Page 129 - 《广西植物》2023年第7期
P. 129
7 期 张学峰等: 遗传改良对杉木针叶和种实性状的影响 1 2 9 7
Abstract: To reveal the effects of genetic improvement on leaf and seed traits of major afforestation timber speciesꎬ and
to clarify the variation trend of traitsꎬ selected trees (improved population) of the fourth cycle of Chinese fir breeding
and phenotypic superior trees and ancient trees (unimproved population) in four provinces and five regions were selected
as the research objects. The needle and cone traits of 218 clones were investigatedꎬ and the study used variance analysis
and multiple comparison methods to study the phenotypic differences of genetic improvement on Chinese fir and different
types of Chinese fir. The correlation analysis was used to explored the effect of genetic improvement on the phenotypic
traits of Chinese fir needles and conesꎻ the principal component analysis and cluster analysis were used for
classification. The results were as follows: (1) The needle lengthꎬ needle width and seeding rate of the unimproved
population were 13.28%ꎬ 10.81% and 33.90% lower than those of the improved populationꎬ respectively. Other traits
showed that the unimproved population was higher than the improved populationꎬ with differences ranging from 10.90%
to 27.03%. The coefficients of variation of cone lengthꎬ cone width and seeding rate of the unimproved population were
9.14%ꎬ 12.73% and 15.38% higher than those of the improved populationꎬ respectively. (2) Among the four traits of
cone lengthꎬ cone widthꎬ bract scale length and bract scale widthꎬ only cone length and cone width (0.931)ꎬ bract scale
length and bract scale width (0.622) were extremely significant positive correlation between them in the unimproved
population. After genetic improvementꎬ the four traits showed a significant or extremely significant positive correlation in
pairs. (3) Cone length and cone width in Sichuan Ya’an (SCYA) were 48.83% and 53.26% higher than those in the
improved populationꎬ and the hundred ̄grain weight in Anhui Huangshan (AHHS) was 16.92% higher than those in the
improved population. (4) Genetic improvement led to a decrease in the proportion of Chinese fir with loose ̄stretched
conesꎬ and an increase in the proportion of Chinese fir with tightly packed and inverted cones. In summanyꎬ this study
believes that the genetic improvement of Chinese fir leads to the reduction of cone sizeꎬ changes the proportion of
different needles and cone typesꎬ and changes the correlation between needle traits and cone traitsꎬ which will be helpful
for providing the basis to the evaluation of Chinese fir germplasm resources and future multi ̄targets breeding.
Key words: Cunninghamia lanceolata (Chinese fir)ꎬ genetic improvementꎬ breeding populationꎬ needleꎬ cone
对目标性状的遗传改良会使其他性状产生反 种目标之一ꎬ在主要造林用材树种的遗传改良中ꎬ
应ꎬ其本质是性状间的遗传相关ꎬ即同一个基因位 生长性状往往是首选改良性状ꎮ 但是ꎬ在对生长
点影响多个性状的表达ꎮ 在作物中ꎬ株高是株型 的持续遗传改良中ꎬ有研究发现其会对其他性状
的重要影响因素之一ꎬ对作物产量等其他农艺性 有直接或者间接的影响ꎮ 一方面ꎬ生长与材性性
状有着直接或者间接的影响ꎮ 在玉米的株高相关 状存在负的遗传相关ꎬ即随着生长性状遗传增益
基因中ꎬ马雅杰等(2022) 鉴定出多个主效单核苷 的不断增加ꎬ木材密度等材性性状有下降的趋势
酸多态性( single nucleotide polymorphismsꎬSNP) 位 (黄寿先等ꎬ2004)ꎻ另一方面ꎬ生长量的持续增加
点ꎬ筛选出的候选基因主要参与激素合成与信号 也导致开花结实等繁殖能力性状的下降( Wu et
转导、糖类代谢、细胞分裂调控等途径ꎬ其中有些 al.ꎬ 2021)ꎮ
基因可同时调控株高、穗位高和穗位系数ꎬ与产量 杉木(Cunninghamia lanceolata) 是我国南方重
性状显著相关ꎻ目前已经命名的 25 个小麦矮杆基 要的造林用材树种之一ꎬ根据第九次全国森林资
因ꎬ张红杰(2021) 发现了 331 个数量性状基因座 源清查结果ꎬ全国杉木栽培面积达 990 万 hm ꎬ约
2
(quantitative trait locusꎬQTL)、270 个全基因组关联 占全国人工林面积的 20%ꎬ蓄积量达 7.55 亿 m ꎬ
3
研究(genome-wide association studiesꎬGWAS) 连锁 约占全国人工林蓄积量的 25%ꎮ 杉木自然类型多
位点和 83 个株高相关基因ꎬ确定了 66 个控制小麦 样ꎬ存在丰富的变异ꎬ且性状间存在一定的相关
株高的 QTL 簇ꎬ其中部分同时控制株高和粒长等 性ꎬ如灰色类树高增量比黄色类快 5%左右ꎬ而灰
性状ꎬ也存在部分仅控制株高ꎬ而不影响籽粒相关 色类平均单株材积比黄色类约低 10%( 叶培忠和
的性状ꎻ水稻株高的 qPH ̄IAA30 等相关基因ꎬ同时 陈岳武ꎬ1964)ꎮ 自 20 世纪 50 年代系统开展杉木
调控穗长、每穗颖花数、产量和千粒重( 唐嘉瓅ꎬ 遗传改良以来ꎬ生长性状始终是主要育种目标ꎬ经
2021)ꎮ 生长性状是林木尤其是用材林的主要育 过多个世代的选择ꎬ生长性状获得了显著的遗传