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101.
以岑溪软枝油茶(Cenxi soft branch Camellia oleifera)无性系林分为研究对象,分析幼龄期(2年生)、结果初期(5年生)和盛产期(8年生) 3种林分中土壤养分的变化特征及对细根生物量的影响。结果表明:3种油茶林分中土壤养分总量差异显著,2年生油茶林分中有机质和水解性氮含量最高,5年油茶林分中有效磷含量最高,8年生油茶林分中速效钾含量最高。水平方向上,4种土壤养分在不同林地中分布较为均匀;垂直方向上,4种养分主要分布在土壤中上层0~30 cm处,整体上元素含量随着土层深度的加深而减少。偏相关分析表明:水解性氮对细根生物量的作用主要表现在40~60 cm土层;有效磷细根生物量的影响主要体现在10~40 cm土层,表现为不同程度的正相关性;速效钾对细根生物量的影响主要体现在10~20 cm土层中,表现为显著的负相关。有机质和有效磷与细根生物量呈极显著相关。 相似文献
102.
[Objective] This study aims to identify quantitative trait loci (QTLs) associated with cotton fruit branch length by using the combination of bulked-segregant analysis (BSA) and next-generation sequencing (NGS) method. [Method] In this study, the cotton F2 segregating population was developed with the short branch line Sujimian 125 and long-branch variety Sikang 1 as cross parents. According to the average internode length of fruit branches in middle, extreme individuals in F2 population were divided into two groups to generate the bulked DNA samples. The whole-genome resequencing of two DNA bulks was applied to analyze the single nucleotide polymorphism (SNP) and insertion-deletion (InDel) between two groups, and the fruit branch internode length related QTLs were detected using Euclidean distance (ED). [Result] With SNP data obtained from sequencing, a 0.8 Mbp range associated region on chromosome A3 was identified; with InDel data obtained from sequencing, a 1.09 Mbp range associated region on chromosome A3 was identified. Two regions overlapped, and the overlapped range was 0.77 Mbp. [Conclusion] This result suggested that the difference between I-type fruit branch and zero-type was due to different genetic locus and pattern rather than dosage effect of the same gene. 相似文献
103.
垂枝作为特殊的林木形态结构,因形态优美在全世界被广泛用于绿化和园林景观而成为研究热点。国内外对垂枝植物的研究表明赤霉素在垂枝形成中起作用,但是垂枝形成的分子背景研究仍比较缺乏。本研究以旱垂柳(Salix matsudana var. pseudo-matsudana)的垂枝为研究对象,通过对旱垂柳在不同生长发育时期的叶片、茎尖和茎基部进行了转录组和数字表达谱测序研究,共获得71 474个Unigenes序列。将Unigenes与COG和KEEG数据库比对,与转录和信号转导机制相关的基因在旱垂柳中高度富集,最终确定8 359个差异表达的基因,其中427个基因与激素相关。进一步分析赤霉素相关基因得出,主要参与2条赤霉素合成途径,具有生物活性的GA4是合成途径中的主要产物,而且GA4在枝条中的含量显著高于GA1和GA3。参与赤霉素信号转导途径中的GID1B在旱垂柳中上调表达,以及在G1和G4生长期的表达量高于其他时期,而DELLA蛋白GAI在G2生长期以后下调表达,GID1B和GAI在旱垂柳的垂枝生长过程中可能起非常重要的作用。这些研究结果将有助于探索赤霉素在旱垂柳垂枝形成中的分子作用,可为林木形态的遗传改良提供基础理论依据。 相似文献
104.
Eva M. Oxford Flavia B. Giacomazzi N. Sydney Moïse Roberto A. Santilli 《Journal of Veterinary Cardiology》2018,20(3):204-212
This report describes transient trifascicular block in three cats presented with lethargy and inappetence, and elevated cardiac troponin I concentrations.The electrocardiogram (ECG) of cat 1 showed a sinus rhythm with pronounced first-degree atrioventricular (AV) block, right bundle branch block, and left anterior fascicular block. The ECG of cat 2 showed truncular left bundle branch block alternating with left anterior fascicular block coupled with prolonged PR intervals, second-degree heart block, and paroxysmal third-degree AV block. The ECG of cat 3 showed first-degree AV block with concomitant right bundle branch block. The diagnosis of trifascicular block was made when paroxysmal third-degree AV block was documented.All cats recovered with medical management within weeks. Each cat resumed a sinus rhythm. Elevated cardiac troponin I concentrations suggested myocarditis that improved. 相似文献
105.
The effects of elevated atmospheric CO2 concentrations on the nighttime respiration were examined for two sample branches of a hinoki cypress tree (Chamaecyparis obtusa) growing in the field with an open gas exchange system for a one-year period from July 1994 to June 1995. The branches were
of a similar size and located at a similar position within the crown. One branch was subjected to an elevated CO2 concentration of 800 μmol mol−1 and the other was subjected to ambient air which had a CO2 concentration of about 370 μmol mol−1. Nighttime respiration rate was higher in elevated CO2 level than in ambient CO2 level. The relationship between nighttime respiration and the corresponding nighttime air temperature was fitted by the exponential
function in every month of the year. The segregation of regression lines between the two CO2 treatments increased gradually as the seasons progressed during the treatment period. TheQ
10 values for nighttime respiration were lower in elevated CO2 (1.9 ≤Q
10 ≤ 3.7) than in ambient CO2 (2.4 ≤Q
10 ≤ 4.5) in every month of the year. TheQ
10 was inversely related to the monthly mean nighttime air temperature in both elevated and ambient CO2. The estimated daily nighttime respiration rate under both CO2 treatments had a similar seasonal pattern, which almost synchronized with the temperature change. The respiration ratio of
elevated CO2 to ambient CO2 increased gradually from 1.1 to 1.6 until the end of the experiment. Our results indicate that the CO2 level and the temperature have a strong interactive effect on respiration and suggest that a potential increase in respiration
of branches will occur when ambient CO2 increases. 相似文献
106.
A new type of sampler for dry deposition in a forest canopy was designed and tested to confirm its usefulness. The new sampler
is made of Teflon chips packed in a nylon net, and tied on a rod like a branch in the canopy. The validity and characteristics
of the new sampler were checked by comparing it with the conventional bucket sampler and the foliar extraction method using
hinoki (Chamaecyparis obtusa) trees. The comparison between the deposited amounts on the dummy branch and those on the bucket indicates that the dummy
could trap gaseous matter more effective than the bucket. From a comparison with the foliar extracting method, it is concluded
that the trapping of particulate matter by the new dummy branch is comparable to that of natural needle leaves. However, its
efficiency for gaseous matter is relatively small. This disadvantage should be improved by applying other materials to the
dummy. Moreover, it is found that the uptake of gas especially SO2 through the stomata is an important point in the discussion about dry deposition. To evaluate the amounts of dry deposition
in the forest canopy more precisely, combination with the additional method should be useful.
This study was supported in part by a grant-in-aid for Scientific Research from the Ministry of Education, Science, Sports,
and Culture, Japan. 相似文献
107.
留营养枝棉花根系生长发育与分布规律的研究 总被引:13,自引:4,他引:9
棉花根系建成是棉花高产、优质、高效的前提。本文针对留营养枝和整枝棉花在不同的种植方式、不同密度条件下进行了根系生长发育和分布规律研究,结果表明,(1)留营养枝棉花根系生长发育早,一般比整枝棉花早10~30d达到根系生长高峰期;(2)留营养枝棉花根系生长量大,峰值高,比整枝棉花最大根长密度高1.8~3.4mm·cm-2,即高14.4%~16.6%;(3)留营养枝棉花根系的生长速率大于整枝棉,一熟条件下可为整枝棉的3.2倍,达到0.99mm·cm-2·d-1;(4)留营养枝棉根系中后期易早衰。本文还研究讨论了留营养枝与整枝棉花根系在土壤中的分布规律。并针对留营养枝棉花根系的生长发育和分布特点,提出留营养枝棉花高产栽培中应注意早施肥、早浇水,而且肥、水量要比常规管理大,中后期应注重及时追施花铃肥和根外补肥,防止棉花早衰。这项研究对于制定棉花简化栽培规范化技术有一定的理论指导意义。 相似文献
108.
本试验对葡萄伤流期就地硬枝接方法进行了研究,并对其接穗的生长结果状况与绿枝接进行了对比。研究结果表明:葡萄于伤流期就地硬枝接,采取放伤流的措施成活率可提高到90%以上,其接穗的生长结果状况显著较绿枝接强。 相似文献
109.
110.
砂姜黑土区棉花不同叶枝留量对产量的影响 总被引:2,自引:0,他引:2
1997-1998年研究了砂姜黑土区不同叶枝留量对棉花产量的影响,结果表明,留叶枝与常规整枝相比单株成铃增多,铃重大,成铃时空分布合理,烂铃减少,优质铃增加,但不同叶枝留量效果不同,T4效果最好,皮棉增产31.5%,霜前花率提高16.6%。 相似文献