Abstract. Appearance of a plant is determined by genetic factors, environmental factors and interactions between them. The genetic x environment interactions become an important concern for breeders, in addition to genetic factors. Purpose of this study was to examine the genetic x environment interactions for resistance of pepper to anthracnose. Materials used were 16 hybrids that were planted at three locations. Complete randomized block design (RCBD) was used with three replications. Replicates nested within location. Twenty of hot pepper that has been worn but is still green from each replication was inoculated with C. acutatum, PYK 04 isolate. Disease incidence was observed five days after inoculation. The results showed that the genotype x location interaction was significant different to resistance resistance caused by Colletotrichum acutatum PYK 04 isolate. Pepper genotypes stable in anthracnose resistant character in three selection environments was IPB CH3, IPB CH6, and IPB CH25. The genotypes were suitable for selection environment Ciherang, Leuwikopo and Tajur. Genotype IPB CH50 and IPB CH51 were suitable for selection environment Tajur. Imperial genotypes was suitable for the environment selection Ciherang. IPB CH5 and IPB CH4 CH5 were suitable for Lewikopo environment.

Keywords:genetic x environmental interaction, anthracnose, resistance, pepper, Colletotrichum acutatum

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Abstract. A study was conducted to determine the variation and relationships among  papaya genotypes based on morphological  and fruit characteristics  in order to produce  high quality papaya fruits. Fruit characterization study is very useful for  genotype improvement and genotype classifi cation of papaya. In this study the morphological characters of 36 genotypes were  analyzed to determine their phenotypic variabilities.  The relationships between genotypes based on all of the morphological  and fruit characteristics were tested by subjecting the data to multivariate principal component analysis and to cluster analysis. Based on the dendrogram generated from vegetative and generative characters, the 36 genotypes could be grouped into 11 clusters on a threshold of 1.6 and formed 6 clusters on a threshold of 1.8.  The dendrogram was able to explain the  close relationship between IPB 5 x IPB 1 and IPB 5 x IPB 4, IPB 2 and IPB 7, IPB 1 and IPB 3 genotype. The scattered  diagram of generative variable divided the papaya genotypes into three groups based on fruit sizes i.e small group (IPB 1, IPB 3, IPB 4, IPB 3 x IPB 4, IPB 1 x IPB 9), medium group (IPB 5, IPB 7, IPB 8, IPB 9) and big group (IPB 2, IPB 10). The IPB 1, IPB 3 and IPB 4 were different from IPB 2 in fruit shapes, petal length of male fl owers, infl orescence size and  fruit length. The hybrid plants obtained from crossings with IPB 10 were different from the other genotypes in the colours of female-, hermaphrodite-, and male fl ower-lobes. Subsequently the scatter diagrams also revealed that several genotypes i.e. IPB 2 x IPB 6, IPB 1 x IPB 5,  IPB 1 x IPB 9, IPB 5 x IPB 1 and IPB 5 x IPB 2 had superior characters  ideotype similar to IPB 1, IPB 3 and IPB 8 genotypes.

Keywords: Carica papaya, hermaphrodite, female, dendrogram, scatter diagram, ideotype

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Abstract. Xanthone in mangosteen fruit hull has antioxidant activities. The objective of this experiment was to determine xanthones content, physical and chemical characters, and antioxidant potentials of several groups of mangosteens qualities. The experiment was carried out from January 2008 to August 2008. The research used a randomized complete block design with four replications. The treatments were four physical fruit conditions: large size mangosteens (# 100 g), small size mangosteens (min. 50 g), yellow sap dotted fruits, and scabbed fruit. The parameters being observed were physical and chemical characteristics, xanthone content, and radical scavenging activity of mangosteen fruit hull extract. The results demonstrated that the physical condition of fruit signifi cantly affected physical fruit hull characters and chemical fruit characters. Characters of fruit hull, thickness, fresh weight, and dry weight, differed among fruit qualities. The physical condition of fruit hull also signifi cantly infl uenced total soluble solid and vitamin C content, but did not affect total titrable acid and degree of acidity of the fruits. Fruit hulls of all groups of mangosteen qualities had similar antioxidant properties with the IC50 value of 5.57-6.11 ppm.

Keywords: benzophenone, scab, vitamin C, yellow sap

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Abstract. Eggplant, yard long bean, and kangkong, were grown with polyethylene mulch with a drip irrigation system on Podzolic soil with low pH (4.5), low C-Organic (0.97%), very low total-N (0.17 %), low K content (0.15 me (100 g)-1), but had a high soil P2O5 concentration (13.7 ppm) to evaluate the best crop management practices under this soil condition. Combination of polyethylene mulch treatments (with and without), fertilizer (with and without), number of irrigation lines (0, 1, and 2 lines), and methods of fertilizer applications (preplant, split, and drip) were arranged in a Randomized Completely Block Design with four replications. The results showed that the use of mulch and fertilizer signifi cantly increased yield of all crops. One line irrigation system also resulted in the best yield. Preplanting application of 100% P, 50% N and K in addition to 50% N and K applied 10 times weekly was the best methods to produce Eggplant, Yard Long Bean, Kangkong under polyethylene mulched and drip irrigation system.

Keywords: Solanum melongena L, fertilization, fertigation, Ipomoea reptans L, micro-irrigation, polyethylene-mulched, Vigna unguilata L.

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