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1.
采收期对3种笋用竹竹笋营养及氨基酸含量的影响 总被引：1，自引：0，他引：1
为探明不同采笋期对竹笋品质及营养成分的影响,对红哺鸡竹(Phylostachys iridescens)、白哺鸡竹(Ph.dulcis)和黄秆乌哺鸡竹(Ph.vivax'aureocaulis')3种笋用竹不同采笋期竹笋蛋白质、粗纤维、还原糖、灰分含量和氨基酸质量分数进行了测定.结果表明,3种笋用竹竹笋蛋白质干基含量均在310 g/kg以上,红哺鸡竹还原糖干基含量为107.0—188.1 g/kg,而白哺鸡竹和黄秆乌哺鸡竹还原糖含量分别为66.1—117.2,72.1—121.0 g/kg.3种笋用竹竹笋中粗纤维含量为43.0—84.2 g/kg,脂肪为26.0—36.0 g/kg.采收期异同不仅影响竹笋的粗纤维和灰分含量,也会影响到竹笋中蛋白质、脂肪、还原糖,但不同竹种的含量变化有所不同.红哺鸡竹竹笋中脂肪、蛋白质含量随采集时间的推后含量递减,但还原糖含量递增,而白哺鸡竹和黄秆乌哺鸡竹竹笋中脂肪、蛋白质含量随采集时间的变化不明显.3种笋用竹竹笋氨基酸总量(T)变化在13.06—35.4 g/kg,E/T值均在33.0以上.红哺鸡竹竹笋的T值随采收期的延后含量增加,而白哺鸡竹和黄秆乌哺鸡竹竹笋的T值则呈现出随采收期的延后含量递减,儿童必需氨基酸总量(CE)呈现类似的变化.竹笋营养成分和氨基酸的时令变化对于指导竹笋采集和竹林经营具有一定指导意义. 相似文献
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以常见食用竹笋毛竹(Phyllostachys pubescens)笋、石竹(Ph.nuda)笋为参照,对红哺鸡竹(Ph.iridescens)、白哺鸡竹(Ph.dulcis)、乌哺鸡竹(Ph.vivax)、黄秆乌哺鸡竹(Ph.vivaxf.aureocaulis)和早哺鸡竹(Ph.violascens)5种哺鸡竹竹笋的常规营养成分(粗蛋白、粗脂肪、不溶性膳食纤维和粗灰分)和矿质元素(P、K、Ca、Na、Mg、Cu、Fe、Zn和Mn)进行测定.结果表明:5种哺鸡竹竹笋的粗脂肪、不溶性膳食纤维含量均显著高于毛竹笋和石竹笋(p＜0.05);而在测定的其他营养成分方面,5种哺鸡竹竹笋与毛竹笋、石竹笋相当;黄秆乌哺鸡竹笋和乌哺鸡竹笋在粗蛋白、不溶性膳食纤维、P、Ca、Mg方面要显著高于其他3种哺鸡竹笋(p＜0.05);而白哺鸡竹笋的Fe含量最高. 相似文献
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《竹子研究汇刊》2018,(4)
采用最新的国际标准方法测定了刚竹属8种笋用竹种鲜竹笋蛋白质、粗纤维、还原糖、灰分等主要营养成分和氨基酸含量。结果表明,8种笋用竹种竹笋还原糖含量普遍为1.20～1.50 g·100 g~(-1),蛋白质含量为2.65～3.62 g·100 g~(-1)。以白哺鸡竹笋和红哺鸡竹还原糖含量较高,还原糖含量在1.40 g·100 g~(-1)以上;毛竹和花哺鸡竹为2种高蛋白竹种,蛋白质含量分别为3.62 g·100 g~(-1)和3.61 g·100 g~(-1)。红哺鸡竹口感较优,且粗纤维、灰分含量不高,是食用佳品。8种笋用竹种竹笋中氨基酸种类齐全,除了色氨酸外,16种常见的氨基酸均被检出,氨基酸总量(T)均高于大白菜、蒜苗、韭菜、芫荽、空心菜等常见蔬菜。白哺鸡竹竹笋和黄秆乌哺鸡竹竹笋的人体必需氨基酸(E)含量较高,E/T分别为37.704、36.029,超过了一般的蔬菜。甜竹、毛竹和高节竹竹笋中儿童必需氨基酸含量(CE)均在0.191 g·100 g~(-1)以上。 相似文献
4.
对浙江省临安太湖源竹种园引种的石竹、甜笋竹、雷竹、红竹、黄甜竹、高节竹、角竹、白哺鸡竹、乌哺鸡竹、水桂竹、黄皮刚竹、桂竹、四季竹等13个中小径笋用竹种的出笋成竹规律及其竹笋的营养成分进行观察、测定。结果表明,不同竹种出笋时间和昼夜生长节律不一致,雷竹和石竹笋期较早,黄甜竹、乌哺鸡竹、白哺鸡竹等笋期居中,黄皮刚竹和桂竹的笋期最晚;多表现出白天累计生长量大于夜间累计生长量的规律,而甜笋竹、红竹、水桂竹及乌哺鸡竹的昼夜节律却与之相反。不同竹种的竹笋营养成分含量不同,但均有较高的含水量和蛋白质含量,而脂肪含量较低,氨基酸种类齐全。本研究可为优良中小径散生笋用竹的引种扩繁提供参考。 相似文献
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白哺鸡竹(Phyllostachys dulcis)刚竹属。笋期4月中旬至5月上旬，其笋肉白嫩而鲜美，俗称“玉笋”，笋味明显优于毛竹笋、雷竹笋、高节竹笋等其它笋用竹。我省绩溪县瀛州乡、扬溪镇、伏岭镇等地有成片分布。适合于淮河以南丘陵岗地和四旁推广栽培。为了探求白哺鸡笋用竹林的丰产技术措施，笔者在绩溪县瀛州乡坑口村开展了白哺鸡笋用竹林低改培育试验。现将结果初报如下，供参考。 相似文献
9.
优质高产笋用竹种评选和配置 总被引：1，自引：0，他引：1
将我省10个主要的散生竹笋用良种集中成片种植在一起,按笋产量、笋期、笋价、笋个体大小、造林成本、投产年限、综合利用诸因子进行观察、评选,结果看出,最优类为早竹_1,优良类为早竹_2、白哺鸡、红竹、高节竹,角竹次之,石竹、刚竹、五月季、安吉金竹则不属优良范围。目前可以推广的笋用竹林,早熟的有早竹_1,中熟的有白哺鸡和红竹,晚熟的可选高节竹和角竹。考虑经营效益和市场需求,在城市附近及交通方便处,宜发展以鲜食为主的笋用林,竹种搭配以早竹_1为主,辅以中熟品种白哺鸡和红竹,晚熟品种面积不宜过大,在边远山区以生产加工笋罐头为目的笋用竹林,宜以晚熟高产的角竹、高节竹为主及中熟的红竹。 相似文献
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《Scandinavian Journal of Forest Research》2012,27(5):427-435
In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads. 相似文献
12.
《Scandinavian Journal of Forest Research》2012,27(3):206-217
The root systems of 2-yr-old Picea glauca, Picea mariana and Pinus banksiana seedlings were submitted to various frost temperatures during an artificial frost to induce different levels of root damage. Frost-damaged and control seedlings were placed in a greenhouse under high and low soil moisture regimes. Seedling growth and physiology were evaluated periodically. Seedling survival was reduced when root damage reached levels of 60-80%. Root systems of all three species showed partial to total recovery by the end of the experiment. In general, root freezing damage caused reductions in seedling growth, with these reductions becoming less significant over time. Root damage had little to no effect on black spruce and jack pine seedling physiology, while white spruce CO 2 uptake decreased with increasing root damage. Shoot nitrogen content of all three species decreased slightly with increasing root damage. 相似文献
13.
Contour hedgerows of multipurpose tree species in the sloping tea lands of Sri Lanka are expected to reduce soil erosion and
also add significant amounts of plant nutrients to the soil via periodic prunings. The objective of this experiment was to characterize the biomass decomposition pattern and quantify the
amount of nutrients added through prunings of six tree species (Calliandra calothyrsus, Senna spectabilis, Euphatorium innulifolium, Flemingia congesta, Gliricidia sepium and Tithonia diversifolia) currently being used in hedgerows associated with tea. Withered leaf and stem prunings (50 g) were enclosed in 2-mm litter
bags, placed at 5-cm depth and retrieved after one, three, six, nine and 12 weeks. Loss of initial dry weight, N, P and K
was measured. Single exponential decay function adequately described both dry weight and nutrient loss. Tree species differed
significantly in their rate of breakdown with decomposition constants (k) varying from 0.0299 to 0.2006 week−1 for leaves and from 0.0225 to 0.0633 week−1 for stems. Gliricidia showed the highest k for leaves with the rest in the following descending order: Senna > Tithonia ≥ Euphatorium > Calliandra > Flemingia. A similar pattern was observed for loss of all nutrients with Calliandra and Flemingia always having lower k values than the rest. Although N immobilization was not observed, immobilization of P and K was observed
during the first week of incubation in some species, particularly in stem prunings. Annual biomass of prunings differed significantly
between tree species in the following descending order: Calliandra > Senna > Flemingia > Tithonia > Gliricidia > Euphatorium. Calliandra added the greatest amount of nutrients annually to the soil with Euphatorium adding the least. Calliandra prunings provided the annual total K requirement and 49% of the N requirement of mature tea. However, none of the species
provided more than 5% of the P requirement. It is concluded that among the tree species tested, Calliandra and Flemingia are the most suitable for contour hedgerows in tea plantations of this agroclimatic region because of their higher soil nutrient
enrichment capacity and slower decomposition rates which would minimize leaching losses.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
14.
《Scandinavian Journal of Forest Research》2012,27(2):118-130
The effects of seed weight and seed type on seedling growth of Pinus sylvestris (L.) were studied by seeding individually weighed orchard and stand seed in different mixtures under harsh (direct seeding in field) and optimal (seeding in nursery) conditions. In the nursery experiment an increase in the seed weight from 3 to 7 mg increased the seedling height by 10-27% and total weight by 27-113%, and decreased the height/diameter ratio by 5-6% after 2 yrs. With elimination of seed weight effects, orchard seedlings were 2% taller than stand seedlings in year 2. Without elimination of seed weight effects, orchard seedlings were 7-13% taller. In the field experiment an increase in the seed weight from 3 to 7 mg increased seedling height by 18-65%, stem volume by 81-274% and the number of top-buds by 23-34% in year 5. After elimination of seed weight effects, orchard seedlings were 7-13% taller than stand seedlings and without elimination of seed weight effects 20-21% taller after 5 yrs. Even after elimination of both seed weight and genetic effects orchard seedlings were 3-9% larger than stand seedlings in the field experiment. In conclusion, the influence of seed weight and seed type on growth traits and slenderness is highly significant and the influence seems to be greater in harsh conditions. 相似文献
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Astra Zaluma Lauma Bruna Darta Klavina Natalija Burnevica Kristine Kenigsvalde Andis Lazdins Talis Gaitnieks 《Forest Pathology》2019,49(6)
Heterobasidion parviporum and Heterobasidion annosum are widely distributed root‐rot fungi that infect conifers throughout Europe. Infection of conifer stumps by spores of these pathogens can be controlled by treating fresh stumps with a competing non‐pathogenic fungus, Phlebiopsis gigantea. In this study, growth of three Latvian strains of P. gigantea and the biological control agent ‘Rotstop’ strain was evaluated in stem pieces of Norway spruce, Scots pine, lodgepole pine, Douglas‐fir, Weymouth pine, Siberian larch and Sitka spruce. The growth rates of one H. parviporum and one H. annosum isolate were also measured in the same stem pieces. The growth rate of P. gigantea varied greatly in wood of different conifer species. It was higher in the three pine species, lower in Norway spruce and lowest in Sitka spruce and Siberian larch, and in Douglas‐fir, this fungus did not grow. The largest area of wood occupied by P. gigantea was in lodgepole pine. Growth of Latvian isolates of P. gigantea in the wood of Pinus and Picea species was comparable to that of the Rotstop isolate. Consequently, stump treatment with local P. gigantea isolates should be recommended. However, our results suggest that Douglas‐fir stump treatment against Heterobasidion by P. gigantea may be ineffective and other stump treatment methods should be considered. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(1):53-61
This study investigated the stand structure in pine, spruce and deciduous forests in the border district of Finland and Russia. A total of 46 mature forest stands was selected as pairs, the members of each pair being as similar as possible with respect to their forest site type, age, moisture and topography. The stands were then compared between the two countries by means of basal areas and number of stems. The proportions of dominating tree species were 2-12% lower, and correspondingly the proportions of secondary tree species higher, in Russian forests. The density of the forest stock was also higher in each forest type in Russia. The forests in the two countries differed most radically in terms of the abundance of dead trees. The amount was two to four times higher in Russian deciduous and spruce forests, and in pine forests the difference was 10-fold. The stand structures indicated that Russian coniferous stands, in particular, were more heterogeneous than intensively managed pine and spruce stands in Finland. 相似文献
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《Scandinavian Journal of Forest Research》2012,27(1):15-27
The root collar diameter and the height:diameter ratio are of particular importance in container-grown seedlings where a high density in the containers may produce spindly seedlings. Temperature regimes and light quality are known to affect plant growth. The aim of this study was to identify responses in Picea abies (L.) Karst. seedlings grown with light providing different red:far-red ratios and under temperature regimes with alternating day (DT) and night temperature (NT) from negative (DT < NT) to positive (DT > NT) difference (DIF) between DT and NT. Experiments were conducted in controlled environment chambers and in a daylight phytotron. Only limited thermoperiodic responses appeared in P . abies seedlings with respect to seedling height and dry weight accumulation. The formation of terminal buds, however, was clearly delayed in seedlings grown at negative DIF. The results indicate a requirement for day extension light that is high in far-red, to prevent terminal bud formation under natural short-day conditions. An extended study should be conducted to clarify the minimum level of light intensity and the optimal light quality needed to prevent terminal bud formation under natural short-day conditions. 相似文献
18.
本文分析了CAD在设计中引起的正面和负面影响,并进行了系统的阐述,从而使设计者在应用中能够保持客观的态度。 相似文献
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Steven Maranz Amadou Niang Antoine Kalinganire Djeneba Konaté Bocary Kaya 《Agroforestry Systems》2008,72(3):231-239
Baobab leaves form an important part of the local diet in Sahel countries and elsewhere in Africa. Existing leaf nutritional
data and agroforestry performance information are based solely on Adansonia digitata L., the baobab of continental Africa. The introduction potential of Adansonia species from the center of diversity in Madagascar and from Australia remains untapped. To assess this potential, the mineral
contents and B1 and B2 vitamin levels of dried baobab leaves were determined for five-year old trees of A. digitata, A. gibbosa (A. Cunn.) Guymer ex D. Baum, A. rubrostipa Jum. & H. Perrier (syn. A. fony Baill.), A. perrieri Capuron and A. za Baill. grown in an introduction trial in Mali. Nutritional data were evaluated against survival and vigor to identify promising
germplasm. Leaf vitamin and crude protein contents were highest in the Madagascar species, especially A. rubrostipa (B1 88 mg 100 g−1, B2 187 mg 100 g−1, protein 20.7% dry weight). However, the local species far outperformed the introductions in survival, tree height, basal
diameter and resistance to termites. We suggest grafting as a way of harnessing the vigor of well-adapted local baobab varieties
to the superior nutritional profiles of A. rubrostipa and others. Cross-species grafting tests in Adansonia were successful, thus creating new agroforestry possibilities with different scion/rootstock combinations. 相似文献
20.
《Wood material science & engineering》2013,8(2):76-84
Abstract Wood in general and wooden studs in particular are often distorted owing to uneven shrinkage during the drying process in the sawmill. Twist is often the most detrimental of all types of distortion, and it is caused by spiral grain in combination with variations in moisture content. For sawmills, the objective is to produce dried, straight boards, and one method of dealing with boards with excessive spiral grain is to sort them out and then dry them in a pretwisted position to obtain straight boards after drying. A model using the finite element (FE) method for the simulation of drying twist distortions was first calibrated against laboratory experiments in which boards were dried with and without restraints and pretwists. After the calibration, the FE results were compared with industrial test results for boards that were dried without restraints or with restraints with zero pretwist, i.e. straight restraints. The FE model used an elastic–ideally plastic material model to obtain permanent deformations. The calibration was to set the yield stresses so that there was a good match between FE results and results from the laboratory experiments. The comparison between the industrial test results and the FE results showed that the FE model is capable of realistic simulations of drying boards with and without restraints and presumably also pretwists. 相似文献