Ekspresi morfologi tiga jenis jeruk sebagai indikator ketahanan terhadap serangan Polyphagotarsonemus latus (Banks) (Acari: Tarsonemidae)

Abstract

Salah satu hama penting benih tanaman jeruk adalah tungau perak jeruk (TPJ) Polyphagotarsonemus latus (Banks) (Acari: Tarsonemidae). Penelitian ini bertujuan untuk mengkaji pengaruh serangan TPJ terhadap morfologi daun dan tingkat ketahanan tiga jenis jeruk. Tiga jenis jeruk, yaitu Siam, Keprok, Manis digunakan sebagai tanaman uji. Tunas dari ketiga jenis jeruk tersebut diuji kandungan nutrisinya dan dilakukan infestasi TPJ sebanyak 5 individu pada tunas yang berumur lebih kurang 10 hari. Pengamatan populasi TPJ dilakukan 7 hari setelah infestasi (HSI) dan pengamatan selanjutnya dilaksanakan 4 hari sekali. Hasil penelitian menunjukkan kelimpahan TPJ paling rendah pada 23 HSI didapat pada jenis Siam (0,5 ± 0,38 individu) dan Keprok (0,25 ± 0,16 individu). Populasi TPJ meningkat pada 11 sampai 15 HSI, dan mulai menurun pada 19 HSI. Berdasarkan analisis korelasi Pearson, kelimpahan TPJ dipengaruhi oleh kadar lemak dan serat kasar daun. Hasil pengamatan juga menunjukkan bahwa jenis Manis lebih tahan dibandingkan dengan jenis lainnya. Dapat disimpulkan, jenis Manis masih lebih tahan dibandingkan dengan jenis Siam dan Keprok.One of the important pests of citrus seeds is citrus silver mites (CSM) Polyphagotarsonemus latus (Banks) (Acari: Tarsonemidae). This study aimed to examine the effect of CSM attack on leaf morphology and resistance level of three citrus species. Three types of citrus, namely Tangerine, Mandarin, and Sweet Orange were used as test plants. The shoots of the three types of citrus were tested for nutritional content and five CSM individuals were invested on young leaves that were approximately 10 days old. Observations of CSM population were made 7 days after the investment (DAI) and further observations were carried out every 4 days. The results showed that the lowest abundance of TPJ at 23 DAI was found in type of Tangerine (0.5 ± 0.38 individual) and Mandarin (0.25 ± 0.16 individual). The population of CSM increased at 11 to 15 DAI, and began to decline at 19 DAI. Based on the Pearson correlation analysis, the abundance of CSM was influenced by the fat content and crude fiber content of the leaves. Observations also showed that the Sweet type was more resistant than other types. It can be concluded that the Sweet Orange is more resistant than the Tangerine and Mandarin species.