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无锡水蜜桃是无锡市的传统特产，它以果大、味甜、果肉柔软多汁、色泽艳丽而著称，在国内外市场享有一定的声誉。我场在１９９９年和１９９６年共拓植水蜜桃面积４hm２。１９９９年到２０００年共拓植水蜜桃面积６hm２。我场自确立了创名牌、创优质的新的生产和经营思想以来，强化了对桃园的养护管理，现已初见成效，经济效益大幅提高。一是高标准进行拓植。水蜜桃栽植时要开定植沟，一般沟宽８０cm，沟深６０cm，每亩（６６７m２）的定植沟内放稻草７５０kg进行沤制。３月中旬开始种植，种植前用１kg复合肥与土壤拌匀撒入栽植沟底，栽植密… 相似文献
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阿克苏市红枣栽植面积已达1.67万公顷,根据修剪需要划分为嫁接一年、嫁接二年及嫁接二年以上三类,栽植密度主要有:4米常规行距、4米常规行距中间加密临时行、2米高密行距等3种。现针对不同栽植密度和嫁接时间的枣树提出冬季修剪技术方案。1永久株的选留1.1永久株的选留条件 相似文献
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随着我省干果业的不断发展,在板栗基地建设中,有很大部分是先栽植实生苗,后嫁接（一般栽植的次年或第３年嫁接）板栗优良品种,以期达到高产、优质、高效的基地建设目的。板栗嫁接后当年（或次年前半年）的管理是确保嫁接成活的必要条件。其管理技术主要体现在以下５方面。抹砧板栗嫁接后,要设专人管护。嫁接后５－１０ｄ（天）,有的接穗芽已萌发或湿润呈嫩绿色,这表明已经成活,同时砧木上的隐芽也萌发了,这时要及时抹去（可带手套）砧木上萌发的芽,以便集中营养供接穗生长。以后每隔５ｄ（天）左右观察抹芽１次,直到接穗发芽、长… 相似文献
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垂榆是白榆(Ulmus pumila)的变种(Ulmus pumila var.pendulaRehd.),从新疆引种到内蒙古。由于垂榆在集通铁路沿线未有嫁接栽植,从1999年至2003年,在商都铁路苗圃进行了较系统的嫁接试验,并用该苗木在集通铁路沿线的锡林郭勒盟白旗和桑根达来地区进行了栽植试验,取得了具有实用价值的试验数据,为该地区栽植垂榆提供了宝贵的经验。 相似文献
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1 砧木的选择与处理
1．1砧木选择
幼树嫁接是对3～8年生，地径在3cm以上实生幼树进行嫁接。对于新栽植的幼树，要注意加强土、肥水管理，促使其生长旺盛，催生一年生旺枝，从而保证成活率，提早进行改良。 相似文献
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大扁杏耐旱、抗寒，适应性强、经济效益高。发展大扁杏，主要采用植苗方法建园。用嫁接苗建园园貌整齐，便于管理和实行集约经营。目前效益好的杏扁园主要是植苗建的杏园。 1.植苗建园：先在苗圃内养好嫁接苗，用接好的苗木按规划栽植建园。栽植之前要搞好规划，安排好栽植小区、道路、防护林等，要平整土地，做好水土保持工程，肥培熟化树穴，搞好一系列栽植前的准备工作，栽植后要加强管理。 2.实生苗建园：在选定的园址上，经过规划、整地、肥培树穴后，先用山杏或土杏的实生苗栽植，成活后再嫁接成大扁杏。实生苗建园是干旱地区用嫁接… 相似文献
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Van Den Driessche R 《Tree physiology》1992,10(2):141-152
Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings of a single seed source were grown in a bare-root nursery for two years to produce five different stock types by varying spacing and transplanting treatments. They were then planted in the forest together with one-year-old container seedlings of the same seed source, which constituted a sixth treatment. Stem volume mean relative growth rate (R(v)) was low immediately after planting for all stock types except the container seedlings, and increased over the following 7.6 years. An 8-week greenhouse test of the six stock types showed that dry weight mean relative growth rate (R(w)) generally decreased with seedling dry weight, but this effect was less obvious after planting, because only the three smaller stock types showed a decrease in R(w) with size. In another experiment, bare-root Douglas-fir seedlings were grown at five different spacings in a nursery for two years, and seedlings from each spacing treatment were sorted into large or small by height. The resulting 10 treatments were planted in the forest and stem volumes determined over 6.7 years. The linear effect of nursery spacing on stem volume was no longer evident 3.6 years after planting, but large seedlings had greater stem volume than the small seedlings throughout the 6.7 years of the study. There was no indication that R(v) declined with time, but small seedlings had higher R(v) than large seedlings. Relative growth rates of two-year-old Douglas-fir were depressed for a year or two after planting, but then remained relatively constant, or increased during the ensuing 5 years. Relative growth rates of smaller seedlings were greater than those of larger seedlings so that relative biomass differences decreased with time, and the time advantage (the time necessary for small seedlings to reach the present biomass of large stock) of larger stock decreased. Absolute size differences increased with time. 相似文献
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Height and diameter increment and timber quality in Scots pine (Pinus sylvestris L.) planted as seedlings of different sizes were studied in two experiments. When compared 32–37 years after planting, seedlings that were smaller than neighbouring seedlings at the time of planting, had generally attained lower height and diameter, and had higher mortality compared to seedlings that were of equal size or larger than their neighbours. Tree size was strongly related to seedling size two years after planting. Trees originating from small seedlings had thinner annual rings and branches than trees originating from large seedlings. These characters are of importance for timber quality. It seems that the competitive ability of a tree is to a large extent established early in stand development. 相似文献
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Ozone exposure decreases belowground carbon allocation and root growth of plants; however, the extent to which these effects persist and the cumulative impact of ozone stress on plant growth are poorly understood. To evaluate the potential for plant compensation, we followed the progression of ozone effects, with particular emphasis on the development of new roots. Ponderosa pine (Pinus ponderosa Dougl. ex Laws.) seedlings were exposed to ozone for 2 years. Following removal of the seedlings from ozone, root growth was assessed to characterize the carry-over effects on new root production, and carbohydrate concentrations were measured to determine if allocation strategies differed among ozone treatments. Four months after removal from ozone, dormant seedlings had significantly lower starch concentrations in stems, coarse roots and fine roots than control seedlings. Following root flushing, starch concentrations in all seedlings decreased, with ozone-treated seedlings containing significantly less starch, sucrose, fructose, glucose and total monosaccharides than control seedlings. There was some evidence that stem starch was mobilized to compensate partially for the lower concentrations of root starch in ozone-treated seedlings; however, there was significantly less new root production in seedlings previously exposed to ozone for 2 years than in control seedlings. Early senescence of older needle age classes, perhaps resulting in inadequate available photosynthate, may be responsible for the reduction in new root production during the year following exposure to ozone. Stored carbohydrate reserves, which were depleted in seedlings previously exposed to ozone, were insufficient to compensate for the ozone-induced reduction in canopy photosynthate. We conclude that there are carry-over effects of ozone exposure on ponderosa pine seedlings, including an enhanced potential for seedling susceptibility to other stresses even in respite years when ozone concentrations are low. 相似文献
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新疆杨作为宁夏主要造林树种之一,具有较强的适应性和抗天牛特性,但采取常规扦插育(89.3%和67.6%)相比有较大差异,主要原因:一苗成活率较低,合格苗数量相对少,为了提高新疆杨育苗质量,采用了地膜覆盖扦插育苗试验。试是受2000年春苗价格过热的影响,致使种条质量低验结果表明:可提高苗木成活率21.7～25个百分点,1年生苗高比对照增加0.71～0.97m,2年生于1999年;二是2000年春季气温不稳定,5月上旬苗木合格率比对照提高16.2～17.5个百分点。至中旬连降两场中雪,地温回升缓慢,影响了插穗正 相似文献
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We examined the effects of fencing on deer browsing on seedlings 13 years after the building the experimental fence on Mt.
Ohdaigahara, central Japan, where the sika deer (Cervus nippon) population is high. There was no difference in the species number of seedlings between 1991 and 2004. The density of seedlings
in the fenced plot in 2004 was three times higher than in 1991. Although the unfenced plots had no seedlings higher than 20 cm,
there were seedlings up to 120 cm in the fenced plot. These results suggest that 13-year fencing promoted regeneration of
seedlings in this area. 相似文献
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To clarify the establishment pattern of Cryptomeria japonica seedlings, the demography of current-year seedlings was studied under various micro-environmental conditions for 2 years in a cool-temperate old-growth forest in the snowy region of Japan. In both years, more than 70% of seedlings that emerged died within a year, and differences in the survival rate of seedlings with respect to micro-environmental conditions were similar. While a number of seedlings survived at the sites on fallen logs and in mineral soil, almost no seedlings survived at the sites with either broad-leaved or coniferous litters at the end of the first growing season. The negative litter effect may kill most small seedlings of C. japonica. In addition, we found that survival rates of the seedlings were greater as the distance from the nearest adult and canopy openness increased. An analysis using Quantification Theory I showed that, of the possible micro-environmental factors, substrate conditions had the strongest effect on the survival of seedlings. The analysis also indicated that distance from the nearest adult and canopy openness also affected seedling survival significantly and to almost the same extent, although the effects were weaker than those for the substrate condition. Given the limited establishment sites for C. japonica seedlings, layering is suggested to be the main mode of regeneration in this forest. 相似文献
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进行样地调查与树干解析,以研究米槠生长过程。采用米槠容器苗和裸根苗造林,比较造林保存率、胸径、树高、冠幅、变异系数等指标,以了解两种苗木的幼林生长效应,并比较天然林与人工林米槠的早期生长。研究表明,米槠在10-20 a,树高、胸径生长较快;14-30 a,材积生长较快;树龄33 a时,尚未达到数量成熟阶段。米槠容器苗造林的保存率、胸径、树高值均大于裸根苗,其中保存率比裸根苗高9.5%,胸径值大11.3%,树高值大4.6%。比较人工林和天然林的早期生长,人工林树高和胸径值均大于天然林。米槠容器苗造林,可以促进米槠生长,取得较好的造林效果。 相似文献
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We initiated a study on a bottomland site in the southern United States to examine the effects of Japanese honeysuckle (Lonicera japonica Thunberg) control and seedlings of two root classes on survival and growth of underplanted cherrybark oak (Quercus pagoda Raf.) seedlings. Three honeysuckle control treatments were assigned to nine 0.5-ha plots in a stand harvested to 30% residual stocking. Treatments included a spring 1997 herbicide application (Escort®, metsulfuron-methyl), a similar application in the late summer of 1997, and a control (no herbicide application). In 1998, half of each treatment plot was planted with seedlings having four or more first-order lateral roots > 1 mm in diameter, while the other half of each plot received seedlings with fewer than four lateral roots. Four years after treatment, the early season application reduced honeysuckle biomass 60% relative to the other treatments, but we did not observe a survival or growth response by underplanted seedlings. Three years after establishment, seedlings that initially had four or more lateral roots were 16% taller and 18% larger in root-collar diameter than seedlings in the other class, but these differences were primarily due to initial size differences maintained through the study period. Over all treatments, oak seedlings averaged 87% survival while showing a 300% increase in height and a 170% increase in root-collar diameter 3 years after planting. Our results suggest that partial stand harvesting followed by underplanting may be a viable approach for establishing cherrybark oak reproduction on bottomland sites of the southern United States. 相似文献