Judul: Uji Antagonis Trichoderma harzianum terhadap Botryodiplodia sp. Penyebab Penyakit Mati Pucuk pada Jabon (Anthocephalus cadamba) secara in Vitro
Abstrak: Frenquently issues emerge on jabon (A. cadamba) plantations development is Botryodiplodia sp. aggression that cause dieback desease. Biology control is necessary as effort to hamper pathogen growth with lowest environmental contamination risk compared to non biological control. One of biological control configuration is using biological control agent T. harzianum the research supposed to acquire T. harzianum potency as biological control agent against Botryodiplodia sp.. In this research antagonist examination using direct method (dual culture) and indirect method (filtrate T. harzianum). Experiment model is using completely randomize design and in time completely randomize design. This research result shows that T. harzianum disposal in antagonist examination on direct mothode and indirect method against Botryodiplodia sp. growth. This case shows that T. harzianum has potency to against Botryodiplodia sp. growth. So that could be used as biological desease control on jabon (A. cadamba) especially caused by Botryodiplodia sp..
Keyword: Bogor Agricultural University (IPB), antagonistic examination, Trichoderma harzianum, Botryodiplodia sp

Judul: Keefektifan Kitosan dalam Mengendalikan Botryodiplodia sp. pada Jabon (Anthocephalus cadamba) secara in Vitro
Abstrak: The problem that frequently occurred in jabon forest plantation is the attack of Botryodiplodia sp. leading to dieback. Biological control is a fascinating subject to study especially the usage of chitosan. this research aims to measure chitosan’s effectiveness as an alternative disease control for jabon (A. cadamba) caused by Botryodiplodia sp. in vitro way. The experiment model used are completely randomize design and in time completely randomize design. Treatment consist of adding chitosan liquid to three medias, which is poteto dextrose agar (PDA), czapex, and poteto dextrose broth (PDB) with chitosan’s concentration level of 0.0 %, 0.5 %, 1.0 %, and 1.5 %. the Result of the experiment indicated that chitosan addition have significant effect to prevent the growth of Botryodiplodia sp. The best relative prevention score at PDA is 79 %, gained by addition of liquid chitosan 1.0 %, while on czapex and PDB the best score are 73 % and 58 % respectively with addition of 1.5 % liquid chitosan.
Keyword: relative prevention, chitosan, Botryodiplodia sp., Anthocephalus cadamba

Judul: Cycle Hamilton pada Graf Lengkap, Graf Regular, dan Graf 2-Connected 4-Regular Berorder Kurang dari Sepuluh
Abstrak: Suatu graf disebut graf Hamilton apabila graf tersebut memuat cycle Hamilton, yaitu cycle yang melewati setiap vertex tepat satu kali. Menentukan keberadaan cycle Hamilton pada suatu graf dapat menggunakan syarat cukup yang berupa teorema-teorema yang telah diperkenalkan sejak tahun 1950-an. Beberapa syarat cukup yang dibahas dalam karya ilmiah ini adalah syarat cukup yang berhubungan dengan graf lengkap dan graf regular. Suatu graf lengkap berorder 𝑛������ ≥ 3 dan graf r-regular berorder 𝑛������ ≤ 2𝑟������ + 1 merupakan graf Hamilton, Karena kedua graf tersebut memuat cycle Hamilton. Selanjutnya, syarat cukup tersebut digunakan untuk menentukan keberadaan cycle Hamilton pada graf 2-connected 4- regular berorder kurang dari 10.
Keyword: graf Hamilton, graf regular, graf lengkap, graf 2-connected 4-regular