Judul: eanekaragaman Fungi Mikoriza Arbuskula (FMA) di bawah Tegakan Tanaman Jabon (Anthocephalus cadamba Miq.) di Pemalang Jawa Tengah
Abstrak: Mycorrhiza is a form of symbiosis mutualism between fungi and the roots of plants. Arbuscular mycorrhizal fungi (AMF) has some functions, one of them is increasing nutrients absorption, especially P. The sample of root and soil used in this research taken from a stand of jabon plants in Pemalang, at the coastal and mountainous area. Observation colonization on plant roots carried out through staining roots and isolation of spores from soil samples is done by using the wet sieving and decanting method. Spores were identified by looking at the spores reaction after etched with a Melzer solution. The result of the research show that the biggest average of root colonization, is found at PML 2.2 is 73.33%. Where as the lowest average of root colonization is found at PML 2.5, is 46.89. In this research is found 3 type of Genus that is Glomus, Acaulospora and Scutellospora. Glomus is the most dominant and are found in all location. The highest density of spores population is at PNK 1. The growth of plants in a coastal area better than a mountainous region.
Keyword: spore density, diversity, colonization, arbuscular mycorrhizal fungi

Judul: Keanekaragaman Fungi Mikoriza Arbuskula di bawah Tegakan Tanaman Agroforestri Jabon (Anthocephalus cadamba Miq.) di Purwakarta, Jawa Barat
Abstrak: Anthocephalus cadamba is a one of tree species from Rubiaceae family that may symbiotic with arbuscular mycorrhizal fungi (AMF). The presence of AMF is very important for the soil nutrient existence, such as P, K, Mg, Fe, and also Mn to increase the growth of plants. The purpose of this research is to identify the diversity of AMF spores under stand of jabon agroforestry plants and to analyze the AMF status on various jabon planting patterns. Spores isolation was taken from soil sample using wet sieving method and decanthing method. Spores from the isolation morfologically identified by observing spores reaction through Melzer’s liquid. The result of this research indicated that soil chemical characteristic on three planting patterns of jabon do not give any concrete effects to the percentage of AMF’s root colonization. There are three genus of AMF found on the research location consist of Glomus sp., Acalauspora sp., and Scutellospora sp. Based on statistical analysis result, the jabon intercropping planting patterns which combining cucumber plants resulting the highest value of both diameter and height growth on various jabon planting patterns.
Keyword: root colonization, planting pattern, arbuscular mycorrhizal fungi

Judul: Truncated Stop Loss as a Optimal Solution of Reinsurance Agreement in One-Period Model
Abstrak: Reinsurance is one of risk management efforts of an insurance company, which is called the cedent. Similar with insurance, reinsurance constitutes the cedent to pay the premium. We consider one-period reinsurance model and derive a rule which minimizes the ruin probability of the cedent for a fixed reinsurance premium. Therefore, it is needed to construct an optimal reinsurance agreement for the cedent. The premium is calculated according to four different principles, i.e. economic, generalized zero-utility, Esscher, and mean-variance principles. Stop loss is a reinsurance contract which protect the insurance company for losses that exceed a certain amount. The result of this research shows that a truncated stop loss is an optimal agreement in the class of all reinsurance contracts with various premiums calculated using above mentioned principles.
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