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1.
追氮时期对冬小麦胚乳发育及灌浆特性的影响 总被引：1，自引：0，他引：1
为明确氮肥追施时期对冬小麦籽粒发育和灌浆特征的影响,选用冬小麦品种石麦18,采用随机区组设计,研究了LA1(春2叶期)、LA2(春3叶期)、LA3(春4叶期)、LA4(春5叶期)、LA5(春6叶期)5个追氮处理对籽粒胚乳细胞分裂增殖和灌浆特征的影响。结果表明,追氮时期对胚乳细胞增殖和灌浆特征均有显著影响。LA1、LA2和LA3处理的胚乳细胞在籽粒建成期分裂速率较高,而后分裂速率急剧下降,胚乳细胞数较少;灌浆速率表现为前期较高,后期较低;成熟时粒重较低。LA4处理能延长籽粒胚乳细胞增殖活跃期,在花后21 d后胚乳细胞仍然具有较高的分裂增殖能力,胚乳细胞数目最多,籽粒的最大灌浆速率最高,后期的灌浆能力较强,粒重最高。LA5处理胚乳细胞数较多,后期灌浆速率较低,粒重仅低于LA4处理。 相似文献
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通过Ｒｉｃｈａｒｄｓ方程模拟,探讨了双增剂地籽粒胚乳细胞增殖及粒重变化的影响。结果表明,双增剂通过提高胚乳细胞平均增殖速率来提高最终胚乳细胞数;通过提高籽粒平均灌浆速率和延长粒重活跃增长期来提高最终粒重,并且双增剂对粒重的效应表现为低肥处理大于高肥处理。 相似文献
4.
喷施6BA和ABA对冬小麦籽粒胚乳细胞增殖和淀粉积累的影响 总被引：1，自引：0，他引：1
为给植物生长调节剂的合理使用提供依据,在田间试验条件下,以小麦品种济南17和鲁麦21为试验材料,在小麦抽穗期喷施6-苄基腺嘌呤(6BA),开花期喷施脱落酸(ABA),研究其对小麦胚乳细胞增殖动态及淀粉积累、组分的影响.结果表明,喷施6BA能显著提高小麦籽粒的胚乳细胞数、胚乳细胞分裂中后期的增殖速率、粒重和淀粉积累量,且可降低小麦强势籽粒淀粉直/支比例,有利于淀粉品质的改善;但对弱势籽粒中的淀粉直/支比例没有显著的影响.喷施ABA能降低胚乳细胞分裂中后期的增殖速率,显著减少强势籽粒的胚乳细胞数,但对弱势籽粒的胚乳细胞数和粒重没有显著影响,对淀粉直/支比例的影响也不明显.2种外源激素处理都没有改变小麦籽粒的穗粒数和总淀粉含量,表明小麦粒重的变化可能主要是由胚乳细胞的增殖造成的. 相似文献
5.
黄淮麦区水、旱生态型小麦籽粒灌浆进程研究 总被引：5，自引：1，他引：4
为了解黄淮麦区水、旱两大生态型小麦品种的灌浆特性,选用目前该麦区推广的12个水地品种和6个旱地品种为材料,用Logisitic方程对其籽粒灌浆进程进行拟合,分析灌浆参数的变异及其与粒重的关系.结果表明,黄淮麦区的水、旱两大生态类型小麦在灌浆参数方面有着很大的不同.水地品种的平均灌浆时间比旱地品种长2.2 d,不同阶段的灌浆时间也相对较长,但不同阶段的灌浆速率均小于旱地品种.旱地品种的千粒重比水地品种高出2.07 g,而两大类型品种粒重受灌浆速率的影响大于灌浆时间的影响.在灌浆参数中,R(平均灌浆速率)、R_3(缓增期灌浆速率)、R_(max)(最大灌浆速率) 、T_(max)(达到最大灌浆速率的时间)与水地品种粒重显著相关,而R、R_2(快增期灌浆速率)、T_2(快增期时间)与旱地品种粒重显著相关.因此,平均灌浆速率、缓增期籽粒灌浆速率、最大灌浆速率及其出现的时间可作为水地小麦高产育种的重要选择指标.旱地育种者在注重平均灌浆速率的同时增加快增期的灌浆速率和时间,可保证籽粒干物质迅速积累,从而躲过后期干旱、干热风等危害,保证小麦粒重稳定提高. 相似文献
6.
氮肥用量对不同品质类型小麦品种籽粒灌浆特征和产量的影响 总被引：19，自引：0，他引：19
在大田条件下,以强筋小麦品种郑麦9023和豫麦34、中筋小麦品种豫麦18以及弱筋小麦品种豫麦50为试验材料,采用10、15和20 kg/667m2三种施氮水平,研究了氮肥用量对不同品质类型小麦品种籽粒灌浆和产量的影响。结果表明,在各施氮处理中不同品质类型小麦品种籽粒灌浆过程均呈“S”型变化,但模型参数因氮肥用量而不同。郑麦9023和豫麦18的各项灌浆参数均表现为15 kg/667m2>20 kg/667m2>10kg/667m2;豫麦34籽粒灌浆持续期、理论最大粒重、最大灌浆出现时间、有效灌浆持续期、有效灌浆持续期增加值、有效灌浆持续期灌浆速率均表现为15 kg/667m2>20 kg/667m2>10 kg/667m2,平均灌浆速率和最大灌浆速率表现为20 kg/667m2最大,15 kg/667m2次之,10 kg/667m2最小。豫麦50籽粒灌浆持续期、有效灌浆持续期以20 kg/667m2最长,15 kg/667m2次之,10 kg/667m2最小;最大籽粒灌浆出现时间、最大灌浆速率、有效灌浆持续粒重增加值、有效灌浆持续期灌浆速率以15 kg/667m2最高(早),20 kg/667m2次之,10 kg/667m2最低(晚);而理论最大粒重、平均灌浆速率则表现为10 kg/667m2>15 kg/667m2>20 kg/667m2。同时,郑麦9023、豫麦18和豫麦34粒重与各灌浆参数均呈正相关,郑麦9023粒重与籽粒灌浆持续期、平均灌浆速率和最大灌浆速率相关系数达到显著水平,与有效灌浆持续期相关系数达到极显著水平;豫麦18粒重与最大灌浆速率和有效灌浆持续期相关系数达到极显著水平,与平均灌浆速率之间达显著水平;豫麦34粒重与籽粒灌浆持续期相关系数达到显著水平;豫麦50粒重与籽粒灌浆持续期呈负相关,与平均灌浆速率、最大灌浆速率、有效灌浆持续期和有效灌浆持续期灌浆速率均呈正相关,差异均不显著。豫麦18和豫麦34在15 kg/667m2下产量最高,且差异分别达到极显著和显著水平,郑麦9023和豫麦50在20 kg/667m2下产量最高,差异达显著水平。 相似文献
7.
为了了解小麦在不利气候条件下的灌装机理，改善湖北小麦的产量与品质状况，作者以三种粒型小麦品种(系)为材料，研究了籽粒胚乳细胞增殖动态及其与体积和粒重的关系。结果表明，用Richards方程能较好地模拟胚乳细胞增殖动态。不同品种间胚乳细胞数有明显的差异，表现为大粒饱满品种(鄂恩1号)＞大粒不饱满品系(95A—10)＞小粒饱满品种(华走8号)。强势粒胚乳细胞分裂起始势高，达到最高增殖速率时间短，活跃分裂期长，可分裂出更多的胚乳细胞。弱势粒胚乳细胞增殖起始势低，细胞分裂速率变化缓慢，其最终胚乳细胞数显著低于强势粒。多元统计分析表明，决定籽粒体积大小的主要是胚乳细胞数和单个胚乳细胞大小，决定粒重大小的主要是胚乳细胞数和单个细胞重。 相似文献
8.
花后持续弱光对冬小麦光合特性及产量的影响 总被引：2，自引：0，他引：2
为给弱光条件下小麦持续高产及耐荫性筛选提供一定的理论依据,在大田条件下,以济麦22和济核916为试验材料,于花后设置3个不同的遮光处理(不遮光、遮光30%和遮光60%),分析花后持续弱光对小麦光合特性和产量的影响。结果表明,济麦22和济核916旗叶叶绿素a、b含量在花后0~25d保持较高水平,之后迅速降低。遮光后两品种旗叶的净光合速率下降,济麦22的干物质积累量和花前贮存干物质在花后向籽粒的转运量及两品种的经济系数显著降低。花后遮光改变了小麦籽粒灌浆进程,显著降低了两品种的平均灌浆速率和最大灌浆速率,延长了济麦22的渐增期和快增期持续时间,减少了缓增期的持续天数,遮光60%处理显著降低了济核916渐增期持续时间,推迟了其灌浆高峰的来临时间。遮光30%和60%条件下济麦22分别减产27.7%和35.4%,济核916分别减产29.49%和64.39%。遮光后冬小麦的穗粒数和千粒重随遮光强度的增加而降低。说明花后弱光会降低小麦光合能力,不利于植株干物质积累和籽粒灌浆,最终导致减产。 相似文献
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为了明确大粒小麦的灌浆特性,以豫农9901/周麦16重组自交系群体中籽粒大小基本一致而饱满度和粒重具有较大差异的11个半冬性品系为试验材料,以周麦18为对照,分析了籽粒灌浆特性及阶段性灌浆参数与粒重的关系.结果表明,籽粒灌浆呈“慢-快-慢”的变化规律,可以用logistic曲线方程拟合其增长趋势;粒重较高的品系W02、W03与对照周麦18具有相似的灌浆特性,其他品系的籽粒灌浆特性与对照周麦18有明显差异,表现在前期灌浆速率高于周麦18且增速较快,后期则明显低于周麦18且下降的幅度较大;在三个灌浆阶段参数中,缓增期灌浆速率、渐增期和快增期持续时间明显低于周麦18,而缓增期持续时间明显长于周麦18.通径分析表明,阶段灌装参数中对粒重直接作用最大的是快增期持续时间,其次是缓增期持续时间,但是缓增期持续时间对粒重的直接正向效应被其较大的负向间接效应所掩盖;快增期和缓增期灌浆速率对粒重的间接效应明显大于直接效应. 相似文献
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不同类型专用小麦品种胚乳发育的比较研究 总被引：1，自引：0，他引：1
为揭示不同类型专用小麦品种胚乳发育的差异,以强筋小麦皖麦38和弱筋小麦扬麦9号为材料,比较了两者胚乳细胞游离核分裂状况、细胞数目的增殖变化、细胞体积的变化、糊粉层发育、淀粉体和蛋白质体发育等内容,主要结果如下：（1）皖麦38游离核有丝分裂所占比例较大,扬麦9号无丝分裂所占比例较大,且受温度影响较大;（2）胚乳细胞增殖均呈"S"型曲线变化,皖麦38胚乳细胞增殖较快,胚乳体积较大,最终粒重较高;（3）皖麦38胚乳细胞中大淀粉体数目多于扬麦9号,而小淀粉体数目表现却相反;（4）皖麦38与扬麦9号相比较,糊粉层出现时间较晚,而且糊粉层细胞壁较厚,被甲苯胺蓝染色更浓;（5）成熟籽粒中淀粉粒形状有饼形、椭圆形和近圆球形三种。皖麦38胚乳中饼形和椭圆形淀粉粒较多,且相互结合较紧密;扬麦9号饼形和近球形淀粉粒较多,胚乳结构疏松。 相似文献
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《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.
Lakshman Lal 《Potato Research》1987,30(2):329-334
Summary The effects of the leaves of five plant species, one from each of the generaAmbrosia, Anemone, Eupatorium, Eucalyptus andLantana, on potato tuber moth were investigated under indigenous storage conditions at the Central Potato Research Station, Shillong
(1800 m above sea level). Their action was compared with that of a biological insecticide (spores ofBacillus thuringiensis), a chemical insecticide (carbaryl), and an untreated control. The data collected after six months storage on tuber damage,
sprout damage and the rotting indicated that the leaves ofLantana aculeata provided most protection to the tubers, reducing damage from over 70% in the check to below 5%, and sprout damage from over
45% to below 3%. Next best wasEucalyptus globulus followed byB. thuringiensis. They may be used on tubers stored for table use or for seed as they had no adverse effect on germination or on the yield
of a subsequent crop. 相似文献
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Joseph E. Laferriere Charles W. Weber Edwin A. Kohlhepp 《Plant foods for human nutrition (Dordrecht, Netherlands)》1991,41(3):277-282
Teas of plant origin traditionally consumed by the Mountain Pima of Chihuahua, Mexico, were analyzed for mineral nutritional content. Fe, Cu, Zn, Ca, and Mg composition was determined for native teas made from shoots ofTagetes lucida, T. filifolia, Elytraria imbricata, andHolodiscus dumosus, and from root xylem ofCeanothus depressus andPhaseolus ritensis. Native uses of these teas are also described. 相似文献
16.
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
17.
M. I. Siri P. Villanueva M. J. Pianzzola L. Franco Fraguas G. Galván M. Acosta F. Ferreira 《Potato Research》2004,47(3-4):127-138
Summary The in vitro antimicrobial activity of extracts from accessions ofSolanum commersonii Dun. collected in the south of Uruguay was investigated against five microorganisms including the pathogenRalstonia solanacearum. A total of 30 extracts corresponding to organic and aqueous extracts were studied. Interestingly, most of the positive results
for growth inhibition were againstR. solanacearum. The extracts were also analyzed for the presence of glycoalkaloids and lectins. Six of the ten aqueous extracts showed lectin
presence and a wide variation in the type and amounts of glycoalkaloids, was found. Results indicate that there is no clear
relationship between the antimicrobial activity against the five microorganisms screened and the presence or amounts of lectins
and glycoalkaloids, traditionally regarded as possible antimicrobial metabolites in theSolanum genus, which indicates the presence of as yet unidentified antimicrobial compounds. 相似文献
18.
Alejandro Carlos Tozzini María Fernanda Ceriani María Verónica Saladrigas H. Esteban Hopp 《Potato Research》1991,34(3):317-324
Summary Clones derived from thirty-one different accessions (nineteen of Argentine origin) belonging to eightSolanum species were screened for resistance to infection by potato virus X strain cp (PVX cp) by mechanical inoculation of plantlets
that had been micropropagated in vitro. Estimates of PVX multiplication obtained by enzyme linked immunosorbent assay and
slot blot nucleic acid hybridization allowed the identification of resistant clones derived from five accessions belonging
toS. commersonii S. oplocense, S. sparsipilum andS. tuberosum andigena. Resistant genotypes supported PVX concentrations 5 to 15 times smaller than did the susceptible control cultivar Spunta.
Graft inoculation test confirmed the presence of extreme resistance similar to that conferred by the ‘immunity’ gene X1 (also called RXact). 相似文献
19.
Rita Favas Janaína Morone Rosrio Martins Vitor Vasconcelos Graciliana Lopes 《Marine drugs》2022,20(3)
The loss of density and elasticity, the appearance of wrinkles and hyperpigmentation are among the first noticeable signs of skin aging. Beyond UV radiation and oxidative stress, matrix metalloproteinases (MMPs) assume a preponderant role in the process, since their deregulation results in the degradation of most extracellular matrix components. In this survey, four cyanobacteria strains were explored for their capacity to produce secondary metabolites with biotechnological potential for use in anti-aging formulations. Leptolyngbya boryana LEGE 15486 and Cephalothrix lacustris LEGE 15493 from freshwater ecosystems, and Leptolyngbya cf. ectocarpi LEGE 11479 and Nodosilinea nodulosa LEGE 06104 from marine habitats were sequentially extracted with acetone and water, and extracts were analyzed for their toxicity in cell lines with key roles in the skin context (HaCAT, 3T3L1, and hCMEC). The non-toxic extracts were chemically characterized in terms of proteins, carotenoids, phenols, and chlorophyll a, and their anti-aging potential was explored through their ability to scavenge the physiological free radical superoxide anion radical (O2•−), to reduce the activity of the MMPs elastase and hyaluronidase, to inhibit tyrosinase and thus avoid melanin production, and to block UV-B radiation (sun protection factor, SPF). Leptolyngbya species stood out for anti-aging purposes: L. boryana LEGE 15486 presented a remarkable SPF of 19 (at 200 µg/mL), being among the best species regarding O2•− scavenging, (IC50 = 99.50 µg/mL) and also being able to inhibit tyrosinase (IC25 = 784 µg/mL), proving to be promising against UV-induced skin-aging; L. ectocarpi LEGE 11479 was more efficient in inhibiting MMPs (hyaluronidase, IC50 = 863 µg/mL; elastase, IC50 = 391 µg/mL), thus being the choice to retard dermal density loss. Principal component analysis (PCA) of the data allowed the grouping of extracts into three groups, according to their chemical composition; the correlation of carotenoids and chlorophyll a with MMPs activity (p < 0.01), O2•− scavenging with phenolic compounds (p < 0.01), and phycocyanin and allophycocyanin with SPF, pointing to these compounds in particular as responsible for UV-B blockage. This original survey explores, for the first time, the biotechnological potential of these cyanobacteria strains in the field of skin aging, demonstrating the promising, innovative, and multifactorial nature of these microorganisms. 相似文献
20.
Alejandro M. S. Mayer Abimael D. Rodríguez Orazio Taglialatela-Scafati Nobuhiro Fusetani 《Marine drugs》2013,11(7):2510-2573
The peer-reviewed marine pharmacology literature from 2009 to 2011 is presented in this review, following the format used in the 1998–2008 reviews of this series. The pharmacology of structurally-characterized compounds isolated from marine animals, algae, fungi and bacteria is discussed in a comprehensive manner. Antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral pharmacological activities were reported for 102 marine natural products. Additionally, 60 marine compounds were observed to affect the immune and nervous system as well as possess antidiabetic and anti-inflammatory effects. Finally, 68 marine metabolites were shown to interact with a variety of receptors and molecular targets, and thus will probably contribute to multiple pharmacological classes upon further mechanism of action studies. Marine pharmacology during 2009–2011 remained a global enterprise, with researchers from 35 countries, and the United States, contributing to the preclinical pharmacology of 262 marine compounds which are part of the preclinical pharmaceutical pipeline. Continued pharmacological research with marine natural products will contribute to enhance the marine pharmaceutical clinical pipeline, which in 2013 consisted of 17 marine natural products, analogs or derivatives targeting a limited number of disease categories. 相似文献