长治地区金叶复叶槭硬枝扦插育苗试验

试验在长治地区进行,以金叶复叶槭为试材进行硬枝扦插育苗试验,结果表明,采用沙壤土扦插和地膜覆盖均可明显提高扦插成活率、扦插苗高度及地径生长量。     

不同树龄油茶林分中土壤养分的变化特征及对细根生物量的影响

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。     

The Identification of QTL Associated with Cotton Fruit Branch Length Suitable for Mechanized Harvest Utilizing BSA-seq

[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.     

Clinical and electrocardiographic presentations of transient trifascicular block in three cats

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.     

Effects of elevated CO2 concentration on the respiratory behavior of the branches of field-grown hinoki cypress (Chamaecyparis obtusa)

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.     

New sampler for dry deposition in forest canopy

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.     

杉木无性系在不同条件下扦插生根及生长的研究

对杉木无性系扦插繁殖的生根及生长能力与扦插基质、原株年龄、采穗部位、穗条长度、扦插深度和时间等相关因素进行研究,结果表明,在不同杉木无性系之间,扦插生根及生长能力存在极显著差异．扦插基质、原株年龄、采穗部位和穗长、扦插深度和时间,对杉木扦插成活有显著或极显著的影响：①蛭石插床有利于插穗生根,但苗高生长以混合土为基质的插床为好;②无性系的生根能力、苗高和根径的生长量与原株年龄的关系表现为1年生＞3～5年生＞15～20年生;③根径处插穗的生根率、侧根生长量及苗高,分别比苗高1／3处的插穗大11．8％～18．6％,3．4％～9．8％和14．7％～25．7％;④穗长以10～12cm为宜,扦插深度为穗长1／2为好,扦插时间选择在12月份为佳．     

葡萄伤流期就地硬枝接方法的研究

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。     

绿竹带蔸主枝扦插植株的生物学特性

试验对绿竹带蔸主枝扦插过程的生物学特性进行观察,结果表明,主枝在扦插45天后开始在枝蔸的根芽点上萌发出幼根,但通常根径纤细,不能形成完整根系。发笋在80天左右开始,竿（笋）蓖根芽点在6月初开始生根,发根和生长都较为迅速,且根径粗壮,并形成发达的根系。根据发枝和发笋植株生根的比较研究表明,绿竹带南主枝扦插成活率应以发笋率为标准。     

4个国外引进树种扦插试验初报

采用全光自动喷雾扦插育苗设备,进行欧洲云杉、白云杉、黑云杉、东部白松４个 国外引进成功树种半木质化嫩枝扦插试验,探讨了这４个树种的扦插育苗技术。沙质插壤上各树种生根率分别达欧洲云杉７７．５％、白云杉５２％、黑云杉４４．５％,东部白松在锯末插壤上扦插生根率为３５％。为进一步扩大栽培,加速林木良种化,走有性选择、无性繁育的无性系林业发展道路,提供了新的可行的无性繁殖方法。