Aplikasi Biochar Limbah Ekstraksi Bromelin Diperkaya N dan K pada Ultisol: Pertumbuhan Vegetatif dan Kadar Hara Daun Nanas

Abstract

Pemupukan anorganik secara intensif dan pertanaman nanas monokultur dalam 40 tahun terakhir telah menyebabkan degradasi kesuburan tanah di lahan perkebunan PT. Great Giant Pineapple (GGP). Permasalahan lainnya adalah tingginya tingkat kehilangan hara serta rendahnya efisiensi pemupukan dan penyerapan hara oleh tanaman. Biochar limbah ekstraksi bromelin (LEB) memiliki residence time dalam tanah lebih lama daripada amelioran organik lainnya. Penelitian ini bertujuan mengevaluasi pengaruh aplikasi biochar LEB diperkaya N dan K (biochar LEB NK) sebagai pupuk lepas terkendali terhadap pertumbuhan vegetatif dan kadar hara daun nanas pada 3 bulan setelah tanam (BST) di Ultisol lahan perkebunan PT. GGP. Percobaan dilakukan dengan RAK perlakuan tunggal 4 taraf, yaitu aplikasi biochar LEB NK dengan dosis 0%, 50%, 100%, dan 150% dosis standar dengan 4 ulangan. Perlakuan diaplikasikan sebelum tanam dan pupuk dasar yang digunakan meliputi masing-masing 100 kg/ha K2SO4, DAP, dan Kieserite. Hasil penelitian menunjukkan bahwa hingga 3 BST pertumbuhan vegetatif nanas cenderung meningkat, namun kadar hara N, P, dan K daun cenderung menurun dengan peningkatan taraf perlakuan.

Intensive inorganic-fertilizers application and monoculture cultivation of pineapple during the last 40 years have caused soil fertility degradation in the plantation land of PT Great Giant Pineapple (GGP). Other problems faced are high nutrient loss and low efficiency of fertilization and nutrient absorption by plants. Bromelain extraction waste (BEW)-derived biochar has a longer residence time in soil than other organic ameliorants. This research aims to evaluate the effect of application of BEW-biochar enriched with N and K (BEW-biochar NK) as a controlled release fertilizer on vegetative growth and leaf nutrient concentration of pineapple at 3 months after planting (MAP) on Ultisol of plantation land of PT. GGP. The research was carried out according to RBD single treatment with 4 levels, namely the application of BEW biochar NK at 0%, 50%, 100%, and 150% of the standard dose with 4 replications. The treatment was applied before planting and the basic fertilizers, including 100 kg/ha of K2SO4, DAP, and Kieserite, respectively. The results showed that until 3 MAP, the pineapple vegetative growth tended to increase, but leaf N, P and K nutrient concentration tended to decrease with the treatment application level.