A rational plant population is an important attribute to high yield of cotton, because it can provide a beneficial micro environment within the canopy for plant growth and development as well as yield formation. A 2-y...A rational plant population is an important attribute to high yield of cotton, because it can provide a beneficial micro environment within the canopy for plant growth and development as well as yield formation. A 2-yr field experiment was conducted to determine the optimal plant density based on cotton yield in relation to the canopy micro environment （canopy temperature, relative humidity and light transmittance）. Six plant densities （1.2-5.7 plants m^-2） were arranged with a completely randomized block design. The highest cotton yield （1 507 kg ha^-1） was obtained at 3.0 plants m^-2 due to more bolls per unit ground area （79 bolls m2）, while the lowest yield （1 091 kg ha1） was obtained at 1.2 plants m^-2. Under the moderate plant density （3.0 plants m^-2）, there was a lower mean daily temperature （MDT, 27. 1℃） attributing to medium daily minimum temperature （Train, 21.9℃） and the lowest daily maximum temperature （Tmax, 35.8℃）, a moderate mean canopy light transmittance of 0.51, and lower mean daily relative humidity （MRH） of 79.7% from June to October. The results suggest that 3.0 plants m^-2 would be the optimal plant density because it provides a better canopy micro environment.展开更多
N fertilization of 300 kg N ha-1 is normally applied to cotton crops in three splits： pre-plant application （PPA, 30%）, first bloom application （FBA, 40%） and peak bloom application （PBA, 30%） in the Yangtze Ri...N fertilization of 300 kg N ha-1 is normally applied to cotton crops in three splits： pre-plant application （PPA, 30%）, first bloom application （FBA, 40%） and peak bloom application （PBA, 30%） in the Yangtze River Valley China. However, low fertilizer N plant recovery （NPR） （30-35%） causes problems such as cotton yield stagnation even in higher N rate, low profit margin of cotton production and fertilizer release to the environment. Therefore, it is questioned： Are these three splits the same significance to cotton N uptake and distribution？ An outdoor pot trial was conducted with five N rates and 15 N labeled urea to determine the recovery and distribution of 15N from different splits in cotton （Gossypium hirsutum L. cv. Huazamian H318） plant. The results showed that, cotton plant absorbed fertilizer 15N during the whole growing period, the majority during flowering for 18-20 d regardless of N rates （150-600 kg ha-1）. Fertilizer 15N proportion to the total N accumulated in cotton plant increased with N rates, and it was the highest in reproductive organs （88% averaged across N rates） among all the plant parts. FBA had the highest NPR （70%）, the lowest fertilizer N lose （FNL, 19%）, and the highest contribution to the fertilizer 15N proportion to the total N （46%） in cotton plant, whereas PPA had the reverse effect. It suggests that FBA should be the most important split for N absorption and yield formation comparatively and allocating more fertilizer N for late application from PPA should improve the benefit from fertilizer.展开更多
Cotton yield per unit ground area has stagnated for a dozen years in Hubei Province, China, although a series of new high- yielding varieties have been commercialized. A multi-location investigation was carried out in...Cotton yield per unit ground area has stagnated for a dozen years in Hubei Province, China, although a series of new high- yielding varieties have been commercialized. A multi-location investigation was carried out in 2008 and 2009 in 13 counties to determine if increased planting population density （PPD） would break the stagnant yield. The results showed that significant differences among the fields existed in theoretical yield, PPD, and bolls per square meter （BPM）. The lowest yield of 1 641.1 kg ha-I was resulted from the lowest PPD of 1.7 plants m-2 and the lowest BPM of 71.8 bolls m-2, while the highest yield of 2 779.7 kg ha-~ was resulted from the highest PPD of 2.5 plants m-2, and the highest BPM of 129.4 bolls m-z. Plant mapping revealed that boll retention rate （BRR） was maintained over 30 or 40% for the first 17-18 fruiting branches （FBs） and decreased dramatically thereafter, rotten boll rate （RBR） decreased, but open boll rate （OBR） rose first and dropped later with rising FB from the bottom to the top. But BRR, RBR, and OBR were all dropped with the fruiting positions （FPs） extending outwards. The optimum range of plant density would be 2-3 plants m-2 and the proper individual plant structure would be 16-19 FBs with 5-7 FPs for cotton production in Hubei Province.展开更多
Cotton producers have substantially reduced their inputs(labor,nutrients,and management)mainly by adopting a shortseason cropping management that is characterized by late sowing,high density,and reduced fertilization ...Cotton producers have substantially reduced their inputs(labor,nutrients,and management)mainly by adopting a shortseason cropping management that is characterized by late sowing,high density,and reduced fertilization with one-time application at the first bloom stage without lint yield reduction.However,it has been hypothesized that one-time fertilization at an earlier growth stage could be a more effective and economic management practice.A two-year field experiment was conducted by applying five fertilizer one-time fertilization at 0(FT1),5(FT2),10(FT3),15(FT4),and 20(FT5)days after the first flower appeared in the field and one three-split fertilizer application taken as the conventional control(FT6),making six treatments altogether.Cotton growth period,biomass accumulation,yield,and its formation were quantified.The results showed that the one-time fertilization did not affect the cotton growth progress as compared to FT6,however,the total crop cycles for FT3–FT5 were 3 days shorter.FT1 produced the highest cotton lint yield(1396 kg ha–1),which was similar to the FT6 but higher than the other treatments,and could be attributed to more bolls per unit area and higher lint percentage.Cotton yield was positively correlated with cotton plant biomass accumulated.FT1 had both the highest average(VT)(193.7 kg ha–1 d–1)and the highest maximum(VM)(220.9 kg ha–1 d–1)rates during the fast biomass accumulation period.These results suggest that one-time fertilizer application at the first flower stage might be an adjustment that is more effective than at first bloom,and allowed for easier decision making for application date due to non counting of plants with flowers is needed.展开更多
基金supported by Special Fund for Agro-scientific Research in the Public Interest,China(3-5-19)the Modern Agro-Industry Technology Research System,China(Cotton 2007-2010)the National Transgenic Cotton Production Program,China(2009ZX08013-014B)
文摘A rational plant population is an important attribute to high yield of cotton, because it can provide a beneficial micro environment within the canopy for plant growth and development as well as yield formation. A 2-yr field experiment was conducted to determine the optimal plant density based on cotton yield in relation to the canopy micro environment （canopy temperature, relative humidity and light transmittance）. Six plant densities （1.2-5.7 plants m^-2） were arranged with a completely randomized block design. The highest cotton yield （1 507 kg ha^-1） was obtained at 3.0 plants m^-2 due to more bolls per unit ground area （79 bolls m2）, while the lowest yield （1 091 kg ha1） was obtained at 1.2 plants m^-2. Under the moderate plant density （3.0 plants m^-2）, there was a lower mean daily temperature （MDT, 27. 1℃） attributing to medium daily minimum temperature （Train, 21.9℃） and the lowest daily maximum temperature （Tmax, 35.8℃）, a moderate mean canopy light transmittance of 0.51, and lower mean daily relative humidity （MRH） of 79.7% from June to October. The results suggest that 3.0 plants m^-2 would be the optimal plant density because it provides a better canopy micro environment.
基金supported by the Professional(Agricultural) Researching Project for Public Interests,China(3-5-19)the Modern Agro-Industry Technology Research System,China(Cotton2007-2010)the National Transgenic Cotton Production Program,China(2009ZX08013-014B)
文摘N fertilization of 300 kg N ha-1 is normally applied to cotton crops in three splits： pre-plant application （PPA, 30%）, first bloom application （FBA, 40%） and peak bloom application （PBA, 30%） in the Yangtze River Valley China. However, low fertilizer N plant recovery （NPR） （30-35%） causes problems such as cotton yield stagnation even in higher N rate, low profit margin of cotton production and fertilizer release to the environment. Therefore, it is questioned： Are these three splits the same significance to cotton N uptake and distribution？ An outdoor pot trial was conducted with five N rates and 15 N labeled urea to determine the recovery and distribution of 15N from different splits in cotton （Gossypium hirsutum L. cv. Huazamian H318） plant. The results showed that, cotton plant absorbed fertilizer 15N during the whole growing period, the majority during flowering for 18-20 d regardless of N rates （150-600 kg ha-1）. Fertilizer 15N proportion to the total N accumulated in cotton plant increased with N rates, and it was the highest in reproductive organs （88% averaged across N rates） among all the plant parts. FBA had the highest NPR （70%）, the lowest fertilizer N lose （FNL, 19%）, and the highest contribution to the fertilizer 15N proportion to the total N （46%） in cotton plant, whereas PPA had the reverse effect. It suggests that FBA should be the most important split for N absorption and yield formation comparatively and allocating more fertilizer N for late application from PPA should improve the benefit from fertilizer.
基金funded by the Professional (Agriculture) Researching Project for Public Benefit of Ministry of Agriculture,China (3-5)High-Yielding Promotion Project of Ministry of Agriculture,Chinathe National Industrial System Program of Modern Agriculture,China
文摘Cotton yield per unit ground area has stagnated for a dozen years in Hubei Province, China, although a series of new high- yielding varieties have been commercialized. A multi-location investigation was carried out in 2008 and 2009 in 13 counties to determine if increased planting population density （PPD） would break the stagnant yield. The results showed that significant differences among the fields existed in theoretical yield, PPD, and bolls per square meter （BPM）. The lowest yield of 1 641.1 kg ha-I was resulted from the lowest PPD of 1.7 plants m-2 and the lowest BPM of 71.8 bolls m-2, while the highest yield of 2 779.7 kg ha-~ was resulted from the highest PPD of 2.5 plants m-2, and the highest BPM of 129.4 bolls m-z. Plant mapping revealed that boll retention rate （BRR） was maintained over 30 or 40% for the first 17-18 fruiting branches （FBs） and decreased dramatically thereafter, rotten boll rate （RBR） decreased, but open boll rate （OBR） rose first and dropped later with rising FB from the bottom to the top. But BRR, RBR, and OBR were all dropped with the fruiting positions （FPs） extending outwards. The optimum range of plant density would be 2-3 plants m-2 and the proper individual plant structure would be 16-19 FBs with 5-7 FPs for cotton production in Hubei Province.
基金supported by the National Natural Science Foundation of China (31271665)the Pairing Program of Key Laboratory of Oasis Ecology Agriculture, Xinjiang Production and Construction Group with Eminent Scholars in Elite Universities, China (201601)
文摘Cotton producers have substantially reduced their inputs(labor,nutrients,and management)mainly by adopting a shortseason cropping management that is characterized by late sowing,high density,and reduced fertilization with one-time application at the first bloom stage without lint yield reduction.However,it has been hypothesized that one-time fertilization at an earlier growth stage could be a more effective and economic management practice.A two-year field experiment was conducted by applying five fertilizer one-time fertilization at 0(FT1),5(FT2),10(FT3),15(FT4),and 20(FT5)days after the first flower appeared in the field and one three-split fertilizer application taken as the conventional control(FT6),making six treatments altogether.Cotton growth period,biomass accumulation,yield,and its formation were quantified.The results showed that the one-time fertilization did not affect the cotton growth progress as compared to FT6,however,the total crop cycles for FT3–FT5 were 3 days shorter.FT1 produced the highest cotton lint yield(1396 kg ha–1),which was similar to the FT6 but higher than the other treatments,and could be attributed to more bolls per unit area and higher lint percentage.Cotton yield was positively correlated with cotton plant biomass accumulated.FT1 had both the highest average(VT)(193.7 kg ha–1 d–1)and the highest maximum(VM)(220.9 kg ha–1 d–1)rates during the fast biomass accumulation period.These results suggest that one-time fertilizer application at the first flower stage might be an adjustment that is more effective than at first bloom,and allowed for easier decision making for application date due to non counting of plants with flowers is needed.
