The effects of kencur (Kaempferia galanga L.) extract and storage period on seed borne fungi and citrus (Citrus sp.) seed viability

Abstract

Abstract. The recalcitrant seeds need a high moisture level during in storage to prevent loss its viability. The storage at a high moisture level is a favorable condition for fungi growth and on the other hand, a low seeds moisture level will loss the seeds viability. The citrus seeds as one of recalcitrant seeds need a special condition in storage. The storage of citrus seeds by using kencur (Kaempferia galangal L.) extract can protect the seeds against fungi during storage and preserve its viability. The purpose of this research was to determine the best concentration of K. galanga extract which protects 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 seed used was Keprok variety from Ponorogo. The research design was a Randomized Completely Block Design (RCBD), with the treatments: (1) included the seeds without being stored and without being given by K. galanga extract, (2) the seeds were stored for 2 weeks with 100%, 75%, and 50% K. galanga extract, (3) the seeds were stored for 4 weeks with 100%, 75%, and 50% K. galanga extract, (4) the seeds were stored for 6 weeks with 100%, 75%, and 50% K. galanga extract, and (5) the seeds were stored for 8 weeks with 100%, 75%, and 50% K. galanga extract. Data were analyzed by using F test with 5% and 1% significance levels. If there were real differences, it was continued to be tested by using a Duncan multiple range test with 5% significance level. The results of this research showed that K. galanga extract by 50% was the best concentration that protected the citrus seeds against fungi for 2 weeks of storage. The storage of citrus seeds with K. galanga extract more than 2 weeks decreased seeds viability. The dominant kinds of fungi that attack citrus seeds in the storage were Aspergillus spp. and Penicillium spp., obtained by using a blotter test.