Judul: Pengaruh sistem olah tanah dan pemupukan terhadap pertumbuhan dan produksi beberapa genotipe kedelai di lahan kering masam
Abstrak: Indonesia has quite extensive dry land for the development of the soybean plants. Low of pH and water availability in the dry season are the main factors that become obstacles on planting soybean in dry land. It can be overcome with tolerant genotypes of dry land and cultivation techniques of tillage. The objective of the research was to determine the response of soybean genotypes under cultivation techniques of tillage on acid dry land. The research was conducted at Krawangsari, Natar, South Lampung District, and Lampung Province, Indonesia from June to November 2011. The experiment was performed using a split plot design with three replications. The main-plot of the experiment was soybean genotype consisted of SP-30-4, PG-57-1, Tanggamus and Anjasmoro. The subplot was combination of tillage systems (furrow and convensional) and input types (fertilizers, lime, compost and organic mulch). The results showed that the dry weight, number of fill pods and seed weight per plot were not significantly different among genotypes. Furrow tillage system combined with fertilizers, lime, compost and organic mulch can increase plant nutrient uptake, dry weight, number of fill pods and seed weight per plot.
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Judul: Pengaruh pemupukan fosfor dan kalsium terhadap serapan hara dan produktivitas dua genotipe kedelai pada budidaya kering dan jenuh air
Abstrak: The objectives of this research were to study the effect rates of P and Ca fertilizers on productivity and nutrient uptake of two soybean genotypes in dry culture and saturated soil culture, and to compare the nutrient uptake and productivity in soybean dry culture with saturated soil culture. The experimental design was split split plot with three factors i.e. phosphorus, calcium and genotype planted in dry culture and saturated soil culture. Dry culture with phosphorus fertilizer application (72 kg P2O5/ha) increases the number of filled pods and grain weight per plot. Number of pods of Tanggamus variety was greater than Anjasmoro variety. Liming had no effect on productivity. Path analysis showed that largest direct effect to grain weight were plant height and leaf weight. Increased rate of P and Ca fertilizer increased the uptake of P and Ca, but variety Tanggamus is more responsive than variety Anjasmoro. Saturated soil culture with phosphorus fertilizer (72 kg P2O5/ha) and lime (1 ton/ha) increased the number of pods content and grain weight per plot. Variety Tanggamus had higher number of pods and grain weight per plot than variety Anjasmoro. Interaction of phosphorus fertilizer 72 kg P2O5/ha with lime 1 ton/ha increased grain weight per plot. Largest direct effect on increasing grain weight is plant height and the number of branches. Phosphorus application (72 kg P2O5/ha) and liming (1 ton/ha) also give highest uptake of P and Ca. Saturated soil culture technology can be applied to increase soybean nutrient uptake and productivity than dry culture.
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Judul: Cycle Hamilton pada Graf Lengkap, Graf Regular, dan Graf 2-Connected 4-Regular Berorder Kurang dari Sepuluh
Abstrak: Suatu graf disebut graf Hamilton apabila graf tersebut memuat cycle Hamilton, yaitu cycle yang melewati setiap vertex tepat satu kali. Menentukan keberadaan cycle Hamilton pada suatu graf dapat menggunakan syarat cukup yang berupa teorema-teorema yang telah diperkenalkan sejak tahun 1950-an. Beberapa syarat cukup yang dibahas dalam karya ilmiah ini adalah syarat cukup yang berhubungan dengan graf lengkap dan graf regular. Suatu graf lengkap berorder 𝑛������ ≥ 3 dan graf r-regular berorder 𝑛������ ≤ 2𝑟������ + 1 merupakan graf Hamilton, Karena kedua graf tersebut memuat cycle Hamilton. Selanjutnya, syarat cukup tersebut digunakan untuk menentukan keberadaan cycle Hamilton pada graf 2-connected 4- regular berorder kurang dari 10.
Keyword: graf Hamilton, graf regular, graf lengkap, graf 2-connected 4-regular