Pengaruh ekstrak kencur dan lama simpan terhadap cendawan terbawa benih dan viabilitas benih jeruk ( Citrus sp.)

Oleh :
Dewi Devy Dayuni - H1103005 - Fak. Pertanian

Benih rekalsitran mempertahankan kadar air tetap tinggi untuk menjaga viabilitasnya, sehingga menjadi kendala jika benih tersebut disimpan. Penyimpanan dengan kadar air benih yang tinggi dapat menyebabkan pertumbuhan cendawan yang merugikan, namun penurunan kadar air benih pun tidak dapat dilakukan karena mengakibatkan benih kehilangan viabilitasnya. Benih jeruk sebagai salah satu benih rekalsitran perlu penyimpanan khusus dengan menggunakan ekstrak kencur guna melindungi benih jeruk dari serangan cendawan sekaligus untuk mempertahankan viabilitasnya. Tujuan penelitian ini adalah untuk mengetahui konsentrasi ekstrak kencur terbaik yang dapat melindung benih jeruk selama penyimpanan serta pengaruhnya terhadap jenis cendawan, persentase infeksi cendawan dan viabilitas benihnya. Penelitian ini dilaksanakan pada bulan September sampai November 2004 di laboratorium hama dan penyakit tanaman dan rumah kaca Fakultas Pertanian Unversitas Sebelas Maret. Benih jeruk yang digunakan berasal dari kebun Ponorogo dengan varietas keprok. Rancangan percobaan yang digunakan adalah Rancangan Acak Kelompok Lengkap (RAKL) dengan 13 perlakuan : benih tanpa disimpan dan tanpa diberi perlakuan ekstrak kencur, benih disimpan selama 2 minggu dengan konsentrasi ekstrak kencur 100%, 75%, dan 50%, benih disimpan selama 4 minggu dengan konsentrasi ekstrak kencur 100%, 75% dan 50%, benih disimpan selama 6 minggu dengan konsentrasi ekstrak kencur 100%, 75% dan 50%, dan benih disimpan selama 8 minggu dengan konsentrasi ekstrak kencur 100%, 75% dan 50%. Data hasil pengamatan dianalisis dengan uji F taraf 5% dan 1%. Apabila terdapat beda nyata maka dilanjutkan dengan uji jarak berganda Duncan taraf 5%. Hasil penelitian menujukkan bahwa konsentrasi ekstrak kencur 50 persen memberikan hasil terbaik yang dapat melindungi benih jeruk dari cendawan selama 2 minggu penyimpanan benih. Penyimpanan benih jeruk lebih dari 2 minggu dengan pemberian ekstrak kencur mengakibatkan penurunan viabilitas benih. Jenis cendawan simpan yang dominan menyerang benih jeruk pada uji blotter test adalah Aspergillus spp. dan Penicillium spp. The recalcitrant seeds need a high moisture level during storage to prevent loss its viability. The storage at high moisture level is a favorable condition for fungi growth and the other hand low of seeds moisture level will loss the seeds viability. The citrus seeds as one of recalcitrant seeds need special storage using the Kaemferia galanga extract in order to protect the seeds against fungi during storage and preserve its viability. The purpose of this research was to study : the best concentration of Kaemferia galanga extract which protect the citrus seeds against fungi as long as period storage, the kind of fungi and its percentage of infection, and the citrus seeds viability. This research was carried out in September until November in 2004 at Plant Pest and Disease laboratory and Greenhouse of Agricultural Faculty of Sebelas Maret University. The citrus seeds used was Keprok variety from Ponorogo. The research design was RCBD (Randomized Completely Block Design), with treatments : the seeds without being stored and without being given Kaemferia galanga extract, the seeds were stored for 2 weeks long with 100%, 75% and 50% Kaemferia galanga extract, the seeds were stored for 4 weeks long with 100%, 75% and 50% Kaemferia galanga extract, the seeds were stored for 6 weeks long with 100%, 75% and 50% Kaemferia galanga extract, and the seeds were stored for 8 weeks long with 100%, 75% and 50% Kaemferia galanga extract. Data observation was analyzed by using F test with 5% and 1% level. If there was real differences then it continued by using Duncan multiple range test 5% level. The results of this research showed that the Kaemferia galanga extract 50% was the best concentration that protect the citrus seeds against fungi for 2 weeks long of storage. The storage of citrus seeds with Kaemferia galanga extract more 2 weeks decreased seeds viability. The dominant kinds of fungi that attack citrus seeds in the storage were Aspergillus spp. and Penicillium spp, the method using blotter test.