Judul: Selection of Potential Genotypes and Traits Evaluation of Honeydew (Cucumis melo L.).
Abstrak: Quality improvements of honeydew (Cucumis melo L.) can be carried out by developing superior hybrid varieties. This study aimed to identify potential genotypes with good fruit quality for breeding improved hybrid varieties. Two experiments were conducted from March to September 2019 at the Tajur II experimental station of the Center for Tropical Horticulture Studies (PKHT), IPB University, Bogor. The first experiment was the evaluation of S2 genotypes, and the second was the evaluation of the test crosses. Both experiments were arranged in a single-factor randomized complete block design with three replications. The first experiment evaluated ten genotypes, i.e., six S2 genotypes (IPB HD 1, IPB HD 2, IPB HD 3, IPB HD 4, IPB HD 5, IPB HD 6), three inbred lines as testers (SMM, SMF, and OMM), and one check variety (Alisha F1). Fourteen hybrids from S2 x testers were produced and subsequently tested in the second experiment with one check variety (Alisha F1). The results from both experiments indicated that the genotype had significant effects on fruit traits, except skin thickness in the S2 experiment and total soluble solids in the testcross experiment. IPB HD 1 and IPB HD 4 had good fruit traits and produced good hybrids as well. These genotypes are therefore predicted to have good potential for developing improved hybrid honeydew varieties.
Keyword: genetic diversity, fruit quality, melon breeding

Judul: Evaluation of Melon Genotypes (Cucumis melo L.) and Their Hybrids for Breeding Improved Varieties
Abstrak: Peningkatan kualitas melon dapat dilakukan dengan mengembangkan varietas hibrida unggul yang dilandasi oleh fenomena heterosis. Penelitian ini bertujuan mengidentifikasi genotipe potensial melon (Cucumis melo L.) dengan kualitas buah yang baik dan mengevaluasi karakter hibridanya. Penelitian dilakukan di rumah kaca Kebun Percobaan Cikabayan, Institut Pertanian Bogor, Bogor pada bulan November 2020–Maret 2021 dan di lahan terbuka Desa Tanjungsari, Kec. Jogorogo, Kab. Ngawi, Jawa Timur pada bulan April–Juli 2021. Bahan genetik pada percobaan I ialah IPB G30, IPB G1, IPB M23, IPB M21, dan varietas Alisha F1. Bahan genetik percobaan II yaitu 13 genotipe hibrida: H1, H2, H3, H4, H6, H7, H8, H9, H10, H11, H12, H13, H14; 4 genotipe tetua: IPB G1, IPB G30, IPB M21, IPB M23; dan varietas pembanding: Alisha F1. Percobaan I disusun dengan rancangan kelompok lengkap teracak (RKLT) faktor tunggal, sedangkan percobaan kedua disusun dengan rancangan kisi alfa faktor tunggal. Hibrida H4 unggul pada karakter bobot buah, bobot buah per plot, dan padatan terlarut total, sedangkan H9 unggul pada karakter warna dan rasa daging buah, serta ukuran buah. Heterosis dan heterobeltiosis tertinggi dimiliki oleh hibrida H7, H10, dan H14. Galur IPB M23 dan IPB G30 berpotensi sebagai tetua untuk perakitan varietas unggul., Improving the quality of melons can be conducted by developing improved hybrid varieties based on heterosis phenomenon. This study aimed to identify the potential melon genotypes with good fruit quality and evaluate the characters of the hybrids. The research was conducted in a greenhouse at the Cikabayan Experimental Station of the IPB University, Bogor from November 2020 to March 2021 and in an open field in Tanjungsari Village, Jogorogo, Ngawi, East Java from April to July 2021. The genetic materials for the first experiment were IPB G30, IPB G1, IPB M23, IPB M21, and one commercial hybrid variety as a check (Alisha F1). The genetic materials for the second experiment were 13 hybrid genotypes: H1, H2, H3, H4, H6, H7, H8, H9, H10, H11, H12, H13, H14; four parental genotypes: IPB G1, IPB G30, IPB M21, IPB M23; and Alisha F1 as a check. The first experiment was arranged using a single factor randomized complete block design (RCBD), while a single factor alpha lattice design was used for the second experiment. The H4 hybrid had good fruit traits, while H9 had good flesh color and taste, and ideal fruit size. The H7, H10, and H14 hybrids had the highest mid parent and best parent heterosis. The IPB M23 and IPB G30 had the potential to be used as parents for breeding improved varieties.
Keyword: heterosis, hibridisasi, kualitatif, kuantitatif, varietas hibrida

Judul: Metrik Einstein (Anti-) Self-Dual Berdimensi Empat dengan Metode Cartan
Abstrak: Gravitational field equation can be formulated in differential forms (differential geometry), which describes gravity as a manifestation of the curvature of space-time. Curvature of space-time is characterized by a metric that satisfies the gravitational field equation. With differential forms it can be formulated the (anti-) self-dual Einstein equation, which is a modification of the Cartan structure in (anti-) self-dual basis. Calculation of (anti-) self-dual metric with (anti-) self-dual Einstein equation is simpler than the calculation using Christoffel symbols.
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