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101.
Previous studies showed that the yellow seed color gene of a yellow mustard was located on the A09 chromosome. In this study, the sequences of the molecular markers linked to the yellow seed color gene were analyzed, the gene was primarily mapped to an interval of 23.304 to 29.402M. Twenty genes and eight markers’ sequences in this region were selected to design the IP and SCAR primers. These primers were used to screen a BC8S1 population consisting of 1256 individuals. As a result, five IP and five SCAR markers were successfully developed. IP4 and Y1 were located on either side of the yellow seed color gene at a distance of 0.1 and 0.3 cM, respectively. IP1, IP2 and IP3 derived from Bra036827, Bra036828, Bra036829 separately, co-segregated with the target gene. BLAST analysis indicated that the sequences of newly developed markers showed good collinearity with those of the A09 chromosome, and that the target gene might exist between 27.079 and 27.616M. In light of annotations of the genes in this region, only Bra036828 is associated with flavonoid biosynthesis. This gene has high similarity with the TRANSPARENT TESTA6 gene, Bra036828 was hence identified as being the gene possibly responsible for yellow seed color, in our research. 相似文献
102.
Carotenoids are not only important to the plants themselves but also are beneficial to human health. Since citrus fruit is a good source of carotenoids for the human diet, it is important to study carotenoid profiles and the accumulation mechanism in citrus fruit. Thus, in the present paper, we describe the diversity in the carotenoid profiles of fruit among citrus genotypes. In regard to carotenoids, such as β-cryptoxanthin, violaxanthin, lycopene, and β-citraurin, the relationship between the carotenoid profile and the expression of carotenoid-biosynthetic genes is discussed. Finally, recent results of quantitative trait locus (QTL) analyses of carotenoid contents and expression levels of carotenoid-biosynthetic genes in citrus fruit are shown. 相似文献
103.
为漆树优良品种的选择以及灰色系统理论在林业林木品种评价上的运用提供参考,对毕节市8个漆树品种红漆大木、粉皮大木、灯台大木、红尖大木、肤胭皮、粉红皮、白杨皮、青杠皮等树皮解剖中6个主要性状与产漆量的关系进行灰色关联度分析。结果表明:漆树树皮解剖的单个性状对产漆量有直接影响,其中以漆汁道直径的大小关系最重要,直接关联度达0.7964;其次是活皮漆汁道单位面积与活皮厚度。从树皮解剖的综合性状看,漆树品种最好的依次是红尖大木>红漆大木>肤胭皮>灯台大木>白杨皮>粉皮大木>粉红皮>青杠皮。分析结果与实际生产基本一致,表明在林业生产中运用灰色关联分析进行综合评价是可行的。 相似文献
104.
[目的]探讨半夏茎腐病原菌对半夏产生侵害的生理学机制。[方法]采用实验室培养试验研究了不同浓度的半夏茎腐病原菌孢子对半夏幼苗叶片生理特性的影响。[结果]随着病菌孢子浓度的增加,叶片超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性先上升后下降,游离脯氨酸、可溶性糖和丙二醛(MDA)含量呈升高趋势,且与对照相比差异显著。[结论]试验结果为预防和治理半夏茎腐病提供了理论依据。 相似文献
105.
106.
Effects of spent mushroom substrates and inorganic fertilizer on the characteristics of a calcareous clayey‐loam soil and lettuce production
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We evaluated the effects of the addition of two types of spent mushroom substrate (SMS), SMS from an Agaricus bisporus crop (SMS1) and a mixture of SMSs from an A. bisporus crop and a Pleurotus crop (50% v/v each) (SMS2), on the characteristics of a calcareous clayey‐loam soil and the yield and nutritional status of lettuce (Lactuca sativa L.), relative to crops receiving mineral fertilizer (M) and a control (C) without amendment. The application of SMS, especially SMS1, improved soil fertility compared with C and M soils. Moreover, the use of these organic substrates as soil amendments did not harm the plants and gave yields similar to that obtained with mineral fertilizer. The nutritional contents of the lettuce plants were greater than or similar to those of the plants from treatment C or M, except for the plant tissue concentrations of K, Fe and Zn, which were significantly reduced by SMS application. However, this latter fact did not reduce the lettuce yield in the amended soils. Therefore, the use of SMSs as organic amendments contributes to residue utilization, in an environmentally friendly way, and to improved soil fertility and crop yield. 相似文献
107.
Sulfated polysaccharides produced by microalgae, which are known to exhibit various biological activities, may potentially serve as natural antioxidant sources. To date, only a few studies have examined the antioxidant bioactivity of red microalgal polysaccharides. In this research, the effect of different salts on the antioxidant activities of two red microalgal sulfated polysaccharides derived from Porphyridium sp. and Porphyridium aerugineum were studied in a soy bean-based infant milk formula. Salt composition and concentration were both shown to affect the polysaccharides’ antioxidant activity. It can be postulated that the salt ions intefer with the polysaccharide chains’ interactions and alter their structure, leading to a new three-dimensional structure that better exposes antiooxidant sites in comparison to the polysaccharide without salt supplement. Among the cations that were studied, Ca2+ had the strongest enhancement effect on antioxidant activities of both polysaccharides. Understanding the effect of salts on polysaccharides’ stucture, in addition to furthering knowledge on polysaccharide bioactivities, may also shed light on the position of the antioxidant active sites. 相似文献
108.
109.
Recently tef is attracting the attention of the modern food industry since it is a gluten-free grain encompassing highly appreciated nutritional advaxntages. As a relatively new raw material, little information on its handling and processing properties is available. Flowability, water sorption characteristics and thermal properties of flours from three Ethiopian tef varieties were studied. Wheat (whole and refined) and rice flours were included as references. Tef flours were less flowable than the reference flours and their flow properties were more sensitive to water activity changes. Tef flours led to sigmoidal sorption isotherms with estimated monolayer water content of 0.053 (BET model) and 0.057 (GAB model) g water/g dry solids. No significant differences among the three tef varieties were observed on their gelatinization enthalpies that were higher than that of wheat and similar to rice. The amylopectin recrystallization extent after 7 days of storage at 4 °C was significantly higher in tef than in wheat flour. 相似文献
110.
以多元醇为液化剂(m(聚乙二醇)∶m(丙三醇)=4∶1),浓硫酸为催化剂,对沙柳木粉进行液化试验。将所得的液化产物多次清洗得到不溶液化残渣,应用FTIR、XRD和SEM对液化残渣的化学成分、微观形貌进行表征研究。结果表明:沙柳木粉液化反应分为木粉分解阶段和液化产物缩聚两个阶段;反应30 min后得到的残渣的红外光谱特征峰大致相同。XRD分析表明,残渣中含有大量的Si O2,木粉液化时非结晶区首先被破坏而降解,残渣的结晶度升高;反应后期结晶区发生降解,残渣结晶度略有下降。SEM图像表明,随着反应的进行,残渣由纤维状变为尺寸更小的连在一起的块状堆积物。 相似文献