Effect of Dosage and Application Frequencies of Trichoderma Biofungicide on Rigidoporus microporus Infection in Rubber

Abstract
Description
Biological agents Trichoderma virens and T. amazonicum have been developed and examined for their effectiveness through in vitro and in vivo approaches against Rigidoporus microporus, the cause of white root disease (WRD) in rubber. The effectiveness of these bio-agents can be determined by testing the dosage and frequency of Trichoderma spp. biofungicide application. The research aimed to investigate the effective dose and application frequency of Trichoderma spp. biofungicide on R. microporus infection in rubber seedling. The experiment was conducted in laboratory and screen house of Indonesian Industrial and Beverage Crops Research Institute (IIBCRI), Sukabumi, from June to December 2014. A randomized block design was used with 14 treatments and 3 replications, i.e biofungicide combination (T. virens and T. amazonicum), dosage (25, 50, and 75 g), application frequencies (1 and 2 times application), and two controls (positive and negative). Rubber seedlings used were propellegitiem seeds of GT1 clone planted in polybags. Trichoderma spp. was multiplied using fermentation method in liquid medium, whereas biofungicide was formulated using talc as carrier. Observed variables including Trichoderma spp. population number, incubation period, attack intensity, and WRD attack suppression. The results showed that T. virens and T. amazonicum biofungicides with 50 g/plant dose at one application was the most effective and efficient in suppressing R. microporus development on rubber seedlings. The type, dosage, and frequencies of application increased Trichoderma spp. population in soil, prolonged the pathogen’s incubation period, decreased WRD attack intensity, and suppress the attack of WRD disease.
Agens hayati Trichoderma virens dan T. amazonicum sedang dikembangkan dan telah diuji keefektifannya secara in vitro dan in vivo terhadap Rigidoporus microporus penyebab penyakit jamur akar putih (JAP) pada tanaman karet. Peningkatan keefektifan agens hayati tersebut dapat diketahui melalui pengujian dosis dan frekuensi aplikasi. Tujuan penelitian adalah menentukan dosis dan frekuensi aplikasi biofungisida Trichoderma spp. yang efektif dalam menekan infeksi R. microporus pada benih karet. Penelitian dilaksanakan di laboratorium dan rumah kasa Balai Penelitian Tanaman Industri dan Penyegar (Balittri), Sukabumi, mulai bulan Juni sampai Desember 2014. Percobaan menggunakan rancangan acak kelompok dengan 14 perlakuan, yaitu kombinasi antara jenis biofungisida (T. virens dan T. amazonicum), dosis (25, 50, dan 75 g), frekuensi aplikasi (1 dan 2 kali), pembanding positif (biofungisida komersial), dan pembanding negatif (tanpa biofungisida), masing-masing diulang 3 kali. Benih tanaman karet dalam polybag yang digunakan berasal dari biji propelegitim klon GT 1. Perbanyakan Trichoderma spp. menggunakan metode fermentasi pada media cair, sedangkan formulasi biofungisida menggunakan bahan pembawa talk. Pengamatan meliputi  populasi Trichoderma spp., masa inkubasi, intensitas penyakit, dan penekanan serangan JAP. Hasil penelitian menunjukkan bahwa biofungisida berbahan aktif T. virens dan T. amazonicum dengan dosis 50 g/tanaman satu kali aplikasi cukup efektif dalam menekan perkembangan infeksi R. microporus pada benih karet. Kombinasi antara jenis biofungisida, dosis, dan frekuensi aplikasi, terbukti meningkatkan populasi Trichoderma spp. dalam tanah, memperlambat masa inkubasi patogen, menurunkan intensitas penyakit JAP, dan dapat menekan serangan penyakit JAP.
Keywords
Application frequency; biofungicide; dosage; Trichoderma; white root disease, , Biofungisida; dosis; frekuensi aplikasi; jamur akar putih; Trichoderma,
Citation