Pengaruh Pemupukan N dan P Terhadap Keragaan dan Hasil Tebu Transgenik IPB 1 di PG Djatiroto, Jawa Timur

Abstract

One approach to improve sugar production and saving of fertilizer is develoving genetically modified sugarcane plants. The transgenic sugarcane IPB 1 contains bacterial phytase gene that can alter phytic acid which is a form of organic-P to become inorganic-P, so it can be used by plants. Phytase will also increase the availability of other mineral nutrients in plant tissues such as Mg2+, Ca2+, and Fe2+. The nutrients are utilized by plant for synthesis of chlorophyll and inturn will increase photosynthesis and the yield of sugarcane. The research was aimed study to (1) the effectivity of N and P fertilization on transgenic sugarcane IPB 1 by observing growth and production of sugarcane, and (2) to select seven best clones by scoring the growth and production of sugarcane. The research was conducted at PG Djatiroto Experiment Station, Lumajang, East Java. Total of 23 clones of transgenic sugarcane IPB 1 and 1 clone of isogenic sugarcane PS 851 were treated with four fertilization, i.e.: (a) 50% N and 50% P, (b) 100% N and 50% P, (c) 50% N and 100% P, and (d) 100% N and 100% P, where 100% N and 100% P, respectively, equals to 800 kg ZA/ha and 200 kg SP-36/ha. 800 kg ZA/ha and 200 kg SP-36/ha together with 100 kg KCl/ha are the recommended fertilization rate for the area. Growth parameters abserved were number of stalk, stalk height, and stalk diameter. Measurement of the growth parameters were conducted twice, i.e. at the ages of 6 and 9 months (Januari and April 2011). Production parameters, namely yield, sugar content, and sugar production were determined after sugarcane harvesting at the age of 12 months. Some data were analyzed using Statistical Analysis Software (SAS) at α value of 0,05. The results showed that the transgenic sugarcane IPB 1 can effectively utilized fertilizers as indicated by insignificant effect of fertilization treatment. The best growth and production were resulted by 50% N and 50% P fertilization. Seven best clones at this rate of fertilizaation are transgenic sugarcane IPB 1-1, IPB 1-3, IPB 1-6, IPB 1-7, IPB 1-46, IPB 1-52, and IPB 1-56 the seven best sugarcane clones.