The growth, development and consumption of successive three generations of cotton bollworm, Helicoverpa armigera (Htibner), fed on cotton bolls grown under elevated CO2 (double-ambient vs. ambient) in open-top cha...The growth, development and consumption of successive three generations of cotton bollworm, Helicoverpa armigera (Htibner), fed on cotton bolls grown under elevated CO2 (double-ambient vs. ambient) in open-top chambers were examined. Significant decreases in protein, total amino acid, water and nitrogen content and increases in free fatty acid were observed in cotton bolls. Changes in quality of cotton bolls affected the growth, development and food utilization of H. armigera. Significantly longer larval development duration in three successive generations and lower pupal weight of the second and third generations were observed in cotton bollworm fed on cotton bolls grown under elevated CO2. Significantly lower fecundity was also found in successive three generations of H. armigera fed on cotton bolls grown under elevated CO2. The consumption per larva occurred significant increase in successive three generations and frass per larva were also significantly increased during the second and third generations under elevated CO2. Significantly lower relative growth rate, efficiency of conversion of ingested food and significant higher relative consumption rate in successive three generations were observed in cotton bollworm fed on cotton bolls grown under elevated CO2. Significantly lower potential female fecundity, larval numbers and population consumption were found in the second and third generations of cotton bollworm fed on cotton bolls grown under elevated CO2. The integrative effect of higher larval mortality rate and lower adult fecundity resulted in significant decreases in potential population consumption in the latter two generations. The results show that elevated CO2 adversely affects cotton bolls quality, which indicates the potential population dynamics and potential population consumption of cotton bollworm will alleviate the harm to the plants in the future rising CO2 atmosphere.展开更多
In order to explore systematically the physiological mechanism of high yield cotton ( Gossypium hirsutum L.) in Xinjiang, and further improve yield, the yield components were compared between three ecological regi...In order to explore systematically the physiological mechanism of high yield cotton ( Gossypium hirsutum L.) in Xinjiang, and further improve yield, the yield components were compared between three ecological regions. Boll number per plant was lower in South and North Xinjiang, but the harvested plant population were nearly 1.5 times higher than that in Nangong, so total boll numbers per unit area were greater in South and North Xinjiang. Weight per boll in south and north of Xinjiang was 5.896.50 g and 5.43 6.12 g respectively, 24 to 51% heavier than that in Nangong. The diurnal temperature difference between day and night was relatively greater in Xinjiang than in Nangong, benefitting the accumulation of photosynthetic product in bolls. The temperature difference and total hours of sunshine in boll period are the main reasons for cottons higher boll weight and yield in Xinjiang than in Nangong.展开更多
A boll infection caused by non-traditional cotton pathogens was first reported to occur in the southeastern U.S. Cotton Belt (year 2000) and has since spread to Texas causing significant yield losses. This study was a...A boll infection caused by non-traditional cotton pathogens was first reported to occur in the southeastern U.S. Cotton Belt (year 2000) and has since spread to Texas causing significant yield losses. This study was aimed towards investigating the verde plant bug (<em>Creontiades signatus</em>) link between interior boll disease in Texas, USA. Using glasshouse grown bolls, bacteria recovered from locules with disease symptoms from field-grown cotton bolls caged with the piercing-sucking <em>C. signatus</em> were analyzed for the capacity to inflict the disease. For pathogenicity testing, spontaneously generated rifampicin resistant (Rifr) variants were utilized to track the antibiotic resistant bacterium and deter growth of endophytic and contaminating bacteria. To simulate <em>C. signatus</em> feeding, a needle (31 gauge) was employed to inoculate bolls at 13 - 15 days after flower bloom. Bacterial suspensions ranged from 10<sup>1</sup> - 10<sup>6</sup> colony forming units/ml. Field infection symptoms were duplicated after two weeks of bacterial exposure. Infectious strains were best categorized as <em>Serratia marcescens</em> based on traditional carbon utilization and enzyme production testing, and a 99% nucleotide sequence identity of 16S ribosomal DNA. Putative <em>S. marcescens</em> representatives isolated from rotted bolls exposed to<em> C. signatus</em> were shown to reproduce field infection symptoms upon inoculation into greenhouse grown fruit. <em>Serratia</em> spp. can inflict disease in alfalfa, cucurbits, and sunflower. The presented data are the first to definitively show that a <em>Serratia</em> sp. has the capacity to infect cotton.展开更多
To optimize the spatial distribution of cotton bolls and to increase the yield,the relationship between yield components and boll spatial distribution was investigated among different Bt(Bacillus thuringensis)cotton v...To optimize the spatial distribution of cotton bolls and to increase the yield,the relationship between yield components and boll spatial distribution was investigated among different Bt(Bacillus thuringensis)cotton varieties.A five-year field experiment was conducted to reveal the reasons for the differences in lint yield and fiber quality across three Bt cotton varieties with different yield formations from 2013 to 2017.The lint yield of Jiman 169(the average yield from 2013-2017 was 42.2 g/plant)was the highest,i.e.,16.3 and 36.9%higher than Lumianyan 21(L21)and Daizimian 99B(99B),respectively.And the differences in boll weight among the three cultivars were similar to the lint yield,while the others yield components were not.So the increase in lint yield was mainly attributed to the enlargement in boll weight.However,the change in fiber quality was inconsistent with the lint yield,and the quality of L21 was significantly better than that of Jimian 169(J169)and 99B,which was caused by the diversity of boll spatial distribution.Compared with 99B,the loose-type J169 had the highest number of large bolls in inner positions;the tight-type L21 had a few large bolls and the highest number of lower and middle bolls.And approximately 80.72%of the lint yield was concentrated on the inner nodes in Jiman 169,compared with 77.44%of L21 and 66.73%of 99B during the five-year experiment.Although lint yield was significantly affected by the interannual changes,the lint yield of J169 was the highest and the most stable,as well as its yield components.These observations demonstrated the increase in lint yield was due to the increase in boll weight,and the large bolls and high fiber quality were attributed to the optimal distribution of bolls within the canopies.展开更多
Bt cotton hybrids require large supply of metabolites to support their greater boll load and commonly suffer from premature leaf senescence. A field experiment was conducted to study the nutritional status of Bt cotto...Bt cotton hybrids require large supply of metabolites to support their greater boll load and commonly suffer from premature leaf senescence. A field experiment was conducted to study the nutritional status of Bt cotton leaves during boll development stage and to evaluate the most profitable source of foliar fertilizers. Treatments included basal application of 0 and 60 kg·K2O·ha-1 as muriate of potash (MOP) in main plots and foliar spray treatments viz: 4 & 6 sprays of 2% potassium nitrate (Multi-K, 13-00-45), 4 & 6 sprays of NPK Blend (Polyfed, 19-19-19), 4 sprays of MOP, 4 sprays of MOP + urea (to supply same amount of N & K as in potassium nitrate) and unsprayed control in sub plots. The results revealed that only N and K contents of premature senesced leaves were below the sufficiency range for cotton sufficient levels of P, Fe, Mn, Zn and Cu were observed. Though the concentrations of N and K in both the petiole and leaf blade initially improved with foliar spray, N content declined below the unsprayed control at later stages. Basal application of MOP increased seed cotton yield by 19%. Four foliar sprays of KNO3, NPK, MOP and MOP + urea recorded yield increase in seed cotton yield of 22.8%, 22.4%, 18.5% and 24.5%, respectively over unsprayed control. Six sprays of KNO3 and NPK had no yield advantage over four sprays and rather proved economically less viable.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
This study investigates the statistical relationship between climatic variables and aspects of cotton production (G. barbadense), and the effects of climatic factors prevailing prior to flowering or subsequent to boll...This study investigates the statistical relationship between climatic variables and aspects of cotton production (G. barbadense), and the effects of climatic factors prevailing prior to flowering or subsequent to boll setting on flower and boll production and retention in cotton. The effects of specific climatic factors during both pre- and post-anthesis periods on boll production and retention are mostly unknown. Thus, an understanding of these relationships may help physiologists to determine control mechanisms of production in cotton plants. Evaporation, sunshine duration, relative humidity, surface soil temperature at 1800 h, and maximum air temperature, are the important climatic factors that significantly affect flower and boll production. The least important variables were found to be surface soil temperature at 0600 h and minimum temperature. There was a negative correlation between flower and boll production and either evaporation or sunshine duration, while that correlation with minimum relative humidity was positive. Higher minimum relative humidity, short period of sunshine duration, and low temperatures enhanced flower and boll formation.展开更多
A rise in cotton boll rot in south Texas has been generally associated with increased yield losses. Here, we measured boll rot incidence during two growing seasons (2011 and 2012) at a south Texas (Kleberg County) res...A rise in cotton boll rot in south Texas has been generally associated with increased yield losses. Here, we measured boll rot incidence during two growing seasons (2011 and 2012) at a south Texas (Kleberg County) research farm Variety Trial and in producer fields. The Variety Trial was conducted to compare boll rot susceptibility between five current cultivars. The commercial fields surveyed were located along the Coastal Bend (Wharton County) and Rio Grande Valley regions (Cameron and Willacy Counties). Bolls with evidence of external damage potentially inflicted by piercing-sucking insect vectors were dissected for disease detection and plated for microorganism isolation and characterization. Microbial isolates were putatively identified based on standard fatty acid methyl ester profile analysis. In the Variety Trial, the highest incidence of disease occurred in July for both growing seasons, and significant differences in susceptibility to boll rot between cultivars were determined (P Bacillus spp. as a potential and prevalent causative agent(s).展开更多
Cotton growth and development are determined and influenced by cultivars, meteorological conditions, and management practices. The objective of this study was to quantify the optimum of temperature-light meteorologica...Cotton growth and development are determined and influenced by cultivars, meteorological conditions, and management practices. The objective of this study was to quantify the optimum of temperature-light meteorological factors for seedcotton biomass per boll with respect to boll positions. Field experiments were conducted using two cultivars of Kemian 1 and Sumian 15 with three planting dates of 25 April (mean daily temperature (MDT) was 28.0 and 25.4°C in 2010 and 2011, respectively), 25 May (MDT was 22.5 and 21.2°C in 2010 and 2011, respectively), and 10 Jun (MDT was 18.7 and 17.9°C in 2010 and 2011, respectively), and under three shading levels (crop relative light rates (CRLR) were 100, 80, and 60%) during 2010 and 2011 cotton boll development period (from anthesis to boll open stages). The main meteorological factors (temperature and light) affected seedcotton biomass per boll differently among different boll positions and cultivars. Mean daily radiation (MDR) affected seedcotton biomass per boll at all boll positions, except fruiting branch 2 (FB2) fruting node 1 (FN1). However, its influence was less than temperature factors, especially growing degree-days (GDD). Optimum mean daily maximum temperature (MDTmax) for seedcotton biomass per boll at FB11FN3 was 29.9-32.4°C, and the optimum MDR at aforementioned position was 15.8-17.5 MJ m-2. Definitely, these results can contribute to future cultural practices such as rational cultivars choice and distribution, simplifying field managements and mechanization to acquire more efficient and economical cotton management.展开更多
基金Project supported by the National Basic Research Program(973)of China(No.2006CB102002)the Pilot Project of Knowledge Innovation Program of Chinese Academy of Sciences(No.KSCX2-YW-N-006)National Natural Science Foundation of China(No.30571253,30621003)
文摘The growth, development and consumption of successive three generations of cotton bollworm, Helicoverpa armigera (Htibner), fed on cotton bolls grown under elevated CO2 (double-ambient vs. ambient) in open-top chambers were examined. Significant decreases in protein, total amino acid, water and nitrogen content and increases in free fatty acid were observed in cotton bolls. Changes in quality of cotton bolls affected the growth, development and food utilization of H. armigera. Significantly longer larval development duration in three successive generations and lower pupal weight of the second and third generations were observed in cotton bollworm fed on cotton bolls grown under elevated CO2. Significantly lower fecundity was also found in successive three generations of H. armigera fed on cotton bolls grown under elevated CO2. The consumption per larva occurred significant increase in successive three generations and frass per larva were also significantly increased during the second and third generations under elevated CO2. Significantly lower relative growth rate, efficiency of conversion of ingested food and significant higher relative consumption rate in successive three generations were observed in cotton bollworm fed on cotton bolls grown under elevated CO2. Significantly lower potential female fecundity, larval numbers and population consumption were found in the second and third generations of cotton bollworm fed on cotton bolls grown under elevated CO2. The integrative effect of higher larval mortality rate and lower adult fecundity resulted in significant decreases in potential population consumption in the latter two generations. The results show that elevated CO2 adversely affects cotton bolls quality, which indicates the potential population dynamics and potential population consumption of cotton bollworm will alleviate the harm to the plants in the future rising CO2 atmosphere.
文摘In order to explore systematically the physiological mechanism of high yield cotton ( Gossypium hirsutum L.) in Xinjiang, and further improve yield, the yield components were compared between three ecological regions. Boll number per plant was lower in South and North Xinjiang, but the harvested plant population were nearly 1.5 times higher than that in Nangong, so total boll numbers per unit area were greater in South and North Xinjiang. Weight per boll in south and north of Xinjiang was 5.896.50 g and 5.43 6.12 g respectively, 24 to 51% heavier than that in Nangong. The diurnal temperature difference between day and night was relatively greater in Xinjiang than in Nangong, benefitting the accumulation of photosynthetic product in bolls. The temperature difference and total hours of sunshine in boll period are the main reasons for cottons higher boll weight and yield in Xinjiang than in Nangong.
文摘A boll infection caused by non-traditional cotton pathogens was first reported to occur in the southeastern U.S. Cotton Belt (year 2000) and has since spread to Texas causing significant yield losses. This study was aimed towards investigating the verde plant bug (<em>Creontiades signatus</em>) link between interior boll disease in Texas, USA. Using glasshouse grown bolls, bacteria recovered from locules with disease symptoms from field-grown cotton bolls caged with the piercing-sucking <em>C. signatus</em> were analyzed for the capacity to inflict the disease. For pathogenicity testing, spontaneously generated rifampicin resistant (Rifr) variants were utilized to track the antibiotic resistant bacterium and deter growth of endophytic and contaminating bacteria. To simulate <em>C. signatus</em> feeding, a needle (31 gauge) was employed to inoculate bolls at 13 - 15 days after flower bloom. Bacterial suspensions ranged from 10<sup>1</sup> - 10<sup>6</sup> colony forming units/ml. Field infection symptoms were duplicated after two weeks of bacterial exposure. Infectious strains were best categorized as <em>Serratia marcescens</em> based on traditional carbon utilization and enzyme production testing, and a 99% nucleotide sequence identity of 16S ribosomal DNA. Putative <em>S. marcescens</em> representatives isolated from rotted bolls exposed to<em> C. signatus</em> were shown to reproduce field infection symptoms upon inoculation into greenhouse grown fruit. <em>Serratia</em> spp. can inflict disease in alfalfa, cucurbits, and sunflower. The presented data are the first to definitively show that a <em>Serratia</em> sp. has the capacity to infect cotton.
基金supported by the National Natural Science Foundation of China (31601253)the Modern Agroindustry Technology Research System, China (SDAIT-03)the Natural Science Foundation of Shandong Province, China (ZR2016CQ20)
文摘To optimize the spatial distribution of cotton bolls and to increase the yield,the relationship between yield components and boll spatial distribution was investigated among different Bt(Bacillus thuringensis)cotton varieties.A five-year field experiment was conducted to reveal the reasons for the differences in lint yield and fiber quality across three Bt cotton varieties with different yield formations from 2013 to 2017.The lint yield of Jiman 169(the average yield from 2013-2017 was 42.2 g/plant)was the highest,i.e.,16.3 and 36.9%higher than Lumianyan 21(L21)and Daizimian 99B(99B),respectively.And the differences in boll weight among the three cultivars were similar to the lint yield,while the others yield components were not.So the increase in lint yield was mainly attributed to the enlargement in boll weight.However,the change in fiber quality was inconsistent with the lint yield,and the quality of L21 was significantly better than that of Jimian 169(J169)and 99B,which was caused by the diversity of boll spatial distribution.Compared with 99B,the loose-type J169 had the highest number of large bolls in inner positions;the tight-type L21 had a few large bolls and the highest number of lower and middle bolls.And approximately 80.72%of the lint yield was concentrated on the inner nodes in Jiman 169,compared with 77.44%of L21 and 66.73%of 99B during the five-year experiment.Although lint yield was significantly affected by the interannual changes,the lint yield of J169 was the highest and the most stable,as well as its yield components.These observations demonstrated the increase in lint yield was due to the increase in boll weight,and the large bolls and high fiber quality were attributed to the optimal distribution of bolls within the canopies.
文摘Bt cotton hybrids require large supply of metabolites to support their greater boll load and commonly suffer from premature leaf senescence. A field experiment was conducted to study the nutritional status of Bt cotton leaves during boll development stage and to evaluate the most profitable source of foliar fertilizers. Treatments included basal application of 0 and 60 kg·K2O·ha-1 as muriate of potash (MOP) in main plots and foliar spray treatments viz: 4 & 6 sprays of 2% potassium nitrate (Multi-K, 13-00-45), 4 & 6 sprays of NPK Blend (Polyfed, 19-19-19), 4 sprays of MOP, 4 sprays of MOP + urea (to supply same amount of N & K as in potassium nitrate) and unsprayed control in sub plots. The results revealed that only N and K contents of premature senesced leaves were below the sufficiency range for cotton sufficient levels of P, Fe, Mn, Zn and Cu were observed. Though the concentrations of N and K in both the petiole and leaf blade initially improved with foliar spray, N content declined below the unsprayed control at later stages. Basal application of MOP increased seed cotton yield by 19%. Four foliar sprays of KNO3, NPK, MOP and MOP + urea recorded yield increase in seed cotton yield of 22.8%, 22.4%, 18.5% and 24.5%, respectively over unsprayed control. Six sprays of KNO3 and NPK had no yield advantage over four sprays and rather proved economically less viable.
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.
文摘This study investigates the statistical relationship between climatic variables and aspects of cotton production (G. barbadense), and the effects of climatic factors prevailing prior to flowering or subsequent to boll setting on flower and boll production and retention in cotton. The effects of specific climatic factors during both pre- and post-anthesis periods on boll production and retention are mostly unknown. Thus, an understanding of these relationships may help physiologists to determine control mechanisms of production in cotton plants. Evaporation, sunshine duration, relative humidity, surface soil temperature at 1800 h, and maximum air temperature, are the important climatic factors that significantly affect flower and boll production. The least important variables were found to be surface soil temperature at 0600 h and minimum temperature. There was a negative correlation between flower and boll production and either evaporation or sunshine duration, while that correlation with minimum relative humidity was positive. Higher minimum relative humidity, short period of sunshine duration, and low temperatures enhanced flower and boll formation.
文摘A rise in cotton boll rot in south Texas has been generally associated with increased yield losses. Here, we measured boll rot incidence during two growing seasons (2011 and 2012) at a south Texas (Kleberg County) research farm Variety Trial and in producer fields. The Variety Trial was conducted to compare boll rot susceptibility between five current cultivars. The commercial fields surveyed were located along the Coastal Bend (Wharton County) and Rio Grande Valley regions (Cameron and Willacy Counties). Bolls with evidence of external damage potentially inflicted by piercing-sucking insect vectors were dissected for disease detection and plated for microorganism isolation and characterization. Microbial isolates were putatively identified based on standard fatty acid methyl ester profile analysis. In the Variety Trial, the highest incidence of disease occurred in July for both growing seasons, and significant differences in susceptibility to boll rot between cultivars were determined (P Bacillus spp. as a potential and prevalent causative agent(s).
基金supported by the National Natural Science Foundation of China (31471444,31401327)the Special Fund for Agro-scientific Research in the Public Interest of China (Impact of Climate Change on Agriculture Production,201203096)the Jiangsu Overseas Research and Training Program for University Prominent Young and Middle-aged Teachers and President,China (2016)
文摘Cotton growth and development are determined and influenced by cultivars, meteorological conditions, and management practices. The objective of this study was to quantify the optimum of temperature-light meteorological factors for seedcotton biomass per boll with respect to boll positions. Field experiments were conducted using two cultivars of Kemian 1 and Sumian 15 with three planting dates of 25 April (mean daily temperature (MDT) was 28.0 and 25.4°C in 2010 and 2011, respectively), 25 May (MDT was 22.5 and 21.2°C in 2010 and 2011, respectively), and 10 Jun (MDT was 18.7 and 17.9°C in 2010 and 2011, respectively), and under three shading levels (crop relative light rates (CRLR) were 100, 80, and 60%) during 2010 and 2011 cotton boll development period (from anthesis to boll open stages). The main meteorological factors (temperature and light) affected seedcotton biomass per boll differently among different boll positions and cultivars. Mean daily radiation (MDR) affected seedcotton biomass per boll at all boll positions, except fruiting branch 2 (FB2) fruting node 1 (FN1). However, its influence was less than temperature factors, especially growing degree-days (GDD). Optimum mean daily maximum temperature (MDTmax) for seedcotton biomass per boll at FB11FN3 was 29.9-32.4°C, and the optimum MDR at aforementioned position was 15.8-17.5 MJ m-2. Definitely, these results can contribute to future cultural practices such as rational cultivars choice and distribution, simplifying field managements and mechanization to acquire more efficient and economical cotton management.