Weed control is a crucial factor for maintaining establishment and herbage production in dwarf variety of late-heading type （DL） napiergrass （Pennisetum purpureum Schumach） in southern Kyushu, Japan. This study wa...Weed control is a crucial factor for maintaining establishment and herbage production in dwarf variety of late-heading type （DL） napiergrass （Pennisetum purpureum Schumach） in southern Kyushu, Japan. This study was aimed to verify the weeding-effect on dry matter （DM） production in the farm level and to examine the effect of several weed control, i.e. mixed sowing of annual setaria （abbreviated as S）, which has no regrowth ability after stem-elongation, paper-mulching （as P） and hand-weeding （as ＋W）, compared with no-weeding （as -W） on DM yield and quality of DL napiergrass in two years. Weed control practices significantly （P 〈 0.05） promoted several plant growth attributes in DL napiergrass, compared with no-weeding both in the farm and experimental levels. Paper-mulchidng （P-W or P＋S-W） had highest yields among several practices in both years. Setaria-sowing ha a partially mitigating effect of weed damage on DM production of DL napiergrass, while additive DM gain from setaria could compensate the yield decrease in DL napiergrass and reduce herbicide cost. Neither digestibility nor crude protein was affected by any weed control in either year. Thus, paper-mulching and annual setaria-sowing could be effective alternative practices for weed control of this species.展开更多
Background:Tall fescue is sensitive to sowing depth and,in the Pampas region of Argentina,its sowing is often delayed from autumn(average air temperature 18.5℃)to winter(average air temperature 10.0℃).Since tall fes...Background:Tall fescue is sensitive to sowing depth and,in the Pampas region of Argentina,its sowing is often delayed from autumn(average air temperature 18.5℃)to winter(average air temperature 10.0℃).Since tall fescue is sensitive to the sowing depth,and temperature determines the emergence period,this study aimed to evaluate the effect of sowing depth at different times on seedling emergence and herbage yield.Methods:Two field experiments were carried out in Pergamino,Buenos Aires province,Argentina,to evaluate a summer‐active tall fescue at two sowing times and five sowing depths.The emergence of seedlings and the herbage yield in the year of sowing were determined.Results:Seedling emergence was maximal when sown at 1.2–1.5 cm depth and at 230 growing degree days(GDD)in early autumn and 257 GDD in winter.In both years and sowing seasons,herbage yield was positively related to the number of seedlings at maximum emergence.Conclusions:No differences in seedling emergence were observed between the autumn and winter sowings,and the emergence of tall fescue was well explained by the thermal time.The concept of“critical depth”was determined as the sowing depth at which the greatest seedling emergence and forage yield are achieved.展开更多
文摘Weed control is a crucial factor for maintaining establishment and herbage production in dwarf variety of late-heading type （DL） napiergrass （Pennisetum purpureum Schumach） in southern Kyushu, Japan. This study was aimed to verify the weeding-effect on dry matter （DM） production in the farm level and to examine the effect of several weed control, i.e. mixed sowing of annual setaria （abbreviated as S）, which has no regrowth ability after stem-elongation, paper-mulching （as P） and hand-weeding （as ＋W）, compared with no-weeding （as -W） on DM yield and quality of DL napiergrass in two years. Weed control practices significantly （P 〈 0.05） promoted several plant growth attributes in DL napiergrass, compared with no-weeding both in the farm and experimental levels. Paper-mulchidng （P-W or P＋S-W） had highest yields among several practices in both years. Setaria-sowing ha a partially mitigating effect of weed damage on DM production of DL napiergrass, while additive DM gain from setaria could compensate the yield decrease in DL napiergrass and reduce herbicide cost. Neither digestibility nor crude protein was affected by any weed control in either year. Thus, paper-mulching and annual setaria-sowing could be effective alternative practices for weed control of this species.
基金Instituto Nacional de Tecnología Agropecuaria,Grant/Award Number:PNPA1126073。
文摘Background:Tall fescue is sensitive to sowing depth and,in the Pampas region of Argentina,its sowing is often delayed from autumn(average air temperature 18.5℃)to winter(average air temperature 10.0℃).Since tall fescue is sensitive to the sowing depth,and temperature determines the emergence period,this study aimed to evaluate the effect of sowing depth at different times on seedling emergence and herbage yield.Methods:Two field experiments were carried out in Pergamino,Buenos Aires province,Argentina,to evaluate a summer‐active tall fescue at two sowing times and five sowing depths.The emergence of seedlings and the herbage yield in the year of sowing were determined.Results:Seedling emergence was maximal when sown at 1.2–1.5 cm depth and at 230 growing degree days(GDD)in early autumn and 257 GDD in winter.In both years and sowing seasons,herbage yield was positively related to the number of seedlings at maximum emergence.Conclusions:No differences in seedling emergence were observed between the autumn and winter sowings,and the emergence of tall fescue was well explained by the thermal time.The concept of“critical depth”was determined as the sowing depth at which the greatest seedling emergence and forage yield are achieved.
