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51.
作物区域试验的目的就是要鉴定作物新品种(系)的生产潜力、稳产性及区域适应性,田间调查和室内考种的项目繁多,但试验结果往往是对参试品系产量进行排名,其他性状进行描述,缺乏一种能代表品系综合性状表现的总成绩。本研究把熵权法引入小麦区域试验,建立了小麦综合表现的评价指标体系,包括目标层,准则层和指标层,其中目标层为参试材料综合性状表现,准则层包括田间记载性状、籽粒性状和产量性状,指标层有16个指标构成。通过计算各指标权重值和转化值,进而计算出各指标的分数值,分数值代表了一个品系在区域试验中的综合表现,可用于参试品种(系)间的比较。研究结果表明熵权法引入小麦区域试验,对参试品种(系)的评价是客观的。 相似文献
52.
Due to the growing interest in Central and Eastern Europe on cropping of wheat in optional late autumn terms, called facultative, genetic research and field evaluation were taken on four spring cultivars: Tybalt (NL), Monsun (DE), Ostka Smolicka (PL) and Bombona (PL), currently being recommended by breeders. The PPD gene analyze, expression level of dehydrine genes (WCS120 and WDHN13) in cooling test, and qPCR for RNA isolation and analyses of WCS120 and WDHN13 gene expression at the BBCH12 stage of wheat were estimated. Molecular analysis of PPD-D1 gene confirmed the presence of photoperiod sensitive allele ppd-D1b in all tested genotypes. The highest level of NRE WCS120 gene was detected in cultivars Tybalt and Bombona. Two-year field experimental study assessed the growth, development and productivity of facultative and spring crops of studied cultivars. Based on our results from field experiments and result of molecular analysis of alleles of PPD-D1 gene, the tested genotypes can be considered as potentially facultative genotypes. 相似文献
53.
Cereal crops in the reproductive stage of growth are considerably more susceptible to injury from freezing temperatures than during their vegetative growth stage in the fall. While damage resulting from spring-freeze events has been documented, information on genotypic differences in tolerance to spring-freezes is scarce. Ninety wheat genotypes were subjected to a simulated spring-freeze at the mid-boot growth stage under controlled conditions. Spring-freeze tolerance was evaluated as the number of seeds per head at maturity after plants were frozen at −6 °C. Plants that froze, as confirmed by infrared (IR) thermography, died shortly after thawing and consequently the heads did not mature. Only in plants that had no visible freezing (super-cooled) were heads able to reach maturity and produce seeds. In plants that super-cooled four genotypes had significantly higher seed counts after being exposed to freezing than three with the lowest. In addition, significant differences between genotypes were found in whole plant survival among those that had frozen. Genotypes with high whole-plant freezing survival were not necessarily the same as the super-cooled plants with the highest seed counts. Spring-freeze tolerance was not correlated with maturity suggesting that improvement in freezing tolerance could be selected for without affecting heading date. Spring-freeze tolerance was not correlated with freezing tolerance of genotypes of plants in a vegetative state, either under non-acclimated or cold-acclimated conditions indicating that vegetative freezing tolerance is not a good predictor of spring-freeze tolerance. 相似文献
54.
A two-year field experiment was conducted to investigate the effects of foliar Zn combined with N or P on Zn concentration and bioavailability in wheat grain and its milling fractions under different soil N levels. At maturity, grains were harvested and fractionated into flour and bran for nutrient analysis. Both high soil N supply and foliar Zn-enriched fertilizer applications greatly increased Zn concentration and bioavailability in both whole grain and grain fractions. Compared with foliar Zn alone, foliar Zn combined with N increased Zn concentration and bioavailability, whereas foliar Zn combined with P decreased Zn concentration and bioavailability. However, foliar Zn combined with P slightly increased the protein concentration compared to foliar Zn alone. Protein concentration significantly increased, whereas phytate concentration decreased, in whole grain and flour, both in soil N and foliar Zn-enriched N treatments. Therefore, foliar Zn plus N (with appropriate soil N management) may be a promising strategy for addressing dietary Zn micronutrient deficiencies, especially in countries where flour is a significant component of the daily diet. 相似文献
55.
Excessive tillage compromises soil quality by causing severe water shortages that can lead to crop failure. Reports on the effects of conservation tillage on major soil nutrients, water use efficiency and gain yield in wheat (Triticum aestivum L.) and maize (Zea mays L.) in rainfed regions in the North China Plain are relatively scarce. In this work, four tillage approaches were tested from 2004 to 2012 in a randomized study performed in triplicate: one conventional tillage and three conservation tillage experiments with straw mulching (no tillage during wheat and maize seasons, subsoiling during the maize season but no tillage during the wheat season, and ridge planting during both wheat and maize seasons). Compared with conventional tillage, by 2012, eight years of conservation tillage treatments (no tillage, subsoiling and ridge planting) resulted in a significant increase in available phosphorus in topsoil (0–0.20 m), by 3.8%, 37.8% and 36.9%, respectively. Soil available potassium was also increased following conservation tillage, by 13.6%, 37.5% and 25.0%, and soil organic matter by 0.17%, 5.65% and 4.77%, while soil total nitrogen was altered by −2.33%, 4.21% and 1.74%, respectively. Meanwhile, all three conservation tillage approaches increased water use efficiency, by 19.1–28.4% (average 24.6%), 10.1–23.8% (average 15.9%) and 11.2–20.7% (average 15.7%) in wheat, maize and annual, respectively. Additionally, wheat yield was increased by 7.9–12.0% (average 10.3%), maize yield by 13.4–24.6% (average 17.4%) and rotation annual yield by 12.3–16.9% (average 14.1%). Overall, our findings demonstrate that subsoiling and ridge planting with straw mulching performed better than conventional tillage for enhancing major soil nutrients and improving grain yield and water use efficiency in rainfed regions in the North China Plain. 相似文献
56.
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58.
The extensigraph is particularly useful in characterizing dough viscoelastic properties; however, testing throughput for standard method is low due to the prerequisite for farinograph water absorption, long dough resting and milling to prepare large amounts of flour. Therefore, a rapid extensigraph method was developed that reduced sample size (165 g wheat) for milling and more than tripled throughput. Wheat is milled in Quadrumat Junior mill with a modified sieving system. The resulting flour (100 g) was mixed with a pin mixer at constant water absorption to allow the evaluation of wheat genotypes at the absorption level they are expected to perform. Dough was subsequently stretched by an extensigraph after 15 min of floor time and 30 min resting. Strong correlations for extensigram Rmax (r > 0.93), extensibility (r > 0.64) and area (r > 0.88) were found for the proposed method compared to the standard method. Mixing parameters (time and energy) obtained during dough preparation provided further information about dough strength and mixing requirement. By significantly reducing sample size requirement and increasing testing throughput, this rapid extensigraph method can be widely adopted in milling and baking industry and meets the need for a fast evaluation of dough strength in breeding trials. 相似文献
59.
以定州市为例,介绍了麦田杂草的主要种类,明确了长期单一使用麦田除草剂、小麦种子频繁调运、机械跨区作业等原因是影响麦田杂草种类和优劣势变化的主要因素,并针对杂草防治工作中出现的主要问题提出了防治对策。 相似文献
60.
小麦热激蛋白转录因子在热胁迫和耐热性产生的过程中发挥重要作用。为进一步了解小麦热激蛋白转录因子C亚家族,本研究采用全基因组信息保守结构域比对和进化聚类分析,共鉴定了24个小麦TaHsfC基因,并对TaHsfC亚家族成员染色体定位、基因结构、亚细胞定位、对应蛋白质的氨基酸特点、基因表达进行了分析。结果表明,24个TaHsfCs主要分布在5条染色体上,其中A基因组中有7个,B基因组中9个,D基因组中有6个,另外两个所在染色体位置不清楚。TaHsfCs含有0~2个内含子,其中 TaHsfC1亚族基因含有1~2个内含子, TaHsfC2亚族基因则含有0~1个内含子。聚类分析表明,小麦TaHsfC成员共分为 TaHsfC1和 TaHsfC2两个亚族。24个TaHsfCs成员全部定位于细胞核。在15%PEG模拟干旱条件下,干旱敏感品种矮抗58和耐旱品种晋麦47中有10个TaHsfC基因显著上调表达,其中 TaHsfC2亚族基因的表达量上调倍数均高于 TaHsfC1亚族基因(其中 TaHsfC2j和 TaHsfC2k未在晋麦47中检测到表达量)。本研究可为探索小麦热激蛋白转录因子C家族基因在小麦抗旱中的分子机制提供一定的理论支撑。 相似文献