Meadow bromegrass (Bromus riparius Rehmann) is an important forage crop in Canada and the Intermountain West, but it has not been extensively evaluated in the northern Great Plains (NGP). Our objectives were to 1) eva...Meadow bromegrass (Bromus riparius Rehmann) is an important forage crop in Canada and the Intermountain West, but it has not been extensively evaluated in the northern Great Plains (NGP). Our objectives were to 1) evaluate meadow, smooth, and hybrid bromegrasses for forage production under intensive management in eastern South Dakota, and 2) evaluate the effect of selection for vigor in multiple environments on forage production of meadow bromegrass. Thirteen populations (7 meadow bromegrass, 5 hybrid bromegrass, and 1 smooth bromegrass) were evaluated for 4 yrs (2005-2007, 2009) at Brookings, SD. Biomass at anthesis was greater for smooth (6.75 Mg ha-1) than for meadow or hybrid brome (5.4 Mg ha-1) in 2005, but production at anthesis during 2006 and 2007 was similar for meadow and smooth bromegrass. Regrowth harvested during July and October 2005 and November 2006 was greater for meadow than smooth or hybrid bromegrass. Forage production at anthesis in 2009, after rest (i.e., no cutting) and fertilization in 2008, was 4.2 Mg ha-1 for meadow bromegrass compared with 3.3 Mg ha-1 and 2.6 Mg ha-1 for hybrid and smooth bromegrass, respectively. Smooth and hybrid bromegrasses had more leaves·tiller-1 than meadow bromegrass. After 6 yrs, meadow bromegrass had higher tiller density and greater potential for tolerating multiple harvests during a growing season than did smooth or hybrid bromegrass. Selection for vigor in multiple environments in North America resulted in experimental populations of meadow bromegrass with superior forage yield compared with ‘Fleet’ on marginal crop land in the northern Great Plains.展开更多
Background:This study investigated the effects of daughter tiller removal on parent tiller development in Lolium perenne.Methods:Plants of L.perenne were grown hydroponically to allow separation of roots by phytomer p...Background:This study investigated the effects of daughter tiller removal on parent tiller development in Lolium perenne.Methods:Plants of L.perenne were grown hydroponically to allow separation of roots by phytomer position on the tiller axis and allowed to form two daughter tillers.In Experiment 1,adult daughter tillers were excised and effects on subsequent main tiller growth were observed for 16 days,on average.In Experiment 2,the growth of main tillers with or without daughter tillers was compared over 90–100 days.Two cultivars,‘Alto’bred from New Zealand germplasm and‘Aberdart’bred from United Kingdom germplasm were tested.Results:Excision of adult daughter tillers reduced the dry weight of older roots at the base of parent tiller axes and accelerated new phytomer appearance.Preventing tillers from forming daughter tillers by new tiller excision resulted in increased individual leaf and root dry weight in tillers without daughter tillers.Conclusions:The data indicated that daughter tillers contributed substrate for root development of their parent tillers.The presence of daughter tillers reduced the size of their main tiller but greatly enhanced whole plant yield.展开更多
文摘Meadow bromegrass (Bromus riparius Rehmann) is an important forage crop in Canada and the Intermountain West, but it has not been extensively evaluated in the northern Great Plains (NGP). Our objectives were to 1) evaluate meadow, smooth, and hybrid bromegrasses for forage production under intensive management in eastern South Dakota, and 2) evaluate the effect of selection for vigor in multiple environments on forage production of meadow bromegrass. Thirteen populations (7 meadow bromegrass, 5 hybrid bromegrass, and 1 smooth bromegrass) were evaluated for 4 yrs (2005-2007, 2009) at Brookings, SD. Biomass at anthesis was greater for smooth (6.75 Mg ha-1) than for meadow or hybrid brome (5.4 Mg ha-1) in 2005, but production at anthesis during 2006 and 2007 was similar for meadow and smooth bromegrass. Regrowth harvested during July and October 2005 and November 2006 was greater for meadow than smooth or hybrid bromegrass. Forage production at anthesis in 2009, after rest (i.e., no cutting) and fertilization in 2008, was 4.2 Mg ha-1 for meadow bromegrass compared with 3.3 Mg ha-1 and 2.6 Mg ha-1 for hybrid and smooth bromegrass, respectively. Smooth and hybrid bromegrasses had more leaves·tiller-1 than meadow bromegrass. After 6 yrs, meadow bromegrass had higher tiller density and greater potential for tolerating multiple harvests during a growing season than did smooth or hybrid bromegrass. Selection for vigor in multiple environments in North America resulted in experimental populations of meadow bromegrass with superior forage yield compared with ‘Fleet’ on marginal crop land in the northern Great Plains.
基金supported by a‘Massey University Vice‐Chancellor's Doctoral Scholarship’and study leave from Bangladesh Agricultural University.
文摘Background:This study investigated the effects of daughter tiller removal on parent tiller development in Lolium perenne.Methods:Plants of L.perenne were grown hydroponically to allow separation of roots by phytomer position on the tiller axis and allowed to form two daughter tillers.In Experiment 1,adult daughter tillers were excised and effects on subsequent main tiller growth were observed for 16 days,on average.In Experiment 2,the growth of main tillers with or without daughter tillers was compared over 90–100 days.Two cultivars,‘Alto’bred from New Zealand germplasm and‘Aberdart’bred from United Kingdom germplasm were tested.Results:Excision of adult daughter tillers reduced the dry weight of older roots at the base of parent tiller axes and accelerated new phytomer appearance.Preventing tillers from forming daughter tillers by new tiller excision resulted in increased individual leaf and root dry weight in tillers without daughter tillers.Conclusions:The data indicated that daughter tillers contributed substrate for root development of their parent tillers.The presence of daughter tillers reduced the size of their main tiller but greatly enhanced whole plant yield.
