Direct and Correlated Responses to Selection for Specific Leaf Weight in Reed Canarygrass1
- Anake Topark-Ngarm,
- I. T. Carlson and
- R. B. Pearce2
Substantial progress was made by one cycle of selection for high and low specific leaf weight (SLW) in the broadbased germplasm source NCRC1 of reed canarygrass (Phalaris arundinacea L.). In a space-planted test, populations derived from 48 high and 48 low selections from 1,016 plants of NCRC1 averaged respectively 11% higher and 10070 lower in SLW than NCRCI. Average estimates of realized heritability were 0.59 for high and 0.55 for low SLW, indicating a relatively large additive component of genetic variance for this trait. Changes in SLW were accompanied by changes in other leaf characteristics and agronomic components of forage yield. Compared with NCRCI, the high SLW population averaged 11070 greater in leaf thickness (LT), 9% higher in COx-exchange rate (CER), 21% higher in dry weight per tiller, 24070 lower in tiller number, and 2% higher in dry matter yield per plant. In contrast, the low SLW population avesaged 7% less, 7 and 8% lower, 16070 higher, and 2% lower than NCRCI in those traits, respectively. The low SLW population had the smallest phenotypic variance among plants within plots for all traits except tiller number and weight, with differences among populations being significant in five of 12 instances. Specific leaf weight was positively correlated with LT and CER within populations.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
Copyright © . .