Nematode Population Changes and Forage Yields of Six Corn and Sorghum Cultivars

Authors

  • R. McSorley
  • R. N. Gallaher

Abstract

Two temperate corn (Zea mays) hybrids (Pioneer 3320 and Northrup King 508), two tropical corn cultivars (Pioneer X304C hybrid and Florida SYN-1 experimental open pollinated cultivar), the sorghum (Sorghum bicolor) x sudangrass (Sorghum sudanense) hybrid DeKalb SX-17, and the sorghum hybrid DeKalb FS25E were compared for effect on nematode densities and forage yield in three plantings (one single-crop and one double-crop system) in Florida. Final population densities of Meloidogyne incognita in the three plantings ranged from 0 to 13/100 cm³ soil on the two Sorghum spp. and were lower (P = 0.001) than those obtained on the corn cultivars (range 147 to 762/100 cm³ soil). Early planted temperate corn and sorghum generally gave higher forage yields than did tropical corn. As second crops in double-cropping systems, tropical corn cultivars generally produced greater yields than temperate corn hybrids did. At 35% dry matter, double crop forage corn yield ranged from 51.1 to 64.8 ton/ha, and sorghum ranged from 79.8 to 102.2 ton/ ha. Tropical corn, forage sorghum, and sorghum-sudangrass were profitably grown at all planting dates. Late summer planting of temperate corn was unprofitable. DeKalb SX-17 sorghum x sudangrass first crop plus the ratoon double crop gave the highest net return of $1,133/ha. Among the corn cultivars, Florida SYN-1 gave the highest double crop net return of $652/ha. Key words: corn, Criconemella ornata, Criconemella sphaerocephala, cropping systems, double cropping, Meloidogyne incognita, nematode, Paratrichodorus minor, Pratylenchus scribneri, Sorghum bicolor, sorghum-sudangrass, Zea mays.

Downloads

Published

1991-10-15

Issue

Section

Articles