Pengaruh Pemupukan terhadap Pertumbuhan, Hasil dan Kualitas Biji Empat Klon Kopi Robusta di Tanah Podsolik Merah Kuning, Lampung Utar

Abstract

R ecommendation of Robusta coffee fertilizer that available until now is only in general. In fact, the type and amount of fertilizer needed is highly dependent on environmental conditions, clones, and plant age. The study aim ed to investigate the effect of combination doses of urea, SP36, and KCl fertilizer on growth , yield, and bean quality of four Robusta coffee clones cultivated in red - yellow podzolic soil type (PMK), North Lampung. The study was conducted at KP. Cahaya Negeri, North Lampung, with the altitude of 250 m above sea level, PMK soil type and climate type of C (Oldeman d ), from October 2011 to June 2014. Th e research was arranged in split plot design with four replications. The main plot was four Robusta coffee clones i.e. (K 1 ) = BP 42; ( K 2 ) = BP 4 0 9; ( K 3 ) = BP 936; and ( K 4 ) = BP 939, while the s ub plot was four combination doses of u rea , SP36 , and KCl i.e. (P 1 ) = 30:20:20 g/tree; ( P 2 ) = 40:30:30 g/tree; ( P 3 ) = 50:40:40 g / tree; and ( P 4 ) = 60:50:50 g/tree. The results showed that four Robusta coffee clones (BP 42, BP 409, BP 936, and BP 939) cultivated in PMK soil type, KP. Cahaya Negeri, North Lampung, had the same response to combination doses of urea, SP36 and KC l fertilizer . The combination doses of urea, SP36 , and KCl of 5 0, 4 0, and 4 0 g/tree , respectively were optimal and efficient for growth and yield of those four clone s until 2.5 years old . However, the dose has not yet been able to improve the quality of coffee beans.