不同促控方法对棉种“三高”繁殖的影响

大面积棉种繁殖过程中,实际存在着多种促控方法。不同促控方法产量、产值、投入各不相同,经济效益有高有低。目前比较普遍的是多促多控或大促大控,施肥多,化控多,增加用工,增大成本,结果高产量不等于高质量,高投入却是低效益。针对棉种繁殖中实际存在的问题,我们进行五种不同促控方法的比较试验。通过     

抗虫棉多茎株型栽培技术研究

为探讨棉花高产简化栽培新途径,通过十年连续田间试验,对棉花株型调控技术、不同株型不同部位及叶枝的成铃质量、多茎株型适宜的种植密度及品种适应性进行了研究。结果表明：利用叶枝塑造的株型为多茎倒伞型,其株型调控技术是留叶枝早摘心,主茎12 台果枝打顶、叶枝7 月5 日（初花期）摘心处理籽棉产量最高,较其他处理增产9.0%~10.9%;叶枝成铃单铃重高于多茎株型及常规株型下部1~4 台果枝结铃单铃重,纤维品质无明显差异;多茎株型栽培适宜的密度适应范围是3.3 万株/hm2~5.1 万株/hm2;多茎株型品种适应性广,叶枝发达的杂交棉品种增产潜力更大。多茎株型栽培高产简化技术关键是：扩行距、适密度、留叶枝、早摘心。     

短季棉多茎株型密度适应性研究

以短季棉常规株型为对照 ,研究了多茎株型的密度适应性。结果表明 :在 5.2 5万～ 8.2 5万株 /hm2 范围内 ,随密度的增加产量提高 ,最大值是 6.75万株 /hm2 ,霜前籽棉产量 51 4 0 .5kg/hm2 ,比 8.52万株 /hm2 处理增产 1 7.1 % ,增产效果达较显著水平 ;密度与株型之间的互作效应不显著 ;但多茎株型与常规株型相比 ,三个不同密度处理分别增产 2 0 .4%、2 0 .2 %和 1 8.8% ,增产效果均达较显著水平 ,说明多茎株型是短季棉高产栽培的理想株型 ,密度的适应性强 ,适宜的密度范围为 5.2 5万～6.75万株 /hm2 ,在此密度条件下 ,叶枝均衡发育 ,群体干物质积累量高 ,具备形成高产的物质基础。     

种植密度对黎民518产量及农艺性状的影响

设置4个密度,研究种植密度对株型紧凑型玉米品种黎民518产量及农艺性状的影响。结果表明,黎民518鲜草产量和子粒产量的最佳适宜密度不同,鲜草产量的适宜密度高于子粒产量的适宜密度。随群体密度的增加黎民518刈割青贮时的绿叶片数、单株鲜重、穗长、穗行数、行粒数呈下降趋势;高密度下秃尖长、株高、穗位高、倒伏(折)率、瘤黑粉病病株率逐渐增加;高密度下千粒重降低;青贮生育期略有延长。在黄河三角洲地区,黎民518饲用夏播最佳适宜密度为7.50万株/hm~2。     

棉花品种的群体株高对种子产量影响的研究

品种与密度互作产量之间有显著差异,最能反映品种特征特性的是株型,反映株型的最好指标是株高。在一定生产水平和群体容量范围内,株高与密度呈明显的反相关。品种的群体株高不仅表现直观平面的量化指标(cm),同时可透视动态的立体内涵指标——果枝果节,两者对棉种产量的合理建成具有重要的影响。该文从950块3730公顷棉种繁殖田中随机任择100块,调查群体株高交叉配合的效应,探讨不同群体株高的配合适度及其最佳运筹点,以聚类和回归分析的方法加以验证。研究结果对大面积棉种高产、稳产、优质、高效繁殖具有切实可行的参考价值。     

不同密度对黑膜缓控释肥栽培玉米产量及性状的影响

为了探索玉米获得高产的适宜种植密度,采用6个不同密度水平的单因子随机区组田间试验,进行不同密度对玉米产量、株型性状和经济性状影响的比较研究。结果表明:玉米产量随着密度的增加呈先增加后降低的变化,以密度3 400株/667m2的产量较高640.76kg/667m2,平均增产达6.86%,增产达显著或极显著水平。玉米茎粗、穗粗、穗粒数、穗粒重均随着密度的增加而逐渐降低,秃尖长、空杆率均随着密度的增加而逐渐增加。不同密度对其余的6个性状的影响均较小。在贵州思南种植区域,玉米获得高产的移栽密度为3 400株/667m2。     

棉花系统调控技术探讨

本文作者在总结棉花生产实践的基础上，对棉花高产系统调控技术进行了探讨，并根据高产棉花株型结构和发育规律得出不同阶段的控制目标，即通过水控、肥控、化控及其它手段进行综合控制，使促控矛盾协调统一，以达到最佳的调控效果。     

春育夏栽棉产量构成因素与品质空间分布模型研究

采用五元二次旋转回归设计田间试验，通过建立各类数学模型的统计分析得出，力争公顷铃数、兼顾铃重，是获得高产的主攻方向。摸清了各产量因素间相互制约、此长彼消的变化规律与不同皮棉产量的产量结构指标。明确狠抓中下部果枝１～２果节内围优质铃、运用适期早栽、合理密植、肥促化控等综合农艺措施，是实现优质高产最佳产量结构的症结     

种植密度对鲜食粒豌豆产量构成因子的影响

为筛选鲜食粒豌豆‘云豌18号’在滇中不同海拔区域的最佳种植密度,为良种配套良法提供依据,采用回归模型分析3个不同海拔试点不同种植密度对鲜食粒豌豆产量及构成因子的影响。结果表明,不同种植密度与产量拟合曲线均呈开口向下的二次抛物线关系,产量随种植密度的增加先呈上升趋势,当种植密度达一定量时产量达最高值,在一定种植密度范围内产量保持相对稳定,之后产量随种植密度增加而下降。3个海拔试点产量保持相对稳定的种植密度范围均为33万～42万株/hm²,海拔1545 m试点最佳种植密度为42万株/hm²,海拔1770 m试点最佳种植密度为33万株/hm²,海拔1970 m试点最佳种植密度为37.5万株/hm²。     

沿海地区棉花品种的三优繁殖

沿海地区大面积棉种繁殖过程中常常出现几种不同的成铃情况:1.株型松散的品种如移裁后密度偏密、施肥量偏重、蕾期雨水偏多、化控塑型偏迟的中期旺长脱落严重,后期又贪青迟熟,结果是“两头大、中间小”,上部和下部伏前桃、晚秋桃结得多,中部和中上部伏桃、早秋桃结得     

密度对棉花产量及棉铃内部产量构成的影响

以杂交种中棉所75和常规种鲁棉研28为材料,从冠层、单株以及单铃内部几个不同层次深入研究了密度对产量及产量构成因子的影响。结果表明,密度显著影响棉花产量,且这种影响可追溯到单株,甚至单个棉铃内部的单个种子上。5.1万株和8.7万株·hm-2密度下皮棉产量无显著差异,但显著高于1.5万株·hm-2密度的产量。在该试验密度范围,随着密度增加,棉株上部果枝和外围果节的成铃率显著降低;铃重、单粒种子截面积和单铃内种子数随密度增加呈下降趋势;单粒种子上纤维质量与种子所处位置相关,在棉铃基部和中部其随密度变化差异较大。     

我国棉花轻简化栽培关键技术研究进展

棉花轻简化栽培是适应中国国情、提高棉花竞争力水平和棉花持续生产的重要技术途径。本文分析了当前我国棉花生产面临的主要问题,回顾了我国棉花轻简化栽培技术的形成和发展,总结了从播种(育苗移栽),到简化整枝、合理密植、简化施肥、植保、灌溉、到采收诸环节轻简化的关键技术;并对轻简化栽培的熟性和株型调控理论等进行了评述,提出了进一步完善和发展轻简化植棉技术,促进棉花持续生产的技术与理论研究设想。     

精量播种减免间定苗对棉花产量和产量构成因素的影响

间苗、定苗是黄河流域棉区十分普及却费工费时的棉田管理措施。通过精量播种减免间苗、定苗环节,将为黄河流域棉区棉花轻简化栽培提供新的技术途径。2011-2013年连续3年在山东省临清市、夏津县、惠民县和东营市4个地点,以常规播种保苗方式为对照,研究了精量播种保苗(播量11.25 kg hm–2,出苗放苗后不间苗、定苗)方式对棉花收获密度、籽棉产量和产量构成因素的影响。年份、地点和播种保苗方式对棉花收获密度、籽棉产量和铃数皆有显著的互作效应。12个点次(3年4个地点)中有10个点次精量播种保苗方式的收获密度达到4.5~8.5株 m–2,铃数和籽棉产量与常规播种保苗方式相当;2011年东营点和2012年惠民点精量播种保苗方式的密度分别只有3.53株 m–2和3.63株 m–2, 铃数比常规播种分别减少13.8%和9.7%,单铃重与各自的对照无显著差异,籽棉产量分别减少14.2%和5.5%。精量播种处理中2个点次减产的主要原因在于收获密度过低,导致铃数降低。通过提高播种质量确保较高的收获密度,精量播种减免间定苗能够实现省工节本不减产,可作为一项重要的简化栽培措施在黄河流域棉区推行。     

中国棉花副产品作为生物质能源利用的潜力评估

中国每年产生丰富的棉花副产品资源,包括棉秆和棉籽。棉秆和棉籽壳纤维素和木质素含量高,棉籽仁含油量高,是适宜的生物质能源原料。从1980年到2014年,棉花主产区向西北内陆的新疆扩展,而在黄河流域和长江流域的种植面积缩小,主要原因是植棉比较效益大幅下降。利用棉花副产品生产生物质能源,是既缓解中国能源压力又提高植棉效益的1个新途径。利用1980―2014年中国各省棉花种植数据,分析30多年来棉花种植的区域变化,估算棉花副产品的产量和作为生物质能源的发展潜力。2014年棉花副产品的理论产量为3244万t,其中棉秆2236万t,棉籽1008万t。利用棉秆和棉籽壳可以生产1084万t生物炭或1355万t生物油,棉籽仁经生物质能源转化后可生产152万t生物柴油。利用棉花副产品生产生物质能源产品(生物油和生物柴油),其能源潜力可达1000万t标准煤。在利用30%和50%的情况下,能源潜力分别达到300万t和500万t标准煤。棉花副产品的能源化利用及其产业化发展不仅能够一定程度上缓解中国能源供应压力,还能促进棉花产业的可持续发展和棉民增收。     

Effects of Planting Date on Sucrose Metabolism in the Leaf Subtending to Cotton Boll,Within-boll Yield Components and Fiber Quality

[Objective] The present study aimed to investigate how sucrose metabolism in the leaf subtending to cotton boll, within-boll yield components and fiber quality respond to varying planting dates. [Method] Two upland cotton lines A705 and A201 differing in cotton boll traits were field tested in 2016-2017. Two different planting dates were designed with early planting on April 12, 2016, and April 15, 2017, and late planting on May 6, 2016, and May 28, 2017, respectively. Dynamics of non-structural carbohydrates (sucrose, hexose, starch) and key sucrose metabolism enzymes in the leaf subtending to cotton boll were examined including vacuolar acid invertase, cell wall acid invertase, sucrose phosphate synthase and sucrose synthase. The differences between two planting dates were compared for within- boll yield components, fiber quality and sucrose metabolism related characteristics. [Result] Late planting lengthened the period of cotton boll maturation relative to early planting. Boll weight, seed mass per boll, seed index and fiber length were increased, and lint percentage and micronaire were decreased. Late planting reduced the activities of cell wall acid invertase and sucrose synthase responsible for sucrose degradation, and in turn led to the increment of sucrose concentration in the subtending leaves which might enhance the carbon supply to the opposite bolls. [Conclusion] Lower temperature due to late planting could contribute to the more full development of cotton bolls. Late planting is an alternative consideration in improvement of fiber quality in cotton cultural practices.     

Interaction of Plant Density with Mepiquat Chloride Affects Plant Architecture and Yield in Cotton

[Objective] The effect of planting density and mepiquat chloride (DPC) on cotton plant architecture, growth, yield, and quality at Anyang City, Henan Province, China, was studied. [Method] Field experiments with cotton variety Lumianyan 28 were conducted with five planting densities (15 000, 45 000, 75 000, 105 000, and 135 000 plants·hm^－2) and application of DPC at three concentrations (0, 195, and 390 g·hm^－2). [Result] Increasing cotton plant density resulted in increased internode length and plant height but also caused the decrease of inclination of fruiting branches and leaves as well as elevated dry matter allocation to leaves and fruiting branches, which led to a decrease in dry matter accumulation. Application of DPC reduced the azimuth angle of fruiting branches and plant height, but increased the insertion angle of fruiting branches with the main stem, leaf length, and petiole length. Planting density and DPC treatment showed a significant interaction on fruiting branch insertion angle, plant height, stem diameter, and dry matter allocation to fruits and leaves. The interaction of DPC and planting density had a complementary effect on the spatial distribution of cotton-yielding bolls. The final dry matter was highest (14 362 kg·hm^－2) at the planting density of 105 000 plant·hm^－2 and DPC application of 390 g·hm^－2, which resulted in the highest seed yield (3 257 kg·hm^－2). [Conclusion] For maximization of cotton yield and quality, a plant density of 75 000 to 105 000 plants·hm^－2 and DPC application of 195 to 390 g·hm^－2 in the Yellow River cotton-producing region is recommended. The results may help to optimize labor-saving cotton management and to generate a plant architecture suitable for mechanical harvesting in the Yellow River cotton-producing region.     

Effects of Cotton/Sesame Intercropping Patterns on Crop Growth and Yield

[Objective] Intercropping as an intensive planting method, could increase the utilization ratio of land and resources. The study aimed to explore the advantages and disadvantages of cotton/sesame intercropping, and then find out the best planting pattern of cotton/sesame intercropping. [Method] Equidistant row monocropping cotton (Tc₁), wide narrow row monocropping cotton (Tc₂) and monocropping sesame (Ts) were used as control. We designed three intercropping patterns as follows: 1-1 pattern (cotton row spacing was 80 cm, one row of sesame was planted in the two row spacing), 2-1 pattern (cotton grown in wide-narrow-row, one row of sesame was planted in the wide row spacing), and 2-2 pattern (cotton grown in wide-narrow-row, two rows of sesame were planted in the wide row spacing). The effects of different intercropping patterns on cotton/sesame yield, yield components, leaf area index dynamic change and dry matter accumulation were investigated. The land equivalent ratio was used as an index to assess the land use efficiency. [Result] The results showed that cotton/sesame yield were significantiy affected by different intercropping patterns. However, the seed cotton yield decreased only slightly in 2-1 intercropping pattern. Two years average showed that, the seed cotton yield, plant height, boll number of per plant and boll weight in 1-1 pattern were reduced by 17.3%, 7.9%, 19.7% and 7.9% compared with Tc₁, respectively. In the treatment of 2-2 model, which reduced by 16.4%, 5.81%, 14.8% and 6.2% in comparison with Tc_2. But in the intercropping systems, the mixed yield and comprehensive economic benefit of cotton and sesame were higher than those of cotton and sesame monoculture. The leaf area index of the group and the total amount of dry matter accumulation in unit area increased significantly under cotton/sesame intercropping systems. The land equivalent ratios in 2015 and 2016 were from 1 to 1.24 and 0.91 to 1.16, respectively. [Conclusion] Under different cotton/sesame intercropping systems, the mixed yield and total economic benefit were higher than that of monocropping cotton or sesame. The 2-1 cotton/sesame intercropping pattern occupied the most optimal production performance and easy to cultivate, which was the practicable intercropping patterns in sustainable development.     

海南冬季棉花生育期分析

采用124个陆地棉品种(系),于2004-2005年冬季在海南岛三亚进行了4个播期的自然生育期试验。结果显示,全生育期平均为132.75 d,与我国主产棉区相差不大。不同播期之间全生育期相差较明显,以10月1-2日的第一播期最短,11月16-20日的第三播期最长,两者相差约15 d。冬繁棉花,早熟与中熟品种的全生育期相差不大(不到5 d),与棉区差异悬殊。就是在12月初播种,两个熟性的品种在4月中旬都能够完成自然生育期。根据试验结果,作者提出了冬繁棉花的“凹型生长模式”,并发现在后期播种的各个生育阶段,生育期的调节存在“缓冲”或“补偿”作用。根据凹型模式,作者提出科研南繁和产业南繁最佳播种期是10月,而抢季南繁在12月初播种亦可成功,并认为控制生育期的关键是在生长速度“低谷”时期。     

棉花短季直播栽培模式对产量构成及纤维品质的影响

为探索棉花短季直播高产栽培技术模式,2014年在湖南农业大学浏阳试验基地,采用"311"最优回归设计方案研究了播期、密度和施氮量对早熟品种JX0010的产量构成及纤维品质的影响。对不同处理的棉铃时空分布、棉花产量及纤维品质的分析结果表明:不同处理棉铃时间分布上以秋桃比例最大,空间分布上纵向分布以中下部成铃数所占比例大,横向分布以内围铃为主。根据结果,建立了3个栽培因子施氮量(x1)、密度(x2)、播种期(x3)与子棉产量的多项式回归方程:y=213.522+3.9331x1+6.414x2-21.4619x3-5.7541x12-4.321x22-7.5348x32~(-1)1.982x1x2-0.1645x1x3+3.5747x2x3。分析回归方程得出,单因子效应表现为播种期密度施氮量,交互作用表现为施氮量与密度的互作效应密度与播种期的互作效应施氮量与播种期的互作效应,根据回归方程得到子棉高产的最佳组合为施氮量202.35 kg·hm-2、密度6.20万株·hm-2、播种期5月19日,产量为5510.25 kg·hm-2。棉花纤维品质性状受影响的顺序为马克隆值断裂伸长率断裂比强度上半部平均长度长度整齐度指数。