共查询到18条相似文献,搜索用时 93 毫秒
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鲁棉研28号生育特点和对密度适应性研究 总被引:4,自引:2,他引:2
以曾在山东大面积种植的美国Bt抗虫棉33B为对照,于2005、2006年分别在山东临清和夏津研究了不同密度条件下国审Bt抗虫棉新品种鲁棉研28的生长发育和产量形成特点。两年观察结果表明,鲁棉研28的生育期与对照33B相当,但平均收获期比33B短1.7天,铃重、衣分和棉柴比显著高于33B,皮棉单产也显著提高,2005、2006年分别比33B增产22.2%和18.4%。33B在5.25~6.75株/m2密度时的产量最高,而鲁棉研28在4.75~6.75株/m2的密度范围内产量则没有变化。分析认为,抗虫棉新品种鲁棉研28号彻底解决了早期抗虫棉品种存在的铃小、衣分低、产量潜力小等不足,表现出产量构成协调、产量潜力大、适应性强等特点。 相似文献
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3个不同株型玉米适宜密度的研究 总被引:3,自引:0,他引:3
以当地3个不同类型的主栽玉米品种为试材,在7种不同种植密度条件下,研究了种植密度对3个玉米品种农艺性状和产量的影响。结果表明:随着种植密度的提高,穗长、穗粗、行数、行粒数、千粒重逐渐减小,秃尖长、株高和穗位高逐渐增加,生育期略有延长;平展型品种正大999的适宜种植密度为4.8万~5.4万株/hm2,半紧凑型品种正大619的适宜种植密度为5.4万株/hm2,紧凑型品种玉美头105的适宜种植密度为5.4万~6.0万株/hm2。 相似文献
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《农业科学学报》2016,(7)
Yield and fiber quality of cotton even varies within locules in a boll, but it is not clear how yield components and quality parameters are altered across seed positions of a locule(SPL). A field experiment was arranged in a split plot design with transgenic insect resistant Bt(Bacillus thuringiensis) cotton hybrid cultivar CRI75 and conventional cultivar SCRC28 as the main plots, and three plant densities(15 000, 51 000 and 87 000 plants ha–1) as the subplots in 2012 and 2013 at Anyang, Henan Province, China. Cotton was hand harvested by node and fruiting position, and then seeds of the first fruiting position bolls from nodes 6–10 were separated by SPL. The effects of plant density on lint yield, fiber quality, especially across SPL were determined. It was showed that plant densities of 51 000 and 87 000 plants ha–1 increased lint yield by 61.3 and 65.3% in 2012 and 17.8 and 15.5% in 2013 relative to low plant density(15 000 plants ha–1), however, no significant difference was observed between 51 000 and 87 000 plants ha–1. The number of bolls(boll density) increased while boll weight decreased as plant density raised, and no significant changes occured in lint percentage in 2013 but increased with plant density in 2012. The number of bolls in upper nodes and distal fruiting positions, the number of seeds per boll, seed area(SA) and seed vigor index increased with decreasing plant density. Seed area was found to be greater from the base to the middle compared to the apex of a locule. Mote frequency(MF) increased as plant density increased, and fiber quality was the best at the middle of the locule regardless of plant density. As the number of fibers per seed area is genetically determined, adjusting plant density to produce more seeds and greater seed area can be a potentially promising alternative to improve lint yield in cotton. These findings might be of great importantance to cotton breeding and filed management. 相似文献
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甘肃耐密玉米品种种植密度研究 总被引:1,自引:0,他引:1
研究了陇单3号、先玉335、郑单958在甘肃的种植密度效应,分析了各个品种在不同密度下的穗部性状及产量构成因素。结果表明:陇单3号的适宜栽培密度为82500株/hm2,在此密度下产量为20319.75kg/km2,穗粒数625粒、千粒重392g;先玉335的适宜栽培密度为90000株/hm2,在此密度下产量为19494.00kg/km2,穗粒数601粒、千粒重343.6g;郑单958的适宜栽培密度为90000株/hm2,在此密度下产量为16173.00kg/km2,穗粒数568粒、千粒重359.1g。分析结果还表明,各穗部性状中,随着密度的增加秃尖变长,其余性状的结果随着密度的增加都在降低。 相似文献
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Effects of plant density and nitrogen rate on cotton yield and nitrogen use in cotton stubble retaining fields
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Shi-hong WANG Li-li MAO Jia-liang SHI Jun-jun NIE Xian-liang SONG Xue-zhen SUN 《农业科学学报》2021,20(8):2090-2099
Increasing nitrogen(N) rate could accelerate the decomposition of crop residues, and then improve crop yield by increasing N availability of soil and N uptake of crops. However, it is not clear whether N rate and plant density should be modified after a long period of cotton stubble return with high N rate. This study seeks to assess the effects of N rate and plant density on cotton yield, N use efficiency, leaf senescence, soil inorganic N, and apparent N balance in cotton stubble return fields in Liaocheng, China, in 2016 and 2017. Three plant densities 5.25(D_(5.25)), 6.75(D_(6.75)) and 8.25(D_(8.25)) plants m~(-2) and five N rates 0(N_0), 105(N_(105)), 210(N_(210)), 315(N_(315)), and 420(N_(420)) kg ha~(-1) were investigated. Compared to the combination used by local farmers(D_(5.25) N_(315)), a 33.3% N reduction and a 28.6% increase in plant density(D_(6.75) N_(210)) can maintain high cotton yield, while a 66.7% N reduction at 6.75 plants m~(-2)(D_(6.75) N_(105)) can only achieve high yield in the first year. Biological yield increased with the increase of N rate and plant density, and the highest yield was obtained under 420 kg N ha~(-1) at 8.25 plants m~(-2)(D_(8.25) N_(420)) across the two years under investigation. Compared to D_(5.25) N_(315), N agronomic efficiency(NAE) and N recovery efficiency(NRE) in D_(6.75) N_(210) increased by 30.2 and 54.1%, respectively, and NAE and NRE in D_(6.75) N_(105) increased by 104.8 and 88.1%, respectively. Soil inorganic N decreased sharply under 105 kg N ha~(-1), but no change was found under 210 kg N ha~(-1) at 6.75 plants m~(-2). N deficit occurred under 105 kg N ha~(-1), but it did not occurr under 210 kg N ha~(-1) at 6.75 plants m~(-2). Net photosynthetic rate and N concentration of leaves under N rate ranging from 210 to 420 kg ha~(-1) were higher than those under N rate of 0 or 105 kg N ha~(-1) at all three densities. The findings suggest that D_(6.75) N_(210) is a superior combination in cotton stubble retaining fields in the Yellow River Valley and other areas with similar ecologies. 相似文献