Abstract
Ten grain sorghum lines (Sorghum bicolor (L.) Moench) selected from the Conversion Program were evaluated at the Mayagüez Institute of Tropical Agriculture (MITA), Mayagüez, Puerto Rico. Grain yield among the 10 lines ranged from 910 to 4,153 kg/ha. Line 9, brown-seeded, was the highest producer. Days to mid-flower among the 10 lines ranged from 71.2 to 76.2. The high-yielding lines were late flowering. Height ranged from 83.5 to 117 cm. Weight of 10 seeds ranged from 1.63 to 2.81 g. Line 4, the lowest grain producer, had the heaviest seeds. Seed volume ranged from 1.21 to 2.20 cm3/100 seed. Line 4 had the highest volume. Density among the 10 lines ranged from 1.17 to 1.36 g/cm3. Lines 2 and 10 had the highest density. Insect damage caused by armyworms ranged from 3.3 to 4.9 (on a scale of 1 lowest to 9 highest) but no statistical differences were observed among them. Rust, the most prevalent disease observed, ranged from 0.8 to 3.8 on a scale of 1 lowest to 5 highest. The incidence of anthracnose was relatively low, ranging from 0.0 to 2.8. Zonate leaf spot ratings ranged from 0 .4 to 3.1. The mean incidence of leaf blight was relatively low, ranging from 0.1 to 1.5. A multiple correlation analysis showed no significant correlation among insect and disease attacks and total grain yield. It was shown that useful sorghum material, with variations in height and maturity, and with good yield potential and resistance to pests is available in the Conversion Program for direct utilization in the tropics.