Identification of parental inbred lines for use in stalk lodging resistant corn hybrids

English. In an attempt to improve the stalk strength of corn hybrids, several experiments were conducted to : 1. identify source populations of stalk lodging resistant inbred lines, 2. study the relationship between stalk crushing strength and combining ability for grain yield, 3. find the relationship of stalk crushing strength and other stalk characters which are relatively easier and cheaper to measure, and 4. evaluate the stalk strength of improved open pollinated varieties. Evaluations were made for 22 top cross hybrids of 11 inbred lines with 2 testers, 16 top cross hybrids of 8 inbred lines with 2 testers, 5 single cross hybrids of 5 parental inbred lines, and 7 improved open pollinated varieties. The results showed that MOSQA(S-H)C12 and MOSQB(S-H)C12 can be used as sources in the development of stalk lodging resistant inbred lines. Two inbred lines, i.e, CTP1/212 and S4/168 have high combining ability for stalk crushing strength. Selection for combining ability for either stalk crushing strength or stalk rind thickness and for grain yield are mutually beneficial. Combining ability for stalk rind thickness can be used as an additional or possibly alternative criterion of selection of inbred lines for stalk lodging resistance. Besides stalk crushing strength, other more easily measured stalk characters, i.e. stalk rind thickness and stalk weight, might be used as additional or alternative criteria in the selection of stalk lodging resistance. There are highly significant differences among the improved varieties tested for all stalk characters studied

Indonesian. Dalam usaha memperbaiki kekuatan batang jagung hibrida, dilakukan beberapa percobaan untuk 1. mendapatkan populasi sumber inbrida tahan rebah batang, 2. mengetahui hubungan antara kuat batang dan daya gabung untuk daya hasil, 3. mengetahui hubungan antara kuat batang dengan sifat-sifat batang lainnya yang dapat diukur dengan lebih mudah dan murah, dan 4. mengetahui kuat batang dan varietas-varietas unggul. Untuk mencapai maksud tersebut dilakukan evaluasi terhadap 22 hibrida silang puncak dari 11 inbrida dengan 2 penguji, 16 hibrida silang puncak dari 8 inbrida dengan 2 penguji 5 hibrida silang tunggal dari 5 inbrida tetua dan 7 varietas unggul bersari bebas. Hasil penelitian menunjukkan bahwa populasi MOSQA (S-H)C12 dan MOSQB(S-H)C12 dapat dipakai sebagai sumber di dalam pengembangan galur inbrida tahan rebah batang. Dua inbrida CTPI/212 dan S4/168, mempunyai daya gabung untuk kuat batang yang tinggi. Seleksi daya gabung untuk kuat batang atau untuk tebal kulit batang dan daya gabung untuk daya hasil saling menunjang. Daya gabung untuk tebal kulit batang dapat dipakai sebagai kriteria tambahan atau pengganti dalam seleksi inbrida