Indonesian Journal of Agricultural Science Vol. 21 No. 1 June 2020: 11–16 DOI: http//dx.doi.org/10.21082/ijas.v.21.n1.2020.p.11–16 IMPROVE YIELD AND DOWNY MILDEW RESISTANCE OF F1 MADURA MAIZE HYBRIDS Perbaikan Hasil dan Ketahanan terhadap Penyakit Bulai pada Jagung Hibrida (F 1 ) Madura Achmad Amzeri * and Kaswan Badami Faculty of Agriculture, University of Trunojoyo Madura Bangkalan 69162, East Java, Indonesia. * Corresponding author: aamzeri@gmail.com Submitted 28 October 2019; Revised 03 March 2020; Accepted 02 June 2020 ABSTRACT Maize production in Madura Island is low. The study aimed to evaluate the agronomic performances (fowering age, harvesting age, and yield), heterosis efect, and resistance to downy mildew disease of F 1 Madura maize hybrids. Ten F 1 maize hybrids and seven respective parents were evaluated at the experimental center of the Agro-Technology Study Program of Agriculture Faculty, the University of Trunojoyo Madura, from July to December 2017. The experiments were arranged in a randomized block design, three replications, with a 50–100 plant population per unit. The parents were T 12 , T 16 , G 10 , G 14 , E 02 , Td 04 and L 1 genotypes having resistance to downy mildew (Peronosclerospora maydis). The results showed that the fowering age of the F 1 Madura maize hybrids ranged 35–39 days, the harvesting age was 74–81 days, and the yield ranged from 2.90–6.40 t ha -1 . Three hybrids showed the highest yield (T 12 x L 1 = 6.40 t ha -1 , T 16 x L 1 = 5.42 t ha -1 , and E 02 x L 1 = 5.90 t ha -1 ), and resistance to downy mildew, i.e. T 12 x L 1 (26.67%), T 16 x L 1 (26.67%), and E 02 x L 1 (26.67%). Two hybrids showed the highest heterosis values for yield, i.e. T 12 x L 1 (65.80%) and E 02 x L 1 (54.65%). The study suggests that three F 1 Madura maize hybrids (T 12 x L 1 , T 16 x L 1 and E 02 x L 1 ) are prospective to be developed further for high yield and resistance to downy mildew. [Keywords: agronomic character, heterosis value, Peronosclerospora maydis] ABSTRAK Produksi jagung di Pulau Madura tergolong rendah. Penelitian ini bertujuan untuk mengevaluasi karakter agronomis (umur berbunga, umur panen, dan hasil biji), efek heterosis, serta ketahanan terhadap penyakit bulai pada jagung hibrida (F 1 ) Madura. Sepuluh jagung hibrida (F 1 ) dan tujuh tetuanya dievaluasi di Kebun Percobaan Program Studi Agroteknologi Fakultas Pertanian, Universitas Trunojoyo Madura pada bulan Mei sampai Desember 2017. Percobaan menggunakan rancangan acak kelompok, tiga ulangan, dengan 50–100 populasi tanaman per unit percobaan. Tetua yang digunakan yaitu genotipe T 12 , T 16 , G 10 , G 14 , E 02 , Td 04 dan L 1 yang resisten terhadap bulai (Peronoclerospora maydis). Hasil penelitian menunjukkan bahwa umur berbunga jagung hibrida (F 1 ) Madura berkisar 35–39 hari, umur panen 74-81 hari, dan hasil biji 2.90–6.40 t ha -1 . Tiga hibrida F 1 menunjukkan hasil tertinggi, yakni T 12 x L 1 6.40 t ha -1 , T 16 x L 1 5.42 t ha -1 , dan E 02 x L 1 5.90 t ha -1 serta tahan terhadap penyakit bulai, yaitu T 12 x L 1 26.67%, T 16 x L 1 26.67%, dan E 02 x L 1 26.67%. Dua hibrida menunjukkan nilai heterosis tertinggi untuk hasil, yaitu T 12 x L 1 65.80% dan E 02 x L 1 54.65%. Penelitian ini menunjukkan bahwa tiga jagung hibrida (F 1 ) Madura (T 12 x L 1 , T 16 x L 1 , dan E 02 x L 1 ) dapat dikembangkan lebih lanjut untuk perakitan varietas yang mempunyai karakter hasil tinggi dan tahan terhadap penyakit bulai. [Kata kunci: karakter agronomis, nilai heterosis, Peronoslerospora maydis] INTRODUCTION Maize is one of important crops widely cultivated by farmers in Madura, East Java, Indonesia. The maize planting area in Madura is around 360,000 hectares (Amzeri 2018). But, maize yield in Madura is the lowest compared to other maize production centers in East Java. Maize yield at the farm level in Madura in 2016 was only 2 t ha -1 , while maize yield in East Java achieved 5.08 t ha -1 (Pusat Data dan Informasi Pertanian 2016; Amzeri 2018). The causes of the low yield of maize in Madura are: (1) less fertile land, (2) low rainfall, and (3) use of nonsuperior seeds (Amzeri 2009). The ways to solve these problems could be through (1) improving the environmental conditions in which the plant grows and develops, and (2) assembling a variety that is resistant to biotic or biotic environmental stresses and has a high yield potential through breeding programs. The second method is more popular than the frst one. The improved appearance of plants can be through the utilization of heterosis efect. The heterosis phenomenon is the action and interaction of good dominant genes collected in one F 1 genotype as a result of crossing two parents (Amzeri 2015). The use of heterosis in some food crops through the formation of hybrid varieties shows favorable results in cross-pollinating plants (Bairagi et al.