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: Pendugaan kehilangan air melalui perhitungan neraca air serta analisis pertumbuhan tanaman kentang (Solanum tuberosum L.)
Abstrak: The growth and the production of a plant are determined by favourable environment. Soil is water reservoir and planting area for which the capability to keep the water in the soil will determine the total water that can be used for the plant. Water availability in the soil is used by the plant to fullfil plant’s water requirement such actual evapotranspiration and runoff which can be calculated by using the water balance. The objective of this research is to calculate the potato water loss during the measurement through the water balance and to analyse the effect on potato growth. The result of this research shows that the potato water loss (actual evapotranspiration and runoff) during measurement on 37 days until 73 days after planting is 148-191 mm or 4.6 mm/days, whereas the run off is 28-59 mm or 19-30 % from total water loss potato. The relations between soil water content and the growth rate in each treatment has a different disposed. When the storage of soil water content is high, the growth rate is uncertainly high, and vice versa. The growth rate is of the potato in this research not only influenced by soil water content, but also influenced by other factors that are not observed in this research.
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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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