Judul: Pengaruh Arah Guludan Lahan Terhadap Kadar Air Tanah dan Biomassa Tanaman Kentang (Solanum tuberosum L.)
Abstrak: In Indonesia, potatoes (Solanum tuberosum L.) were cultivated in highland area. An effective techniques of deciding guludan direction are needed to plant potatoes in slope areas. This study examined influence of guludan direction to soil water content and biomass production. In this study, soil water content and biomass of plant (tubers) were measured on three treatments of guludan direction; diagonal (GD), parallel (GS), and cross (GM) of the contour. The techniques of deciding guludan causing the values of soil moisture content varied according to time. It occured due to the differences of evapotranspiration, interception, water absorption, runoff, and the ability of soil to hold water. High soil moisture content does not necessarily produced high biomass of tuber. Pototoes in guludan transverse direction may able to grow better than guludan with diagonal and parallel directions. The biggest biomass of tuber produced in guludan cross direction of the contour. Statistically, the impact of guludan direction treatments and blocks are not real to soil water content and biomass of tubers at α = 5%.
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Judul: Transmisi Radiasi Surya dan Koefisien Pemadaman Tajuk Tanaman Kentang (Solanum tuberosum L.) di Galudra Cipanas – Jawa Barat
Abstrak: Potatoes are one of the important vegetable crops in Indonesia. In general, potato can grow in the tropics and subtropics. In an effort to develop this plant in Indonesia is necessary to study the environmental conditions suitable for the growth and development, in relation to climate variables. One of the important climatic variables is the solar radiation. The study was conducted in the Village of Galudra, Cipanas, West Java with the aim to find the proportion of radiation transmitted by the potato crop and canopy extinction coefficient. Transmission of radiation is the radiation energy that passes on the ground under the canopy while the canopy extinction coefficient is the rate of reduction of radiation by the plant canopy. Transmission of radiation is a function of LAI, where LAI higher LAI will result in reduced transmitted radiation. The canopy extinction coefficient and radiation interception (Qint) increased with LAI. This is because the ability of canopy to cover the soil surface decreases by which so much radiation escapes into the ground under the canopy.
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Judul: Sintesis dan Pencirian Kompleks Fe(III)-Kuersetin
Abstrak: Quercetin belongs to flavonols which is able to chelate metal ions. Quercetin may chelate metal ions at 3’,4’-catechol, 3- or 5-hydroxycromone sites. In this study, quercetin was complexed with Fe(III). The complex with Fe(III) ions from FeCl3·6H2O was more stable than the complex derived from Fe(NO3)3·9H2O. The quercetin was yellow in color and showed maximum wavelengths (λ􀭫􀭟􀭶) at 250 and 370 nm. The Fe(III)-quercetin complex from Fe(NO3)3·9H2O was yellowish green with 􀟣􀭫􀭟􀭶 at 280 and 420 nm, whereas that from FeCl3·6H2O was dark green with 􀟣􀭫􀭟􀭶 at 280 and 430 nm. The 􀟣􀭫􀭟􀭶 shift indicated that the complex was formed at 3-hydroxychromone site. The Fe(III)- quercetin complex was formed with 1:1 metal-ligand mole ratio based on atomic absorption spectrophotometry analysis and the X-ray diffractogram showed that the crystallinity of the complex was 37%.
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