Produksi protein dan antosianin pucuk kolesom (Talinum triangulare (Jacq.) Willd) dengan pemupukan nitrogen+kalium dan interval panen

Abstract

The research was conducted in Leuwikopo, Dramaga, Bogor, Indonesia from November 2009 until December 2010 to increase waterleaf shoot protein and anthocyanin production with nitrogen+potassium application and harvest interval. The research consisted of 4 experiments. The first experiment was conducted from November 2009 until Februari 2010 to study the effect of different levels of nitrogen+potassium and harvest interval on waterleaf shoot protein and anthocyanin production. The result showed that combination of 100 kg urea/ha + 100 kg KCl/ha and 15 days harvest interval gave the highest protein production (4.72 g/plant). The highest anthocyanin production was resulted by treatments of 100 kg urea+ 100 kg KCl/ha (152.23 μmol/plant) and 10 days harvest interval (165.27μmol/plant), but it was not influenced by interaction between level of N+K fertilizer and harvest interval. The second experiment was conducted from April until July 2010 to study the effect of different harvest intervals and splitting application of nitrogen+potassium on waterleaf shoot protein and anthocyanin production. The result showed that combination of 15 days harvest interval and three times fertilization with total dosages of 150 kg urea+ 150 kg KCl/ha produced the highest protein production (13.90 g/plant) and anthocyanin (250.61 μmol/plant) of marketable shoots. The third experiment was conducted from April until July 2010 to study the effect of foliar application of nitrogen+potassium and harvest interval on waterleaf shoot. The result showed that 4 times of foliar application and 100 kg urea + 100 kg KCl/ha of basal fertilizer produced the highest shoot protein (5.69 g/plant) and anthocyanin production (109.44 μmol/plant) on the waterleaf which harvested every 15 days interval. The fourth experiment was conducted from October until December 2010 to study the effect of soil and foliar applications of nitrogen+potassium fertilizer on waterleaf shoot protein and anthocyanin production. The result showed that the highest protein and anthocyanin production of waterleaf shoot for 75 days were produced by 100% soil application of N+K; protein production was 16.98 g/plant while anthocyanin production was 170.27μmol/plant. From those 4 experiments, it can be concluded that to obtain the highest protein and anthocyanin production, waterleaf must be harvested every 15 days from 30 until 75 days after planting. Furthermore, waterleaf must be fertilized in three steps with 100 kg urea + 100 kg KCl/ha at planting, 25 kg urea + 25 kg KCl/ha at 30 and 60 days after planting. The correlation between protein or anthocyanin content with the growth and other physiologis components were not consistent.

Kolesom merupakan sayuran bergizi berkhasiat obat karena mengandung protein dan antosianin pada pucuknya. Peningkatan kualitas pucuk kolesom melalui teknik budidaya pertanian harus dilakukan sebagai langkah untuk menyusun panduan praktek budidaya yang baik (Good Agriculture Practices/GAP) sayuran kolesom yang dapat diterapkan oleh masyarakat luas. Penelitian untuk meningkatkan produksi protein dan antosianin pucuk kolesom dengan pemupukan nitrogen+kalium dan interval panen telah dilakukan di kebun percobaan IPB, Leuwikopo, Bogor. Percobaan pertama untuk mempelajari pengaruh berbagai dosis pupuk nitrogen+kalium dan interval panen terhadap produksi protein dan antosianin pucuk kolesom telah dilaksanakan pada bulan November 2009 sampai Februari 2010. Percobaan menggunakan rancangan acak kelompok lengkap dengan 2 faktor dan 3 ulangan. Dua faktor tersebut adalah dosis pupuk N+K (50 kg urea + 50 kg KCl/ha, 50 kg urea + 100 kg KCl/ha, 100 kg urea + 50 kg KCl/ha, 100 kg urea + 100 kg KCl/ha) dan interval panen (30, 15, dan 10 hari). Hasil penelitian menunjukkan bahwa dosis pupuk 100 kg urea + 100 kg KCl/ha dan interval panen 15 hari memberikan produksi protein pucuk kolesom tertinggi yaitu sebesar 4.72 g/tanaman. Produksi antosianin pucuk kolesom tertinggi dihasilkan oleh masing-masing perlakuan 100 kg urea+ 100 kg KCl/ha (152.23 μmol/tanaman) atau interval panen 10 hari (165.27 μmol/tanaman), namun tidak dipengaruhi oleh interaksi antara kedua perlakuan tersebut. Terdapat korelasi positif antara kandungan protein dengan klorofil; kandungan antosianin dengan gula; kandungan antosianin dengan semua komponen pertumbuhan, kecuali bobot kering daun.