Karakteristik Penyakit Daun pada Pembibitan Empat Klon Hasil Persilangan Eucalyptus grandis x Eucalyptus urrophylla di PT Toba Pulp Lestari Tbk Kabupaten Toba Samosir, Sumatera Utara

Abstract

Fitriani : Characterization of Disease on Seedling Leaves Four clones of Eucalyptus grandis x A cross results Eucalyptus urrophylla . PT . Toba Pulp LestariTbk . Toba Samosir , North Sumatera supervised by Nelly Anna and Edi Batara Mulya Siregar. Eucalyptus is one kind of tree that is cultivated by PT . Toba Pulp Lestari Tbk . Eucalyptus hybrid tree type is a type that is widely cultivated in the past. unfortunately this plant nurseries susceptible to pests and diseases . The purpose of this study was to characterize the symptoms of disease , measuring the level of intensity of attack and identify the cause of each disease symptoms found in Eucalyptus grandis seedlings from crosses x ecalyptus urrophylla PT . Toba Pulp Lestari . The results showed that the type of pathogen penyenyebab leaf diseases on the crop seed is Cladosporium sp , sp Cryptosporiopsis , Phaeophleospora sp and Rhizopus sp . The highest attack attack symptoms such as red spots on the leaves with the intensity of the attack reached 14.98 % , blackish spot 9.92 % , 1.72 % reddish purple spots , brown spots under the surface of the leaf 1:03 % , brown pigmentation on the surface and reddish spots 0.87 % reached 3.6 % .