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1.
Seedlings of two fast- and two slow-growing families of slash pine, Pinus elliottii Englm. var. elliottii, were grown in a greenhouse for one growing season in one of 10 nitrogen (N) regimes. Increasing the N concentration in the nutrient solution resulted in both increased growth rates during the exponential growth phase and extended duration of the growing season. The two components of total height, free growth (epicotyl length to the first bud) and summer growth (height growth after the first bud), both increased significantly with increasing N concentrations up to 40-60 mg l(-1) but decreased at N concentrations above 180 mg l(-1). Compared to seedlings grown in the presence of an optimum N concentration, seedlings grown in the presence of trace amounts of N were smaller and had less summer growth as a percentage of total growth, earlier cessation of height growth, fewer flushes, lower shoot/root ratio, higher root fibrosity, and lower N concentrations in all seedling tissues. Compared to slow-growing families, fast-growing families had more summer height growth, more flushes and later growth cessation, higher shoot/root ratios and higher root fibrosity at all N concentrations. In the presence of an optimum or higher concentration of N, the fast-growing families also had higher needle and total N concentrations than the slow-growing families. Strong family by N-treatment interactions occurred for height, phenology and biomass traits because of the extra responsiveness of one family to increasing N concentration. Several seedling traits were identified that appear promising for predicting field performance in slash pine. The results indicated that the nutrient environment greatly influences genetic expression (e.g., family patterns of summer growth were most closely related to field rankings for seedlings in the trace-N treatment). 相似文献
2.
《Scandinavian Journal of Forest Research》2012,27(4):320-331
Genetic variation in adjacent Nordic populations of Acer platanoides L. and Betula pendula Roth was assessed by allozymes and in growth and phenology traits of juvenile trees grown in two field trials, and in growth chambers with free or restricted nutrient access. The objectives, based on the difference in the species' life-history traits, were to test the following hypotheses: (1) the population differentiation is higher in A. platanoides; (2) the genetic variability and (3) the phenotypic plasticity are larger in B. pendula. Analyses of variance revealed that, except for budburst, the growth and phenology traits generally supported the first hypothesis. The estimates of the coefficients of additive variance consistently disagreed with the second hypothesis. Allozyme data also supported the first hypothesis, but not the second. Finally, the phenotypic plasticity was larger in B. pendula. 相似文献
3.
Hawkins BJ 《Tree physiology》2007,27(6):911-919
Nitrogen (N) uptake and utilization in seedlings of six full-sib families of coastal Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) known to differ in growth rate were assessed at the whole plant and root levels. Seedlings were grown in soil or aeroponically with high and low nutrient availability. Consistent family differences in growth rate and N utilization index were observed in both soil and aeroponic culture, and high-ranking families by these measures also had greater net N uptake in soil culture. Two of the three families found to be fast-growing in long-term field trials exhibited faster growth, higher N utilization indices and greater net N uptake at the seedling stage. Mean family net influx of ammonium (NH4+) and efflux of nitrate (NO3-) in the high- and low-nutrient treatments were significantly correlated with measures of mean family biomass. The high-nutrient availability treatment increased mean net fluxes of NH4+ and NO3- in roots. These results indicate that efficiency of nutrient uptake and utilization contribute to higher growth rates of trees. Nutrient-related traits should be considered in tree breeding programs, as the indications are that assessments may be made at an early stage. 相似文献
4.
Individual and family heritabilities and juvenile–mature genetic correlations were estimated for growth and biomass traits
recorded in treatment with optimal and limiting water and/or nutrient availability to study how the different growth environments
affected genetic parameter estimates. Thirty open-pollinated families, randomly selected among the 58 families used in field
progeny tests in Galicia, were cultivated for 30 weeks in a climatic chamber under controlled conditions. Two water regimes
(high and low water supply) combined with two nutrient regimes (high and low nutrient supply) were applied by subirrigation.
Several growth, branching and dry mass traits were assessed 30 weeks after sowing and compared with field performance (height,
diameter and volume) of 4-year-old progeny tests established at three different sites in Galicia (NW Spain). Both the irrigation
and the fertilization treatments had a strong effect in all the assessed traits except irrigation for the number of branches.
Heritabilities for growth and biomass traits were moderate to high (0.13–0.77) in individual treatments. However, when analyzing
all treatments together, the impact of the family × treatment interactions led to a reduction (0.20–0.35) in the heritability
estimates. The results indicated that the genotype × water and genotype × nutrient interactions may be important and could
not be ignored in the Galician radiata pine breeding program. Climatic chamber–field correlations were different between different
traits measured at climatic chamber experiments and the three field tests. The correlations were larger with the well-watered
treatments, suggesting that further development of early testing methods for radiata pine in Galicia should include treatments
with no limiting water availability. 相似文献
5.
《Scandinavian Journal of Forest Research》2012,27(3):196-205
Growth and nutrition of hydroponically cultivated pine seedlings (Pinus pinaster Ait.) were investigated at various phosphorus (P) availabilities. P was added either with free access or at a relative addition rate of 0.02 and 0.04 day?1. Laboratory observations were compared with adult growth performances in the field in two sets of experiments: the first with three contrasting populations, the second with seven full-sib families within a population. Significant differences in P productivity (growth rate per unit P in the plant) and in maximal relative growth rate were observed in both experiments, but correlation with adult performances was restricted to populations. Selection for nutrient-related traits would thus be possible, but understanding of the relationship between growth and nutrition needs further evaluation. The minimum P concentration in the seedlings supporting maximum growth ([P]optimum) varied from 2.2 to 3.8 mg g?1 DM, which is in agreement with values obtained in other species. The root/shoot ratio increased with P limitation, with a marked tendency for the population with the highest adult height performance. Inversely, within families, seedlings identified as the best performers for adult growth invested more biomass in shoots than in roots with P stress. 相似文献
6.
[目的]对南方红豆杉家系进行了生长节律变异研究,以选育优良速生的南方红豆杉家系.[方法]在江西分宜、湖北京山、浙江淳安和浙江龙泉4个地点对2年生南方红豆杉家系容器苗进行了苗期遗传测定和苗高生长节律观测,分析了其性状变异的家系效应、地点效应及家系×地点的互作效应.[结果]表明参试的南方红豆杉苗高、地径和苗高生长节律参数在家系间、地点间和家系×地点间均表现出极显著差异.南方红豆杉家系间苗高最大值分别高出最小值76.20%(江西分宜)、52.98%(湖北京山)、55.42%(浙江淳安)和78.10%(浙江龙泉);地径最大值分别高出最小值126.67%、23.68%、37.02%和26.48%.南方红豆杉家系间苗高和地径变异系数在11.81%~26.50%之间.对南方红豆杉2年生容器苗各性状进行遗传力估算,遗传力在0.80~0.97之间.相关性分析认为不同测试点间苗高与苗高生长节律参数具有不同相互关系,江西分宜点苗高与线性生长速率呈负相关,而浙江龙泉点苗高与线性生长速率则呈显著正相关.以苗高作为主要性状指标,从4个测试点中筛选出7个南方红豆杉优良家系.[结论]南方红豆杉家系间,苗高、地径与苗高生长节律具有较丰富的遗传差异,遗传改良潜力较大,家系各性状遗传力较大,受较强的遗传控制,早期选择有一定的可靠性.家系与地点的互作效应显著说明部分家系生长受环境因素影响较强,遗传稳定性较弱;其中闽11和三元06两个优良家系在4个测试点中均被选中,遗传稳定性较强,可在多点进行推广. 相似文献
7.
Tran D Hung Jermey T Brawner David J Lee Roger Meder Mark J Dieters 《Southern Forests》2016,78(3):225-239
Ten growth or wood-quality traits were assessed in three nearby Corymbia citriodora subsp. variegata (CCV) open-pollinated family-within-provenance trials (18 provenances represented by a total of 374 families) to provide information for the development of a breeding program targeting both pulp and solid-wood products. Growth traits (diameter at breast high over bark [DBH], height and conical volume) were assessed at 3 and 7 years of age. Wood-quality traits (density [DEN], Kraft pulp yield [KPY], modulus of elasticity [MoE] and microfibril angle [MfA]) were predicted using near-infrared spectroscopy on wood samples collected from these trials when aged between 10 and 12 years. The high average KPY, DEN and MoE, and low average MfA observed indicates CCV is very suitable for both pulp and timber products. All traits were under moderate to strong genetic control. In across- trials analyses, high (>0.4) heritability estimates were observed for height, DEN, MoE and MfA, while moderate heritability estimates (0.24 to 0.34) were observed for DBH, volume and KPY. Most traits showed very low levels of genotype × site interaction. Estimated age–age genetic correlations for growth traits were strong at both the family (0.97) and provenance (0.99) levels. Relationships among traits (additive genetic correlation estimates) were favourable, with strong and positive estimates between growth traits (0.84 to 0.98), moderate and positive values between growth and wood-quality traits (0.32 to 0.68), moderate and positive between KPY and MoE (0.64), and high and positive between DEN and MoE (0.82). However, negative (but favourable) correlations were detected between MfA and all other evaluated traits (?0.31 to ?0.96). The genetic correlation between the same trait expressed on two different sites, at family level, ranged from 0.24 to 0.42 for growth traits, and from 0.29 to 0.53 for wood traits. Therefore simultaneous genetic improvement of growth and wood property traits in CCV for the target environment in south-east Queensland should be possible, given the moderate to high estimates of heritability and favourable correlations amongst all traits studied, unless genotype × site interactions are greater than was evident. 相似文献
8.
Variation of traits that include height, diameter at breast height (DBH), stem volume, crown width, straightness, wood basic
density, tracheid length and width of open-pollinated progenies from clonal seed orchard of Pinus massoniana was analyzed. Differences in traits such as growth, tree form and wood quality among families was significant, which indicated
that the improvement potential was notable. Heritability of height and wood basic density reached 0.691 and 0.640, respectively.
According to a correlation analysis between traits, stem straightness could be improved indirectly when growth traits are
improved; growth traits were significantly correlated with wood basic density; and wood basic density was not significantly
correlated with length and width of the tracheid. Under the selection ratio of 10%, genetic gains were 19.74% and 19.32% respectively,
and selected families from the progeny test stands at the age of five years and eight years were the same. Genetic correlation
of height, DBH and stem volume was also significant at the level of 0.01. These show that selection of the short rotation
of P. massoniana for pulp and paper use would be efficient for five-year-old trees. According to the comparison of the heritability of all
the traits and taking into account the result of canonical correlation analysis, height could be considered as the most important
index for selection. Given wood quality of all the families, and flowering and fruit settings of the clones in a seed orchard,
twelve fine families were selected at 10% selection ratio of height growth and stem volume.
Translated from Scientia Silvae Sinicae, 2005, 41(6): 43–49 [译自: 林业科学] 相似文献
9.
10.
Genetic parameters were estimated for yield of 1,8-cineole and total monoterpenes as a fraction of leaf weight in nineteen open-pollinated families of Petford origin at 3.75 years in two progeny/provenance trials of E. camaldulensis in Zimbabwe. Both traits appear to be highly heritable and, as expected, were strongly genetically correlated, with narrow-sense individual heritabilities near 0.50. Expected gain in the first generation following individual selection in the trials of one tree in 10 for either trait is about 25–32%.Genetic correlations between growth traits and 1,8-cineole yield were small. This indicates that both traits might be improved concurrently thus enhancing the economics of growing Petford E. camaldulensis for wood and medicinal oil. However, the presence of moderate and unfavourable genetic correlations between growth traits and total yield of monoterpenes warrants further study. It was not possible to gauge the significance of apparent family × site interaction for 1,8-cineole yield in this study. However, a test of rank correlation showed an association (Ip<0.01) between family rankings on each site and the highest-yielding trees on both sites came from the same families. This raises the possibility of being able to select individuals for cloning that yield well over a range of site conditions. 相似文献
11.
12.
Lack of association between allozyme heterozygosity and juvenile traits in Eucalyptus 总被引：2，自引：0，他引：2
Genetic variability for juvenile traits, which included basal diameter, height, biomass accumulation, and growth increment, was studied in eight provenances involving four species, Eucalyptus grandis, E. saligna, E. camaldulensis and E. urophylla, under uniform greenhouse conditions. The species differed significantly for all juvenile traits including individual mean allozyme heterozygosity, and high levels of variability were observed within and among species, which indicated that scope for selection exists for these traits. There was considerable reduction in genetic variability for all traits at 6 months of age when compared to that observed at 4 months. Eucalyptus saligna recorded the highest mean for basal diameter and biomass accumulation, while E. camaldulensis exhibited the highest mean for height. The two E. camaldulensis provenances exhibited the highest individual mean heterozygosities (0.425 and 0.417), followed by E. saligna (0.296 and 0.258), E. urophylla (0.254 and 0.233), and E. grandis (0.300 and 0.163). The juvenile traits were correlated with individual mean allozyme heterozygosity to examine the possibility of developing a genotypic basis for early selection of potentially superior individuals in a tree improvement program. 相似文献
13.
[目的]在土壤有效P匮乏的立地条件下,揭示针叶N、P含量及其化学计量比与马尾松生长性状的相关性。[方法]以马尾松二代育种群体内30个无性系为试验对象,野外调查11年生时马尾松二代无性系树高、胸径等生长性状与针叶N、P含量及其化学计量比的相关性。[结果]结果表明:(1)各生长性状在马尾松二代无性系间差异显著,且无性系重复力较高,均达到0.95以上。马尾松成熟针叶和当年生针叶N、P含量及N/P在二代无性系间差异均达显著水平;(2)相关分析表明,马尾松二代无性系树高、胸径与成熟针叶和当年生针叶N含量、N/P均呈显著或极显著正相关,与成熟针叶N/P的相关系数分别为0.608 6和0.542 8,与当年生针叶N/P的相关系数分别为0.515 9和0.679 2;(3)基于主要生长性状、针叶N和P含量及其化学计量比,可将30个马尾松二代无性系聚为4类:类群1无性系树高、胸径等生长表现优良,成熟针叶N/P较高,而当年生针叶N/P相对较低;类群2无性系树高、胸径等生长表现较好,成熟针叶和当年生针叶N/P值在30个无性系中居中间水平;类群3占试验无性系总数的一半,树高、胸径等生长表现一般,成熟针叶与当年生针叶N/P相差较大,大部分无性系成熟针叶N/P较低,而当年生针叶N/P相对较高;类群4树高、胸径等生长表现较差,成熟针叶和当年生针叶N/P均较低。[结论]在贫P立地下,马尾松二代亲本无性系C13(7750×1126)和C14(3201×1123)各生长指标均较高,可能是通过调整当年生针叶和成熟针叶的养分分配,增加了当年生针叶对限制其生长的P素的再利用和再吸收,促进了N素的吸收,调整了当年生针叶和成熟针叶的N/P,以形成特定的养分分配机制。 相似文献
14.
[目的]通过对思茅松自由授粉子代测试林的生长与形质性状遗传参数的估计,进行优良家系选择,为建立思茅松高世代种子园及培育优良无性系苗木提供种质资源。[方法]采用随机区组试验设计,在214个思茅松自由授粉家系子代测试林中选择胸径、地径、树高、枝下高、冠幅、通直度、树干圆满度、树冠圆满度、材积及地上生物量等生长与形质性状,利用线性混合模型进行遗传参数的估计,进行优良家系筛选。[结果]思茅松自由授粉子代测试林生长与形质性状的遗传参数在家系间差异极显著。各性状的家系遗传力较高,其中,地径的家系遗传力最大(1.105)。材积的预期遗传增益高于地上生物量,利用家系/家系内选择方法进行优良家系的筛选,材积的预期遗传增益为60.75%,入选家系为60个;地上生物量的预期遗传增益为44.22%,入选家系为66个。轮盘数、通直度和树干圆满度对材积和地上生物量都有显著影响。[结论]在早期选择中,形质性状的遗传变异对思茅松自由授粉优良家系的选择有重要参考作用,4年生思茅松自由授粉家系子代测试林中各性状存在着丰富的遗传变异,在早期选择中可以筛选出适合不同培育目标的优良家系,最大限度挖掘其遗传潜力。 相似文献
15.
Catherine Ky-Dembele Mulualem Tigabu Jules Bayala Per Christer Odén 《Agroforestry Systems》2014,88(2):311-320
Within- and between-provenance variations in seed and seedling traits of Khaya senegalensis A. Juss were studied at INERA in Burkina Faso. Nursery grown seedlings from four provenances in Burkina Faso were used for the study. The studies revealed significant variability in all traits evaluated. Seed length and weight significantly varied among provenances and families within provenances, where Bopiel and Koyenga had the highest mean values. Height and root collar diameter of 1 year old seedlings significantly varied among families within provenances. Except leaf biomass ratio and carbon isotope ratio which varied significantly among provenances but not among families within provenances, all other seedling biomass traits—total plant biomass, stem biomass ratio, leaf biomass ratio, root biomass ratio, root shoot ratio, specific leaf area, and leaf area ratio were significantly affected by provenances and families within provenances. The magnitude of variation due to family effect ranged from 65 to 93 % for seed size traits, and from 4.5 to 17.8 % for seedling characters. Estimates of family heritability were moderate to high (0.67–0.95) for seed traits, but low to moderate (0.19–0.59) for seedling characters, indicating that much of the total variation in seed traits is due to the genetic effect. The two most prominent provenances, Koyenga and Bopiel, with higher seed size and greater seedling growth could be considered for an eventual K. senegalensis improvement program in Burkina Faso. 相似文献
16.
Effects of nitrogen on leaf physiology and growth of different families of loblolly and slash pine 总被引：4，自引：0，他引：4
Leaf physiology and fractional dry weight allocation were examined in four open-pollinated families of loblolly pine (Pinus taeda L.) and slash pine (Pinus elliottii Englm. var. elliottii) in response to growth under low and high N supply for six months. Nitrogen greatly influenced dry weight allocation, total mass, leaf net photosynthesis and leaf conductance in seedlings of both species. Family variation in fine root allocation was observed under low but not high N treatment, but for the majority of physiological and growth traits, family variation was stable under varying N treatment. Family rankings based on juvenile height, diameter and biomass accretion were similar to rankings based on field performance at 22 years in slash pine but not loblolly pine. Lower leaf maintenance respiration rates were associated with families exhibiting the most rapid juvenile growth. 相似文献
17.
Pot experiments are often performed to assess plant physiological traits and relationships among growth traits under controlled environments. However, the reliability of pot studies for predicting the growth and performance of trees in the field has rarely been rigorously assessed. We evaluated the suitability of pot experiments for predicting field performance, measured as shoot biomass production, by investigating determinants of growth in hybrid willows (Salix spp.) grown under various environmental conditions in the field, and by comparing the data with the results from a corresponding pot study. Biomass production in six hybrid willow clones, bred for use as bio-fuels, was assessed in three field trials located in central and southeastern Sweden throughout the first 3-year cutting cycle. The determinants of biomass productivity, measured as biomass allocation and nitrogen (N) economy, were identified in one of the field trials. Key traits for shoot biomass production in the field were total leaf area and total amount of N; plant N losses by shed leaves were only partly controlled by leaf-litter N concentration. These key traits were also obtained from the pot study and related to shoot biomass production and abscission-leaf N loss in the field. Total leaf area and total N pool of plants grown in pot experiments were good predictors of long-term biomass production in the field, whereas shoot biomass production, specific leaf area and tissue N concentration of pot-grown plants were less suitable as predictors of field performance. Relationships between the key traits and shoot biomass production were clone-specific, indicating the need for analysis of growth traits at the clone level if field performance of trees is to be evaluated based on data from pot studies. Nutrient loss components are important for tree performance in the long term and evaluations of nutrient loss characteristics at the individual-tree level should focus on nutrient pools lost rather than on nutrient concentrations in abscised plant parts. 相似文献
18.
Variations in several growth, gas exchange and leaf traits among greenhouse-grown black locust (Robinia pseudoacacia L.) seedlings from 11 half-sib families were investigated. Three weeks after germination, early growth rates ranged from a minimum of 1 cm d(-1) in the slowest growing family, to a maximum of 3 cm d(-1) in the fastest growing family. Significant family variation in net photosynthetic rate per unit leaf area (P(N)), stomatal conductance, chlorophyll content, height, diameter, stem dry weight and total dry weight was observed. Net photosynthetic rate declined with seedling age. Net photosynthetic rate per unit leaf area was significantly correlated (r < 0.4) with specific leaf area, total chlorophyll, root dry weight, foliage dry weight and total dry weight. The correlation coefficients were higher (r >/= 0.55) between P(N) x total leaf area and growth traits (height, stem dry weight, foliage dry weight and total dry weight). The study indicated that variation in leaf area among the families was one reason for the lack of a strong relationship between P(N) and growth. 相似文献
19.
《Southern Forests》2013,75(3):221-226
The experiment was conducted to ascertain narrow-sense heritability (h 2) and the family-within-provenance variation in shoot die-back, taproot length and root biomass of half-sib Pterocarpus angolensis families from Malawi, Namibia and Zambia. Provenances differed significantly in shoot die-back for both shoot die-back seasons. A within provenance family effect was not significant in the first shoot die-back season but was significant in the second shoot die-back season. An increase in proportion of seedlings dying back, to 91%, for a Malawi family was observed in the second shoot die-back season. Provenance and within provenance family effects may be due to latitudinal differences between the provenances. The h 2 of shoot die-back was 0.07 (SE = 0.07) in the first shoot die-back season and 0.42 (SE = 0.27) in the second shoot die-back season. Narrow-sense heritability for root biomass was 0.81 (SE = 0.45). The h 2 for the second die-back season and root biomass suggest the traits are heritable. Random selection of individual families for assessing shoot die-back is important since this trait is only restricted to seedlings and saplings and not mature trees. Within provenance family effects for root biomass were significant, indicating differences between families. Two families from the most northerly provenances of Phalombe and Skull Rock in Malawi were significantly different from other southern families. Non-significant phenotypic correlation between shoot die-back and root biomass shows that shoot die-back is not likely to be determined by root size nor taproot depth. Although a non-significant negative phenotypic correlation (–0.15) between the second shoot die-back season and root biomass was obtained, a family from Malawi that had the highest mean shoot die-back in the second shoot die-back season had the smallest root biomass. Half-sib families with post shoot die-back growth potential, in the first shoot die-back season, are likely to have a better chance of post shoot die-back growth later. 相似文献
20.
在福建省洋口国有林场,对来自安徽省南部黄山地区的53个枫香家系进行子代测定,研究家系的遗传变异规律,开展优良家系及单株选择.结果表明:子代试验林14年生时,树高、胸径和单株材积平均值分别为8.05m、6.30cm和0.014 93 m3,生长性状的家系遗传力为0.437～0.576,受中强度的遗传控制,单株遗传力为D.113～0.195,受较弱的遗传控制;木材材性的家系遗传力为0.507～ 0.591,单株遗传力为0.360～0.500,均受中强度的遗传控制.以生长量为主要指标,选出速生优良家系9个,其树高、胸径和单株材积平均值分别为8.85 m、7.22 cm和0.021 49 m3,遗传增益分别为2.86％、5.47％和13.4％;从木材基本密度大于0.500 g·m-3的家系中选出7个生长材性兼优家系,树高、胸径、单株材积和木材基本密度的平均值分别为8.34m、6.79 cm、0.018 58 m3和0.518 g·m-3.所选出的速生优良家系和生长材性兼优家系可作为枫香育种材料在生产上推广应用. 相似文献