Respon pertumbuhan vegetatif semaian akibat aplikasi mikroba potensial pada rehabilitasi pohon kakao tanpa penebangan
Authors: Palad Marliana S. , Aminah Aminah 
Published: December 2020

Usaha yang dapat dilakukan untuk megatasi penurunan produksi pohon kakao tua dan rusak adalah penerapan inarching grafting atau penyambungan tanaman kakao muda unggul berumur minimal 6 bulan yang ditanam di sekitar pohon tua. Tujuan penelitian ini adalah mengkaji pengaruh aplikasi Trichoderma asperellum dan Azotobacter chroococcum terhadap pertumbuhan vegetatif semaian kakao yang akan disambungkan ke pohon kakao tua menggunakan metode inarching grafting. Penelitian ini menggunakan Rancangan Petak Terbagi dengan tiga ulangan. Petak Utama yaitu aplikasi T.asperellum sebanyak 4 g L-1 setiap tanaman, dengan empat taraf: tanpa T.asperellum (T0), satu kali (T1), dua kali (T2), dan tiga kali (T3) aplikasi. Anak Petak adalah inokulasi A.chroococcum sebanyak 40 ml x 108 cfu setiap tanaman, dengan 3 taraf: tanpa A.chroococcum (A0), satu kali (A1) dan dua kali (A2) aplikasi. Hasil analisis menunjukkan tidak terdapat interaksi antara aplikasi T.asperellum dengan A.chroococcum, tetapi terdapat pengaruh tunggal dari kedua mikroba potensial yang diaplikasikan. Pada umur semaian 90 hst, aplikasi dua kali A.chroococcum menghasilkan rata-rata tinggi tanaman 155,25 cm, total daun 41 helai dan diameter batang 13,10 mm. Pemberian tiga kali T.asperellum menghasilkan rata-rata tinggi tanaman 150,89 cm,  total daun 41,22 helai dan diameter batang 12,86 mm. Semaian yang diberi mikroba potensial digunakan untuk rehabilitasi pohon kakao tua. An efforts that can be done to overcome the decline in production of old and damaged cocoa trees are the application of inarching grafting or grafting of superior young cocoa plants with a minimum age of 6 months planted around old trees. The purpose of this study was to examine the effect of the application of Trichoderma asperellum and Azotobacter chroococcumon the vegetative growth of cocoa seedlings which was grafted to old cocoa trees using the inarching grafting method. The research used a Split Plot Design with three replications. The main plot was application of T.asperellum of 4 g L-1 for each seedling and cocoa tree, consisted of four levels. i.e: without T.asperellum (T0), one time application (T1), two times application (T2), and three times application (T3). The subplot factor was A.chroococcum as much as 40 ml x 108 cfu on each seedling and cocoa tree, consisted of three levels, i.e.: without A. chroococcum (A0), one time application (A1) and two times application (A2).  The analysis of variance results showed that no interaction between applications of T.asperellum  with  A.chroococcum, but it had a singular effect for both potential microbial applied. At 90 days after planting, the application of A.chroococcum twice resulted in an average plant height of 155.25 cm, a total of 41 leaves and a stem diameter of 13.10 mm. Application of T.asperellum three times resulted in an average plant height of 150.89 cm, the number of leaves 41.22 sheets and a stem diameter of 12.86 mm. The seedlings that inoculated with potential microbes can be used for rehabilitation of old cacao trees.