RELATIONSHIPS OF MATURITY, HEIGHT AND MORPHOLOGICAL TRAITS WITH WHOLE-PLANT YIELD AND DIGESTIBILITY OF BARLEY CULTIVARS

Abstract

Eight six-rowed barley (Hordeum vulgare L.) lines were used to study the relationship of whole-plant dry matter yield (WPY), whole-plant digestible yield (WPDY) and percent in vitro organic matter digestibility (IVDOM) with plant height, maturity, grain and leaf content at the time of maximum WPY. The study was conducted at Lacombe, Alberta during 1983 and 1984. Whole-plant harvests were initiated at the 50% heading stage of individual lines and continued for seven consecutive weeks. WPY and WPDY attained maximum levels at identical harvest times after heading in all lines and years. In 1983 all lines, and in 1984, six of eight lines attained maximum WPY at the same time postheading (fourth and third harvest in 1983 and 1984, respectively). WPY and WPDY were significantly correlated with days from planting to time of maximum yield (TMY) in both years. Partial coefficients of determination from stepwise multiple regression analyses indicated that the effect of days from planting until TMY > plant height > days to heading on WPY. The effect of days from planting until TMY > plant height > IVDOM > days to heading on WPDY, and the effect leaf content was more important than any other variable on IVDOM. It was concluded that late-maturing, tall barley lines having a high leaf content were most likely to produce high WPDY and hence be advantageous for utilization as whole-plant barley forage.Key words: Barley, whole-plant, digestibility, maturity, height