Uji Batang Bawah Karet (Hevea Brassiliensis, Muell-arg.) Berasal Dari Benih Yang Telah Mendapat Perlakuan Peg (Seed Coating) Dengan Beberapa Klon Entres Terhadap Keberhasilan Okulasi

For increasing rubber production, seed factor very important as rootstock origin. Seed haverecalsitran characteristic that cause the deteoration. The seed that have gotten the PEG treatment tomaintain the viability, tested further as rootstock origin. The purpose of this study was to test therootstock of the rubber (Hevea brassiliensis, Muell-Arg.) originated by the seeds that have gottenthe PEG treatment with some clones of Scion for the success of grafting the research have done onMarch until June, 2013 in the publics land at Pasar I Tanjung Sari, Medan. The design of researchthat be used is Randomize Complete Factorial Design with two factors and three replications. Thefirst factor is rootstock seed of rubber that has been gotten the seed treatment (0%, 15%, 30%, 45%PEG concentrate) and the second factor is scion (IRR 104, IRR39, IRR 72 clones). The parameterthat be observed is break bud in field, the length of bud and the diameter of bud. The result showedthat the rubber rootstock seed that have given the seed treatment did not effected significantly on allof parameters. The type of scion did not effected significantly on all of parameters. The interactionsbetween rootstock and the scion did not effected significantly also. On all of the parameters the bestresult that gained on the rootstock of rubber seed that have given by the seed treatment is theconcentrate of PEG 30% and bud of IRR 104

Uji Daya Simpan Dan Viabilitas Benih Karet (Hevea Brasiliensis Muell-arg.) Tanpa Cangkang Terhadap Konsentrasi Larutan Osmotik Dan Lama Pengeringan

The seed of rubber is a kind of recalcitrant seeds which is have a low shelf life with the result thatquickly in deterioration so it needed a special treatment in storage period to maintain the seedviability. By using the osmotic solution concentration of Polyethylene Glycol 6000 and seed dryingwhich is very helpful in recalcitrant seed storage due to it has osmotic cell potential to restrict thealteration of water and oxygen capacity in seed. This research aimed to get the optimal of osmoticsolution concentrations and drying time to maintain the seed viability of Rubber. It conducted sinceApril until June 2013 in Laboratory of Plant Breeding, Agriculture Faculty, University of SumateraUtara. The research uses the completely randomized design with two treatments as factor and threereplications. The first factor is osmotic solution concentration of PEG 6000 of PEG 6000 : 0, 15,30, and 45 (% w/v) and other factor is drying period : 0, 4, 8, 12, 16 (hours). The results showed theosmotic solution concentration of PEG 6000 30% w/v significantly in seed growth rateafter storageperiod 3,49% etmal and maximum potential growth 64,22%. 4 hours drying period is the best inseed growth rateup to 3,49 3,89% etmalwith 66,94% maximum potential growth. The osmoticsolution concentrations of PEG 6000 30% w/v and 4-hour drying period is the best combination oftreatments which can seed growth rate up to 3,95% etmal with 66,67% maximum potential growth