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充分利用热量资源是我国棉花生产和科研的关键 总被引：2，自引：0，他引：2
棉花原产热带,是喜温作物。温度是制约棉花生育进程的一个基本因素。一般中熟品种必须有≥10℃积温4200℃,无霜期210天,才能完成正常生长发育和结铃吐絮。从总体上看,在10～40℃范围内,温度每升高10℃, 相似文献
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汕优63制种中实效积温的应用及穗期预测数字模型的建立 总被引：2，自引：0，他引：2
提出了实效积温的概念，并确立了汕优６３制种生产中的父母本实效保的 间为１３－２６℃。根据扬州市红旗良种场３ａ的实践，以实效积温为主要依据 安排播差是可靠，的。还建立了实效积温为主要自变量预测父母本始穗期的数学模型。 相似文献
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热量条件变化对热带及亚热带作物生长发育都具有极大影响作用.利用漳州市10县市1961-2015年不小于10℃积温等气象资料,运用现代气候统计诊断技术,分析该地区农作物不小于10℃积温生长期、积温及其平均气温的变化特征及其相互间关系.结果表明,近55年来,漳州市不小于10℃积温生长期、积温及其平均气温都呈线性递增趋势,积温生长期和积温增加趋势显著目.两者相关显著,而平均气温上升趋势不显著,积温的增加主要由于积温生长期增长而增加.漳州市不小于10℃积温增长率大值区在其东部县市和西南部县(不小于10℃/a),呈现两翼分布,也是全市积温大值区;而华安县为积温递增率最小值区(不大于5℃/a),也是全市积温最小区.通过对漳州市农作物生长期热量变化分析,为进一步开发利用热量资源和种植业结构调整提供决策参考. 相似文献
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温度对水稻抗褐飞虱特性的影响 总被引：2，自引：0，他引：2
为研究温度对水稻抗褐飞虱特性的影响,于2007年和2008年应用苗期集团筛选法（SSST）在杭州地区的自然条件下测定了抗性水稻品种IR26和IR36对田间褐飞虱的抗性,同时比较了不同温度（22℃、25℃、28℃、31℃和34℃）下IR26和IR36对褐飞虱的抗性、可溶性糖和草酸含量的变化。自然条件下,IR26已完全失去对杭州种群褐飞虱的抗性,而IR36仍具中等抗性。在25℃到34℃的范围内随着温度升高,IR26对褐飞虱抗性减弱,但22℃条件下抗性比25℃更弱。IR36在温度升高的条件下对褐飞虱的抗性总体呈降低趋势,在31℃和34℃下也已完全失去对褐飞虱的抗性。在22~25℃条件下,IR26和IR36的持抗期均在25℃下最长,分别为9 d和11 d。3个品种稻株中的可溶性糖含量均随温度升高而增加,而草酸含量则随温度升高先增加后下降,在25℃时为最大值。不同温度下及不同水稻品种之间稻株内可溶性糖和草酸的含量均有显著差异。 相似文献
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吐鲁番盆地气候干旱,降水极少,无霜期长,光热资源丰富,是新疆优质棉产区,根据近10年吐鲁番盆地气象资料,该区从6月10日至10月10日历年≥10℃积温为山南2500～3500℃左右,平均3000 C,平均气温26℃,日较差15.7℃,山北积温2000～3000℃左右,平均2500℃,平均气温22.1℃.日较差17.3℃.从热量资源看,可以满足复播棉生长发育所需的条件,为充分利用吐鲁番现有光热资源,增加复播指数,提高单位土地面积的效益,在本所试验地进行了"两早配套"技术的对比试验,已初步确定吐鲁番区域可种植复播棉,为吐鲁番区域农业生产高效多元化发展开辟了一条新途径. 相似文献
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有关花生生长发育最佳温度范围已有不少研究报道。考克思1979年报道,在控制条件下,昼/夜温度30/26为营养生长的最佳温度;Fortanier、E. J. 1957年报道其营养生长的最佳温度为35/20和30/35;]acobs.W.P.1951年报道,最佳温度为26/30;K.Nakyama1974年报道,最佳温度为35/25;Wood.I.M.W.1968年报道,最佳温度为25/25℃。 相似文献
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洪河农场位于东北三江平原偏东部,年有效积温2350℃左右,无霜期125天左右,属寒冷稻作栽培区。80年代农场主要种植大豆、小麦。90年代以来,利用地下水资源开发种稻,目前已发展水稻133万ｈｍ2,占全种植面积的73%,总产占92%,取得了较好的经济效益,同时在寒冷低湿地井水种稻方面取得了一些经验,促进了水稻生产的发展。1 抢农时,争积温寒冷稻作区水稻栽培历来把有效利用积温作为增产的关键措施。旱育稀植秧田,在保护地栽培条件下,当外界气温稳定通过5℃时,塑料棚内温度可达12～15℃,此时即为水稻播种的始期。洪河农场气温稳定通过5℃的时间约为4… 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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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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《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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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
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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