| Abstrakt: |
‘Nelson’ ryegrass is a newly released variety of annual ryegrass that will be used as a forage crop for grazing livestock in the southern USA. Nelson (Reg. No. CV‐257, PI 658137) Italian ryegrass (Lolium multiflorumLam.) was developed by the Texas Agricultural Experiment Station—now Texas AgriLife Research—as a forage‐type annual ryegrass. Plant breeding of Nelson was conducted at what is now the Texas AgriLife Research and Extension Center at Overton, Texas. Nelson is a tetraploid where 2n= 4x= 28 chromosomes. Nelson is an open‐pollinated three‐way cross from ryegrass breeding lines TXR2000‐T2, TXR2002‐T17, and the cultivar ‘Jumbo’. Both TX breeding lines were from ‘TAM 90’ germplasm that had its chromosome numbers doubled from 14 to 28. Adjacent rows, which were replicated, were grown in an isolation block and allowed to cross‐pollinate and produce seed. Subsequent generations were grown and selected for high forage‐yield potential and crown rust (caused by Puccinia coronateCorda) resistance at Beaumont, Texas. Seed from these populations was increased in Oregon and was later tested for forage yield across the southern USA. Nelson has high forage‐yield potential, good crown rust resistance, and good cold tolerance for the southeastern USA. Nelson is improved for forage yield potential compared with most commercial cultivars in East Texas. The predominant use is projected to be in overseeding warm‐season pastures for winter production of forage for grazing animals. Seed production of Nelson will be in Oregon. Nelson was tested as TXR2006‐T22 and released in 2009. |
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