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苎麻主要品质性状研究进展 总被引:2,自引:0,他引:2
苎麻纤维的细度、强力、断裂强度、均匀度、结晶度是衡量苎麻纤维品质优劣的几项主要指标。本文就苎麻主要品质性状的研究方法、进展及遗传改良进行概述,并对目前研究中存在的问题进行了讨论。 相似文献
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我场历年苎麻种植面积上千亩,近年已逐步扩大到5000多亩。由于苎麻系多年生宿根性草本植物,杂草种类繁多,为害时间长。若不及时防除,土壤肥力大量消耗,造成苎麻减产,同时引起苎麻败蔸,缩短宿根年限。为此,我们于1977年、1980-1985年对苎麻地杂草进行了调查研究和化学防除试验,现将调查和试验结果报道如下。 相似文献
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苎麻属野生植物农艺性状、纤维物理性能及其相关性研究 总被引:1,自引:0,他引:1
对苎麻属野生植物农艺性状、纤维物理性能及其二者相关性进行研究,结果表明:苎麻属植物各农艺性状值表现均不及栽培苎麻,尤以茎粗、鲜皮厚度、鲜皮重和原麻重表现较甚,分别较对照减幅为42.37%~77.97%、20.00 %~70.00%、54.92% ~98.77%和67.90%~98.83%;野生植物中密球苎麻、水苎麻和疏毛水苎麻的纤维细度较高,分别较栽培苎麻高出27.89%、23.81%和6.73%,表明野生苎麻中存在高细度优良基因;纤维细度除与原麻长度呈较小正相关性外,与其它农艺性状指标达不同程度负相关;说明苎麻属野生种质在提高栽培苎麻产量上应用价值不大,但在提供选育优良纤维基因,改善纤维品质上具有重要应用价值. 相似文献
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分析自动量热仪测定煤发热量的不确定度,找出影响煤发热量测定的主要因素,为评价检测报告的可靠程度提供科学依据。本研究以自动量热计法测定煤的发热量试验为例,根据《测量不确定度评定与表示》(JJF 1059-1999)有关规定分析不确定度的来源,评定自动量热仪测定煤发热量的不确定度。 相似文献
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The objective of this special issue is to highlight the current state of research in the field of insects as food and feed, but also other aspects on the exploitation of insect farming. In this editorial, we make a short introduction of the topic of the special issue, briefly present the contributions that are collected in it and offer some thoughts on the future research priorities and challenges that should be addressed. Regarding insect farming, there are additional applications, such as fertilizer, health-promoting products, and cosmetics, that can be produced and utilized, that go far beyond food and feed production. 相似文献
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Potato tuber tissue inoculated at cutting withFusarium spp. orErwinia carotovora and exposed to conditions favorable for infection did not heal rapidly enough to prevent decay. Seven days of wound healing at 20 C and high relative humidity prior to inoculation were necessary to provide protection againstFusarium and two days were required to protect againstErwinia. Histological examination of cut and chemically treated tuber tissue revealed that the wound healing process was only minimally affected by mancozeb, zineb-streptomycin, zineb-fir bark, captan, captan-mertect, captan-fir bark, and sodium hypochlorite. Ethylmercury p-toluene-sulfonanalide and pyrrolidine induced formation of discontinuous wound periderm after 21 days of healing. Streptomycin and captan-rhodamine had very detrimental effects on wound healing and suberin formation. In general, the seed-piece treatment chemicals tested had only minor effects on normal wound healing. It is concluded that wound healing alone may not be sufficient to controlFusarium caused seed piece decay and chemical treatment is recommended to provide protection until wound healing can occur. At least two days of wound healing are required for control of decay caused byErwinia carotovora. 相似文献
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小麦高温抗条锈性表达与苯丙氨酸解氨酶和多酚氧化酶活性的关系 总被引:7,自引:2,他引:7
测定了小麦高温抗条锈性表达过程中小麦叶内苯丙氨酸解氨酶和多酚氧化酶的活性变化。结果表明,高温抗条锈性品种,在小麦高温抗条锈性表达过程中,接种寄主叶内PAL活性对高温非常敏感。在高温处理12h时PAL活性就很快增高,到24h就达到活性高峰,形成一个对高温敏感的特异峰,且该峰可以从高温处理12h持续到72h。小种专化抗锈性的PAL活性也较对照增高,但对温度处理没有明显的活性峰。多酚氧化酶在高温抗条锈性表达过程中变化与对照无明显变化。 相似文献
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温度对不同花生品种种子活力的影响 总被引:3,自引:0,他引:3
分析研究了温度条件对不同花生品种种子活力的影响,以便掌握花生播种前最佳的预处理温度。试验通过生物化学、光谱分析和生理学综合进行。研究表明,在不同温度条件下,温度对不同花生品种的发芽率、发芽势、发芽指数影响极显著。在低于最适温度时,种子活力随预处理温度的升高而增强;在温度超过最适温度时,种子活力随温度升高逐渐降低直至丧失活力。六个品种分别通过响应曲面法拟合获得的最佳预处理温度为38.11℃、44.05℃、43.37℃、47.18℃、40.23℃和44.41℃。 相似文献
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以温敏核不育水稻培矮64S为材料,采用10~15 cm水层灌溉处理和无水层对照,对植株温度及其与植株冠层小气候和灌溉水因子的关系作了分析。水稻植株温度与150 cm大气温度在数值和相位上均存在一定差异。8:00~20:00植株温度均明显低于大气温度,21:00~次日7:00植株温度与大气温度基本相同;日最高植株温度出现在13:00,比最高大气温度提前1 h,但日最低植株温度和最低大气温度均出现在6:00;植株温度的平均日较差比气温小。在同一高度上相比,晴天6:00~13:00植株温度比空气温度高,而且提前1 h升温,18:00~次日6:00则两者逐渐趋同或植株温度稍低;而在阴天,植株温度则全天一直高于空气温度,最高温度出现的时间也相同。植株温度白天的变化主要受太阳辐射的影响,天空状况(云量或日照时数)和风速都通过对辐射强度的调节和热量的交换而产生作用。植株温度夜间的变化主要受灌溉水的影响。在本试验条件下,日平均气温(Ta)29.6℃是灌溉水提高或降低植株温度的临界温度值,当Ta>29.6℃时,灌溉水具有降低植株温度的作用,反之,灌溉水具有提高植株温度的作用。植株温度与水 气温差符合二次曲线关系。植株冠层在白天吸收或反射太阳辐射,夜间则阻挡热量散失,对调节植株温度具有明显的缓冲效应。通过相关分析和回归拟合,建立了两个可供实用的水稻植株温度的环境模型。 相似文献
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秋季低温对水稻空瘪率的影响和有关指标值的研究 总被引:3,自引:0,他引:3
本试验旨在探索秋季低温对水稻开花结实影响的若干不够明确的问题。结果表明:低温指标中,日平均温度是主要指标;日最低温度是减数分裂期的辅助指标;日最高温度是开花期的辅助指标。如在不同低温敏感期均受害较重,则低温危害表现为累加效应。计算低温临界温度时,籼粳稻均以连续三天的温度平均为好。提出了开花期籼稻、籼型杂交稻、中粳、晚粳四类型的低温临界值。开花期的日温差过大或过小均导致空瘪率上升。气象因子中,温度对空瘪率的影响最大;适温条件下,空瘪率与日照呈负相关:雨量与空瘪率关系不显著。 相似文献
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《Field Crops Research》1987,16(1):33-42
Predictions of the date of harvest of vining peas (Pisum sativum L.) were performed by means of statistical models. Simple models based on sowing-to-harvest prediction criteria and two-component models based on a combination of sowing-to-emergence and emergence-to-harvest prediction criteria were applied. The criteria used were number of days, and soil and air temperature sums, with base temperature in the range 2.6–3.8°C and 3.0–6.0°C, respectively.The best predictions of the harvest date were obtained with two-component models, and sowing-to-emergence predictions criteria based on soil temperature were better than others examined. Among two-component models, the smallest error of prediction-2.4 days-was obtained with the model using sowing-to-emergence soil temperature sums with base temperature 3.0°C, and emergence-to-harvest number of days as prediction criteria. The prediction model traditionally used in practice applies sowing-to-harvest air temperature sums with base temperature 4.5°C as prediction criterion, and the error of prediction of this model was 4.3 days.Close linear relationships were found between number of nodes and air temperature sums accumulated from sowing or emergence. In consequence, the number of nodes is a reliable indicator of the actual air temperature sum status of the crop.Some practical aspects of applying two-component models and node counting for predicting the date of harvest of vining peas are discussed. 相似文献