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设置4个种植密度(3.0、3.75、4.5、5.25万株·hm-2)和5种叶枝处理方式(不留叶枝、留1个叶枝、留2个叶枝、留3个叶枝、留全部叶枝),研究不同密度和叶枝数量对冀丰914皮棉产量、铃重、衣分及成铃数的影响。结果表明:不论果枝铃重还是叶枝铃重均随叶枝的增加而下降;总成铃数随密度的增加而增加。衣分与密度、叶枝数量无显著相关性。密度对皮棉产量有显著影响,叶枝数量对皮棉产量影响不显著。在不同叶枝条件下,皮棉产量的最高值出现在不同密度:不留叶枝条件下,密度5.25万株·hm-2时产量最高;留1～3叶枝,密度4.5万株·hm-2时产量最高;留全部叶枝时,2015年密度在3.75万株·hm-2皮棉产量最高,2016年密度在4.5万株·hm-2产量最高。在低密度(3.0万株·hm-2)时保留叶枝对产量有较好的补偿作用。冀丰914在4.5万株·hm-2密度下保留1～3个叶枝能获得较高产量。 相似文献
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不同播种方式对合丰50品质、产量及产量构成因子的影响 总被引：2，自引：1，他引：1
采用裂区试验设计研究了合丰50在不同播法和种植密度条件下的品质、产量及产量构成因子.结果表明:播法对品质、产量和所有产量性状的影响均不显著,其中穴播对产量、脂肪含量、单株荚数、单株粒数、单株粒重的正向效应均是最大的.密度对百粒重、脂肪含量均无显著影响,但对其它性状均有显著的影响.随密度增加,蛋白质含量逐渐增加,单株荚数、单株粒数和单株粒重逐渐减少;在不同密度处理下,26万株·hm-2、23万株·hm-2与20万株·hm-2之间产量差异显著,26万株·hm-2为合丰50高产的最佳密度. 相似文献
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以一熟春棉(鲁棉研37号)为对照,研究棉饲两熟模式下3种不同种植密度(7.5万株·hm-2、9.0万株·hm-2、10.5万株·hm-2)对早熟棉鲁棉532棉田周年产量和效益,及其生长发育、光合特性和土壤理化性状的影响,以期明确黄河三角洲盐碱地棉饲两熟模式下鲁棉532的适宜种植密度。结果表明,与一熟春棉相比,鲁棉532棉饲两熟模式虽然棉花产量降低9.1%,但周年总投入降低了8.0%,周年纯收益显著提高了67.5%;株高、单株果枝数、单株结铃数显著减少,但是单位面积总铃数与春棉相当;净光合速率、叶面积指数显著降低,透光率显著增加;土壤有机质和养分含量提高,土壤含盐量和pH降低,但与春棉差异不显著。棉饲两熟模式下,适当增大鲁棉532种植密度能显著提高群体光合生产能力,增加群体总铃数,从而提高籽棉产量和周年效益。当棉花密度为9.0万株·hm-2时,周年收益、籽棉产量、总铃数和光合速率显著提高,分别比7.5万株·hm-2、10.5万株·hm-2提高5.4%、4.5... 相似文献
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不同密度及整枝方式对棉花品种（系）产量的影响 总被引：4，自引：3，他引：1
为探索适宜黄河流域简化整枝的棉花品种（系）及其密度,采用裂区设计,以株型有明显差异的2个品种（sGK中3017和鲁棉研28）以及1个品系（YB60-2）为试验材料,研究其在4个种植密度（4.5万、9.0万、13.5万和18.0万株·hm－2）和2种整枝方式（常规整枝和简化整枝）下的产量变化。结果表明：在黄河流域,鲁棉研28在密度为4.5万～9.0万株·hm－2时、sGK中3017在密度为9.0万株·hm－2时,适于采用简化整枝。 相似文献
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不同种植密度对新疆棉花产量及纤维品质的影响 总被引：3，自引：0，他引：3
本研究旨在为新疆地区进一步探索提高棉花产量、降低生产成本、提高棉花机械化生产水平,提供可靠的科学依据。以新陆中76号为供试棉花品种,研究不同种植密度（7.5万、10.5万、15.0万、18.0万、22.5万、25.5万株·hm－2）对其农艺性状、产量及纤维品质的影响。结果表明：随着种植密度的增加,棉花生育期延长,株高与始果枝节位高度越高,单株主茎叶片数、果枝、蕾、花、铃越少,铃重越轻;棉花种植密度以15.0万株·hm－2,棉花的铃重、衣分、籽棉和皮棉产量最高,其次是18.0万株·hm－2;密度对纤维长度影响较小,高密度栽培时断裂比强度下降,马克隆值变小。早中熟棉花品种的种植密度在15.0万～18.0万株·hm－2之间为宜。 相似文献
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Textile fibers were obtained from secondary polyethylene terephtalate (PET) and its mixtures with primary PET at initial orientation of 18000–33000 %, rate of additional orientation drawing 3.5–6.5 times and temperature of thermal fixation 363–413 K. The fibers’ tensile strength was found to decrease and elongation at break to increase with the decrease of their linear density under the conditions of fibers formation. For the fibers based on polymer mixtures, the presence of oxidized fragments in the secondary PET limited the compatibility of the two polymers which resulted in deteriorated tensile properties. The linear density (4–16 dtex), tensile strength (30–50 cN/tex) and elongation at break (20–60 %) of the PET fibers obtained were close to these for the industrially produced polymer fibers. The values of the average diameter of the fibers formed and oriented under laboratory conditions allows classifying them between the fine and the coarse textile fibers which makes them suitable for the textile industry. 相似文献
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Gas-exchange characteristics of potato (Solanum tuberosum L.) canopies were determined with crop enclosures under condition of optimal water supply, during soil water depletion, and during recovery from drought-stress. The plants were grown under a rainshelter in large containers with 2-m2 surface area. Control plants received water throughout the growth period. In Expt. 1, transient drought was imposed by interrupting water supply completely for 22 days. During the 33-day period of drought treatment in Expt. 2, the stressed plants received half the amount of water that was given to the control plants (irrigations 2–3 times per week).
During soil water depletion, stomatal conductance of the canopy was reduced earlier and more than photosynthesis. This resulted in a lower internal carbon dioxide concentration in the leaves of stressed plants and a higher ratio between photosynthesis and stomatal conductance. The value of that ratio increased as soil water potential dropped.
Water-use efficiency ( ) increased during drought stress. The cultivar Bintje showed a larger ratio between photosynthesis and stomatal conductance of the canopy and a higher than cv. Saturna, both for optimal water supply and during drought stress.
Photosynthesis and conductance of the canopy started to recover immediately upon rewatering, even when relative values had declined to 20–30% during the preceding stress period. After release from stress, the leaves in the top layer of the canopy had a higher stomatal conductance in treated plants than in control plants. 相似文献
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《Journal of Crop Improvement》2013,27(1):313-324
Summary Arbuscular mycorrhizae were inoculated into phosphorus-deficient soil fertilized with either organic or chemical fertilizer with cucumber (Cucumis sativus L.) as the first crop and lettuce (Lactu-ca sativa L.) as the second crop but without additional fertilization and AM inoculation. AM increased dry matter and fruit yield of cucumber significantly in the unfertilized, organic-fertilized and P-deficient plants compared with the fully chemical-fertilized plants. AM inoculation increased the available phosphorus in plant and soil by around 30% for all treatments except for those chemically-fertilized. The rate of AM infection did not differ significantly among the fertilization treatments, but the infection intensity was higher in unfertilized, organic-fertilized and phosphorus-deficient treatments than chemical-fertilized treatment. The residual effects of AM-inoculated to cucumber were evident for lettuce in all pre-treatments that were unfertilized and un-inoculated for the second cropping. Without P-fertilization, neither crop could grow optimally even when the soil was inoculated with AM, suggesting that AM could not serve as a substitute for phosphorus fertilizer. However, the other beneficial effects of AM on crop growth and yield could not be fulfilled with phosphorus fertilizer. 相似文献
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2017—2018年,在同安镇粮食产能区示范推广水稻病虫害绿色防控与统防统治融合技术模式,取得了显著成效。融合技术示范区比常规区减少用药2~3次,用药量减少37.6%,防治成本降低400元/hm^2;水稻产量增加12.8%,收益增加2 835元/hm^2。 相似文献
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生物质能作物——甘薯开发利用现状及趋势 总被引：13，自引：0，他引：13
甘薯是世界上重要的粮食、饲料、工业原料及新型能源用块根作物，在我国乃至世界再生能源开发中起到重大作用，其分布地域广，适应性强，沙荒地、岗坡地均可种植。生物产量高，而且种植栽培容易。甘薯含淀粉15％～30％，晒干率20％～35％，世界各国以薯干或淀粉为原料生产乙醇有着悠久的历史。随着全球能源的日趋紧张，乙醇作为一种可再生的环保燃料．将快速步入全球成品油市场，在替代汽油供应方面起到越来越大的作用。各国正在推行或制定燃料乙醇计划，并着眼于生物燃料乙醇应用方案，认为甘薯可能是摆脱将来粮食和能源危机的“最后一张王牌”。 相似文献
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为明确春季调控措施对冬小麦生长发育和籽粒产量的影响,以冬小麦品种石新828为材料进行田间试验,4个处理分别为:起身期追全部氮肥(除基肥外,下同)并叶面喷多效唑(N1);起身期追2/3氮肥并喷多效唑+拔节期追1/3氮肥(N2);起身期追1/3氮肥+拔节期追2/3氮肥(N3);拔节期追全部氮肥(N4)。生育期间测定群体和个体生育特性,成熟期调查产量性状。结果表明,N1和N2处理小麦拔节期的总茎数、叶面积指数(LAI)和干物质积累量均显著高于N4和N3处理。孕穗期N4和N3处理小麦的总茎数、LAI和干物质积累量显著高于N1和N2处理。开花到成熟期各处理的总茎数、LAI和干物质积累量差异均不显著。孕穗期前,不同处理的株高差异不显著,孕穗期后,N4处理的株高最高,且显著高于N1处理。各处理基部节间直径和中上部节间长的差异不显著,N4处理基部第一节间长度显著大于其他处理。随追氮时期前移或前期施氮量增多,不孕小穗数减少,结实小穗和穗粒数增加,N1比N4处理不孕小穗数显著减少,结实小穗和穗粒数显著增多。N1处理小麦成熟期的千粒重最高,且显著高于N4处理。N1处理的籽粒产量最高,且显著高于N3和N4处理。起身期追氮配合多效唑调控,可以获得比拔节期追氮更高的穗粒数和千粒重,从而获得更高的产量。 相似文献
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施镁量和施镁方法对烤烟生长发育和烟叶产量的影响 总被引：4，自引：0，他引：4
采用盆栽试验，研究施镁量和施镁方法对烤烟生长发育和烟叶产量的影响，结果表明：适量施用镁肥，可以促进烟草的生长发育、改善其农艺学性状，影响烟株对其它营养元素的吸收与积累，提高烟叶产量，并能使烟叶N，P，K，Ca等营养元素含量更趋协调。随着施镁量的增加，烟叶中镁含量提高10．7％～71．4％，烤烟单株吸镁量、叶片叶绿素含量、干物质产量分别提高17．6％～115．4％，1．9％～23．ooA和6．3％～25．7％，而对烟叶含钾量没有明显影响。在镁比较缺乏的土壤上，镁肥作基肥施比叶面喷施的效果好，基肥施镁结合叶面喷镁的效果最佳；叶面喷镁，肥料用量少、成本低、见效快，是一种有效的镁肥施用方法；提高镁肥用量，施镁的效果更加显著。 相似文献