Judul: Kemampuan Resapan Air Tanah pada Berbagai Penggunaan Lahan di Latosol Darmaga dan Andosol Cisarua
Abstrak: Forest is a natural ecosystem that has good soil properties. Land use change from forest to agricultural land led to degradate soil quality. The degradation of soil quality would be different for different soil type. The study aimed to compare infiltration capacity, the amount of organic litter, macrofauna and soil organic matter content in perennial mixed farm, annual dryland and forest on Latosol and Andosol. The results showed that the amount of organic litter, organic matter content, macrofauna and infiltration capacity of agricultural land are smaller than those of forest. Those characteristics are poorest on annual dryland. The largest difference occurs in annual dryland at Andosol for the amount of litter, soil organic matter content, macrofauna and infiltration capacity. This indicate that land use change may cause greater soil quality degradation in Andosol than Latosol.
Keyword: soil organic matter, soil macrofauna, litter, infiltration capacity

Judul: Karakteristik Fisik Tanah pada Beberapa Penggunaan Lahan di Tanah Latosol Darmaga dan Podsolik Jasinga
Abstrak: Increasing need of agriculture land each year result in the increasing of forest land conversion. Conversion of forest land to agriculture land may lead to decrease in the physical quality of the land. A research aimed to compare the difference of soil physical properties under secondary forest, mixed farms, and annual crop was conductied on two soil types i.e. Latosol Darmaga and Podsolik Jasinga. Methods used in this research were suited to the analyzed parameters. The result shows that soil under mixed farm and annual crop tend to have higher bulk density, lower total porosity, lower water availability, lower permeability, lower water field content, and higher penetrability than soil under secondary forest both in latosol Darmaga or podsolik Jasinga. The result also shows that the difference physical quality between soil under forest and soil under mixed farm and annual crop in podsolik Jasinga is higher than those in latosol Darmaga. Latosol contain higher polyvalent cations than podsolik so that it has better aggregate consilidation and more stable soil structure. This suggests that Podsolik Jasinga is more susceptible than latosol.
Keyword: Podsolik, soil physical properties, Latosol

Judul: Pengujian Virus Newcastle Disease Gen VII Isolat Lapang Sebagai Virus Standar Pada Uji Tantang Vaksin
Abstrak: This study was conducted to determine the standard of Newcastle disease virus Gene VII field isolate as a virus challenge to vaccine test. A virus suspension that has previously been tested by HA test then titrated with EID50 using 30 Specific Pathogen Free (SPF) of 10 day old chicken embryonated eggs. In addition, chicken lethal dose50 (CLD50) test were used to determine the virus titer that could cause 50% death of the chicken population. The CLD50 test was used 25 day-old-chickens (DOC) divided into 5 groups. The virus was diluted from 10-1 to 10-8. The 104 to 10-8 dilution of NDV was infected to every group of chicken via eyedrop and intranasal with 0.1 ml/chicken dosage. Haemagglutination test showed that the allantoic fluid were contain high titers of NDV is 512 HAU. The infective NDV that had been titrated by EID50 test showed the virus titers is 109 EID50/0.1 ml or 1010 EID50/ml and the virus titers of CLD50 test e.i 106.48 CLD50/0.1 ml or 107.48 CLD50/ml. These results can be concluded that the NDV Gene VII field isolates were most appropriate to be used as a standard virus to vaccine test
Keyword: Newcastle Disease Virus Gene VII, HA tes, EID50 test, CLD50 test