Pertumbuhan dan Produksi Paprika pada Berbagai Intensitas Radiasi Surya di Dataran Rendah, Batam(growth And Production Of Sweet Pepper Cultivated Under Different Solar Radiation Intensity At Lowland Region Of Batam)

An experiment has been conducted in Batam Island to study the response of sweet pepper which cultivated at lowland of 20 m asl, during November 2001 to May 2002. Five varieties have been used namely, Bangkok, Gold Flame, New Zealand, Spartacus and Tropica. Plants cultivated using hydroponic system under plastic house with ultra violet protection. The radiation of 100% (control) and it reduce of 25% and 50% used as treatment in order to determine the microclimate favourable for growing pepper in lowland. The results shown that reducing radiation intensity has influenced significantly on vegetatif growth, except leaf area index. The plants were grown under 100% and 25% radiation intensity performed taller with more branches compare to the plants under 50%. Variety of Spartacus has grew tallest than others. Stem diameter of control plants performed bigger than other plants, while reducing radiation intensity has no effect significantly to leaf area index. Experiment also revealed that reducing radiation intensity has significant effect on number and weight of peppers per plant, and thickness of flesh, compare to control. In general, Gold flame has produced best quality than others varieties although it has less number of fruits compare to Tropica

Indeks Kecukupan Air Untuk Penetapan Waktu Bera Kedelai Di Jawa Tengah(water Sufficiency Indices to Determine Fallow Periods of Soybean in Central Java)

Climate anomaly has impact on yield and productivity of soybean. An alternative to minimize its impact, it is important to determine period of fallow for soybean in dry land. Period of fallow was determined by using agroclimate analysis such as water satisfaction index (WSI). WSI required daily climate data, soil and agronomy parameter to calculte ETR/ETM fluctuation . Agroecology and soybean yield data were collected from October 2003 to February 2004 in Pondok Village, Ngadirejo Sub-District, Wonogiri District and in Pojok Village, Nogosari Sub-District, Boyolali District . Fallow period was analyzed using CWB-ETo, a daily water balance software developed by IAHRI based on FAO method. WSI was calculated for El-Nino and La-Nina years to determine planting period. The result showed that fallow period were different between locations due to soil and climate variability. The longest fallow period is Blora District from Januri III to October II. While the shortest fallow period are Semarang and Magelang

Pemodelan Tanaman Jarak Pagar (Jatropha Curcas L.) Berbasis Efisiensi Penggunaan Radiasi Surya,ketersediaan Air Dan Nitrogen(crop Modeling of Jarak Pagar (Jatropha Curcas L.) Based on Radiation Use Efficiency,water and Nitrogen Available)

A number of crop growth simulation models have been developed using the radiation use efficiency (RUE) concept to predict crop growth and yield in various environments. These models generally calculate daily biomass production as the product of the quantity of radiation intercepted and RUE. Besides that biomass production was deterimined by water and nitrogen available factor. So, this research was carried out to quantify the RUE, biomass and leaf area index on Jatropha under rainfall condition, four levels of nitrogen fertilizer (N) and two and three population densities (P) planted twice. The experiments used a systematic Nelder fan design with 9 spokes and 4 – 5 rings were conducted at SEAMEO-BIOTROP field experiment in 2007. Data from the first experiment were used for parameterization and calibration and the second experiment data for model validation. Based on parameterization, we found that RUE can prediction above ground biomass accumulation of Jatropha were 0.94 (r=0.83) g MJ-1 to 1.3 (r=0.75) g MJ-1. Water availability was between ψ=-30 kpa and ψ=-1.5 MPa for field capacity and wilting point, respectively. Nitrogen demand of root, stem, leaf and grain N were (Ndemr=0.75), (Ndems=0.60), (Ndeml=2.53), and (Ndemg=2.41), respectively. Validation showed that model can simulate crop growth and development of Jatropha

Pendugaan Defisit Air Tanaman Jarak (Ricinus Communis L) Berdasarkan Model Simulasi Dinamika Air Tanah(prediction Water Deficit Of Castor Oil (Ricinus Communis L) With Dynamic Soil-water Model Simulation)

Construction dynamic model soil – water that describes relationships between crop growth and development and environmental factors (weather and soil) can be further developed to be employed as a decision support tool . The objectives of the research : (1) to know interaction of factor weather , soil, castor oil crop, (2) construction dynamic model soil – water , (3) monitoring water deficit factor at level of water irrigation. The research consisted field observation and construction model. The experimental results were used to determine quantitative relationships to obtain model parameters, calibration, and validation. This research was conducted in field experimental station of Balitpa Sukamandi, and it was arranged in split plot design with three replications. Two variety of castor oil as main plot design were : (1) ASB 81, (2) ASB 60. Three levels of water irrigation as sub plot design were : (1) No water irrigation, (2) ½ ETp, (3) 1 ETp. Field measurements included weather variables, soil, and crop. The t-test does not indicate significant difference between observed and predicted soil water content. The model is valid and reasonably well for predicting soil water content as long as castor growth . The dynamic model soil-water can be employed as a decision support tool in the management of castor oil plantations in Indonesia

Efisiensi Penggunaan Radiasi Surya dan sebagai Dasar dalam Model Jarak Pagar(radiation Use Efficiency AS Basis The Crops Modeling Of Jatropha)

Plant growth interpretation in term of accumulated intercepted solar radiation and the radiation use efficiency (RUE) was used to study the growth and analysis of Jatropha (Jatropha curcas L.). A number of crop growth simulation models have been developed using the RUE concept to predict crop growth and yield in various environments. These models generally calculate daily biomass production as the product of the quantity of radiation intercepted and RUE. This research was carried out to quantify the RUE, biomass and leaf area index on Jatropha under rainfall condition, four levels of nitrogen fertilizer (N) and three population densities (P) planted twice. The experiments used a systematic Nelder fan design with 9 spokes and 4 – 5 rings were conducted at SEAMEO-BIOTROP field experiment in 2007. Data from the first experiment were used for parameterization and calibration and the second experiment data for model validation. Values of RUE were determined by nitrogen fertilizer and plant density. Based on parameterization, we found that RUE for prediction above ground biomass accumulation of Jatropha were 0.94 (r=0.83) g MJ-1 to 1.3 (r=0.75) g MJ-1. Validation between model prediction and field experimental data showed that model can simulate crop growth and development of Jatropha

Penyusunan Metode Penentuan Indeks Kerawanan Wilayah Dan Pemetaan Wilayah Rentan Penyakit Demam Berdarah Di Indonesia

This research was aimed to develop method for determining regional vulnerability index of dengue fever disease and its zone in Indonesia particularly for regional district. The vulnerability index (IK) was developed by combining data on intensity, time series recorded data on the incidences for 3 years consecutively (m), and frequency of dengue\u27s incidences, light (Fr), medium (Fs) and heavy (Fb) incidence. Analysis on distribution of monthly IR showed that the IR\u27s values at probability of 25%, 75%, and 99% are 0.4, 2.8 and 30.1, respectively, where in monthly scale, the light incidence is within a range of 0<IR<0.4, the medium is of 0.4<IR<2.8; and the heavy is of IR>2.8. The slope coefficients of Fr, Fs, and Fb for calculating the IK was determined by averaging the IR\u27s values for the each incidence. The values of IK were mapped to develop the map of regional vulnerability index or called as Regional Vulnerability Index Zone. The map showed that the most vulnerable region covered big cities particularly those which lie on Java Island and clustered into cluster 3 and 2. Pattern and value of the monthly vulnerability index differ significantly for each cluster

Biological Properties of Rhopalosiphum Padi Linn. in Two Habitats with Different Climate Regims

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Analisis Pengaruh Faktor Cuaca terhadap Dinamika Populasi Wereng Batang Coklat (Nilaparvata Lugens Stål) yang Tertangkap Lampu Perangkap

Nilaparvata lugens Stål (brown planthopper [BPH]) is one of the major pests that cause a decline in rice productions. BPH population abundance in rice crops is affected by weather factors. An early indication of the BPH population abundance in the crop can be seen from the number of captured BPH on light traps. This study aims to analyze the influence of weather factors on the population dynamics of BPH, caught by the light traps. The method analysis used is correlation analysis and linear regression analysis. When multicollinearity problems occur among the weather factors, the influence was analyzed using principal component regression method. The result showed that rainfall, minimum humidity, and rainy days have a strong correlation to the BPH population dynamics. Based on subset tests between these three factors, two best factors were chosen, namely the rainy days and minimum humidity. The regression equation between rainy days and minimum humidity against the BPH population clearly describes the relationship of BPH population that increases along with the increase in the number of rainy days accompanied by the fluctuation of minimum humidity in the environment