Judul: Pengaruh media simpan, ruang simpan, dan lama penyimpanan terhadap viabilitas Propagul Rhizophora stylosa Griff.
Abstrak: Indonesia as an archipelagic country has a coastline and partly overgrown with mangrove forest which is the dominant type of coastal areas. However, at present the mangrove forests have been degraded which causes a decrease in forest potency. The effort that can be done to improve the return potential of these mangrove forests is by rehabilitation of mangrove forest. Rhizophora sp., including the type of Rhizophora stylosa Griff., is a pioneer tree species in the mangrove forest which has an important meaning in the mangrove forest etablishment. The main problem of this type of R. stylosa that is the seed classified into the recalcitrant ones. Therefore, the technique of seed storage is a very important activity to be developed for supporting the success of mangrove rehabilitation activities that have been degraded. The purpose of this study is to discover the influence of storage media, storage room, and time of storage on the propagule viability of R. stylosa, and to compare the R. stylosa propagule germination potential between cutting test and directly propagule germination test results. The research was conducted at the greenhouse and Silviculture Laboratory, Faculty of Forestry IPB and Seed Technology Research Institute Laboratory (BPTP), Bogor. This study used a factorial experiment with completely randomized design (CRD) factorial 5x2x2 with 3 replicates. The details of the factors are: factor A (time of storage) consists of A0 (0 weeks), A1 (1 week), A2 (2 weeks), A3 (3 weeks), and A4 (4 weeks); factor B (storage room) consists of B1 (AC room) and B2 (living room); and factor C (storage media), consists of C1 (sawdust) and C2 (coconut husk). The data collected is propagule viability, the percentage of rooted propagule, moisture content of propagule, propagule germination, germination value of propagule, the growth rates of propagule and shoot and seedling root to ratio of R. stylosa. Based on these results, it is known that the influence of interaction between treatment storage time, storage room, and storage media caused a significant difference to variable germination propagule R. stylosa. The influence of interaction between storage time and storage media caused significant differences on germination, germination value, the growth rates of propagule, and seedling root to shoot ratio of R. stylosa. The influence of interaction between storage room and storage media caused significant differences to the percent of rooted propagule R. stylosa. In this study, coconut husk media storage that is placed in the air conditioner room capable to maintaining the viability of R. stylosa propagule until the time of storage for 4 weeks. The result of estimation R. stylosa propagule viability with cutting test is relatively similar with the directly propagule germination test results.
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Judul: Pengaruh media simpan, ruang simpan dan lama penyimpanan terhadap viabilitas Propagul Rhizophora mucronata
Abstrak: The potention of mangrove forests in Indonesia has been decreasing. Therefore, rehabilitation is necessary in order to maintain sustainability of forest ecosystems. One of the efforts is the replanting of mangrove forest. The success of planting depends on the availability of seed. Seeds can not be obtained any time if needed so that storage seed is necessary for seed viability can be maintained within a certain time period until the time of planting arrives. The problem has been arise because of Rhizophora mucronata is a recalcitrant seed, which is at certain moisture content that relatively high, the propagule tend to be easy to germinate and if the moisture content is low, the propagule will be die or loss of their viability. This study aims to investigate the influence of storage media, storage room and time of storage on propagules viability of Rhizophora mucronata and to compare the germination from the rapid test (cutting test) with the germination from the direct test. This study used a factorial experiment with completely randomized design (CRD) factorial 5x2x2 with 3 replicates. The details of the factors are: factor A (time of storage) consists of A0 (0 weeks), A1 (1 week), A2 (2 weeks), A3 (3 weeks), and A4 (4 weeks); factor B (storage room) consists of B1 (AC room) and B2 (living room); and factor C (storage media) consists of C1 (sawdust) and C2 (coconut husk). Working procedures of this study consist of the preparation phase (the container store, room storage, storage media and germination media), collecting of propagule, propagule selection, storage of propagule, propagule cutting test, seeding propagule, maintenance and retrieval of data. The data collected is the result of cutting test from propagule, the percentage of rooted propagule (PB), moisture content (MC), germination (DB), germination value (NP), the growth rates (KT), shoot and root ratio (NPA). Based on these results, the influence of interaction between storage time, storage room and storage media caused significant differences on germination propagule R. mucronata. The influence of interaction between storage time and storage room caused significant differences to the percent of rooted from propagule R. mucronata. The influence of storage time and storage media caused significant differences in seedling roots to shoot ratio of R. mucronata. In this study, coconut husk media storage that is placed in the air conditioner room capable to maintaining the viability of propagule R. mucronata until the time of storage for 4 weeks. The result of estimation methods viability propagule R. mucronata with cutting test is relatively similar with the directly propagul germination test results.
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Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
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