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81.
82.
针对北方地区核桃受晚霜危害制约生产效益的问题,在渭河平原中部选择避晚霜品种及适宜的授粉品种,对12个早实核桃品种物候期进行了观察.结果表明:不同早实核桃品种物候期各异.早实核桃各物候期(除展叶期)均与有效积温呈极显著正相关.“辽核3号”、“辽核4号”、“香玲”、“鲁光”、“扎343”、“维纳”、“吐来尔”、“强特勒”为雄先型品种;“西林2号”、“西扶2号”、“温185”、“中林5号”为雌先型品种.“西林2号”、“西扶2号”、“中林5号”、“维纳”、“吐来尔”和“强特勒”雌雄花期部分相遇;“香玲”、“鲁光”、“辽核3号”、“辽核4号”、“温185”、“扎343”雌雄花期不相遇;“西林2号”、“西扶2号”、“香玲”、“鲁光”、“扎343”可为“辽核3号”、“辽核4号”、“温185”授粉;“扎343”和“温185”可以相互授粉.“香玲”、“鲁光”、“扎343”的雌花期基本能避开晚霜危害;“维纳”、“吐来尔”、“强特勒”能避开晚霜危害,是渭北栽培核桃的首选品种. 相似文献
83.
Edita Gregová Ji í Hermuth Ján Kraic Ladislav Dotla il 《Genetic Resources and Crop Evolution》1999,46(5):521-528
Identity and present degree of genetic homogeneity and heterogeneity, respectively of 52 European wheat accessions, maintained in the collection of wheat genetic resources, have been characterized using analyses of glutenins by sodiumdodecylsulphate polyacrylamide gel electrophoresis (SDS-PAGE). Six of the analyzed wheat accessions were observed to be homogeneous, while 46 (88.5%) of them were heterogeneous in protein profiles. Heterogeneous accessions possessed 2 to 13 different protein lanes. Together, 17 high molecular weight glutenin subunit (HMW-GS) alleles have been found. The most frequent HMW-GS alleles at the Glu-A1, Glu-B1, and Glu-D1 complex loci were 1, 7+9, and 2+12, respectively. However, also low frequented HMW-GS alleles or allelic combinations, such as 7+15, 13+16, 20, 6, 7, and 9 were observed. Furthermore, another new allele encoding HMW glutenin subunit with relative molecular weight 98.6 kDa has been found in one of the lines of the cultivar Eritrospermum 917. The Glu-score in the examined accessions varied in broad range, some of the lines reached the maximum value 10. 相似文献
84.
利用作物模拟模型辅助决策小麦新品种推广初探 总被引:2,自引:1,他引:2
在田间试验和前人研究的基础上,以比较成熟的CERES-WHEAT模型为研究工具,以我国的主要作物小麦为研究材料,探讨了作物模型在区域试验和良种评价方面的潜在应用。目的在于应用作物模型的动态性和预测性功能,通过利用品种已有生理和遗传参数以及各地的气象、土壤资料,对冬小麦不同品种同一地点和同一品种不同地点的生育期、物候期、产量和产量构成因素进行模拟,并与实测值进行比较,最后对品种的生态适应性进行了综合评价。最终在品种产量表现和生态适应性等方面为品种区域试验和良种推广提供决策的依据,试图尝试用一条新的途径,辅助 相似文献
85.
In this study, we investigated the genetic variation of allelopathic potential, its grey correlation with important agronomic
characters, and rank analysis on allelopathic stability of fifteen wheat accessions commonly grown in arid regions of the
Loess Plateau in China. The genetic variation of allelopathic property in dryland winter wheat showed significant differences
between accessions. Allelopathic effects exhibited high heritability (55–95%) throughout the life cycle of wheat. Heritability
was highest in the tillering stage and weakest in the seed filling stage. Allelopathic potential varied and was discontinuous
throughout the wheat life cycle. Grey correlation analysis indicated a close relationship between allelopathic potential dependant
on growth phase and agronomic characters. Allelopathic expression during some growth periods induced a partial correlation
effect on some important agronomic characters that affected wheat yield. Allelopathic heritability and its degree of influence
on yield were more evident in the vegetative growth stage compared to the reproductive stage. A multiple linear regression
was built between allelopathic potential during different growth periods and agronomic characters pursued in wheat breeding.
Allelopathic potential had a linear effect on production traits cultivated in wheat breeding. When allelopathic intensity
varied from 0 to 1 in the reproductive stage, plant height ranged from 44 to 108 cm, spike length from 6.4 to 9.2 cm, number
of spikelets with seeds from 13.4 to 21.0, mean seed number per spike from 41.5 to 50.3 and thousand seed weight from 36.2
to 38.3 g. Based on rank analysis, we concluded that there was a synergistic relationship between allelopathic potential in
wheat and genetic, chemical and ecological factors. Triticum aestivum L. ‘No 6 Lankao’ and T. aestivum L. ‘No 22 Xiaoyan’ were identified as stable and relatively strong allelopathic accessions, whereas T. aestivum L. ‘Lankao 95–25’ was a stable but relatively weak allelopathic cultivar. Other varieties showed unstable allelopathic potential. 相似文献
86.
Nitrate‐N uptake from soil depends on root growth and uptake activity. However, under field conditions N‐uptake activity is difficult to estimate from soil‐N depletion due to different loss pathways. We modified the current mesh‐bag method to estimate nitrate‐N‐uptake activity and root growth of two oilseed‐rape cultivars differing in N‐uptake efficiency. N‐efficient cultivar (cv.) ‘Apex' and N‐inefficient cv. ‘Capitol' were grown in a field experiment on a silty clayey gleyic fluvisol near Göttingen, northern Germany, and fertilized with 0 (N0) and 227 (N227) kg N ha–1. In February 2002, PVC tubes with a diameter of 50 mm were installed between plant rows at 0–0.3 and 0–0.6 m soil depth with an angle of 45°. At the beginning of shooting, beginning of flowering, and at seed filling, the PVC tubes were substituted by PVC tubes (compartments) of the same diameter, but with an open window at the upper side either at a soil depth of 0–0.3 or 0.3–0.6 m allowing roots to grow into the tubes. Anion‐exchange resin at the bottom of the compartment allowed estimation of nitrate leaching. The compartments were then filled with root‐free soil which was amended with or without 90 mg N (kg soil)–1. The newly developed roots and nitrate‐N depletion were estimated in the compartments after the installing period (21 d at shooting stage and 16 d both at flowering and grain‐filling stages). Nitrate‐N depletion was estimated from the difference between NO ‐N contents of compartments containing roots and control compartments (windows closed with a membrane) containing no roots. The amount of nitrate leached from the compartments was quantified from the resin and has been taken into consideration in the calculation of the N depletion. The amount of N depleted from the compartments significantly correlated with root‐length density. Suboptimal N application to the crop reduced total biomass and seed‐yield formation substantially (24% and 38% for ‘Apex’ and ‘Capitol’, respectively). At the shooting stage, there were no differences in root production and N depletion from the compartments by the two cultivars between N0 and N227. But at flowering and seed‐filling stages, higher root production and accordingly higher N depletion was observed at N0 compared to N227. Towards later growth stages, the newly developed roots were characterized by a reduction of root diameter and a shift towards the deeper soil layer (0.3–0.6m). At low but not at high N supply, the N‐efficient cv. ‘Apex’ exhibited higher root growth and accordingly depleted nitrate‐N more effectively than the N‐inefficient cv. ‘Capitol’, especially during the reproductive growth phase. The calculated nitrate‐N‐uptake rate per unit root length was maximal at flowering (for the low N supply) but showed no difference between the two cultivars. This indicated that the higher N‐uptake efficiency of cv. ‘Apex’ was due to higher root growth rather than higher uptake per unit of root length. 相似文献
87.
Philippe Quevauviller 《Journal of Soils and Sediments》2001,1(3):175-180
Single and sequential extraction procedures are often used to study the environmental fate of trace elements from soils and
sediments. Although these schemes are quite popular, they are prone to various sources of errors, which require them to be
thoroughly controlled. Owing to their operationally-defined character, the only way to compare analytical data is to stick
closely to procedures that have been collaboratively studied and written in the form of an operating protocol. Groups of scientists
have hence developed ‘harmonised’ procedures that are used as a reference for fractionation studies. A higher level is the
formal standardisation of the procedures by official standardisation bodies, which also fulfils the need for achieving the
comparability of data obtained by different laboratories from different countries. This paper discusses aspects of harmonisation
(consensus obtained by groups of scientists) and standardisation (adoption of standards as mandated by an international organisation)
as applied to single and extraction schemes for trace element fractionation studies, including quality control aspects. 相似文献
88.
四川省近10年审定普通玉米品种主要性状分析 总被引:1,自引:0,他引:1
对2005-2014年四川省审定的226个玉米品种的产量、8个农艺性状和5个品质性状进行统计分析,并对其变化趋势进行分析.结果表明,10年间四川省审定的玉米品种平均每667 m2产量为536.66 kg,产量优势不突出;平均生育期、平均株高、平均穗长、平均行粒数、平均穗行数、平均穗位高、平均百粒重、平均出籽率分别为123.26 d、262.96 cm、19.54 cm 、36.45粒、16.32行、104.92 cm、30.78 g、85.35%,年际间差异不大;平均容重为736.66g/L,高于国家一级标准;平均粗蛋白质含量、平均粗淀粉含量、平均粗脂肪含量、平均赖氨酸含量分别为9.99%、73.93%、4.53%、0.31%,整体营养水平不高.指出四川省玉米品种选育应根据生产需要选择适宜当地生态条件的区域品种,继续加大高产、优质玉米新品种选育的投入力度. 相似文献
89.
[目的]在膜下滴灌条件下,分析我国"花育"系列花生的主要农艺性状和产量潜力,为"十三五"新疆花生新品种选育提供核心亲本材料。[方法]采用田间试验与室内分析相结合的方法对16个"花育"系列花生品种进行系统研究,并对不同品种的主茎高、侧枝长、单株结果数、百果重、百仁重、荚果长、荚果宽等主要农艺性状和产量进行比较与分析。[结果]在膜下滴灌栽培条件下,"花育"系列花生品种的各个农艺性状得到充分发挥,其表现要优于在山东地区的种植,产量均有一定程度的提高,但不同品种之间在农艺性状和产量上也存在着一定的差异。其中,花育22号、花育28号和花育50号的单株生产力较高,花育33号和花育50号的产量较高,且综合性状表现优良。[结论]在新疆花生高产育种中,花育33号和花育50号可作为骨干亲本重点使用,并且在膜下滴灌条件下,其产量潜力还可进一步挖掘。 相似文献
90.
河南省中部地区优质小麦品种比较研究 总被引:14,自引:0,他引:14
[目的]大力发展优质专用小麦对满足市场需求,提高小麦市场竞争力具有重要意义。[方法]该研究对河南省小麦产业技术体系提供的12个优质小麦品种的产量和品质进行比较并对其抗逆性等进行鉴定。[结果]所有参试品种的越冬性较好,均无明显冻害发生。参试品种中,除师栾02-1和宿553的植株较高,部分发生倒伏外,其余品种均未发生倒伏现象。参试品种中只有宿553和矮抗58的均产高于对照(周麦18),增产率分别为10.97%和1.57%,其中宿553分蘖较强,较耐后期高温,生育期偏长,成穗率、穗粒数和千粒重均较高,产量三要素协调,均产达到7 075.5 kg/hm2,但植株偏高,易发生倒伏。DA7200型近红外分析表明,郑麦366、师栾02-1、新麦26、丰德存麦1号和郑麦3596等品种的品质指标均达到优质强筋标准。[结论]参试品种中丰德存麦1号、郑麦366和郑麦3596等品种综合性状表现较好,适宜在河南省中部地区推广种植。 相似文献