The Vietnamese agricultural sector has experienced a dramatic structural change based on increased specialization in rice cultivation.However,small-scale rice-farmers have continued to grow multiple crops,especially i...The Vietnamese agricultural sector has experienced a dramatic structural change based on increased specialization in rice cultivation.However,small-scale rice-farmers have continued to grow multiple crops,especially in less developed provinces.While the literature advocates crop diversification for reasons of both economic and ecological sustainability,there lacks empirical evidence as to whether crop diversification brings efficiency and productivity gains to small farms.The present study is the first applications of the input-oriented stochastic distance function approach in estimating scale and scope economies using data of multi-crop farming households in Vietnam.We find strong evidence of product-specific economies of scale.Scope economies are also present for rice,vegetable,and other annual crop production.This suggests that crop diversification enhances efficiency and productivity.However,there still exists significant technical inefficiency in crop production,indicating opportunities to expand farm output at the existing level of inputs and technologies.More specifically,our empirical results indicate that it is desirable to expand vegetable and other annual crop production in mountainous areas while rice cultivation can be further expanded in delta and coastal regions.展开更多
Background:A pelleted diet containing camelina hay(CAMH)or camelina meal(CAMM)as a supplement along with a control pellet(CONT)diet formulated with commonly available feeds during summer was used to investigate an alt...Background:A pelleted diet containing camelina hay(CAMH)or camelina meal(CAMM)as a supplement along with a control pellet(CONT)diet formulated with commonly available feeds during summer was used to investigate an alternative pathway for sustainable meat production.Sustainable meat production was based on a simple estimation of income from meat produced versus feed costs if animals were fed for an extended period over summer compared to early slaughter at the beginning of summer.Eighty maternal composite wether lambs(Composite)based on Coopworth genetics and 80 pure Merino wether yearlings were divided into 10 groups within breed(n=8)using stratified randomisation based on liveweights.Following 1 week of adaptation to experimental diets,animals were fed experimental diets for up to10 weeks.Results:Animals were slaughtered after either 8,9 or 10 weeks of full feeding when the average liveweight of diet/genetic combination reached a weight appropriate for either‘heavy lamb’or‘heavy hogget’production,which occurred between 8 and 10 weeks of full feeding.There was no diet×breed interactions except for dressing percentage(DP),where Composite lambs fed the CAMH diet had the greatest DP(48.1±0.35)and the Merino yearlings fed the CAMM diet the lowest DP(45.8±0.33).Composite lambs gained 17.6–20.3 kg and Merino yearlings gained 10.7–12.9 kg liveweight.Based on their DP,this resulted in the production of approximately 8.3–9.5 kg additional carcass weight in Composites and 4.9–5.7 kg in Merinos,which in turn produced greater profit per Composite lamb and a small profit per Merino yearling.Conclusions:Composite lambs fed CAMM and CAMH had 5%greater carcass weights at slaughter compared to the CONT group,but dietary treatments did not change carcass weight of Merino yearlings at slaughter.The extended feeding approach offered the producer an estimated economic gain of AUD$20.00 to$25.00 when yearly average prices were used(Method 1)and AUD$40.00 to$47.70 when pre-and post-summer average prices were used(Method 2)per Composite lambs,but extra carcass gain did not result in the same profit per Merino yearling.Among the Composites,the profit for animals fed the CAMH and CAMM were AUD$2.75 to$4.50 greater than CONT group when full year average prices were applied while AUD$3.50 to$5.50 greater than CONT group when pre-and post-summer average prices were applied.However,we acknowledge a combination approach of extended feeding for a portion of animals already on ground and selling the remaining animals pre-summer with joining of additional ewes is the most likely strategy.Considering the scenario of extended feeding for 3 weeks,based on the growth rates observed for Composite lambs,if an additional 2 kg carcass weight per animal can be gained for 50%of the 22 million lambs slaughtered in Australia(=11 million animals),it would potentially supply an additional 22 million kg of lamb carcasses produced per annum.This is equivalent to producing an extra 1 million lamb carcasses per annum weighing 22 kg each.Feeding Composite lambs for an extended period and selling Merino yearlings pre-summer may be a good option due to faster growth rate of Composites that may help quick turn-over to market.展开更多
Background:Onion grass(Romulea rosea)is a common weed that infests native and improved pastures in the Mediterranean environments of southern Australia.It is a very challenging weed to control due to its distinctive g...Background:Onion grass(Romulea rosea)is a common weed that infests native and improved pastures in the Mediterranean environments of southern Australia.It is a very challenging weed to control due to its distinctive growth and survival mechanisms involving corms.Methods:Three glasshouse experiments were conducted in Australia to investigate the response of onion grass to defoliation and fertiliser application,the development and growth of onion grass corms and the chemical control of the weed in winter and spring.Results:Defoliating consistently to 1 cm above ground reduced corm weight by 84%compared with the control.Medium or high fertiliser application did not increase herbage mass of onion grass compared with the nonfertilised treatment.The corm weight of onion grass declined from Weeks 1 to 8 after emergence,remained at 53-60 mg dry matter(DM)corm−1 from Weeks 8 to 19 and then declined on average to 37mgDMcorm−1 up to Week 26 after emergence.New corms started to develop at Week 6 after emergence.A small proportion of the onion grass plants(7.5%)developed multiple new corms(3-6 corms)from a single old corm.The most effective herbicide control was a winter application of metsulfuron methyl or imazamox as an alternative product to protect clover.Conclusions:This study has identified the growth and development patterns of onion grass corms,how the plant responded to defoliation and fertiliser application and effective chemical control of this weed.These findings have significant practical implications for the improvement of onion grass-infested pastures.展开更多
基金the University of Economics Ho Chi Minh City,the German Research Foundation(DFG,funding No.DFG-FOR 756/1&2)the Open Access Fund of Leibniz University Hannover,Germany.
文摘The Vietnamese agricultural sector has experienced a dramatic structural change based on increased specialization in rice cultivation.However,small-scale rice-farmers have continued to grow multiple crops,especially in less developed provinces.While the literature advocates crop diversification for reasons of both economic and ecological sustainability,there lacks empirical evidence as to whether crop diversification brings efficiency and productivity gains to small farms.The present study is the first applications of the input-oriented stochastic distance function approach in estimating scale and scope economies using data of multi-crop farming households in Vietnam.We find strong evidence of product-specific economies of scale.Scope economies are also present for rice,vegetable,and other annual crop production.This suggests that crop diversification enhances efficiency and productivity.However,there still exists significant technical inefficiency in crop production,indicating opportunities to expand farm output at the existing level of inputs and technologies.More specifically,our empirical results indicate that it is desirable to expand vegetable and other annual crop production in mountainous areas while rice cultivation can be further expanded in delta and coastal regions.
基金support for this study was provided by The Victorian Department of Jobs,Precincts and Regions(Agriculture Victoria Research),Australia.
文摘Background:A pelleted diet containing camelina hay(CAMH)or camelina meal(CAMM)as a supplement along with a control pellet(CONT)diet formulated with commonly available feeds during summer was used to investigate an alternative pathway for sustainable meat production.Sustainable meat production was based on a simple estimation of income from meat produced versus feed costs if animals were fed for an extended period over summer compared to early slaughter at the beginning of summer.Eighty maternal composite wether lambs(Composite)based on Coopworth genetics and 80 pure Merino wether yearlings were divided into 10 groups within breed(n=8)using stratified randomisation based on liveweights.Following 1 week of adaptation to experimental diets,animals were fed experimental diets for up to10 weeks.Results:Animals were slaughtered after either 8,9 or 10 weeks of full feeding when the average liveweight of diet/genetic combination reached a weight appropriate for either‘heavy lamb’or‘heavy hogget’production,which occurred between 8 and 10 weeks of full feeding.There was no diet×breed interactions except for dressing percentage(DP),where Composite lambs fed the CAMH diet had the greatest DP(48.1±0.35)and the Merino yearlings fed the CAMM diet the lowest DP(45.8±0.33).Composite lambs gained 17.6–20.3 kg and Merino yearlings gained 10.7–12.9 kg liveweight.Based on their DP,this resulted in the production of approximately 8.3–9.5 kg additional carcass weight in Composites and 4.9–5.7 kg in Merinos,which in turn produced greater profit per Composite lamb and a small profit per Merino yearling.Conclusions:Composite lambs fed CAMM and CAMH had 5%greater carcass weights at slaughter compared to the CONT group,but dietary treatments did not change carcass weight of Merino yearlings at slaughter.The extended feeding approach offered the producer an estimated economic gain of AUD$20.00 to$25.00 when yearly average prices were used(Method 1)and AUD$40.00 to$47.70 when pre-and post-summer average prices were used(Method 2)per Composite lambs,but extra carcass gain did not result in the same profit per Merino yearling.Among the Composites,the profit for animals fed the CAMH and CAMM were AUD$2.75 to$4.50 greater than CONT group when full year average prices were applied while AUD$3.50 to$5.50 greater than CONT group when pre-and post-summer average prices were applied.However,we acknowledge a combination approach of extended feeding for a portion of animals already on ground and selling the remaining animals pre-summer with joining of additional ewes is the most likely strategy.Considering the scenario of extended feeding for 3 weeks,based on the growth rates observed for Composite lambs,if an additional 2 kg carcass weight per animal can be gained for 50%of the 22 million lambs slaughtered in Australia(=11 million animals),it would potentially supply an additional 22 million kg of lamb carcasses produced per annum.This is equivalent to producing an extra 1 million lamb carcasses per annum weighing 22 kg each.Feeding Composite lambs for an extended period and selling Merino yearlings pre-summer may be a good option due to faster growth rate of Composites that may help quick turn-over to market.
基金Department of Jobs,Precincts and Regions and the Glenelg-Hopkins Catchment Management,Victoria,Australia.
文摘Background:Onion grass(Romulea rosea)is a common weed that infests native and improved pastures in the Mediterranean environments of southern Australia.It is a very challenging weed to control due to its distinctive growth and survival mechanisms involving corms.Methods:Three glasshouse experiments were conducted in Australia to investigate the response of onion grass to defoliation and fertiliser application,the development and growth of onion grass corms and the chemical control of the weed in winter and spring.Results:Defoliating consistently to 1 cm above ground reduced corm weight by 84%compared with the control.Medium or high fertiliser application did not increase herbage mass of onion grass compared with the nonfertilised treatment.The corm weight of onion grass declined from Weeks 1 to 8 after emergence,remained at 53-60 mg dry matter(DM)corm−1 from Weeks 8 to 19 and then declined on average to 37mgDMcorm−1 up to Week 26 after emergence.New corms started to develop at Week 6 after emergence.A small proportion of the onion grass plants(7.5%)developed multiple new corms(3-6 corms)from a single old corm.The most effective herbicide control was a winter application of metsulfuron methyl or imazamox as an alternative product to protect clover.Conclusions:This study has identified the growth and development patterns of onion grass corms,how the plant responded to defoliation and fertiliser application and effective chemical control of this weed.These findings have significant practical implications for the improvement of onion grass-infested pastures.
