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杉木优良杂交组合筛选及配合力分析 总被引:10,自引:0,他引:10
浙江省三批杉木双亲本子代测定林,交配设计为分组不连续的半双列杂交,共149个组合。方差分析和配合力显著性测定结果表明:组合间树高、胸径、材积生长差异显著或极显著,这种差异主要由一般配合力(gca)即基因加性效应引起,基因非加性效应也起一定作用;组合间木材密度性状也存在显著差异,但主要由特殊配合力(sca)即基因非加性效应决定。筛选出25个优良杂交组合,4~6年生树高、胸径、材积的遗传增益分别达7.0~21.1%、12.3~30.2%、28.4~54.2%。 相似文献
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杉木种子园早期高产关键技术研究 总被引:3,自引:1,他引:2
经近10年的试验研究表明:1.选择早实高产无性系,增加它在种子园的无性系比例。2.提高正冠率,加强早期密度。3.建立花粉收集区,做好人工辅助授粉。以上三点是关键,由此在丰产区12年生杉木种子园亩产种子11.10kg,7年生为亩产7.38kg。 相似文献
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对杉木种源两次全分布区试验的13、16、18、28年生试验林的生长、材性测定资料进行了研究,结果表明:杉木种源间的树高、胸径、材积、木材比重、形数等性状都存在着丰富的遗传变异,其种源的遗传力在中等以上;以速生优质为目标作综合指数选择,从57个参试种源中,评选出福建崇安、建瓯、浦城、贵州锦屏、广西融水、福建武平、南平7个优良种源,其中广西融水、贵州锦屏、福建南平为稳定性好种源,在13年生时其材积遗传增益为417%~823%,在28年生时,其树高、胸径、材积现实增益分别为77%~156%、99%~309%、308%~911%;生长性状与木材比重无显著的表型相关,但两者遗传相关呈负向,随林龄增加达到高度负相关,生长性状的改良有降低木材比重的趋势;广西融水、贵州锦屏等优良种源早期就表现出速生性,而福建崇安、浦城、建瓯等武夷山闽西北山地种源,前期速生性并不十分显著,随林龄增大,其生长速率加快,直径生长尤为突出,具有巨大的生产潜力,更适合在浙江省推广应用。杉木种源研究应延续到半个轮伐期以上。 相似文献
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In order to explore the salt tolerance mechanism of Machilus thunbergii, the effects of salt stress on seedling biomass, root morphology, sodium and potassium absorption and distribution were studied. The results showed that the above-ground biomass increased slightly under lower salt stress conditions, while the below-ground biomass, root length and root surface area showed a downtrend. The above-ground growth was limited under high concentration salt stress, while the under-ground growth was not subject to significant restrictions. The absorption of Na+ in root increased under salt stress, but that of K+ decreased. The ability of Na+ transporting from root to leaf and stem was weakened. The accumulation of Na+ in stem and leaves was less. With the decreased absorption of K+, the ratio of Na+/K+ also continuously increased. With the increased concentration of salt stress, the ability of K+ absorption in roots increased. The ability of K+ transporting from root to leaf and stem was enhanced, which resulted in significant increase of K+ in the leaves and stem. The accumulation of Na+ in the under-ground was significantly greater than that in above-ground, while the K+ content in above-ground increased significantly, which played a key role in maintaining normal growth and metabolism of M. thunbergii. 相似文献
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<正>2010年10月16日,云南省师宗县竹基乡界桥村张某家一头水牛行动不利,站立时后驱会有向下倾倒的姿势。1主诉近一月来秋收特别忙碌,加之阴雨连绵, 相似文献
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