Antennae are significant chemosensory and mechanosensory organs for insects and need careful maintenance.Bees use a pair of comb-like tools located on the forelimbs to brush and remove contaminants from their antennae...Antennae are significant chemosensory and mechanosensory organs for insects and need careful maintenance.Bees use a pair of comb-like tools located on the forelimbs to brush and remove contaminants from their antennae.We filmed antenna grooming in three different bee species and observed that all bees raise their heads while grooming their antennae.We conducted a study to examine the effects of the distinctive grooming apparatus,as well as the antenna’s material and structural characteristics,on grooming behavior in both free-head and constrained-head scenarios.Head-raising increases the grooming speed by 300%compared to the situation where the head is constrained.It allows the bees to scrape the antennae 5 times per second.In addition,we proposed a mechanical model based on the morphological data to determine that raising the head increases the contact force by 50%.These findings will facilitate the development of innovative approaches for cleaning extended structures featuring bristly surfaces.展开更多
[Objective] The study was conducted to optimize the operation parameters of water control equipment for deep-litter beddings. [Method] A four-factor three-level orthogonal design was adopted to optimize experimental t...[Objective] The study was conducted to optimize the operation parameters of water control equipment for deep-litter beddings. [Method] A four-factor three-level orthogonal design was adopted to optimize experimental temperature, stopping time of aeration, aeration time and aeration rate by 9 groups of experiments, so as to improve the water removal efficiency of adopted mixed and reduce operation energy consumption. [Result] The average water contents in the mixed bedding under 3 temperatures decreased by 4.58% ±2.91%, 13.17% ±3.77% and 10.8% ±7.72%, respectively; the highest water removal efficiency could be achieved under an experimental temperature at 45 ℃, stopping time of aeration of 15 min, aeration time of 7 min, and an aeration rate at 4 m^3/min, which formed the optimal factor combination mode of the operation parameter of the water control equipment; the effects of various experimental factors on water content in the bedding were in order of aeration ratetemperatureaeration timestopping time of aeration; and the effects of various experimental factors on water removal efficiency in the bedding were in order of temperatureaeration rateaeration timestopping time of aeration. [Conclusion] After the optimization of operation parameters of the water control equipment for the deep-litter bedding, water removal efficiency of the mixed bedding could be improved, and the operation energy consumption of the equipment could be reduced.展开更多
[Objective] The experiment was aimed to select effective and economical media for container seedling of triploid clones of Populus tomentosa that was carried out. [Method] The sandy loam, peat, perlite, vermiculite, r...[Objective] The experiment was aimed to select effective and economical media for container seedling of triploid clones of Populus tomentosa that was carried out. [Method] The sandy loam, peat, perlite, vermiculite, riversand, sludge were taken as media of hardwood cutting and survival rate, seedling height were taken as indexes to select media for container seedling of triploid clones of Populus tomentosa. [Result] Different mixedmedia had great influence on survival rates of container seedlings. Taking peat and vermiculite with the proportion of 5∶2 (M10) or peat ,vermiculite with the proportion of 7∶2 (M11) or sandy loam (M1) as media would generate higher cutting survival rate that was higher than 90.0%. There were significant differece in height increments of container seedlings. Taking sandy loam, peat and vermiculite with the proportion of 6∶2∶2(M5)or sandy loam (M1), seedling height of 60-days the seedling was over 37.0 cm. [Conclusion] According to cost analysis of nursery medium, the optimum medium for hardwood cuttings container seedling-raising of triploid clones of Populus tomentosa was sandy loam.展开更多
This study was conducted to investigate the effects of seedling raising modes on photosynthetic charactedsticsand grain yield under wheat straw returning. Four representative cultivars in Huaibei area were selected as...This study was conducted to investigate the effects of seedling raising modes on photosynthetic charactedsticsand grain yield under wheat straw returning. Four representative cultivars in Huaibei area were selected as test materials. By setting potted seedlings and carpet seedlings, the effects of different nursery meth- ods on the photosynthesis of rice at different growth stages in Huaibei area were investigated. Compared with carpet seedlings, the leaf area index of potted seedlings decreased at the maturation stage, but the dry weight of leaf shewed no significant difference.The SPAD of potted seedlings had an increasing trend after transplanting, but the SPAD increased differently according to cultivars. The net photosynthetic rate, stomatal conductance and transpiration rate of the leaves of pot seeding rice were significantly higher than those of carpet seedling rice on the 85^th d after transplanting. However, theintracellular CO2 concentration and water use efficiency of leaves had no significant differences between different ＇treatments. The results indicate that the photosynthetic capacity of flag leaves of pot seedling rice is stronger in early and middle stages, but the decay rate of photosynthetic function is slightly faster than carpet seedling rice, which might be the main reason for the rice yield of potted seedlings having no remarkable difference from carpet seedlings.展开更多
The effects of farming method, rice variety and seedling-raising method were studied on the population growth quality and grain yield of the mechanized transplanting rice by way of three-factor split plot design. The ...The effects of farming method, rice variety and seedling-raising method were studied on the population growth quality and grain yield of the mechanized transplanting rice by way of three-factor split plot design. The results showed that the no-tillage mechanical transplanting treatment was poorer than the conventional mechanical transplanting treatment in transplanting quality in general, but the former was similar to the latter in population growth quality. In regard to grain yield, the no-tillage mechanical transplanting treatment was lower than the conventional me- chanical transplanting treatment. Raising both pot-mat seedling and plastic-tray seedling did not make much difference in population growth and grain yield of mechanized transplanting rice, so both of the seedling-raising methods can be adopted according to practical conditions.展开更多
[Objective] This study aimed to investigate the optimal component of culti- vation medium for container seedling raising of Camellia oleifera. [Method] In the application of container nursery technology of Camellia ol...[Objective] This study aimed to investigate the optimal component of culti- vation medium for container seedling raising of Camellia oleifera. [Method] In the application of container nursery technology of Camellia oleifera grafting in emergent stocks, yellow clay soil, surface soil of pine forest, decomposed edible fungus, peat soil, dung and dirt were mixed by different proportions into five formulae as nursery substrates, with garden soil as the control, in order to investigate the influences of various substrates on the growth of annual Camellia oleifera container seedlings by using randomized block design based on variance analysis and multiple comparisons, and to screen the optimal substrate formula for container nursery of Camellia oleifera. [Result] The influences of different substrates on the transplanting survival rate, seedling height, basal diameter, height-diameter ratio and lateral root length of Camellia oleifera container seedlings were significantly different. Various growth indi- cators of Camellia oleifera container seedlings cultivated in the substrate containing 40% of yellow clay soil ＋ 15% of surface soil of pine forest ＋ 20% of decomposed edible fungus ＋ 20% of peat soil ＋ 5% of dung and dirt exceeded that of the control and other substrate formulae, which could be used as the optimal substrate formula for the container nursery of Camellia oleifera. [Conclusion] This study screened the optimal substrate formula for the container nursery of Camellia oleifera, which provided technical reference for the cultivation of Camellia oleifera container seedlings.展开更多
In order to control the spawning quality and improve the economic benefit of Apostichopus japonicus Selenka, the indoor temperature and light control methods were employed for artificial maturation, spawning and hatch...In order to control the spawning quality and improve the economic benefit of Apostichopus japonicus Selenka, the indoor temperature and light control methods were employed for artificial maturation, spawning and hatching of A. japonicus, and the larval survival rate, disease incidence rate and economic benefit were analyzed. The results showed that compared with those of conventional temperature-reared larvae, the survival rate of raised temperature-reared larvae was increased by 15.8%, the disease incidence rate was reduced by 10.2%, and the economic benefit was improved by 21.6%. These results will provide theoretical basis and technical support for the artificial breeding of A. japonicus.展开更多
[Objective] The aim was to promote nutrient cycling and utilization in the mountain＇s system combining fruits and poultry and to control non-point source pollution produced from swine raising and navel orange plantin...[Objective] The aim was to promote nutrient cycling and utilization in the mountain＇s system combining fruits and poultry and to control non-point source pollution produced from swine raising and navel orange planting in headwaters of Dongjiang River. [Method] The quantitative analysis was mainly conducted for the so called ＂raising by planting＂ which is about material cycle in ＂pig-methane-fruit-fish＂ model and energy cascade utilization, based on relationship between excreted amount by livestock and the utilized quantity in Xinlin Farm in Longtang Town, Dingnan County, Jiangxi Province. [Result] Considering N requirement by fruit trees, a navel orange orchard （1 mu） could support about 2.72 pigs, the equipped biogas pool （1.88 m3） could support 1 166.67 kg of duckweeds and a fish pond could support 25.57 grass carps. In contrast, a satsuma orchard （1 mu） could support about 1.96 pigs, the equipped biogas pool （1.35 m3） could support 841.53 kg duckweeds and the fish pond could support 18.44 grass carps. [Conclusion] The results provided scientific references for quantitative allocation of members in ＂pig-methane-fruit-fish＂ model when popularized in headwaters of Dongjiang River.展开更多
To study the organic substrates substitution for turf has certain significances and has become a hot research topic. The sources of organic substrates mainly concentrate in organic waste of agriculture and forestry, a...To study the organic substrates substitution for turf has certain significances and has become a hot research topic. The sources of organic substrates mainly concentrate in organic waste of agriculture and forestry, animal husbandry industrial wastes and municipal sludge and so on in China. In order to better explore and utilize organic substrates resources, the authors summed up the application of organic substrates of different sources to vegetable seedling raising. The re- sults showed that the organic substrate produced by traditional and advanced tech- nology had the characteristics of stability, strong buffer capacity, comprehensive nu- trition and a good environment for root growth, which could reduce the production cost, cultivate high quality seedling and benefit cyclic utilization of resources, and replace or partly replace the turf. The prospects for future research direction were discussed to provide references for research and development on organic vegetable seedling raising technology in China.展开更多
To identify a strategy for earlier sowing and harvesting of spring maize(Zea mays L.) in an alternative maize–maize double cropping system, a 2-year field experiment was performed at Quzhou experimental station of Ch...To identify a strategy for earlier sowing and harvesting of spring maize(Zea mays L.) in an alternative maize–maize double cropping system, a 2-year field experiment was performed at Quzhou experimental station of China Agricultural University in 2014 and 2015. A short-season cultivar, Demeiya number 1(KX7349), was used in the experiment. Soil temperature to 5 cm depth in the early crop growth stage, crop growth, crop yield, and water use of different treatments(plastic film-mulched raised bed(RF) and flat field without plastic film mulching(CK) in 2014; RF, plastic film-mulched flat field(FF), and CK in 2015)were measured or calculated and compared. Soil temperature in the film-mulched treatments was consistently higher than that in CK(1.6–3.5 °C in average) during the early growth stage. Crops in plastic film-mulched treatments used 214 fewer growing-degree days(GDDs) in 2014 and 262 fewer GDDs in 2015. In 2014, the RF treatment yielded 32.7%higher biomass than CK, although its 9.4% higher grain yield was not statistically significant. Also, RF used 17.9% less water and showed 33.1% higher water use efficiency(WUE) than CK. In 2015, RF and FF showed 56.2% and 49.5% higher yield, 15.0% and 4.5%lower water use(ET), and 63.4% and 75.7% higher WUE, respectively, than CK. RF markedly increased soil temperature in the early crop season, accelerated crop growth, reduced ET,and greatly increased crop yield and WUE. Compared with FF, RF had no obvious effect on crop growth rate, although soil temperature during the period between sowing and stem elongation was slightly increased. However, RF resulted in lower ET and higher WUE than FF. Effects of RF on soil water dynamics as well as its cost-effectiveness remain topics for further study.展开更多
The no-till seeders of various soil opener configurations have been shown to produce various soil physical responses in relation to soil and climate conditions, thus affecting crop performance in permanent raised beds...The no-till seeders of various soil opener configurations have been shown to produce various soil physical responses in relation to soil and climate conditions, thus affecting crop performance in permanent raised beds （PRB） systems. This is particularly important in arid Northwest China where large volumes of residue are retained on the soil surface after harvest. In Zhangye, Gansu Province, China, a field trial assessed the effects of three typical （powered-chopper, powered-cutter and powered-disc） PRB no-till seeders and one traditional seeder on soil disturbance, residue cover index, bulk density, fuel consumption, plant growth, and subsequent yield. In general, seedbed conditions and crop performance for PRB no- till seeders seeded plots were better than for traditional seeded plots. In PRB cropping system, the powered-chopper seeder decreased mean soil disturbance and increased residue cover index compared to powered-disc and -cutter seeders. However, the results indicated that soil bulk density was 2.3-4.8% higher, soil temperature was 0.2-0.6℃ lower, and spring wheat emergence was 3.2-4.7% less. This was attributed to greater levels of residue cover and firmer seedbeds. Spring maize and wheat performance in the powered-cutter and -disc treatments was better （non-significant） than powered- chopper treatment. So powered disc no-till seeder, which generally provided the best planting condition and the highest yield, appeared to be the suitable seeder in heavy residue cover conditions. Considering the precision requirements for soil disturbance and residue cover, the powered strip-chopping no-till seeder could be a suitable option for PRB cropping system in Northwest China. Although these results are preliminary, they are still valuable for the design and selection of no-till seeders for PRB cropping systems in arid Northwest China.展开更多
基金supported by the National Natural Science Foundation of China(grant No.T2422031 and No.51905556).
文摘Antennae are significant chemosensory and mechanosensory organs for insects and need careful maintenance.Bees use a pair of comb-like tools located on the forelimbs to brush and remove contaminants from their antennae.We filmed antenna grooming in three different bee species and observed that all bees raise their heads while grooming their antennae.We conducted a study to examine the effects of the distinctive grooming apparatus,as well as the antenna’s material and structural characteristics,on grooming behavior in both free-head and constrained-head scenarios.Head-raising increases the grooming speed by 300%compared to the situation where the head is constrained.It allows the bees to scrape the antennae 5 times per second.In addition,we proposed a mechanical model based on the morphological data to determine that raising the head increases the contact force by 50%.These findings will facilitate the development of innovative approaches for cleaning extended structures featuring bristly surfaces.
基金Supported by the Fund for Independent Innovation of Agricultural Sciences in Jiangsu Province(CX(13)3073)Jiangsu Science and Technology Support Program(BE2014-342-1)~~
文摘[Objective] The study was conducted to optimize the operation parameters of water control equipment for deep-litter beddings. [Method] A four-factor three-level orthogonal design was adopted to optimize experimental temperature, stopping time of aeration, aeration time and aeration rate by 9 groups of experiments, so as to improve the water removal efficiency of adopted mixed and reduce operation energy consumption. [Result] The average water contents in the mixed bedding under 3 temperatures decreased by 4.58% ±2.91%, 13.17% ±3.77% and 10.8% ±7.72%, respectively; the highest water removal efficiency could be achieved under an experimental temperature at 45 ℃, stopping time of aeration of 15 min, aeration time of 7 min, and an aeration rate at 4 m^3/min, which formed the optimal factor combination mode of the operation parameter of the water control equipment; the effects of various experimental factors on water content in the bedding were in order of aeration ratetemperatureaeration timestopping time of aeration; and the effects of various experimental factors on water removal efficiency in the bedding were in order of temperatureaeration rateaeration timestopping time of aeration. [Conclusion] After the optimization of operation parameters of the water control equipment for the deep-litter bedding, water removal efficiency of the mixed bedding could be improved, and the operation energy consumption of the equipment could be reduced.
基金Supported by National Key Technology R&D Program during the 11th Five-year Plan Period(2006BAD32B01)~~
文摘[Objective] The experiment was aimed to select effective and economical media for container seedling of triploid clones of Populus tomentosa that was carried out. [Method] The sandy loam, peat, perlite, vermiculite, riversand, sludge were taken as media of hardwood cutting and survival rate, seedling height were taken as indexes to select media for container seedling of triploid clones of Populus tomentosa. [Result] Different mixedmedia had great influence on survival rates of container seedlings. Taking peat and vermiculite with the proportion of 5∶2 (M10) or peat ,vermiculite with the proportion of 7∶2 (M11) or sandy loam (M1) as media would generate higher cutting survival rate that was higher than 90.0%. There were significant differece in height increments of container seedlings. Taking sandy loam, peat and vermiculite with the proportion of 6∶2∶2(M5)or sandy loam (M1), seedling height of 60-days the seedling was over 37.0 cm. [Conclusion] According to cost analysis of nursery medium, the optimum medium for hardwood cuttings container seedling-raising of triploid clones of Populus tomentosa was sandy loam.
基金Supported by Jiangsu Provincial Science and Technology Demonstration Project(BE2015312)National Rice Industry Technical System(CARS-01-59)~~
文摘This study was conducted to investigate the effects of seedling raising modes on photosynthetic charactedsticsand grain yield under wheat straw returning. Four representative cultivars in Huaibei area were selected as test materials. By setting potted seedlings and carpet seedlings, the effects of different nursery meth- ods on the photosynthesis of rice at different growth stages in Huaibei area were investigated. Compared with carpet seedlings, the leaf area index of potted seedlings decreased at the maturation stage, but the dry weight of leaf shewed no significant difference.The SPAD of potted seedlings had an increasing trend after transplanting, but the SPAD increased differently according to cultivars. The net photosynthetic rate, stomatal conductance and transpiration rate of the leaves of pot seeding rice were significantly higher than those of carpet seedling rice on the 85^th d after transplanting. However, theintracellular CO2 concentration and water use efficiency of leaves had no significant differences between different ＇treatments. The results indicate that the photosynthetic capacity of flag leaves of pot seedling rice is stronger in early and middle stages, but the decay rate of photosynthetic function is slightly faster than carpet seedling rice, which might be the main reason for the rice yield of potted seedlings having no remarkable difference from carpet seedlings.
基金Supported by National Science and Technology Innovation Program for High-yielding and High-efficiency Grain Crops(2013BAD07B13-02)Special Fund for Agro-scientific Research in the Public Interest(201303102)~~
文摘The effects of farming method, rice variety and seedling-raising method were studied on the population growth quality and grain yield of the mechanized transplanting rice by way of three-factor split plot design. The results showed that the no-tillage mechanical transplanting treatment was poorer than the conventional mechanical transplanting treatment in transplanting quality in general, but the former was similar to the latter in population growth quality. In regard to grain yield, the no-tillage mechanical transplanting treatment was lower than the conventional me- chanical transplanting treatment. Raising both pot-mat seedling and plastic-tray seedling did not make much difference in population growth and grain yield of mechanized transplanting rice, so both of the seedling-raising methods can be adopted according to practical conditions.
基金Supported by Natural Science Foundation of Hubei Province(2012FFC03101)~~
文摘[Objective] This study aimed to investigate the optimal component of culti- vation medium for container seedling raising of Camellia oleifera. [Method] In the application of container nursery technology of Camellia oleifera grafting in emergent stocks, yellow clay soil, surface soil of pine forest, decomposed edible fungus, peat soil, dung and dirt were mixed by different proportions into five formulae as nursery substrates, with garden soil as the control, in order to investigate the influences of various substrates on the growth of annual Camellia oleifera container seedlings by using randomized block design based on variance analysis and multiple comparisons, and to screen the optimal substrate formula for container nursery of Camellia oleifera. [Result] The influences of different substrates on the transplanting survival rate, seedling height, basal diameter, height-diameter ratio and lateral root length of Camellia oleifera container seedlings were significantly different. Various growth indi- cators of Camellia oleifera container seedlings cultivated in the substrate containing 40% of yellow clay soil ＋ 15% of surface soil of pine forest ＋ 20% of decomposed edible fungus ＋ 20% of peat soil ＋ 5% of dung and dirt exceeded that of the control and other substrate formulae, which could be used as the optimal substrate formula for the container nursery of Camellia oleifera. [Conclusion] This study screened the optimal substrate formula for the container nursery of Camellia oleifera, which provided technical reference for the cultivation of Camellia oleifera container seedlings.
文摘In order to control the spawning quality and improve the economic benefit of Apostichopus japonicus Selenka, the indoor temperature and light control methods were employed for artificial maturation, spawning and hatching of A. japonicus, and the larval survival rate, disease incidence rate and economic benefit were analyzed. The results showed that compared with those of conventional temperature-reared larvae, the survival rate of raised temperature-reared larvae was increased by 15.8%, the disease incidence rate was reduced by 10.2%, and the economic benefit was improved by 21.6%. These results will provide theoretical basis and technical support for the artificial breeding of A. japonicus.
基金Supported by "Control and Treatment of Water Pollution" in National Science and Technology Major Project of China (2009ZX07211-001)~~
文摘[Objective] The aim was to promote nutrient cycling and utilization in the mountain＇s system combining fruits and poultry and to control non-point source pollution produced from swine raising and navel orange planting in headwaters of Dongjiang River. [Method] The quantitative analysis was mainly conducted for the so called ＂raising by planting＂ which is about material cycle in ＂pig-methane-fruit-fish＂ model and energy cascade utilization, based on relationship between excreted amount by livestock and the utilized quantity in Xinlin Farm in Longtang Town, Dingnan County, Jiangxi Province. [Result] Considering N requirement by fruit trees, a navel orange orchard （1 mu） could support about 2.72 pigs, the equipped biogas pool （1.88 m3） could support 1 166.67 kg of duckweeds and a fish pond could support 25.57 grass carps. In contrast, a satsuma orchard （1 mu） could support about 1.96 pigs, the equipped biogas pool （1.35 m3） could support 841.53 kg duckweeds and the fish pond could support 18.44 grass carps. [Conclusion] The results provided scientific references for quantitative allocation of members in ＂pig-methane-fruit-fish＂ model when popularized in headwaters of Dongjiang River.
基金Supported by Standardization Committee of Shandong Provincial Department o Agriculture~~
文摘To study the organic substrates substitution for turf has certain significances and has become a hot research topic. The sources of organic substrates mainly concentrate in organic waste of agriculture and forestry, animal husbandry industrial wastes and municipal sludge and so on in China. In order to better explore and utilize organic substrates resources, the authors summed up the application of organic substrates of different sources to vegetable seedling raising. The re- sults showed that the organic substrate produced by traditional and advanced tech- nology had the characteristics of stability, strong buffer capacity, comprehensive nu- trition and a good environment for root growth, which could reduce the production cost, cultivate high quality seedling and benefit cyclic utilization of resources, and replace or partly replace the turf. The prospects for future research direction were discussed to provide references for research and development on organic vegetable seedling raising technology in China.
基金financially supported by the Special Fund for Agro-scientific Research in the Public Interest (No. 201103001)
文摘To identify a strategy for earlier sowing and harvesting of spring maize(Zea mays L.) in an alternative maize–maize double cropping system, a 2-year field experiment was performed at Quzhou experimental station of China Agricultural University in 2014 and 2015. A short-season cultivar, Demeiya number 1(KX7349), was used in the experiment. Soil temperature to 5 cm depth in the early crop growth stage, crop growth, crop yield, and water use of different treatments(plastic film-mulched raised bed(RF) and flat field without plastic film mulching(CK) in 2014; RF, plastic film-mulched flat field(FF), and CK in 2015)were measured or calculated and compared. Soil temperature in the film-mulched treatments was consistently higher than that in CK(1.6–3.5 °C in average) during the early growth stage. Crops in plastic film-mulched treatments used 214 fewer growing-degree days(GDDs) in 2014 and 262 fewer GDDs in 2015. In 2014, the RF treatment yielded 32.7%higher biomass than CK, although its 9.4% higher grain yield was not statistically significant. Also, RF used 17.9% less water and showed 33.1% higher water use efficiency(WUE) than CK. In 2015, RF and FF showed 56.2% and 49.5% higher yield, 15.0% and 4.5%lower water use(ET), and 63.4% and 75.7% higher WUE, respectively, than CK. RF markedly increased soil temperature in the early crop season, accelerated crop growth, reduced ET,and greatly increased crop yield and WUE. Compared with FF, RF had no obvious effect on crop growth rate, although soil temperature during the period between sowing and stem elongation was slightly increased. However, RF resulted in lower ET and higher WUE than FF. Effects of RF on soil water dynamics as well as its cost-effectiveness remain topics for further study.
基金financed by the National Natural Science Foundation of China (51175499)the Beijing Natural Science Foundation, China (6112015)the Australian Centre for International Agricultural Research (ACIAR)
文摘The no-till seeders of various soil opener configurations have been shown to produce various soil physical responses in relation to soil and climate conditions, thus affecting crop performance in permanent raised beds （PRB） systems. This is particularly important in arid Northwest China where large volumes of residue are retained on the soil surface after harvest. In Zhangye, Gansu Province, China, a field trial assessed the effects of three typical （powered-chopper, powered-cutter and powered-disc） PRB no-till seeders and one traditional seeder on soil disturbance, residue cover index, bulk density, fuel consumption, plant growth, and subsequent yield. In general, seedbed conditions and crop performance for PRB no- till seeders seeded plots were better than for traditional seeded plots. In PRB cropping system, the powered-chopper seeder decreased mean soil disturbance and increased residue cover index compared to powered-disc and -cutter seeders. However, the results indicated that soil bulk density was 2.3-4.8% higher, soil temperature was 0.2-0.6℃ lower, and spring wheat emergence was 3.2-4.7% less. This was attributed to greater levels of residue cover and firmer seedbeds. Spring maize and wheat performance in the powered-cutter and -disc treatments was better （non-significant） than powered- chopper treatment. So powered disc no-till seeder, which generally provided the best planting condition and the highest yield, appeared to be the suitable seeder in heavy residue cover conditions. Considering the precision requirements for soil disturbance and residue cover, the powered strip-chopping no-till seeder could be a suitable option for PRB cropping system in Northwest China. Although these results are preliminary, they are still valuable for the design and selection of no-till seeders for PRB cropping systems in arid Northwest China.
