棉花优质铃开花期的模拟与播前决策选择

一、棉花优质铃开花期研究棉花成铃的空间分布表明,铃重的分布以果节而言,由内而外地递减,棉铃的纤维品质也有同样规律,所以将棉铃内围1,2果节称为优质铃空间部位;以果枝层而言,中部果枝上的铃较大,其次是下部果     

不同类型土壤棉花产量构成因素及棉铃空间分布研究

研究了膜下滴灌不同类型土壤棉花产量构成因素及棉铃空间分布规律。结果表明：产量构成各因素与皮棉产量之间均为正相关关系,且子棉与皮棉、铃数,皮棉与衣分、子数、地上干重、铃重,子数与地上干重的相关系数达极显著水平。壤土结铃能力最强,其次为粘土,单株成铃最少的是沙土地。从棉花不同果枝结铃的空间分布看,中部果枝结铃数高于棉株下部和上部,其中以壤土最高。不同类型土壤的棉田应进一步提高棉铃中部果枝成铃率,以提高棉花的品质;并进一步挖掘上部铃和外围铃的潜力,以提高棉花的产量。沙土地,应充分提高棉株的上部成铃率。     

不要盲目采摘老铃

近两年来,伴随棉花产量的提高,原棉品级和品质有明显下降。咎其原因,与近两年大力提倡的采摘老铃有关。这批棉铃的铃龄五十天,壳黄嘴开裂。实验证明,半开棉铃的纤维强力为2.7～2.9克,而全开棉铃的纤维强力则为3.8～4.0克。。由此可见,强行采摘的老铃,棉花并未真正成熟,不仅纤维成     

棉花蕾铃时空分布的计算机模拟

一、问题的提出大量田间试验表明:棉花的铃重、衣分、每铃种子数、每粒种子纤维重以及纤维品质都与棉铃的空间分布和开花成铃时间密切相关。随着气温以及水肥条件的变化,棉花果枝、果节的出生速率不同,由蕾到花,由花     

棉花花铃期管理浅议

棉花花铃期是形成产量的关键时期,由营养生长和生殖生长并进逐渐转向以生殖生长为主,是这一时期棉花生育的主要特点。因此,协调营养生长和生殖生长的矛盾,防止早发棉田早衰,促使迟发棉田早熟,力争在当地最佳生态条件下,使不同生长型的棉花着结较多的优质棉铃,是该阶段田间管理的重心。可见,花铃期管理的成败,对棉花产量的高低和纤维品质的优劣影响极大。现就花铃期管理,择要概述如下。     

棉花花铃期田间管理技术

棉花花铃期是指从开花到棉铃期田间管理铃成熟开始吐絮的一段时间,其间棉田管理的好坏,临川区农业局,对产量的高低和品质的优劣都起着决定性的作用。因此,花铃期的田间管理十分重要。1灌水抗旱。本地7-8月份常常出现伏旱或秋旱,有时伏旱连秋旱,此期间又是棉花一生中需水最多的时期,若棉田供水不足,就会使蕾铃大量脱落、纤维变短、成熟度差,导致降质减产。因此,棉花花铃期遇上干旱必须及时灌水,灌水时要做到三看:一看苗。当棉苗红茎比迅速上升,顶端绿色部分缩短到10cm以下,叶色暗绿无光,顶部3～4片叶中午前后萎蔫下垂,应灌水。二看地。一般取…     

氮素胁迫下棉株结铃、棉铃发育和纤维品质的分析

进行了两年的温室试验以明确氮素对棉花结铃、棉铃发育和纤维品质的影响。棉株结铃和棉铃成熟期的叶片含氮量变幅为最低施氮处理的1％至最高施氮处理的3％。氮素胁迫降低了棉株叶面积、铃数和单铃重,且单株铃数的下降程度大于铃重。氮素对棉铃成熟期没有影响。氮素胁迫下,棉铃在主茎和果枝上所处的节位影响到单铃纤维重。但是,氮素胁迫只影响纤维品质性状中的纤维齐整度。第二果节棉铃的纤维麦克隆、长度、强度和整齐度值均低于第一果节的,但纤维伸长率较高。     

棉花稀植大棵群体不同果枝产量与品质分布特征的研究

以湘农杂棉68为试验材料,研究其在稀植大棵栽培下棉花不同果枝产量与品质的空间分布特征.结果表明：不同果枝棉铃的产量和纤维品质性状存在差异.第6～17果枝是构成棉花产量的重要组成部分,其成铃数多、单铃重高、衣分波动较大;中下段第7～10果枝和顶端第20、22果枝的纤维品质具有优势,其纤维长度、比强度较好.棉铃产量和品质综合性状空间分布的聚类分析表明,果枝可分成差异明显的四大类,按优劣性状表现为中上部＞中下部＞顶部＞基部.     

高温对棉花生殖器官和纤维发育的影响及应对措施

正7-8月正值棉花开花结铃期,是形成产量的关键时期,也是增蕾促花保铃、提升棉纤维品质的敏感阶段。近年来,新疆阿克苏地区持续高温天气过程多发频发,对棉花产量和品质带来不利影响。此外,高温还造成棉花品质的下降。现就高温对棉花蕾花铃和棉纤维发育的影响进行分析,提出应对高温的技术措施,以期指导棉花生产,力争把气温对棉花产量和品质的影响降至最低。1阿克苏持续性高温天气过程多发、频发     

高温对棉花花器官发育和棉铃生长的影响

棉花的生长发育与温度有密切的关系。如在适宜的温度范围内温度偏高,则有利于棉花正常生长,并能获得较高的产量和较好的纤维品质。但是若遇到高温,不仅会影响到棉花的正常生理活动,甚至会导致幼铃脱落。本文着重研究在33℃以上的高温对棉花花器官的发育和棉铃生长的影响。     

Preparation and characterization of fibers of waste and fresh polyethylene terephtalate and mixtures of them

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.     

我国麻类标准现状与分析

介绍了我国麻类标准的现状。通过分析,指出了存在的问题,主要表现在标准体系不完善、标准更新不及时,协调性差及贯彻执行不力等。提出了我国麻类标准应采取的对策。     

Characteristics of photosynthesis and conductance of potato canopies and the effects of cultivars and transient drought

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.     

Effects of Organic and Chemical Fertilizers and Arbuscular Mycorrhizal Inoculation on Growth and Quality of Cucumber and Lettuce

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.     

水稻病虫害绿色防控与统防统治融合技术模式示范

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。     

热区蔬菜质量安全分析与评价

对影响我国热区主要蔬菜产前、产中、产后的质量安全相关因素与现状进行调研,获取基础数据与有关信息。对比分析国内不同生产区质量安全存在的差异与差距,研究我国热区蔬菜从生产至市场各个环节的质量安全评价方法,提出建立我国热区蔬菜质量安全评价体系方案。     

棉花病虫全程绿色防控技术应用与推广

经过多年实践,探索总结出抗病虫品种、频振式太阳能杀虫灯、糖盆诱蛾、黄蓝板诱虫、生物多样性控虫等绿色防控技术,形成了切合库尔勒实际的棉花病虫全程绿色防控技术模式。介绍了上述技术措施及其在当地棉田的推广应用效果。     

生物质能作物——甘薯开发利用现状及趋势

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”。     

春季氮肥和多效唑调控对小麦生育和产量的影响

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。     

施镁量和施镁方法对烤烟生长发育和烟叶产量的影响

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。