浙江省杨梅大小年的成因及其对策

分析了杨梅大小年的成因基础，指出了必须因树因地制宜，抓住施肥管理为中心，辅之适当疏花疏果手段，以缓解花果发育和抽梢生长之间的矛盾，从而为克服或缩小杨梅大小年结果的现象提出了一系列措施。     

疏花剂对杨梅结果大小年的调控效果

研究施用"疏六"疏花剂对3个杨梅品种结果状况、果实品质及翌年树体状况的影响.结果表明:大年施用疏花剂可明显减少杨梅花朵数量及坐果率,使杨梅果实成熟期提前,单果重提高,并且果实着色及可溶性固形物均得到明显改善.此外,小年产量得到大幅提高,经济效益显著,调节效果明显,且一次调节持效多年.疏花剂对3个品种的作用效果是:'早梅'＞'木叶梅'＞'荸荠种'.建议使用疏花剂最适合浓度为3g/L.     

明月梨大小年形成的原因及其调节措施

明月梨生长旺,树体大,寿命长,单株产量高,在湖北省梨树栽培中占有一定的比重。明月梨的缺点是容易出现大小年结实的现象,成年单株大树年结果量可达数百斤之多,小年结果极少或不结果,产量极不稳定。为了找到有效的调节措施,对明月梨大小年进行了调查分析。     

油茶大小年结果及其生物学特征

将油茶个体分为大年树、小年树、连年小年树和稳产树4个类型,调查研究了油茶大小年结果的生物学特性。研究表明:花芽数量是产生大小年的直接原因,座果量与上年花芽数量呈抛物线关系,y=-0.0193x~2+0.8687x-1.1039;着果量与其并存的花芽数量呈指数函数关系,lny=0.7879ln l/x+2.7286。此外还研究了各结果类型树的春梢枝、春梢叶和果的生长动态特征。     

缩小银杏结果大小年的技术措施

银杏是多花树种，分化的花芽和开放的雌花大大超过其座果能力，容易引起重载。产生结果大小年现象的主要原因是养分不足或养分不全、人工授粉不当、病虫危害及环境条件等。缩小大小年差异，保持年年丰产稳产的技术措施包括：实行科学配方施肥、适时适量人工授粉、改善生长环境、防治病虫害、增强树势。自1996年在泰兴市推广应用后，白果产量稳中有升，结果大小年变异系数由1991-1995年的38.8%下降到1996-2000年的25.4%，年均增加收入1468.2万元。     

大小年毛竹林改造试验

在福建省尤溪县西滨镇彩洋村,对大小年明显的毛竹林实施大年强度采伐、定量留养、控制新竹数量,合理施肥,小年留笋养竹等技术措施。实施5 a后结果表明:改善了竹林的生长条件和竹林结构。竹林密度增加84.8%,立竹平均胸径从8.6 cm提高到10.1 cm,竹笋产量增加18.9%。竹材产量增加47.8%。Ⅲ度以下的青壮竹占全林竹的75.6%,Ⅳ度以上老竹从试验前27%下降到24.4%,小年竹占立竹总数的43.8%,每年林地孕笋竹和换叶竹的数量达到相近,完成了大小年转变到花年毛竹林的改造。     

宁国山核桃结果大小年成因及对策

宁国市是山核桃之乡，现有山核桃面积23．8万亩，年产量可达3800吨，已成为宁国市林农经济收入的主要来源。但山核桃结果大小年十分明显，如何消除大小年的差别根据笔者多年的观察和试验，并走访了果农，找出造成结果大小年的原因。并采取相应的管理措施：     

杨梅优良新品种配套栽培技术

杨梅是亚热带的特产果树,我国南方最具特色生态的经济物种,适应性广泛,在南方绝大多数山坡地的微酸性土壤中都能生长,并表现出良好的性状.实践证明,种植杨梅具有极好的经济、社会与生态效益.现将浙江森禾种业股份有限公司选育的东方明珠、紫水晶杨梅良种配套栽培技术,简要介绍如下.     

杨梅早果丰产栽培技术

本项目是引种栽培试验示范研究课题，在具体实施过程中，根据杨梅的生物学特性和生态习性，结合当地的自然备件，运用种源区常规适用技术与先进的科学技术、科技成果相结合，成功地研究了适合当地自然、生态、环境条件的杨梅早果丰产栽培技术体系。     

二都杨梅矮化密植栽培技术初探

二都杨梅基地建设是上虞市"四季仙果"之旅的重点之一,近年来基地建设发展较快,为突破二都杨梅传统栽培产出时间长的难题.从2005年开始,通过对三个地块五年的二都杨梅矮化密植栽培试验,开展深红种杨梅大苗密植,在整枝修形、促花疏果等重要环节采取去主枝培养矮化开心型树冠、叶面喷施多效唑等技术措施,促使株形矮化、及早形成花芽并实...     

Roles of gibberellins and abscisic acid in dormancy and germination of red bayberry (Myrica rubra) seeds

Intact seeds from freshly harvested fruits of Myrica rubra (Sieb et Zucc.) were dormant and required 8 weeks of warm stratification followed by 12 weeks of cold stratification for germination. Exogenous application of gibberellic acid (GA(3)) to intact fresh seeds was effective in breaking dormancy, with > 70% of seeds germinating when treated with 5.2 mM GA(3) and incubated at a day/night temperature of 30/20 degrees C for 20 weeks. Removing the hard endocarp or endocarp plus seed coat of fresh seeds promoted germination, and addition of GA(3) to the embryo accelerated germination. The gibberellins GA(1) and GA(4) were more effective than GA(3) in promoting germination of seeds with the endocarp removed. Endogenous contents of GA(1), GA(3), GA(4), GA(7) and GA(20) were quantified by gas chromatography-mass spectrometry-selected ion monitoring in the endocarps, seed coats and embryos of fresh seeds treated with 5.2 mM GA(3). The content of GA(3) decreased in the endocarp during incubation, whereas GA(1) contents increased in the endocarp and seed coat. A high GA(1) content was detected in the endocarps and embryos of newly germinated seeds. We speculate that GA(3) was converted to GA(1) during incubation and that GA(1) is involved in seed germination. Endogenous abscisic acid (ABA) contents were measured in fresh seeds and in warm and cold stratified seeds. The ABA content in fresh seeds was distributed in the order endocarp > seed coat > embryo, with the content in the endocarp being about 132-fold higher than in the seed coat and embryo. Total ABA content of seeds subjected to warm or cold stratification, or both, was 8.7- to 14.0-fold lower than that of fresh seeds. Low contents of endogenous GA(1), GA(3), GA(7) and GA(20), but elevated contents of GA(4), were found in the seed coats and endocarps of warm plus cold stratified seeds and in the seed coats and embryos of newly germinated seeds. These observations, coupled with the finding that GA stimulated germination of dormant Myrica seeds, provide evidence that endogenous ABA inhibited release of dormancy and that endogenous gibberellins, especially GA(4) or GA(1), or both, are involved in germination.     

砀山酥梨PBO脱萼试验

探讨了喷施PBO对砀山酥梨果实脱萼的适宜时间和浓度。试验结果表明,PBO对砀山酥梨具有良好的脱萼效果;在开花前5～7d至盛花末期,喷施越早,效果越好;落花后脱萼效果明显降低。喷施浓度250～300倍液效果最好。     

施用硼肥对白糖杨梅生长发育的影响

白糖杨梅是一种深受人们喜爱的珍稀杨梅品种,但其产量很低,硼素营养缺乏是一个重要原因。本文采用田间试验的方法研究硼素营养对白糖杨梅生长发育的影响。结果发现,硼素对白糖杨梅的生长发育有显著的影响。叶片硼、全氮、全磷及全钾的含量均随硼肥用量的增加而增加,果实的坐果率、粗蛋白、粗纤维、粗灰分、全氮、全磷及全钾含量也随硼肥用量的增加而增加。在本试验条件下的浓度为4.00g/L的硼砂处理较为适宜。     

绿源贝钙粉肥在早酥红梨上的应用试验

为了解施用绿源贝钙粉肥对早酥红梨果园土壤和早酥红梨树生长发育及果实品质的影响情况,设置绿源贝钙粉肥施用量分别为2、3、4 kg·L-1的3个施肥处理和1个对照处理(即不施用绿源贝钙粉肥)进行了田间试验。结果表明:加施了4 kg·L-1绿源贝有机钙粉肥的早酥红梨其果梗生长量比对照提高18.45%;百叶质量比对照提高66.51%;其果实纵径生长量比对照提高22.55%,其横径生长量比对照提高19.67%;其单果质量比对照提高58.81%;其果实中的固形物含量比对照提高18.97%。这一试验结果说明,绿源贝钙粉肥对早酥红梨的生长发育和果实品质均有明显的促进与改善作用。     

First-year survival and height-growth of red ceiba following various site preparation techniques on vertic soils in northern Colombia

If growth of red ceiba, Bombacopsis Quinata (Jacq.) Dugand, is to be increased in plantations established on Vertisols, site preparation techniques must be identified to overcome the soil management difficulties of these soils. This research was conducted to identify specific site preparation techniques appropriate for Vertisols that increase survival and height growth of red ceiba. The effects of subsoiling within the row (prior to planting) to depths of 40 and 60 cm, subsoiling between the rows, and additions of organic mill waste on red ceiba survival and height growth, soil water content, bulk density, and penetrometer resistance were investigated. The soil was a very fine, montmorillonitic, isohyper-thermic Entic Chromustert. No difference in survival due to subsoiling was found, but the additions of mill waste significantly decreased survival after 1 year (94.7%) compared to the control subplot (98.7%). Height was increased by subsoiling to the 40-cm depth (92.3 cm) and to the 60-cm depth (97.4 cm) over no subsoiling (80.7 cm). Trees on the subplots receiving mill waste were significantly lower in height (83 cm) compared to the control subplots (93.1 cm) and the subsoiling between the planting rows subplots (94.2 cm). Survival was most highly correlated with bulk density at the 50-cm depth within the planting row (r=–0.44) and height with soil water content at the 30-cm depth within the planting row (r=–0.56). Subsoiling affected height more than survival. Subsoiling to 40 cm is the most cost-effective treatment. Mill waste addition did not improve height or survival, possibly due to harmful decomposition by-products.     

高等级公路边桩放样的一种新方法

针对高等级公路边桩传统放样方法的不足,提出了一种通过计算路线外任一点至道路中线最短距离放样高等级公路边桩的方法。该方法能大大提高边桩放样的精度与速度。     

A model-based performance test for forest classifiers on remote-sensing imagery

Ambiguity between forest types on remote-sensing imagery is a major cause of errors found in accuracy assessments of forest inventory maps. This paper presents a methodology, based on forest plot inventory, ground measurements and simulated imagery, for systematically quantifying these ambiguities in the sense of the minimum distance (MD), maximum likelihood (ML), and frequency-based (FB) classifiers. The method is tested with multi-spectral IKONOS images acquired on areas containing six major communities (oak, pine, fir, primary and secondary high tropical forests, and avocado plantation) of the National Forest Inventory (NFI) map in Mexico. A structural record of the canopy and optical measurements (leaf area index and soil reflectance) were performed on one plot of each class. Intra-class signal variation was modelled using the Discrete Anisotropic Radiative Transfer (DART) simulator of remote-sensing images. Atmospheric conditions were inferred from ground measurements on reference surfaces and leaf optical properties of each forest type were derived from the IKONOS forest signal. Next, all forest types were simulated, using a common environmental configuration, in order to quantify similarity among all forest types, according to MD, ML and FB classifiers. Classes were considered ambiguous when their dissimilarity was smaller than intra-class signal variation.