Cotton(Gossypium spp.) is an important fiber and oil crop grown worldwide. Water and nutrient stresses are major issues affecting cotton production globally. Root traits are critical in improving water and nutrient up...Cotton(Gossypium spp.) is an important fiber and oil crop grown worldwide. Water and nutrient stresses are major issues affecting cotton production globally. Root traits are critical in improving water and nutrient uptake and maintaining plant productivity under optimal as well as drought conditions.However, root traits have rarely been utilized in cotton breeding programs, a major reason being the lack of information regarding genetic variability for root traits. The objective of this research was to evaluate ten selected cotton genotypes for root traits and water use efficiency. The tested genotypes included germplasm lines(PD 1 and PD 695) and cultivars that are currently grown in the southeastern USA(PHY 499 WRF, PHY 444 WRF, PHY 430 W3 FE, DP 1646 B2 XF, DP 1538 B2 XF, DP 1851 B3 XF, NG5007 B2 XF, and ST 5020 GLT). Experiments were conducted under controlled environmental conditions in 2018 and 2019. A hardpan treatment was included in the second year to evaluate the effect of a soil hardpan on root traits and water use efficiency. Genotype PHY 499 WRF ranked at the top and NG5007 B2 XF ranked at the bottom for root morphological traits(total and fine root length, surface area,and volume) and root weight. PHY 499 WRF was also one of the best biomass producers and had high water use efficiency. PHY 444 WRF, PHY 430 W3 FE, and PD-1 were the other best genotypes in terms of root traits and water use efficiency. All genotypes had higher values for root traits and water use efficiency under hardpan conditions. This trend indicates a horizontal proliferation of root systems when they incur a stress imposed by a hardpan. The genotypic differences identified in this research for root traits and water use efficiency would be valuable for selecting genotypes for cotton breeding programs.展开更多
Impertinent uses of moldboard plows for tillage on wetland paddy soils,as far more than a century,caused damage to its important hardpan layer of 20-30 cm soil depth that led to some extent,the decrease of rice produc...Impertinent uses of moldboard plows for tillage on wetland paddy soils,as far more than a century,caused damage to its important hardpan layer of 20-30 cm soil depth that led to some extent,the decrease of rice production than it should have been.The current study has been carried out to repair that damage to regain the“lost”of paddy yields by using the designed flat-symmetric plow that has a lift angle of 29°-30°.It is towed by a hand tractor of 12 horsepower(HP)at a travel speed of 1.11 m/s and a working depth of 10 cm in three blocks of a wetland paddy field in Bandung Sub-district of West-Java,Indonesia.Test results observed from the formed plow sole of 10-15 cm depth underneath after 3rd-time operations of the plow on the same track,indicated that there was a relatively small decrease of moisture content(MC)around 0.182%,as well as increases of cone index(CI)and bulk density(BD)around 0.172%and 0.171%,respectively.This plow was able to maintain,generate and stimulate the formation of hardpan right underneath the plow path.It was due to the improvement of hardpan physical-mechanical properties and would be more significant after frequent tillage using that plow.Hence,there is a chance to develop a tillage method in the development of an ideal wetland paddy cultivation system throughout Indonesian wetland paddy fields.展开更多
Understanding soil disturbance behaviors under the impact of the winged subsoiler is critical for designing or optimizing the winged subsoiler(a primary subsoiling tool).In this study,a soil-winged subsoiler interacti...Understanding soil disturbance behaviors under the impact of the winged subsoiler is critical for designing or optimizing the winged subsoiler(a primary subsoiling tool).In this study,a soil-winged subsoiler interaction model was developed and the effects of winged subsoiler on soil disturbance behaviors were investigated using the discrete element method(DEM)simulations and lab soil-bin tests.The results showed that wings mainly affected the disturbance range and fragmentation degree of soil above them.The draught forces of share section(SS),arc section in the hardpan(ASHP),arc section in the top layer(ASTL)and line section(LS)were accounted for 69.53%,25.22%,4.73%and 0.52%of the total draught force of winged subsoiler;the lateral disturbance range from high to low of the soil at different depths followed the ranking:top layer(TL),hardpan disturbed by arc section(HDAS)and hardpan disturbed by share section(HDSS).Wings had the greatest influence on the draught force of ASHP.Adding wings to an arc-shaped subsoiler increased the disturbance areas of HDAS,TL and HDSS by 47.52%,7.74%and 4.59%,respectively,but meanwhile increased the total draught force by 36%.Compared with a non-winged subsoiler,winged subsoiler had higher soil looseness(15.83%),soil disturbance coefficient(58.59%),furrow width(448.65 mm)and soil disturbance area ratio(0.3835),but poorer soil surface flatness(19.79 mm)and lower soil loosening efficiency(39.35 mm²/N).This study provided critical information for optimizing winged subsoilers on aspects of improving soil loosening effectiveness and reducing draught force.展开更多
基金the South Carolina Cotton Board and Cotton Incorporated for funding this project。
文摘Cotton(Gossypium spp.) is an important fiber and oil crop grown worldwide. Water and nutrient stresses are major issues affecting cotton production globally. Root traits are critical in improving water and nutrient uptake and maintaining plant productivity under optimal as well as drought conditions.However, root traits have rarely been utilized in cotton breeding programs, a major reason being the lack of information regarding genetic variability for root traits. The objective of this research was to evaluate ten selected cotton genotypes for root traits and water use efficiency. The tested genotypes included germplasm lines(PD 1 and PD 695) and cultivars that are currently grown in the southeastern USA(PHY 499 WRF, PHY 444 WRF, PHY 430 W3 FE, DP 1646 B2 XF, DP 1538 B2 XF, DP 1851 B3 XF, NG5007 B2 XF, and ST 5020 GLT). Experiments were conducted under controlled environmental conditions in 2018 and 2019. A hardpan treatment was included in the second year to evaluate the effect of a soil hardpan on root traits and water use efficiency. Genotype PHY 499 WRF ranked at the top and NG5007 B2 XF ranked at the bottom for root morphological traits(total and fine root length, surface area,and volume) and root weight. PHY 499 WRF was also one of the best biomass producers and had high water use efficiency. PHY 444 WRF, PHY 430 W3 FE, and PD-1 were the other best genotypes in terms of root traits and water use efficiency. All genotypes had higher values for root traits and water use efficiency under hardpan conditions. This trend indicates a horizontal proliferation of root systems when they incur a stress imposed by a hardpan. The genotypic differences identified in this research for root traits and water use efficiency would be valuable for selecting genotypes for cotton breeding programs.
文摘Impertinent uses of moldboard plows for tillage on wetland paddy soils,as far more than a century,caused damage to its important hardpan layer of 20-30 cm soil depth that led to some extent,the decrease of rice production than it should have been.The current study has been carried out to repair that damage to regain the“lost”of paddy yields by using the designed flat-symmetric plow that has a lift angle of 29°-30°.It is towed by a hand tractor of 12 horsepower(HP)at a travel speed of 1.11 m/s and a working depth of 10 cm in three blocks of a wetland paddy field in Bandung Sub-district of West-Java,Indonesia.Test results observed from the formed plow sole of 10-15 cm depth underneath after 3rd-time operations of the plow on the same track,indicated that there was a relatively small decrease of moisture content(MC)around 0.182%,as well as increases of cone index(CI)and bulk density(BD)around 0.172%and 0.171%,respectively.This plow was able to maintain,generate and stimulate the formation of hardpan right underneath the plow path.It was due to the improvement of hardpan physical-mechanical properties and would be more significant after frequent tillage using that plow.Hence,there is a chance to develop a tillage method in the development of an ideal wetland paddy cultivation system throughout Indonesian wetland paddy fields.
基金The authors gratefully acknowledge the financial assistance received from the National Key Research and Development Program of China(Grant No.2016YFD0200601,2016YFD020060101)and the Key Industry Chain Innovation Project of Shaanxi Province(Grant No.2018ZDCXL-NY-03-06).
文摘Understanding soil disturbance behaviors under the impact of the winged subsoiler is critical for designing or optimizing the winged subsoiler(a primary subsoiling tool).In this study,a soil-winged subsoiler interaction model was developed and the effects of winged subsoiler on soil disturbance behaviors were investigated using the discrete element method(DEM)simulations and lab soil-bin tests.The results showed that wings mainly affected the disturbance range and fragmentation degree of soil above them.The draught forces of share section(SS),arc section in the hardpan(ASHP),arc section in the top layer(ASTL)and line section(LS)were accounted for 69.53%,25.22%,4.73%and 0.52%of the total draught force of winged subsoiler;the lateral disturbance range from high to low of the soil at different depths followed the ranking:top layer(TL),hardpan disturbed by arc section(HDAS)and hardpan disturbed by share section(HDSS).Wings had the greatest influence on the draught force of ASHP.Adding wings to an arc-shaped subsoiler increased the disturbance areas of HDAS,TL and HDSS by 47.52%,7.74%and 4.59%,respectively,but meanwhile increased the total draught force by 36%.Compared with a non-winged subsoiler,winged subsoiler had higher soil looseness(15.83%),soil disturbance coefficient(58.59%),furrow width(448.65 mm)and soil disturbance area ratio(0.3835),but poorer soil surface flatness(19.79 mm)and lower soil loosening efficiency(39.35 mm²/N).This study provided critical information for optimizing winged subsoilers on aspects of improving soil loosening effectiveness and reducing draught force.
