TY - GEN CY - UNIVERSITAS LAMPUNG ID - eprints13939 UR - http://digilib.unila.ac.id/13939/ A1 - Dharma Agista Pratama, 1114071013 Y1 - 2015/10/12/ N2 - Penelitian ini bertujuan untuk mengetahui hubungan antara suhu permukaan daun, leaf water potential (LWP), dan relative water content (RWC) daun tanaman kopi Robusta pada beberapa fraksi penipisan air tanah tersedia. Penelitian ini dilakukan pada 3 perlakuan, yaitu Tanaman kopi Robusta yang diairi pada kondisi kadar air tanah 20-40 centibar, 40-60 centibar, dan 60-80 centibar berdasarkan pembacaan pada alat tensiometer, kemudian ketiga perlakuan ini dilakukan 3 kali pengulangan dan pengamatan selama 5 minggu. Berdasarkan hasil penelitian yang telah dilakukan selama 24 hari, rata-rata evapotranspirasi harian tanaman kopi Robusta pada perlakuan 20-40 centibar adalah 4,1 mm/hari, 40-60 centibar adalah 4,0 mm/hari, dan 60-80 centibar adalah 3,9 mm/hari. Nilai Tc-Ta rata-rata perlakuan A, B, dan C selama 5 pengamatan adalah - 4,5 ; - 4,4 ; and - 3.8 . Nilai leaf water potential (LWP) rata-rata perlakuan A, B, dan C selama 5 pengamatan adalah - 0,4 MPa; - 0,7 MPa; and - 1,0 MPa. Nilai relative water content (RWC) daun rata-rata perlakuan A, B, dan C selama 5 pengamatan adalah 89 %; 85 %; dan 81 %. Hal ini menunjukkan bahwa, cekaman air dapat meningkatkan suhu permukaan daun, leaf water potential (LWP), dan menurunkan relative water content (RWC) daun tanaman kopi Robusta. Kata Kunci : Evapotranspirasi, Tc-Ta, leaf water potential (LWP), relative water content (RWC) daun ANALYSIS OF AVAILABLE SOIL WATER DEPLETIONS ON ROBUSTA COFFEE PLANT USING PRESSURE CHAMBER This study aims to determine the relationship between the canopy temperature, leaf water potential (LWP), and relative water content (RWC) of leaves Robusta coffee plant on some available soil water depletions. The research was conducted on 3 treatments, namely Robusta coffee plants are watered on condition of soil moisture content of 20-40 centibar, 40-60 centibar, and 60-80 centibar based on instrument readings tensiometer, then a third treatment is performed 3 repetitions and observation for 5 weeks. Based on the research for 24 days, average daily evapotranspiration Robusta coffee plants at 20-40 centibar treatment is 4,1 mm/day, 40-60 centibar is 4,0 mm/day, and 60-80 centibar is 3,9 mm/day. The value of Tc-Ta average treatment A, B, and C for 5 observation was - 4,5 ; - 4,4 ; and - 3.8 . The value of leaf water potential (LWP) average treatment A, B, and C for 5 observation was - 0,4 MPa; - 0,7 MPa; and - 1,0 MPa. The value of relative water content (RWC) of leaves average treatments A, B, and C for 5 observation were 89%; 85%; and 81%. These show that, water stress can increase the canopy temperature, leaf water potential (LWP), and lower relative water content (RWC) of leaves Robusta coffee plants. Keywords : Evapotranspiration, Tc-Ta, leaf water potential (LWP), relative water content (RWC) of leaves PB - FAKULTAS PERTANIAN TI - ANALISIS FRAKSI PENIPISAN AIR TANAH TERSEDIA PADA TANAMAN KOPI ROBUSTA DENGAN MENGGUNAKAN PRESSURE CHAMBER AV - restricted ER -