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1.
在砂仁由北纬24°37′(长泰)北移到北纬26°34′(南平)获得引种成功的基础上,通过进一步研究试验,在杉木林地套种砂仁,采取田间管理等技术措施的研究,以求达到提高果实产量的目的。  相似文献   

2.
桉树耐寒品种选育的重要性可行性   总被引:9,自引:0,他引:9  
桉树现已分布在我国17个省(区)(含台湾)600多个县。人工林面积已发展到90万hm~2,且每年约以5万hm~2的速度扩展。在我国桉树垂直分布从海拔4.5m的上海至2300m的云贵高原;水平分布以北纬23°为中心,南到北纬18°20′(海南三亚市),北到甘肃文县(北纬  相似文献   

3.
一、油橄榄引种情况 璧山县位于东径106°02′——106°20′,北纬29°17′——29°53′。海拔高一般为500—800m,最高海拔885m。气候属温暖湿润的亚热带气候。 1972年开始引种油橄榄60株,其中佛奥(Frantioi)58株,卡林(Kalinjoti)2株。1974年扦插成功,生根率达90%以上,现保存5万余株。  相似文献   

4.
1 自然概况神池县地处东经 111°4 2′~ 112°18′,北纬 38°5 6′~39°2 4′之间 ,位于黄河流域上中游、晋西北黄土丘陵沟壑风沙区 ,属亚寒半干旱大陆性季风气候。全县土地面积 14 .6 7万 hm2 ,其中山地占 30 %、丘陵地占 5 8%、平川地占 12 %。全县平均海拔为1782 m,最高海拔 2 5 45 m,最低海拔 12 80 m;年平均气温 4 .7℃ ,波动在 3.8℃~ 5 .4℃之间。极端最低气温 -33.8℃ ,最高温 34.8℃。 1月份平均气温 - 12 .7℃ ,7月份平均气温 19.5℃ ;年日照时数 2 816 .7小时 ;太阳辐射量 14 4 .0 3千卡 / cm2 ;无霜期 114天左右 ,最短 90天…  相似文献   

5.
藁城市位于华北平原腹地 ,省会石家庄东侧 30km处 ,地理坐标为北纬 37°5 1′~ 38°19′ ,东经 114°39′~ 114°5 9′ ,年平均气温 12 .5℃ ,无霜期 189d ,平均降水量4 98mm。全市东西横距 2 6km ,南北纵向 5 1km ,总面积836km2 。全市 14个乡镇 ,1个经济技术开发区 ,2 4 0个行政村 ,总人口 73万 ,耕地面积 5 .5万hm2 ,基本农田面积4 .3万hm2 。全市四旁植树统计数据为 90 0万株 ,其中农田林网约占 35 %左右 ,约 32 0万株 ,农田林网折合占地面积约 2 0 0 0hm2 ,保护农田面积 5 .3万hm2 ,林网控制率95 %以上。平原绿化尤其是农田林网化在…  相似文献   

6.
<正> 白蜡虫(Ericerus pela Chavannes)是我国特有的一种林业资源昆虫,种群繁衍中心在北纬27°左右,≥10℃的年积温为1,600-3,400℃的温带,长期生活分布范围约在北纬26°26′-32°54′的滇、黔、川三省交界的狭窄山原地带。经过多年引种试验,白蜡虫种群逐渐扩展到≥10℃的年积温4,500-5,000℃的北亚热带,在川、陕、湘、鄂等省形成了新的种虫繁殖基地。为了开发利用南亚热带的广阔山地资源,本试验特将白蜡虫引种至北纬24°28′,≥10℃的年积温为6,085.6℃的景东进行试验,经过七个世代的生物学特性观察,种群繁衍成效与白蜡的质量指标,均已达到部  相似文献   

7.
我国引种松树已达300余个种,育苗造林有211种。种植桉树的有15个省、区(包括台湾)。从南(海南岛北纬18°20’)至北(陕西汉中阳平关33°10’);从东(台湾北纬22°)至西(四川川北32°26’)的广宽土  相似文献   

8.
玉兰属5树种生理指标的对比研究   总被引:20,自引:1,他引:20  
对玉兰属 (Yulania) 5树种 ,即望春玉兰 [Y .biondii (Pamp .)D .L.Fu]、紫玉兰 [Y.liliiflora (Desr.)D .L .Fu]、玉兰 [Y.denudata (Desr.)D .L.Fu]、腋花玉兰 [Y .axilliflora (T .B .Zhaoetal.)D .L .Fu]和舞钢玉兰 [Y .wugangensis (T .B .Zhaoetal.)D .L .Fu]的生理指标作了测定 ,结果表明 ,5树种光合曲线较为相似 ,其光补偿点约 1 0 .0 μmol·m- 2 s- 1 ,饱和光合有效辐射约 1 0 0 0 μmol·m- 2 s- 1 ,光呼吸平均为 2 .1 μmol·m- 2s- 1 。 5树种光合曲线的差异主要体现在最大光合速率pmax这一指标上 ,分别为 :望春玉兰 8.2 μmol·m- 2 s- 1 、紫玉兰 8.0 μmol·m- 2 s- 1 、玉兰 1 4.4μmol·m- 2 s- 1 、腋花玉兰 1 1 μmol·m- 2 s- 1 、舞钢玉兰 1 5 .3 μmol·m- 2 s- 1 。 5树种的CO2 补偿点分别为 :望春玉兰 1 2 7μmol·mol- 1 、紫玉兰 62 μmol·mol- 1 、玉兰 5 2 μmol·mol- 1 、腋花玉兰 1 0 6μmol·mol- 1 、舞钢玉兰 5 1 μmol·mol- 1 。叶片水分利用效率分别为 :望春玉兰 0 1 4%、紫玉兰 0 2 9%、玉兰 0 1 6%、腋花玉兰 0 2 0 %、舞钢玉兰 0 2 4% [molCO2 ·(molH2 O) - 1 ]。望春玉兰是辛夷的主要原植物 ,其水分利用效率较小、CO2 补偿点高 ,因此 ,丰产栽培时 ,要  相似文献   

9.
1 沙棘分布及适生范围  沙棘 (HippophaerhamnoidesL .)属胡颓子科沙棘属落叶灌木或小乔木 ,别名酸刺、醋柳、黑刺等。广泛分布在欧亚大陆的温带和寒温带地区 ,跨东经 2~ 12 3° ,北纬 2 7~ 69°之间 ,垂直分布海拔 0~ 52 0 0m。沙棘资源在中国分布东经 75°32′~ 12 1°4 5′ ,北纬2 7°4 4′~ 4 8°35′之间 ,包括辽宁、河北、山西、陕西、甘肃、青海、四川、云南、内蒙、宁夏、新疆等省区。俄罗斯沙棘栽培品种分布于北纬 50°以北 ,近年来辽宁、黑龙江、内蒙、甘肃等省引种栽培。沙棘以其独特的生态效益 ,…  相似文献   

10.
兰考泡桐(Paulownia elongata S.Y.Hu)是我国优良速生用材树种之一。从1963年起引种到甘肃,迄止1988年,栽培面积已达106万亩,栽植株数3178万株,保存1722万株,活立木总蓄积量达188.8万立方米。实践证明,兰考泡桐的引种是成功的。一、引种区自然概况兰考泡桐在甘肃引种栽培范围为北纬32°30′—36°40′,东经103°20′—108°38′之间;  相似文献   

11.
Reproductive phenology of multiple use native plant Calo- phyllum inophyllum L. was studied in Yeppoon (23°7’60″ S, 150°43’60″ E), northern Australia (southern hemisphere) and in Meegoda (6o18′51″N, 80o31′3″E), Sri Lanka (northern hemisphere). C. inophyllum trees in Yeppoon, Australia had relatively shorter flowering periods, shorter floral life spans, longer fruit life spans, smaller flowers and larger fruits compared to those in Meegoda, Sri Lanka. Although the number of flower buds/ inflorescence was comparatively higher in Meegoda, C. inophyllum trees in both locations had similar mean number of mature fruits/ cluster due to the higher floral abscission in C. inophyllum trees at Meegoda. Despite having a comparatively lower fruit yield (664 000 fruts·ha 1·a 1), C. inophyllum trees in Yeppoon had higher kernel weights (2 988.0±853.2 kg·ha -1 ·a -1 ) and oil yields (1 332.6±380.5 kg·ha - 1 ·a -1 ) compared to those in Meegoda.  相似文献   

12.
A field experiment was conducted from 1984 to 1994 in the North of Paraná State, Brazil (23°45′ S, 52°30′ W), to evaluate the effect of Grevillea robusta (grevillea) on interplanted coffee. Grevillea was planted in five densities (26, 34, 48, 71, and 119 trees per ha). Compared with open grown coffee, there was no decline in the yield of coffee under grevillea at densities of 26, 34, and 48 trees per ha; however, total economic productivity (including the value of both coffee and grevillea) was higher for combinations of coffee and grevillea at 34, 48, and 71 trees per ha. The severe radiative frost of June 1994 that damaged most coffee plants did not damage coffee plants interplanted under grevillea trees at densities of 71 and 119 trees per hectare. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

13.
The present study was carried out to evaluate variability in fruit characteristics and nutritional quality of Baobab fruits with the aim of providing the background to select trees bearing fruit with desirable characteristics for further utilisation. Vitamin C, total sugar and ash contents were assessed in 178 Baobab fruit samples from 11 sites in Burkina Faso, Mali and Niger. Furthermore the following tree and fruit physical characteristics were recorded: tree height, bark colour, fruit size, pulp weight, seed weight, seed size and pulp colour. The content (mean?±?SD) of vitamin C was 4.78?±?1.02?g?kg?1, sugar 514?±?72?g?kg?1 and fruit weight 293?±?96?g. There was a significant correlation between annual precipitation of the tree population site and vitamin C content but not with sugar content. For sugar, there were significant positive correlations with latitude and longitude. Negative correlations were found between fruit size and both longitude and latitude with smaller fruits generally being found to the north/east. No relation was found between pulp or bark colour and the sugar or vitamin C content. The contents of protein, lipid, carbohydrates, ash and moisture in the seeds ranged from 156 to 159, 143 to 150, 641 to 652, 44 to 49 and 50 to 55.7?g?kg?1 respectively. The variation for vitamin C and sugar found within populations is a first indication that valuable gains could be made by selection of superior trees.  相似文献   

14.
正杜仲(Eucommia ulmoides Oliv)属杜仲科(Eucommiaceae),本科仅1属1种,是仅存于我国的第三纪孑遗植物,名贵经济树种,国家二级保护树种[1,-2]。杜仲叶、雄花、果皮和杜仲皮都含有多种具有独特的医疗保健功能的活性物质[2-3]。例如  相似文献   

15.
The fruit of Vitellaria paradoxa is an ideal raw material in cosmetic, pharmaceutical and confectionery industries. There are no accurate data on annual fruit yield due to the lack of objective assessment tools. The objectives of this study were to develop fruit yield prediction models based on dendrometric and fruiting variables, to examine variations in these variables between upland and lowland populations in Burkina Faso, and associations between these variables. A total of 191 fruiting trees were selected according to crown accessibility, and 17 dendrometric and fruiting variables were recorded. The fruit yield, expressed in number of fruits per tree, fresh and dry weights of fruits, was assessed by collecting fruits dropped overnight until the end of the fruiting period. Fruit yield prediction models were derived for each population using partial least squares regression. The results showed significant differences in dendrometric and fruiting variables between populations (P < 0.01). The lowland population had the highest values for most of the dendrometric variables while fruiting variables were the highest for the upland population. A strong significant correlation (P < 0.01) was found between number of shoots and fruiting variables. Within individual trees, fruit yield was lowest for the bottom part of the crown and the section of the crown with north-east orientation. Fruit yield parameters were successfully predicted based on selected dendrometric and fruiting variables (prediction error = 0.092 and 0.125 for upland and lowland populations, respectively). All fruiting variables, number of shoots and crown attributes had the highest influence on the models.  相似文献   

16.
于2001~2003年在东陇海地区的邳州市进行了金太阳杏和凯特杏日光温室栽培试验,结果表明:凯特杏比金太阳杏树势旺,成花少,单株产量低,成熟期比金太阳杏晚,但果实比较大,平均单果重110 g,而金太阳杏只有60 g左右。栽后第2 a(2002年),金太阳杏5月1日成熟,有40%左右的植株结果,平均产量0.29 kg/m2;凯特杏5月11日成熟,有35%左右的植株结果,平均产量183.2 kg/666.7 m2。栽后第3 a(2003年),2品种所有植株全部结果:金太阳杏4月26日成熟,产量1.48 kg/m2;凯特杏5月3日成熟,产量1.40 kg/m2。日光温室杏栽培经济效益高,栽后第2 a获得产值3.00元/m2,栽后第3 a产值高达14.43元/m2。  相似文献   

17.
为寻找影响板栗产量的主要因子,作者用数理统计的方法,通过对江苏省新沂市沭河果园4种不同密度8a生板栗密植园单株产量及与其相关产量构成因子的简单相关分析和逐步回归分析,得到了包括结果母枝数、主干截面积、结果母枝抽生结果枝数和单粒重在内的最优多元线性回归方程;再对人选的4个主要性状进行通径分析,明确了在保证树干一定粗度生长的条件下,保留适宜的结果母枝数,促进母枝抽生结果枝,是板栗丰产栽培的关键技术措施  相似文献   

18.
野鸦椿主要经济性状遗传参数估算及优良家系选择   总被引:1,自引:0,他引:1  
野鸦椿(Euscaphis japonica)12个表型优良单株的半同胞子代测定结果表明:野鸦椿表型优良单株的半同胞子代家系间在单位面积果实产量、果穗长度、穗重、单穗果数等方面存在着显著或极显著差异;果穗长度、穗重、单穗果数、单位面积果实产量4个性状家系遗传力和单株遗传力都较高,性状间有明显的线性相关。通过方差分析、相关分析和聚类分析等方法,对各初选植株半同胞子代家系间的单位面积果实产量、果穗长度、穗重以及单穗果数分析比较,从初选的12个家系中进一步选择出经济性状表现优良的N1、N2、N5、N6、S1、S2、S3等7个优良家系。  相似文献   

19.
为了探寻能促进云南三台核桃中幼树生长结实的技术措施,从而为云南核桃的提质增效提供理论依据,以树龄为10~15 a的三台核桃中幼树为研究对象,采用修剪、螺旋环剥、花前灌水这3种技术处理进行了为期2年的试验研究,调查和综合比较分析了不同处理的新梢发枝力、果枝率、新梢生长量、单株产量。结果表明:螺旋环剥处理,能增加母枝抽发的新梢数量,但对新梢的营养生长却有一定的抑制作用,能使其果枝率和单株产量均有提高,其平均单株结果数可达508.3个,增产效果明显;修剪处理,增强了中幼树的发枝力,增加了母枝抽发的新梢数量,增产效果也较明显;花前灌水处理,促进了新梢的长度生长和粗度生长,促进了其营养生长,对其果枝率和单株结果数均一定的促进作用,但增产效果不很显著。  相似文献   

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