salah satunya adalah famili gramineae seperti jagung, padi, gandum, sorgum, dan tebu. Larva S. frugiperda dapat menyebabkan kerusakan parah dan dapat mengakibatkan kematian tanaman. Larva ini memiliki variasi morfologi tubuh sehingga dapat menyulitkan identifikasi instar larva dalam kegiatan monitoring dan pengendalian hama ini di lapangan. Penelitian ini bertujuan mengelompokkan ukuran lebar kapsul kepala larva, melakukan pengukuran panjang dan lebar pupa, serta rentang sayap imago. Penelitian ini juga mengamati variasi warna tubuh, warna dan corak kepala, warna garis huruf Y, warna garis dorsal dan warna garis lateral dari larva S. frugiperda yang diperoleh dari Kabupaten Bogor. Sampel larva yang diambil secara purposive sampling diperoleh dari 3 kecamatan di Kabupaten Bogor, yaitu Ciomas, Cikarawang, dan Cibeureum. Pengamatan terhadap morfologi dan pengukuran lebar kapsul kepala larva dilakukan menggunakan mikroskop stereo. Data lebar kapsul kepala larva dianalisis dengan boxplot. Untuk data warna tubuh, corak dan warna kepala, warna huruf Y, warna garis dorsal, serta warna garis lateral dianalisis secara deskriptif. Lebar kepala kapsul larva instar 1, 2, 3, 4, 5, dan 6 berturut-turut berkisar pada 0.32- 0.46 mm, 0.55-0.70 mm, 0.72-0.99 mm, 1.01-1.66 mm, 1.71-2.29 mm, dan 2.30- 3.25 mm. Warna tubuh, warna dan corak kepala, warna huruf Y, warna garis dorsal, dan warna garis lateral berturut-turut sebanyak 3 variasi, 6 variasi, 4 variasi, 6 variasi, dan 4 variasi. Panjang pupa, lebar pupa, panjang sayap depan, panjang sayap belakang, dan rentang sayap imago jantan tidak berbeda nyata dengan imago betina.

The fall armyworm or Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) is an invasive insect that can attack many plant families, one of which is the Gramineae family such as corn, rice, wheat, sorghum, and sugar cane. S. frugiperda larvae can cause severe damage and can result in plant death. These larvae have variations in body morphology so that it can be difficult to identify larval instars in monitoring and controlling these pests in the field. This study was aimed to classify the width of the larval head capsule, to measure the length and width of the pupa, and the wingspan of the adult. This study also observed variations in body colour, head colour and pattern, letter Y line colour, dorsal line colour and lateral line colour of S. frugiperda obtained from Bogor Regency. The sample of larvae taken by purposive sampling was obtained from 3 subdistricts namely from Ciomas, Cikarawang, and Cibeureum. Observations of the morphology and measurement of the larval head capsule width were carried out using a stereomicroscope. The data on the width of the larval head capsule was analyzed by a boxplot. Data for the body colour, head pattern and colour, letter Y colour, dorsal line colour, and lateral line colour were analyzed descriptively. The head width of instar larvae capsules 1, 2, 3, 4, 5, and 6 ranged from 0.32-0.46 mm, 0.55-0.70 mm, 0.72-0.99 mm, 1.01-1.66 mm, 1.71-2.29 mm, and 2.30-3.25 mm, respectively. The body colour, head colour and pattern, letter Y colour, dorsal line colour, and lateral line colour had 3 variations, 6 variations, 4 variations, 6 variations, and 4 variations, respectively. The length of the pupa, the width of the pupa, The length of the front wings, the length of the hind wings, and the wingspan of the male adult were not significantly different from the female adult.