Buletin Kebun Raya

57-70

Authors: Lia Hapsari, Ahmad Masrum

Banana Bunchy Top Disease (BBTD) caused by Banana Bunchy Top Virus (BBTV) is one of the most serious banana diseases, constraint and devastate to the local and regional banana production. Some of banana cultivars were more readily infected by the virus, but considering no cultivars is resistant. The incidences of BBTD and the type and severity symptoms in natural conditions without any artificial inoculation were recorded. The observations results on 2009 showed that 12.14% of the total accessions indicated positively infected BBTD. The BBTD incidences were increased rapidly about twofolds per year, 28.57% in October 2011 and 54.29% in October 2011. The spread and development of BBTD is optimum at humid, high rainfall intensity and temperatures, high soil fertility and also low light intensity or shaded. The latest monitoring on February 2012 (62.14%) comprises of 64 accessions were positively infected and 39 accessions were symptomless. Those symptomless accessions were initially indicated as tolerant banana cultivars to BBTD e.g. Pisang Kepok (BBB), Pisang Sobo (BBB), Pisang Bandung (ABB), Pisang Nangka (AAB), Pisang Candi (AAB) and Pisang Raja Marto (AAB). These preliminary results are in agreement with several previous studies indicated that genotypes with one or two B genomes tend to be more tolerant to BBTD. However several cultivars which known tend to BBTD tolerant are indicated susceptible to Blood Disease. Some cultivars also showing complication symptoms both BBTD and Blood Disease.

81-92

Authors: Andes Hamuraby Rozak

The Family of Magnoliaceae is one of the most primitive taxa in the world. Knowledge of this family is essential for studies on the origin, evolution and systematics of Angiosperms. There are 223 species belongs to this family in the world and 25 of them are found in Indonesia. This paper explains taxonomy, distribution, and conservation status of the family Magnoliaceae in Indonesia.

103-115

Authors: Kartika Ning Tyas, Slamet Susanto, Iswari S Dewi, Nurul Khumaida

Indonesia has high variety of pummelo [Citrus maxima (Burm.) Merr.], but only several cultivar are cultivated extensively. Others became vurnerable and the germplasm has to be conserved to prevent their extinction. One of the conservation method is in vitro conservation using a slow growth technique. Factorial experiment was used in designing the experiment, the first factor was MS medium concentration, i.e. 1/2MS and MS. The second factor was sucrose concentration, i.e. 0; 1; 2; and 3%. The results showed that low concentration of MS medium and sucrose reducing the leaf number and shoot length but increasing the root number and length. Based on inhibition of growth, the most reducing growth was planlet on MS without sucrose.

1-9

Authors: Revis Asra, Syamsuardi Syamsuardi, Mansyurdin Mansyurdin, Joko Ridho Witono

Jernang (Daemonorops draco (Willd.) Blume) is a dioecious rattan species that produces resin on female individuals. The sex of jernang can only be identified from its inflorescences morphology. Sex survey was conducted in 5 populations of jernang, 3 populations of which in the Bukit Tigapuluh National Park (BTNP), 1 population in the secondary forest in Jambi province and 1 population in the area of rubber plantation in Jambi province. Chi-Squared test on the sex ratio of jernang showed that the ratio of the male to female in their natural habitat (Bengayoan and Tebo, 2 parts of the BTNP ecosystem and the Sepintun secondary forest) was distorted from the normal ratio of 1:1, while the cultivated jernang in Nunusan population (BTNPT) and Mandiangin were not significantly different from the normal sex ratio of 1:1. Female individuals from the cultivated population in the Mandiangin (planted in 1997) has an average number of stems per clump more on individual males (27.12) than females (26.92). The result of this study indicated that the D. draco has a good reproductive strategy and thus suitable for cultivation.

20-29

Authors: Sofi Mursidawati

Most members of family Rafflesiaceae are rare plants which found only in a restricted area in Southeast Asia. As a holoparasitic plant Rafflesia totally depends on the specific host plant in specific habitat. The rarity of Rafflesia caused the limited number of research of many biological aspects of this species. In this study, observations on the fruit and seed of R. patma and R. arnoldii were carried out in its habitat and laboratory. Figures and dimension of the seeds was recorded by Scanning Electron Microscope (SEM).

36-45

Authors: Decky Indrawan Junaedi

Cestrum aurantiacum Lindl. is an exotic species found in native remnant forest of GPNP which is located inside the Cibodas Botanic Garden (CBG). Risk assessment is an important tool to choose best decision for invasive plant management. Risk assessment analysis on C. aurantiacum in Cibodas Botanic Garden was conducted using Multi Criteria Decision Analysis (MCDA) method. Analytical Hierarchy Process (AHP) used in the valuation process. Three sub-criteria used: minimizing the ecological impact, minimizing the management cost, and maximizing the public acceptance. Five management alternatives were used: do nothing (DN), eradication (E), containment (C), bio-control (BC) and harvesting (H). Harvesting (H) recommended as the best management decision for C. aurantiacumin at CBG remnant forest. This harvesting decision is not only creating environment/ ecosystem remediation but also as sources of fund in the management activity of the area.