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1.
本文研究了氨苄青霉素、羧苄青霉素和头孢霉素等3种抗生素对火炬松愈伤组织的生长和分化及不定芽生根的影响。结果表明,头孢霉素最有利于愈伤组织的诱导和生长,羧苄青霉素最有利于芽的分化,氨苄青霉素降低了不定芽的生根频率。所有试验的3种抗生素提高愈伤组织的形成和芽再生,但降低了芽的生根频率。这些结果表明,选择合适的抗生素对优化火炬松遗传转化体系有重要作用。图3表4参25。  相似文献   

2.
Three antibiotics ampicillin, carbenicillin, and cefotaxime were evaluated for their effects on induction, growth, and differentiation of organogenic calli, as well as rooting of regenerated shoots of three Ioblolly pine (Pinus taeda L.) genotypes. Of the antibiotics administered, cefotaxime maximally increased the frequency of callus formation and growth rate of organogeni ccalli, carbenicillin maximally increased the frequency of shoot regeneration and the average number of adventitious shoots per piece of organogenic callus, ampicUlin maximally decreased the rooting frequency of regenerated shoots and mean number of roots per regenerated shoot, in comparison with antibiotic-free media. Compared with the control, ampicillin minimally increased the frequency of callus formation, cefotaxime minimally increased the frequency of shoot regeneration, and carbenicillin minimally decreased the rooting frequency of regenerated shoots in three Ioblolly pine genotypes tested. All three antibiotics increased the frequencies of callus formation and shoot regeneration, and reduced the rooting frequency ot regenerated shoots suggested that the establishment of an efficient Agrobacterium tumefaciens-mediated transformation protocol for stable integration of foreign genes into Ioblolly pine need to select a suitable antibiotic. This investigation could be useful for optimizing genetic transformation of conifers.  相似文献   

3.
火炬松纸浆材优良家系人工林修枝效应   总被引:2,自引:0,他引:2  
对7 a生火炬松优良家系(L—11)示范林进行修枝试验表明:修枝促进了林分生长,修枝3 a后,与对照相比树高生长增加了7.1%~14.1%,胸径生长增加了1.9%~7.4%,单株材积增加了9.98%-29.10%,林分蓄积量增加12.13-26.53 m3/hm2,其中促进林分生长效果最好的处理是修枝强度为50%;修枝降低了火炬松优良家系林木的尖削度,与对照相比,H/D值增加了5.1%~9.5%。  相似文献   

4.
不同密度年龄火炬松林生物量对比研究   总被引:3,自引:0,他引:3  
根据不同密度林分的资料,对下蜀森林生态定位站9年生火炬松人工林的生物量估测方程进行了比较,对比了不同密度火炬松林分的面积指数,并结合定位站研究的历史资料及其它报道,对不同林龄火炬松生物量及其在各组分的分配进行了研究。  相似文献   

5.
Loblolly pine (Pinus taeda L.) seeds from sources with a mild climate under maritime influence (North Carolina) required shorter moist chilling to achieve maximum germination vigor than seeds from sources with a harsher continental climate (Oklahoma). Solid matrix priming (SMP) for 6 d achieved as much as 60 d of moist chilling to improve rapidity, synchrony and completeness of germination for three of the four families studied. SMP after moist chilling increased the rapidity, synchrony and completeness of germination. The benefit of SMP was greatest for non-stratified seeds and the benefit decreased with length of moist chilling. In general, delaying planting for one week after SMP had minor effects on germination when seeds were kept in the SMP matrix at 4°C. Delayed planting after SMP can increase germination rapidity and synchrony of seeds that have received long moist chilling and reduce the benefit of SMP in non-moist-chilled seeds.  相似文献   

6.
湿地松、火炬松适应性分析   总被引:1,自引:0,他引:1  
在同样的立地条件和抚育条件下,在1~20 a内,湿地松的生长明显优于火炬松和马尾松。20~30 a内,国外松生长不如马尾松,而且对地力的适应性也不如马尾松。作为短轮伐期的速生丰产纸浆林,湿地松是适应性比较强的速生丰产的引进树种,但在立地差、集约度低或海拔高处应以本地树种马尾松为主。  相似文献   

7.
火炬松家系区域引种试验研究   总被引:1,自引:2,他引:1  
火炬松家系区域引种试验研究结果表明,火炬松家系的适应性和抗逆性较强,但不同家系间的遗传分化和适应环境的能力相差较大,家系与环境间存在明显的互作效应,不同家系在速生性、适应性和变异性上差异极显著。经综合评判,选出速生性、适应性和抗逆性强且变异性小的7个优良家系CT-4、CT-6、MG-1、亚林-1、浙长乐母树96、南屿-1和PM-2,在Ⅲ类以上立地和经营管理水平一般的条件下,这些家系的树高、胸径和材积年生长量分别可达0.7~1.2 m、1.2~2cm和0.002~0.007 m3,比湿地松和马尾松具有明显的增益优势,适宜作为用材林进一步引种栽培与推广示范。  相似文献   

8.
对15年生火炬松半同胞家系的生长和材性性状测定表明:火炬松家系树高、胸径、材积、木材基本密度、纤维素含量、管胞长度与宽度等具有显著的差异;在家系水平上,木材基本密度、纤维素含量、管胞长度与宽度和材积生长相关不明显.遗传力测定表明:家系生长性状与材性性状平均遗传力均较高,达到中等程度以上.对树高生长、胸径生长、木材基本密度、纤维素含量、管胞长度与宽度等性状进行年度相关、早晚期选择研究表明:火炬松家系的生长相关主要由遗传决定;树高从第5年开始,胸径从第4年开始与以后各年的相关系效均在0.7以上,表明以此为最低年龄进行早期选择有较大的可靠性;木材基本密度10年生与其后各年龄级的相关系数值趋于稳定,术材密度最低选择年龄为10年;木材纤维素含量11年生与其后各年龄级的相关系效值趋于稳定,木材纤维素含量的最低选择年龄为11年.  相似文献   

9.
对火炬松(PinustaedaL.)速生材5个高度木材的基本密度、年轮宽度、生长率、晚材率和管胞弦壁纤丝角进行系统测量、统计和分析,结果表明,木材基本密度随树干高度的增加而降低.但各高度之间的差异不显著;生长率从髓心向外,南北方向都是随年轮数的增加而减小,在高度上是随树干高度的增加而增大.但其差异性均不显著.晚材率与木材基本密度呈线性正相关,与纤丝角呈线性负相关;木材基本密度与纤丝角呈负相关;纤丝角与生长率呈正相关.其相关显著性均随树干高度的增加而减弱.这些规律,为火炬松速生材的有效利用和林木生长调控提供了理论依据.  相似文献   

10.
火炬松施肥效应的研究   总被引:2,自引:0,他引:2  
1992年开始实施的火炬松幼林施肥试验,4年的试验结果表明:火炬松幼林施肥效果显著,南方大部分地区土壤缺磷,宜提倡施磷,单施磷肥(50kg/hm2、100kg/hm2、200kg/hm2),4年生树高增益21.6%-28.0%。地径增益31.5%-39.8%,肥效指数为2.1-2.42;在施磷的基础上配合施氮,肥效更好,最佳的施肥组合及配比是每公顷100kgN、100kgP2O5,或者每公顷100kgN、100kgP2O5、100kgK2O配合施用,四年生树高可达3.26-3.33m,树高增益30.4%-33.2%,胸径可达5.61-5.82cm,胸径增益50.8%-56.5%。  相似文献   

11.
火炬松年抽梢1~7次,平均抽梢4次,以抽3~5次梢为主,占91.5%;家系间平均抽梢次数无显著差异,但家系×立地存在互作;抽梢次数与树高呈正相关,树高生长随抽梢次数增加而增加。逐步回归分析表明:当年抽高生长因子被选入所有不同抽梢次数的回归方程中,它是左右树高生长的重要因子;年内第3次抽梢长度也是影响树高生长的因子。它们能否充当早期预测指标,有待进一步研究。  相似文献   

12.
以多糖得率为指标,从火炬松松针中浸提多糖,并测定其体外抗氧化活性。在单因素试验基础上采用响应面法优化超声波辅助热水浸提火炬松松针多糖,最佳的工艺参数为:30 g松针粉末在超声波作用时间25 min,热水浸提1 h,液料比25∶1(m L∶g),热水浸提温度91℃。在此条件下,火炬松松针多糖得率达1.867%,提取率达91.39%。通过测定松针多糖对苯基苦基肼自由基(DPPH·)、羟基自由基(·OH)和2,2-联氮-二-(3-乙基-苯并噻唑-6-磺酸)自由基(ABTS+)的清除能力评价其体外抗氧化能力。结果显示:火炬松松针多糖对自由基DPPH·、·OH和ABTS+都有较强清除能力,且都呈较好的量效关系,火炬松松针多糖具有较强的体外抗氧化能力。  相似文献   

13.
对湖南同一立地指数(18)下,5株17.5年生的火炬松(PinastaedaL.)短周期工业材1.3,3.6,5.6,7.6,9.6m5个高度的木材干缩系数、基本密度、生长轮宽度、晚材率和微纤丝角度,按生长轮取样,进行了测量和统计分析.结果表明,弦向、径向、体积干缩系数和干缩比,在树于5个高度之间的差异,均达到了显著水平;各高度干缩系数与生长轮的年龄(离髓心的距离)以及与上述各主要构造因子之间呈显著的线性相关,且相关度度随树干高度的增加而减弱.  相似文献   

14.
表达耐盐基因的转基因火炬松的再生   总被引:2,自引:0,他引:2  
唐巍 《林业研究》2002,13(1):1-6
盐害是限制作物和树木分布和生产的重要因素。盐分过多导致细胞内水分缺失并影响许多重要的细胞代谢活动。本文利用火炬松作为模式植物建立了一套提高植物耐盐性的新技术。这一技术以火炬松合子胚为材料,利用农杆菌介导的转化方法将山犁醇脱氢酶和甘露醇脱氢酶基因转入火炬松。然后再生转化的愈伤组织和转基因植株。经DNA杂交证实的转基因植株被用于耐盐性试验,结果表明这些转基因的植株的耐盐性有明显的提高。这一技术对针叶树的遗传工程育种有重要的参考价值。图3表2参26。  相似文献   

15.
Dynamic changes in stomatal conductance and the rate of photosynthesis were measured as periods of shading (decrease in irradiance from 800 to 200 micro mol m(-2) s(-1)) between 5 and 60 min were imposed on needles of Pinus taeda L. trees under laboratory conditions. Shading induced a 39% decrease in stomatal conductance but the rate of change was slow. Average time constants (+/- standard error) were shorter for the decrease in stomatal conductance when shading was imposed for 30 min (14.8 +/- 1.3 min) than for the increase in stomatal conductance when shading was removed (25.5 +/- 3.4 min). The time constants for increasing stomatal conductance when shading was removed were linearly related to the length of the previous dark period. The rate of photosynthesis fell immediately by 58% when shading was imposed and increased more rapidly than the change in stomatal conductance when shading was removed. The increase in photosynthesis during the induction phase after shading was removed was limited by both stomatal and biochemical effects. The long time constants for stomatal response contributed to the poor correlations between stomatal conductance and instantaneous measurements of irradiance from field data. However, the slow response of stomatal conductance to changes in irradiance had little effect on total daily transpiration, carbon gain and water-use efficiency.  相似文献   

16.
唐巍 《林业研究》2001,12(3):147-152
培养于附加2,4-D、BA和KT的愈伤组织诱导培养基上的火炬松成熟合子胚在培养3-9周后形成白色、半透明、有光泽的粘性愈伤组织。这类愈伤组织形成于成熟合子胚的子叶,但当用NAA或者IBA代替愈伤组织诱导培养基中的2,4-D时,它的诱导频率明显降低。这种粘性愈伤组织在分化培养基上形成体细胞胚。体细胞胚经过去50μm ABA和8.5%PEG600处理后成为耐干化胚。扫描电镜观察表明,萌发处理36小时后,耐干化胚恢复到干化处理之前的状态且大小和形态正常,而不耐干化胚不能恢复到干化处理之前的状态且表面撕裂。过氧化物酶活性的分析结果表明,耐干化胚有更高的过氧化物酶活性。耐干化胚的高过氧化物酶活性可能与催化H2O2的分解和保护体细胞胚免受氧化的伤害有关。  相似文献   

17.
火炬松与马尾松混交造林效果分析   总被引:1,自引:0,他引:1  
通过对火炬松与马尾松混交造林成效的全面调查,分析不同坡向和坡位对火炬松与马尾松生长量的影响及其树种生长规律之间的差异,结果表明:在相同立地质量等级和相同经营措施条件下,坡向以半阳坡的火炬松和马尾松生长量最大,林分总蓄积量达157.521 m3/hm2,阳坡次之,阴坡最小;坡位以下坡的火炬松和马尾松生长量最大,林分总蓄积量达170.795 m3/hm2,中坡次之,上坡最小。火炬松的平均胸径连年生长量达0.97 cm,比马尾松高出6.4%,平均树高连年生长量达0.56 m,低于马尾松10.8%,平均单株材积连年生长量达0.135 2 m3,略高于马尾松0.6%。因而,火炬松适宜当地造林。  相似文献   

18.
Haywood  James D. 《New Forests》1999,18(3):263-276
Several mulches of natural, synthetic, or blends of natural and synthetic fibers were tested around newly planted loblolly pine (Pinus taeda L.) seedlings on a sheared and windrowed site in central Louisiana, USA. The vegetation was primarily winter annuals, some residual grasses and forbs, and sparse woody regrowth. Study 1 was rotary mowed just prior to planting in March 1992, and 35 mulches and an untreated check were established. In Study 2, 15 mulches and an untreated check were established in a 1-year-old rough in March 1993. In both studies, a single loblolly pine seedling formed each plot established in a randomized complete block design, with 10 blocks as replicates. Each block was planted with a separate open-pollinated loblolly pine family.Nearly all mulches had deteriorated to some extent after three growing seasons. Synthetic mulches were generally more durable than the natural or natural/synthetic mulches. Mulching eliminated the established vegetation and germinants, and vegetation did not readily reestablish following the deterioration of a mulch. The soil seed bank apparently was not sufficient to regenerate areas that were once covered with mulch and many of the natural materials deteriorated into a fibrous cover that acted like a natural litter layer. Both of these residual weed control effects -- insufficient soil seed bank and formation of a fibrous cover -- were important in stopping vegetation from reestablishing after a mulch had deteriorated. After three growing seasons, the loblolly pine seedlings generally grew better if mulches were used.  相似文献   

19.
火炬松优良家系纸浆材林定向培育技术研究   总被引:5,自引:0,他引:5  
通过对火炬松优良家系纸浆材示范林、试验林(包括苗木试验、密度控制、整地试验、抚育试验、施肥试验、修枝试验等)及相关资料进行系统分析研究,提出了由优良家系苗木的选择应用技术,立地与气候等主要生境选择应用技术,以及丰产栽培技术措施组成的火炬松优良家系纸浆材林定向培育技术。  相似文献   

20.
鲁山县火炬松造林技术探讨   总被引:1,自引:0,他引:1  
通过几年的育苗和造林试验,总结出了火炬松在北部分界上造林的关键技术措施和方法。  相似文献   

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