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81.
播种方式对不同类型小麦品种产量性状的影响 总被引:10,自引:0,他引:10
在不同种植方式下,对豫麦18号、豫麦21号、豫麦49号、93中6等4个不同类型小麦品种的产量构成因素进行了研究。结果表明,等行距与宽窄行之间产量无明显差异,低播量、高播量下差异均达极显著水平。叶面积系数从开花到乳熟都呈下降趋势,只有93中6呈上升趋势,豫麦21号、豫麦49号、豫麦18号间无差异。豫麦18号灌浆速度最快,豫麦21号最慢,豫麦49号和93中6相比,前者前期灌浆快,后者一期灌浆快,93中6硝酸还原酶活性最高。豫麦18号次之,豫麦21号第3,豫麦49号最低。 相似文献
82.
云南普洱茶感官品质与内含成份关系研究 总被引:1,自引:2,他引:1
在云南不同地区选择具有一定生产规模的5家云南普洱茶生产企业,到厂现场进行普洱饼茶随机取样,共取样6个;在云南省农业科学院茶叶研究所进行感官审评,在云南农业大学普洱茶学院进行内含成份分析,研究云南普洱茶感官品质与内含成份的关系,为云南普洱茶的规范生产和持续健康发展提供参考。结果表明:水浸出物含量的高低直接影响普洱茶的品质,并与普洱茶的汤色、浓度、滋味密切相关;茶多酚含量相对较高的茶样其感官品质均高于茶多酚含量相对较低的茶样;咖啡碱含量和糖类物质含量对云南普洱茶的感官品质的影响不是主要因子,但可以适度增进云南普洱茶的内质。 相似文献
83.
Dawei Xue Youzong Huang Xiaoqi Zhang Kang Wei Sharon Westcott Chengdao Li Mingcan Chen Guoping Zhang Reg Lance 《Euphytica》2009,169(2):187-196
Salinity is a major abiotic stress to barley (Hordum vulgare L.) growth and yield. In the current study, quantitative trait loci (QTL) for yield and physiological components at the late
growth stage under salt stress and non-stress environments were determined in barley using a double haploid population derived
from a cross between CM72 (salt-tolerant) and Gairdner (salt-sensitive). A total of 30 QTLs for 10 traits, including tiller
numbers (TN), plant height, spikes per line (SPL), spikes per plant (SPP), dry weight per plant, grains per plant, grain yield,
shoot Na+ (NA) and K+ concentraitions (K) in shoot, and Na+/K+ ratio (NAK), were detected, with 17 and 13 QTLs under non-stress and salt stress, respectively. The phenotypic variation
explained by individual QTL ranged from 3.25 to 29.81%. QTL flanked by markers bPb-1278 and bPb-8437 on chromosomes 4H was
associated with TN, SPL, and SPP under salt stress. This locus may be useful in the breeding program of marker-assisted selection
for improving salt tolerance of barley. However, QTLs associated with NA, K, and NAK differed greatly between non-stress and
salt stress environments. It may be suggested that only the QTLs detected under salt stress are really associated with salt
tolerance in barley.
D. Xue and Y. Huang contributed equally to the article. 相似文献
84.
The genetic relationship between popping expansion volume and two yield components in popcorn using unconditional and conditional QTL analysis 总被引:2,自引:0,他引:2
Y. L. Li Y. B. Dong D. Q. Cui Y. Z. Wang Y. Y. Liu M. G. Wei X. H. Li 《Euphytica》2008,162(3):345-351
Popping expansion volume (PEV) is the most important quality trait in popcorn, while its germplasm is inferior to normal dent/flint
corn in yield. In this study, 259 F2:3 families, developed from the cross between a dent corn inbred Dan232 and a popcorn inbred N04, were evaluated for their PEV,
grain weight per plant (GWP) and 100-grain weight (100 GW) in two environments. The genetic relationship between PEV and GWP,
and 100 GW on individual gene loci were evaluated using unconditional and conditional QTL mapping methods. In total, five,
one and three unconditional QTL were identified for PEV, GWP, and 100 GW, respectively. The positive alleles of all QTL for
PEV were from N04, while positive alleles of all QTL for GWP and 100 GW were from Dan232. In conditional mapping, one and
two QTL failed to be detected, and all four additional QTL were detected. Nevertheless, three QTL were identified, which controlled
PEV independently from GWP/100 GW. They seemed to be potential candidates in popcorn breeding to increase PEV without decreasing
GWP/100 GW. The results suggested that for significantly correlated traits, the conditional QTL mapping method could be used
to dissect the genetic interrelationship between traits at the level of individual QTL, as well as reveal additional QTL that
were undetectable by unconditional mapping. 相似文献
85.
干酪乳杆菌LC2W细胞壁组分体外对巨噬细胞活性的影响 总被引:1,自引:0,他引:1
探讨干酪乳杆菌LC2W细胞壁组分体外对小鼠巨噬细胞功能的影响。以培养液单纯培养小鼠巨噬细胞系RAW264.7细胞作为对照,研究干酪乳杆菌LC2W细胞壁主要组分磷壁酸和肽聚糖对RAW264.7细胞代谢水平、吞噬中性红能力及释放NO的影响。不同浓度磷壁酸和肽聚糖对小鼠巨噬细胞RAW264.7细胞代谢MTT能力、吞噬中性红能力有明显增强作用,并呈一定的剂量效应,在相同质量浓度时,两种细胞壁组分激活巨噬细胞能力无显著差异。同时诱导产生NO量也随着浓度增大而增加,当浓度达到50μg/mL时,磷壁酸诱导能力显现出较高的水平。干酪乳杆菌LC2W细胞壁主要组分磷壁酸和肽聚糖能激活小鼠巨噬细胞RAW264.7细胞,提高其代谢水平及吞噬能力,同时可诱导具有杀瘤作用的活性因子,并具有一定的剂量效应。 相似文献
86.
Genotypic and environmental variation in crop yield. A method of estimating the interdependence of the components of yield 总被引:1,自引:0,他引:1
Summary Because yield components do not behave as independent attributes the conclusions derived from simple yield analyses are of limited value in plant breeding programmes. By calculating a function W of the variances and covariances of the yield components, it is possible to estimate, on a scale from 0 to 1, the degree to which the variations in yield components were independent of one another in any given experiment. By this approach examples of almost complete compensation among the components (W = 0), of mutual independence of the components (W = 0.5), and of additivity of the components (W = 1.0) have been discovered in original data and in the literature. Reasons, and possible applications for these findings are discussed. Investigations into the sampling properties of W are reported in an appendix. 相似文献
87.
Summary Diverse landraces of wheat, collected from the semi-arid (150 to 250 mm of total annual rainfall) Northern Negev desert in Israel were considered as a potential genetic resource of drought resistance for wheat breeding. These materials were therefore evaluated for their reponses to drought stress in agronomical and physiological terms. Up to 68 landraces, comprising of Triticum durum, T. aestivum, and T. compactum were tested in two field drought environments, in one favourable field environment, under post-anthesis chemical plant desiccation which revealed the capacity for grain filling from mobilized stem reserves, under a controlled drought stress in a rainout shelter and in the growth chamber under polyethylene glycol (PEG)-induced water stress. Biomass, grain yield and its components, harvest index, plant phenology, canopy temperatures, kernel weight loss by chemical plant desiccation, growth reduction by PEG-induced drought stress and osmotic adjustment were evaluated in the various experiments.Landraces varied significantly for all parameters of drought response as measured in the different experiments, which was in accordance to their documented large morphological diversity. Variation in grain yield among landraces under an increasing drought stress after tillering was largely affected by spike number per unit area. Kernel weight contributed very little to yield variation among landraces under stress, probably because these tall (average of 131 cm) landraces generally excelled in their capacity to support kernel growth by stem reserve mobilization under stress. Yield under stress was reduced with a longer growth duration of landraces only under early planting but not under late planting. Landraces were generally late flowering but they were still considered well adapted phenologically to their native region where they were always planted late.Landraces differed significantly in canopy temperature under drought stress. Canopy temperature under stress in the rainout shelter was negatively correlated across landraces with grain yield (r=0.67**) and biomass (r=0.64**) under stress. Canopy temperature under stress in the rainout shelter was also positively correlated across landraces (r=0.50**) with canopy temperature in one stress field environment. Osmotic adjustment in PEG-stressed plants was negatively correlated (r=–0.60**) with percent growth reduction by PEG-induced water stress. It was not correlated with yield under stress in any of the experiments. In terms of yield under stress, canopy temperatures and stem reserve utilization for grain filling, the most drought resistant landrace was the Juljuli population of T.durum. 相似文献
88.
89.
半高丛越橘果实香气成分的GC—MS分析 总被引:5,自引:1,他引:4
采用静态顶空和气相色谱—质谱联用技术,以半高丛越橘品种北陆、圣云和北蓝为材料,研究了半高丛越橘果实香气成分。结果表明,半高丛越橘以醇类、酯类、萜类和酮类物质为主。共检测出39种挥发性成分,其中北陆检测出16种,圣云17种,北蓝23种。2-甲基丁酸乙酯和β-芳樟醇是半高丛越橘的特征香气,构成了半高丛越橘特有的香气,同时乙酸丁酯、2-丁酮、D-柠檬酸为北陆的特征香气,丁酸乙酯、2-丁酮为圣云的特征香气,丁酸乙酯、乙酸己酯、己醛为北蓝的特征香气成分,品种间特征香气的差异形成了半高丛越橘品种间独特的风味。 相似文献
90.
发酵方法对柿果醋中香气成分的影 总被引:5,自引:2,他引:3
采用顶空固相微萃取法、结合气相色谱质谱联用技术,对自然发酵和常规发酵柿果醋中香气成分进行了分离与分析比较,分别从2种柿果醋中分离鉴定出挥发性化合物63种,均含有酯类、羧酸类、醇类、烃类、醛酮类、酚类及少量其他化合物.常规发酵柿果醋香气成分中含有酯类33.78%、醇类32.38%和烃类1.08%,高于自然发酵柿果醋的含量;自然发酵柿果醋香气成分中含有羧酸类61.25%、醛酮类9.66%和酚类6.13%,高于常规发酵柿果醋的含量.采用常规发酵法生产的柿果醋具有较好的感官质量. 相似文献