Identification of Root Knot Nematode Species, the Pathogen of Branched Tuber Disease on Carrot (Daucus carota L.) in Semarang and Magelang Districts, Central Java

Abstract

Root knot nematode (Meloidogyne spp.) is a pathogen causing branched tuber disease on carrot. The objective of this study was to determine the presence and to identify the species of root knot nematode (Meloidogyne spp.) on carrot plantation in the area of Semarang and Magelang districts. Sampel of infected tuber were taken from three locations with defferent elevation ranges, that were 1200-1400 m, 1400-1600 m, and >1600 m asl. The common symptoms of Meloidogyne spp. in the field were malformation of the tubers such as branched tuber, broken tuber, shortened round tuber, and hairy roots. The disease incidence levels were 52% , 63%, and 67% at location 1, 2, and 3, respectively. The identification of Meloidogyne species was based on female perineal pattern and PCR. Spesific primers were used for M. incognita, M. javanica, and M. arenaria, while multiplex primers were used for mixed species of M. hapla, M. chitwoodi, and M. fallax. Four major root knot nematode species, namely M. incognita, M. javanica, M. arenaria, and M. hapla were succesfully identified from all locations investigated.

Meloidogyne spp. merupakan patogen penyebab penyakit umbi bercabang pada wortel. Penelitian dilaksanakan untuk mengetahui keberadaan dan mengidentifikasi spesies nematoda puru akar (Meloidogyne spp.) pada sentra pertanaman wortel di wilayah Kabupaten Semarang dan Magelang. Sampel wortel sakit diambil dari tiga lokasi, yaitu ketinggian 1200-1400 m dpl, 1400-1600 m dpl, dan > 1600 m dpl. Gejala penyakit Meloidogyne spp. di lapangan umumnya berupa malformasi pada umbi seperti umbi bercabang, umbi pecah, umbi bulat memendek, dan umbi berambut (hairy root). Tingkat kejadian penyakit sebesar 52%, 63%, dan 67% pada lokasi 1, 2, dan 3. Identifikasi spesies Meloidogyne spp. dilakukan dengan morfologi pola perineal nematoda betina dan PCR. Primer spesifik digunakan untuk mendeteksi M. incognita, M. javanica, dan M. arenaria, sedangkan primer multipleks digunakan untuk mendeteksi M. hapla, M. chitwoodi, dan M. fallax. Empat spesies utama nematoda puru akar, yaitu M. incognita, M. javanica, M. arenaria, dan M. hapla berhasil diidentifikasi dari seluruh lokasi yang diteliti.