PERBANDINGAN UJI TETRAZOLIUM DAN RADICLE EMERGENCE DALAM MENDUGA VIABILITAS BENIH KOPI ARABIKA (Coffea arabica L.) / The Comparison of Tetrazolium and Radicle Emergence Test to Estimate the Viability of Arabica Coffee (Coffea arabica L.) Seeds

Abstract
Description
Development of seed testing methods for tetrazolium (TZ) and radicle emergence (RE) needs to be conducted in order to obtain fast, precise and applicable result in the field. The objective of this study was to compare the two rapid test methods of Arabica coffee seed viability, tetrazolium and radicle emergence test. The experiment was conducted at Quality Seed Testing Laboratory, Balai Besar Perbenihan dan Proteksi Tanaman Perkebunan Surabaya from beginning of January until March 2018. Three lots of Arabica coffee (Coffea arabica var. Sigarar Utang) (Lot A = harvest in 1st week of August, 2017; Lot B = 3rd week of August, 2017; and Lot C = 1st week of September, 2017) were obtained  from Indonesian Coffee and Cocoa Research Institute, Jember. The experiments used completely randomized design with four replications. The result showed that the viability using TZ is faster than using RE test. Regression equation models for estimating seed viability are less precise, while the estimation method of paired sample t-test is sufficient to predict the actual value of the seed viability. Radicle emergence is longer than tetrazolium which is for 14 days. The regression equation model of the radicle emergence is  sufficient to predict the seed physiological quality parameter.Keywords: viability, tetrazolium, radicle emergence, coffee seed AbstrakPengembangan metodologi uji benih menggunakan tetrazolium (TZ) dan kemunculan radikula (radicle emergence) diperlukan untuk memperoleh hasil yang cepat, tepat dan aplikatif di lapangan.  Tujuan penelitian adalah membandingkan dua metode pengujian viabilitias benih kopi Arabika, yaitu uji tetrazolium dan radicle emergence (kemunculan radikula). Penelitian dilaksanakan di Laboratorium Pengujian Mutu Benih, Balai Besar Perbenihan dan Proteksi Tanaman Perkebunan Surabaya, mulai bulan Januari sampai Maret 2018. Tiga lot benih kopi Arabika varietas Sigarar Utang (Lot A : panen minggu I bulan Agustus 2017, Lot B : minggu III bulan Agustus 2017, Lot C : minggu I bulan September 2017) diperoleh dari Pusat Penelitian Kopi dan Kakao Indonesia. Rancangan yang digunakan adalah rancangan acak lengkap satu faktor (lot benih) dengan empat kali ulangan. Hasil penelitian menunjukkan bahwa pengujian viabilitas kopi dengan metode TZ lebih cepat (4 hari) dibandingkan dengan metode kemunculan radikula (14 hari). Penggunaan model regresi untuk menduga viabilitas biji kurang tepat, sementara penggunaan t-test berpasangan sangat tepat untuk menduga nilai yang sebenarnya dari viabilitas biji. Oleh karena itu, metode pendugaan mutu benih kopi Arabika berdasarkan kemunculan radikula lebih tepat untuk digunakan di lapangan.Kata kunci: viabilitas, tetrazolium, kemunculan radikula, benih kopi
Keywords
viability;tetrazolium;radicle emergence;coffee seed
Citation