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无刺枸骨具有较高的生态和观赏价值.笔者以带芽新梢茎段为外植体,研究了培养基配方、培养方式以及移栽和扦插基质等对其组培快繁的影响.结果表明:无刺枸骨芽诱导和增殖的最佳培养基为MS(或B5)+BA3.0 mg/L+IBA0.1 mg/L(或NAA0.1 mg/L)+3.0%蔗糖+0.7%琼脂;生根培养则以试管外扦插生根为好... 相似文献
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The frequency of open-pollinated male-sterile seedlings from a male-sterile mother tree in Cryptomeria japonica D. Don was determined in 765 open-pollinated seedlings. Pollen was not formed by 29 out of the 765 seedlings. To find pollen donor candidates for 29 male-sterile seedlings, a male-sterile tree was crossed with five individuals in the neighborhood of the mother tree. Analysis of microspores in male flowers of F1 seedlings revealed that one of the five individuals had a heterozygous male-sterility gene. Paternity tests were conducted on the 29 male-sterile seedlings using eight kinds of CAPS markers in C. japonica. The pollen parents of 29 male-sterile seedlings were not only a tree in the neighborhood of the mother tree, but also other trees. Since it was found that the pollen parents of four of the male-sterile seedlings were not in the study plot, it was inferred that C. japonica trees that possess the male-sterility gene grow in other places and may be widely distributed. 相似文献
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Ten-year height data from three open-pollinated lodgepole pine progeny test trials were analysed in order to select individuals
for seed orchard establishment in the low and high elevation seed-planning units (TOLO and TOHI) of the new Thompson Okanagan
seed planning-zone in interior British Columbia, Canada. The total test population had about 35,000 individuals from 362 families
of 9 provenances and was divided into two portions, each serving as the base population for its appropriate seed-planning
unit. For each population, various genetic parameters were estimated and individual breeding values were predicted. Combined-site
estimates of individual, family, and within-family heritability ranged from 0.23 to 0.38, 0.77 to 0.84, and 0.17 to 0.29,
respectively. Estimated coefficients of type-b genetic correlation were greater than 0.81, indicating little G × E interaction
in this region. Provenance effects were large. Larch Hills and Inonoaklin River were the two superior provenances with an
expected gain of 13% and 10% in stem volume at rotation age of 60 years in TOLO. Individual breeding values was not uniformly
distributed among provenances and the top 100 individuals originated from 20 families in TOLO and 32 families in TOHI. Co-ancestry
among these individuals should not be a serious concern in seed orchard establishment as the predicted genetic loss due to
excessive inbreeding is only 1.06% in TOLO and 0.6% in TOHI. The status numbers of the two prospective seed orchards are 32
and 44, respectively, and both are well above the required minimum of 10 in British Columbia. Using unrelated clones for seed
orchard establishment may result in reduced optimum genetic gain and thus is not a favourable option. 相似文献