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通过对华北落叶松种子园多年的调查,分别筛选出10个高产无性系和10个低产无性系,并初步测定了高产无性系与低产无性系的种子产量、品质、苗期生长表现。结果表明:高产无性系单株种子产量为0.17kg,显著高于低产无性系(0.016kg),但两类无性系在种子品质和苗期生长表现均无显著差异。说明高产无性系虽然产量高,消耗的营养多,但并不影响种子的优良品质,如在分类经营的情况下,可为种子园疏伐和进一步改良提供理论依据。 相似文献
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杉木种源种子园种子产量和质量分析 总被引：1，自引：0，他引：1
1988年在吉安市青原区白云山林场营建的我国第一个杉木种源种子园(面积15hm^2)于1990年开始投产后。每年所产的种子都用于江西及其它省区重点工程造林,产生了较大的经济和社会效益。由于本种子园在营建之初就考虑了影响种子园种子产量和质量的诸多因素．与现有其它杉木种子园相比,在种子产量和质量方面都有较大程度的提高：1990-1997年,平均年产种量为39．45kg／hm^2,平均发芽率达52．05％,最高达78％,远高于我国杉木一级种子发芽率的标准(45％)。杉木种子如此高的发芽率尚未见诸报道。 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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杉木第二代种子园无性系产量选择的研究 总被引：6，自引：1，他引：5
对三明市郊国有林场杉木第二代种子园无性系产量测定,应用生产力指数的丰产性评价(PQI)和产量因子的聚类分析,115个无性系划分为4类:高产、中产、低产、极低产,其中高产无性系19个,产量占总产量的39-71%,并着重进行高产无性系的播种品质检验,初步评选出16个产量高、种子品质较好的无性系。 相似文献
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无性系、立地、郁闭度对杉木种子园产量和质量的影响 总被引：1，自引：0，他引：1
分析了无性系、立地、林分郁闭度等因子对杉木种子园产量和质量的影响，结果表明：无性系、坡向、郁闭度对杉木种子园产量有显著影响，对种子质量也有影响。杉木种子园宜选择阳坡、半阳坡，采用优质高产无性系建园；抓好密度和郁闭度管理，林分郁闭度以小于0.6为宜。 相似文献
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马尾松一代无性系种子园营建与丰产技术研究 总被引：12，自引：0，他引：12
本研究历经“六五”选优,“七五”建园与“八五”投产,长达工5年之久的科学研究与生产实践,比较系统地阐述了马尾松一代无性系种子园的营建、管理与种子丰产技术。“八五”期间种子园开始生产种子,产量逐年上升,1995年大面积平均每公顷产量为9.375kg,最高小区平均每公顷产量达27.825kg,属于马尾松投产初期高产种子园之列。种子园混系种子质量优异,5年生子代林材积增益比对照大41.4％。种子园的建成与投产,可为速丰林建设提供优质良种。 相似文献
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<正> 种子园能提供遗传品质得到一定程度改良的种子。据子代测定结果表明,现阶段杉木种子园遗传增益达15%左右。目前人们已认识到采用种子园良种,是促进杉木速生丰产重要措施。因此,促进种子生产达到高产、稳定是当前杉木种子园经营管理急待解决的问题。本场为我省林木良种繁育重点基地之一。 相似文献
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J. H. Heering 《Agroforestry Systems》1995,30(3):341-350
The forage, wood and seed production of sixSesbania sesban accessions was assessed under irrigated conditions for two cutting frequencies and heights. Control trees were left uncut to measure their seed production potential. The trial was conducted over an 18-month period. The fastest growing accession produced almost 10 t/ha total dry matter (DM) after six months of growth, 40% of it being leaves. Total DM yield was higher at the six-month cutting interval compared to the three months' interval with yields between 25–42 t/ha/year. Some accessions could not sustain their high level of production but showed drastic drops in yield after repeated cutting. In general leaf DM production increased with increased cutting height. When cut at 150 cm the DM leaf yield at the three-month cutting interval ranged form 9.7–18.2 t/ha. More plants survived at the three-month cutting frequency. Seed yields varied considerably between accessions (0.02–1.56 t/ha at the six months' interval). After 18 months of undisturbed growth the trees yielded 36.5–83.7 t/ha total DM comprising 21% leaves. Fresh wood biomass ranged between 56.4–138.0 t/ha and seed yields 2.7–6.6 t/ha. 相似文献
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杉木种子园高产稳产的研究 总被引：11，自引：0，他引：11
根据全国7省26个杉木种子园有关数据,及浙江杉木种子园高产稳产研究协作组的研究报告,从高产稳产角度,对园址选择、建园材料选择、定砧密度、结实前管理及结实后管理技术进行探讨。园址最好选在撒粉期雨量不过多、不常遭冻害的杉木一般产区;选取低山向阳缓坡、隔离条件好、土壤深厚而肥力中等、湿润而排水良好的地方建园。建园材料选遗传增益高而结实中等以上无性系,注意花期相配。定砧密度要适当。结实前狠抓嫁接株保存率及直冠率,通过土壤管理及适当疏枝培养宽大、透光树冠;结实后狠抓土壤管理、花粉管理、及时疏伐及病虫防治,结实衰退时及时更新改造。 相似文献
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Charles F. Yamoah Professor of Plant Sciences James R. Burleigh 《Agroforestry Systems》1990,10(2):169-181
Food production in the densely populated Rwandan highlands is impeded by soil erosion and loss in fertility. Alley cropping
leguminous shrubs with food crops on contours is purported to minimize the problem and to provide wood and forage. This study
reports the effect of Sesbania prunings plus moderate levels of N and P on bean (Phaseolus sp) and maize (Zea mays) yields in alley cropping. Experimental design was a randomized complete block with split-split plots. Main plots were alley
width: 2, 4, 6 and 8 m. Phosphorus (P) at 0, 30 and 60 kg P2O5/ha occupied the subplot and nitrogen (N) at 0, 30 and 60 kg/ha were assigned at the sub-sub plot level. No P was applied
to maize during the second cropping season. Crop yield in kg/ha included the land space taken by hedgerows. Bean yield in
6 m alleys (1100 kg/ha) was about twice that in 2 m alleys (500 kg/ha). Bean responded to N and P. Optimum alley width and
N for bean yield were 6 m and 30 kg/ha, respectively. Cuttings from alley hedgerows provided stakes for climbing beans. Maize
responded to N but not to residual P. The highest maize yield came from 8 m alleys with 40 kg/ha, but yields from 8 and 6
m alleys with the same N treatment were not significantly different. Maize plants in middle rows were significantly taller
than plants in rows adjacent to hedgerows. Maize rust development showed significant alley width and row position effect.
There were significantly fewer uredinia in the Sebania alleys relative to the control plots without shrub hedgerows. Rust development on maize in middle rows was significantly
greater than development in border rows. 相似文献
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云雄是云南省林业科学院经济林研究所历时20多年选育出的板栗新品种,通过优株选择、无性系评比试验、物候观测、授粉试验、花粉生活力测定、区域化栽培试验、产量和品质测定等多年的栽培研究.结果表明,该品种坚果大、品质优、产量高.用其授粉,平均成实率高达87.4％,且对主栽品种坚果增重明显,增重幅度为4.9％～26.3％.用云雄花粉人工辅助授粉,较自然授粉平均每公顷增产396.5 kg,增产率18.5％;坚果平均增重1.43 g,增长率16.4％.因此,在板栗栽培中,选用云雄作为授粉品种,对提高产量和品质具有重要作用. 相似文献
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2008年春天我国南方发生的严重雨雪冰冻天气对毛竹林造成严重危害,作者调查了富阳区毛竹林的受灾特征及其影响因子,并在此基础上研究了不同施肥处理对受灾毛竹林恢复生长的影响。结果表明：1）毛竹林受灾程度与其所处的海拔、坡向、坡度、坡位、竹林地土壤厚度等环境因子以及毛竹林林分结构密切相关,其中海拔高度的影响最为显著;2）不同施肥处理对毛竹林恢复生长的影响差异显著,在试验的几个处理中,以在高海拔（500 m）区使用大剂量施肥（生物肥料160 kg/667 m2和复合肥40 kg/667 m2）和在低海拔（300 m）区使用小剂量施肥（生物肥料100 kg/667 m2和复合肥20 kg/667 m2）的新竹产量为高,每年产量分别达到2 243.3 kg/667 m2和2 258.3 kg/667 m2,分别比对照增加65.4%和63.3%;3）高海拔地区的毛竹林因受损严重,在适当施肥后其新竹萌发量比低海拔地区的要高,但立竹直径明显低于低海拔地区。 相似文献
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云雄是云南省林业科学院经济林研究所历时20多年选育出的板栗新品种,通过优株选择、无性系评比试验、物候观测、授粉试验、花粉生活力测定、区域化栽培试验、产量和品质测定等多年的栽培研究。结果表明,该品种坚果大、品质优、产量高。用其授粉,平均成实率高达87.4%,且对主栽品种坚果增重明显,增重幅度为4.9%～26.3%。用云雄花粉人工辅助授粉,较自然授粉平均每公顷增产396.5 kg,增产率18.5%;坚果平均增重1.43 g,增长率16.4%。因此,在板栗栽培中,选用云雄作为授粉品种,对提高产量和品质具有重要作用。 相似文献
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《Scandinavian Journal of Forest Research》2012,27(1-4):309-315
Isozyme‐analysis techniques have been applied to test the efficiency of supplemental mass pollination in a seed orchard of Pinus Sylvestris. Mass pollination was done on one single occasion before the general pollen dispersal. The results of isozyme analyses of seed after mass pollination demonstrate that it is possible to introduce desirable genes into the seed orchard crop. Mass pollination without isolation of female strobili gave an average contribution of 4% to the total fertilizations and after isolation of female strobili 26.5%. The main conclusion is that supplemental mass pollination offers very interesting possibilities for breeding, particularly if some kind of isolation of the female flowers is made. It can increase the seed quality as well as improve the breeding value of the seed orchard. More attention should be paid to increasing the efficiency of the controlled pollination. It is suggested that in the future, more effort is invested in improving the technique of mass pollination. 相似文献