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1.
不同浓度的钾处理对丝瓜幼苗抗寒性的影响 总被引：1，自引：0，他引：1
为探讨低温胁迫下不同浓度钾处理对丝瓜幼苗生理影响及其抗寒性的差异, 以 “翡翠二号” 丝瓜为试验材料, 在人工气候培养箱内采用基质培育丝瓜幼苗, 并分别用不同 K+浓度的营养液处理丝瓜幼苗, 研 究 低 温(夜晚 8 ℃, 白天 13 ℃)条件下其对丝瓜幼苗叶片相对电导率、 冷害指数、 叶绿素含量、 丙二醛含量、 可溶性糖含量、 脯氨酸含量等指标的影响。 结果表明： 随着 K+处理浓度增加, 壮苗指数先升后降, 处理浓度为 9.00 mmol/L壮苗指数显著高于对照; 随着低温处理时间的延长, 丝瓜幼苗的冷害指数上升、 叶绿素含量下降、 相对电导率上升、 MDA 含量增加、 可溶性糖和脯氨酸含量增加, 不同浓度 K+处理间差异显著性和变化幅度不同。 综合各项生理指标, 低温下 K+处理可显著降低丝瓜幼苗的冷害, 提高幼苗的抗寒性, 其适宜浓度为 9.00 mmol/L。 相似文献
2.
研究不同浓度的外源NO供体硝普钠（sodium nitroprusside, SNP）溶液对8 ℃低温胁迫下豇豆幼苗生长和生理特性的影响,结果表明,0.5~1.5 mmol/L外源NO处理下,豇豆幼苗叶面积、根冠比、壮苗指数有所提高,脯氨酸（Pro）、可溶性蛋白和叶绿素含量增加,丙二醛（MDA）含量降低。过高或过低浓度的外源NO对低温胁迫下豇豆幼苗生长的缓解作用均不显著,过低浓度的外源NO会促进MDA累积。在低温胁迫下,适当浓度的外源NO能促进脯氨酸和可溶性蛋白的形成,提高叶绿素含量,降低膜脂过氧化程度,从而增强豇豆幼苗对低温胁迫的适应性。 相似文献
3.
磷钾对小麦幼苗抗寒性的影响 总被引：4，自引：0，他引：4
为了探索低温胁迫下磷钾元素对小麦幼苗抗寒性的影响机理,对不同磷钾处理的小麦幼苗进行低温胁迫,测定和分析了相对电导度、可溶性糖含量、丙二醛含量、叶绿素含量、脯氨酸含量和SOD酶活性的变化.结果表明,低温胁迫下,磷素和钾素处理与对照相比明显降低了小麦幼苗组织的相对电导度和丙二醛含量,增加了可溶性糖和脯氨酸含量,提高了SOD酶活性;其中多数指标的磷钾配合处理效果更好.说明磷钾处理可以明显地增强低温下小麦幼苗的抗寒性,减缓低温对小麦幼苗的胁迫伤害,尤其是磷钾的配合施用对增强小麦幼苗的抗寒效果更好. 相似文献
4.
5.
钙对低温胁迫下木薯抗寒相关生理指标的影响 总被引：7，自引：0，他引：7
以华南8号木薯为试验材料,将生长一致的木薯幼苗用0、10、20、30、40、50 mmol/L等6个梯度的Ca2+进行处理后,对其进行4 ℃低温胁迫,测定抗寒相关生理指标。结果表明：在20 mmol/L外源Ca2+的作用下,木薯的各项抗寒生理指标较优,膜伤害率、膜脂过氧化产物MDA（丙二醛）含量降低,而保护酶SOD（超氧化物酶）和POD（过氧化物酶）、可溶性糖、可溶性蛋白、游离脯氨酸含量上升,幼苗抗寒性提升效果较明显。Ca2+浓度过高反而产生“毒害”作用,不利于其抗寒性增强。 相似文献
6.
香蕉是世界进出口贸易中具有重要经济价值的水果,也是非洲国家的粮食作物。盐害是影响香蕉产量和品质的重要因子之一。巴西蕉是我国华南地区的主栽品种。水杨酸在植物生理和代谢中扮演重要角色。盐胁迫下,外源水杨酸处理巴西蕉（Musa AAA Cavendish var. Brazil）幼苗的生理指标的变化未见报道。本研究通过叶面喷施0、0.5、1.0、2.0 mmol/L外源水杨酸,测定70 mmol/L NaCl胁迫下的巴西蕉幼苗叶片相对含水量、叶绿素含量、脯氨酸含量等生理指标的变化。结果表明,盐胁迫下巴西蕉幼苗的叶片相对含水量和叶绿素含量与对照相比显著下降,而脯氨酸含量、可溶性糖含量、可溶性蛋白含量以及丙二醛含量与对照相比均显著上升。施加0.5、1.0 mmol/L水杨酸处理与盐胁迫相比提高叶片相对含水量和叶绿素含量,提高叶片脯氨酸、可溶性糖和可溶性蛋白的含量,并且降低叶片丙二醛含量,而2.0 mmol/L 水杨酸处理的叶片相对含水量、脯氨酸含量、可溶性糖和可溶性蛋白含量与盐胁迫处理的差异不显著。因此,施加较低浓度的水杨酸（0.5、1.0 mmol/L）可在一定程度上缓解盐胁迫现象,但是高浓度水杨酸（2.0 mmol/L）缓解效果不明显,其中以1.0 mmol/L水杨酸处理效果最好。 相似文献
7.
通过室内砂培试验,研究低温逆境下氯化胆碱包衣玉米种子对其萌发及幼苗生理生化指标的影响。结果表明,低温逆境下氯化胆碱包衣能显著提高种子发芽率、发芽指数和活力指数,并提高种子发芽势;包衣处理明显提高低温逆境下玉米幼苗的苗高、根长、茎粗、根冠比和单株干重,具有良好的壮苗作用;低温逆境下包衣处理的幼苗叶片叶绿素含量和脯氨酸含量均高于对照,丙二醛含量和相对电导率低于对照。 相似文献
8.
低温胁迫下几种药剂对毛豆幼苗某些生理指标的影响 总被引：1，自引：1，他引：1
试验采用几种药剂对毛豆进行处理,测定其在低温胁迫下对毛豆幼苗某些生理指标及其抗寒性的影响,结果表明:采用几种药剂处理后,在低温胁迫下,与对照相比可增加根系活力、抑制丙二醛增生、降低细胞膜透性和提高叶绿素含量、脯氨酸含量、可溶性糖含量、细胞保护酶的活性等,增强了毛豆幼苗对低温逆境的抵抗能力,由试验所得众多生理指标进行综合分析可知,几种药剂以绿风95表现最好。 相似文献
9.
外源水杨酸对小麦幼苗镍毒害的缓解效应 总被引：3，自引：0，他引：3
为了解外源水杨酸(SA)对小麦镍胁迫的缓解作用,以小麦品种陇春3031为材料,采用溶液培养法,研究了不同浓度的SA对1 mmol·L-1 Ni2+胁迫下小麦幼苗生长及生理指标的影响。结果表明,1mmol·L-1 Ni2+胁迫显著降低了小麦幼苗的鲜重、干重、叶绿素含量、脯氨酸含量、过氧化物酶(POD)活性,显著提高了小麦幼苗丙二醛(MDA)含量。与单独Ni2+胁迫相比,0.1和0.5mmol·L-1 SA处理,可显著提高小麦幼苗地上部和根的鲜重和干重(P0.05),增加小麦幼苗叶绿素a、叶绿素b和总叶绿素含量,且叶绿素a/b显著升高。0.1mmol·L-1 SA处理,小麦幼苗总叶绿素含量升高了37.77%;提高了小麦幼苗叶和根中的POD活性和叶中的脯氨酸含量,降低了小麦幼苗根中脯氨酸含量;有效抑制了小麦叶和根中MDA含量的增加。说明适宜浓度的SA处理能缓解镍胁迫对小麦幼苗的毒害,增强其抗镍胁迫能力。 相似文献
10.
外源亚精胺对盐胁迫下黄瓜幼苗耐盐性的影响 总被引：1，自引：0，他引：1
为探讨盐胁迫下不同浓度外源亚精胺处理对黄瓜幼苗耐盐性的影响,以“津春四号”黄瓜为试验材料,在人工气候培养条件下,采用基质培育法研究了不同浓度(0、50、100、150、200、250 mg/L)外源亚精胺对200 mmol/L NaCl胁迫条件下的黄瓜幼苗各项形态指标和叶绿素含量、丙二醛含量、电解质渗透率、可溶性糖含量以及蔗糖含量等生理指标的影响.结果表明:盐胁迫下,经外源Spd预处理的黄瓜幼苗各项形态指标和叶绿素含量显著升高;100 mg/L的Spd处理可显著降低叶片丙二醛含量,最大降幅可达47.4％;100 mg/L Spd处理浓度可显著降低黄瓜幼苗相对电导率;较高浓度的Spd处理,可显著提高幼苗可溶性糖含量,而较低浓度的Spd处理,可提高幼苗蔗糖含量.综合各项生理指标,盐胁迫下Spd处理可显著缓解黄瓜幼苗的盐害,提高幼苗的抗盐性. 相似文献
11.
12.
《Journal of Crop Improvement》2013,27(2):81-114
Summary The efficiency of N fertilizers is usually poor; often less than 50% of the applied N is taken up by the crop. This review focuses on various N fertilizers with respect to the significance of different N loss pathways, namely (i) ammonia volatilization, (ii) dinitrogen and nitrogen oxide emissions, and (iii) nitrate leaching. Further, the significance of biological N immobilization, ammonium fixation and, finally, the impact of nitrate vs. ammonium uptake on crop yield are also discussed. The reviewed literature shows that N fertilizers may differ markedly in their susceptibility to losses. There is, however, considerable scope to improve N efficiency of each N source by proper N management practices. 相似文献
13.
Novel food and non-food uses for sorghum and millets 总被引：4，自引：3，他引：4
Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity. 相似文献
14.
Whereas the concept that availability of resources drives seed production is sound in principle, it is incomplete as there are many solutions to the allocation of resources that derive from the trade-off between number and size. This paper examines evolutionary aspects of this trade-off in annual grain crops. The analysis is centred on the working hypotheses that, for a given species and environment, allocation of resources to reproduction involves (H1) high plasticity in seed number, which allows for variable resource availability, and (H2) a relatively narrow range of seed size that results from evolutionary and agronomic selection. Comparisons between crops and fish are used to highlight common evolutionary elements in taxa where parents provide little or no care to their offspring, with the consequence that both number and early survival of offspring, hence fitness of parents, are partially related to embryo size and reserves.
The plasticity of seed number in relation to availability of resources is analysed against the established relationship between offspring number and parent growth rate during critical stages. The notion that seed size is under stabilising selection is analysed against three conditions: (1) mean seed size is conservative for a given species and environment, (2) seed size affects fitness, and (3) seed size is heritable. Databases from published papers were compiled to analyse the relative variability of seed size and number, and the heritability of seed size. Evidence for and against the link between seed size and parental fitness is revised using the Smith–Fretwell model as framework (Am. Nat., 108, 499–506).
The proposal of high plasticity of seed number and narrow variability of seed size resulting from stabilising natural selection is generally consistent with evolutionary and genetic considerations. Agronomic selection may have reinforced natural selection leading to relatively narrow seed size in species such as wheat and soybean, where cultivated types retained high plasticity for seed number. In contrast, selection for one or few inflorescences in crops like sunflower and maize may have morphologically reduced seed number plasticity and increased variability of seed size and its responsiveness to resource availability in relation to their wild ancestors. 相似文献
15.
Yanhua Lu Chongwei Zhang Peter Bucheli Dongzhi Wei 《Plant foods for human nutrition (Dordrecht, Netherlands)》2006,61(2):55-63
Flavonoids-enriched tissues of citrus such as peel, immature fruit and flower are consumed as culinary seasonings, tea ingredients in China for centuries. This HPLC quantitative study on the five citrus flavonoids, naringin, hesperidin, neohesperidin, sinensetin and nobiletin on a wide range of Chinese citrus fruits and several Traditional Chinese Medicinal food ingredients in East China, revealed a great diversity in flavonoid composition. Huyou peel (C. paradisi cv. Changshanhuyou) was found to be the best naringin (3.25%) and neohesperidin (2.76%) source; C. aurantium, a major ingredient of several citrus-related TCM, is also a suitable source of naringin and neohesperidin, and a good juice source for flavanone glycosides; the peel of Wenzhoumiju (C. unshiu) is one of the richest local species in hesperidin (up to 6.25%); Zaoju (C. subcompressa) has the highest content of nobiletin (0.59%), a polymethoxylated flavone. LC-ES-MS analysis of Zanthoxylum genus for flavonoids revealed for the first time the presence of significant amounts (0.74%) of hesperidin in the root of Liangmianzhen (Z. nitidum (Roxb.) DC), a relative of Sichuan pepper, which is a spice widely used in China. 相似文献
16.
Summary The viability of five pathogens was decreased by treatment with hot water when tested in vitro.Polyscytalum pustulans was most sensitive andRhizoctonia solani least sensitive.
Potato tubers were exposed to 55°C for 5 min in a commercial continuous hot water treatment plant using naturally contaminated
seed tubers and tubers which had been inoculated by dipping in comminuted cultures. The frequency of eyes colonised byP. pustulans, Helminthosporium solani, andR. solani was reduced to virtually zero and the effect persisted on tubers subsequently stored at 4°C and at 15°C for up to 16 wk.
Results withColletotrichum coccodes were inconclusive. Treatment suppressedPenicillium spp. which, however, rapidly recolonised the eyes during storage, leading to higher contamination levels in the treated than
in the untreated tubers. With tubers inoculated withPhoma foveata, good control was achieved when the incubation period before treatment was 10 d but not when the period was 42 d. 相似文献
17.
《Journal of Crop Improvement》2013,27(2):379-400
Summary Heterocyclic 1,4-benzoxazin-3-ones and related benzox-azolinones are important natural products of the cereal crops maize, wheat and rye. Much research has focused on the role of these compounds as defensive agents against plant diseases and pests. Studies of a wide variety of biological effects on herbivores and nematodes, plant pathogenic fungi and bacteria are reviewed in this article. Phytotoxic activity of the compounds is also considered with respect to allelopathic interaction with higher plants. Recent investigations of molecular aspects of interactions of cyclic hydroxamic acids and related benzoxazo-linones with acceptor organisms have demonstrated different effective detoxification strategies and tolerance mechanisms. This research has greatly advanced our knowledge about the multiple roles that these allelochemicals play in ecological systems. 相似文献
18.
Potential of dry fractionation of wheat bran for the development of food ingredients,part I: Influence of ultra-fine grinding 总被引：1，自引：0，他引：1
Youna Hemery Marc Chaurand Ulla Holopainen Anna-Maija Lampi Pekka Lehtinen Vieno Piironen Abdelkrim Sadoudi Xavier Rouau 《Journal of Cereal Science》2011
Wheat bran is an undervalued by-product of white flour and has great nutritional potential due to its high content in fibres and bioactive compounds. Micronized bran could be used as a food ingredient to improve the nutritional potential of cereal products, or be used as a starting material for other processes (bioactive compound extraction or bran fractionation). The aim of this work was to find a way to efficiently decrease the particle size of bran. The influence of the grinding temperature (ambient or cryogenic grinding) on the granulometric distribution of particles, their composition, and their microstructure was studied, at lab-scale and pilot-scale. It showed that the intrinsic characteristics of bran (glass transition within intermediate layers at −46 °C) had more influence on its grinding behaviour than the type of grinding device used: the particles size distributions obtained after grinding at lab-scale and pilot-scale were very similar. At both scales, the granulometric curves were narrow for cryogenic grinding, while for ambient grinding they were spread over the whole particle size range. Ultrafine particles were obtained in both ambient and cryogenic conditions. Negative temperatures, by increasing the material’s brittleness, favoured a fast fragmentation of bran: one step of cryogenic grinding allowed a median particle size of nearly 50 μm to be reached, whereas three successive steps of ambient grinding were needed for the same result. On the other hand, ambient temperature favoured the dissociation of the different constituent layers of wheat bran, and produced less composite particles than cryogenic grinding. 相似文献
19.
Multiple use of plants: Studies on selenium incorporation in some agricultural species for the production of organic selenium compounds 总被引：3，自引：0，他引：3
The technique of spraying plants with inorganic forms of selenium can be employed for phytochemical production of organic selenium compounds. Fractionation of the plant material makes it possible to produce a highly concentrated and well defined selenium supplement with potential use in animal and human nutrition. The fractionation also gives opportunities to combine production of organic selenium compounds with other products, for example plant fibres. Multiple use of plants can contribute to a more efficient utilization of land area (in comparison to monocultures solely adapted to food production). It also gives the opportunity to develop systems suitable for long term fixation of carbon, as long as the plant material is not reoxidised to carbon dioxide. Plant fibres could provide raw material for the production of paper or building materials in combination with the production of organic selenium compounds preferentially accumulated in another fraction of the processed plant. 相似文献
20.
Summary
Macrosiphum euphorbiae, collected in the field from potato plants infected with potato leafroll virus (PLRV), transmitted the virus to fewer potato
plants in a field trial than did laboratory-rearedMyzus persicae. In the laboratory,M. persicae was the only efficient vector of PLRV fromPhysalis floridana seedlings, potato sprouts or excised leaves toP. floridana. Two clones ofM. euphorbiae and one clone ofAulacorthum solani transmitted PLRV from infected potato plants toNicotiana clevelandii as effeciently asM. persicae but a clone ofAphis gossypii was an inefficient PLRV vector. An isolate of PLRV, whichM. persicae transmitted inefficiently from potato toN. clevelandii, was also transmitted inefficiently byM. euphorbiae andA. solani. 相似文献