南方沿海地区翠冠梨整形修剪技术

翠冠梨，是我国南方近年推广发展最快、栽培面积最大的优质早熟梨新品种。我区自1996年开始集约化推广种植。目前栽培面积已达1000hm^2，投产园平均每667m^2效益超过4000元。已成为全省早熟梨高效栽培的重点和优势地区。根据我地台风多、湿度大等气候特点以及翠冠梨的生物学特性，通过几年来的实践，摸索出翠冠梨在露地常规栽培条件下的稳产、优质修剪技术。现介绍如下。     

杏树自然开心形整形修剪技术

杏树的整形修剪方法与其栽植密度、经济效益密切相关。目前,栽植密度多为2～3m×3～4m。杏树干性不强,特别喜光,树形宜采用自然开心形。我们试验的自然开心形整形修剪技术,具有成形快、结果早、产量高等特点。现将该技术介绍如下。1 自然开心形的基本结构 主干高60cm,主枝5～6个,主枝开张角度70°,主     

三主枝开心形梨树整形修剪技术要点

三主枝开心形梨树树形成开张状态,使得树体各个方位均能满足对光照的需求,且果实成熟度相对均匀一致、含糖量高,通风透光好,果品质量好、商品率果实高。该树形结构简单,整形修剪容易,便于进行标准化栽培,故该技术适于在生产上推广运用。     

桃树三主枝改良开心形整形修剪法

合理的树体结构是果树丰产的基础。为探讨不同树形对桃产量的影响,笔者于1995年开始对桃树自然开心形进行改良。经对比观察,三主枝改良开心形能明显提高产量,比传统自然开心形提高产量30％以上。     

梨双层开心形整形修剪技术

湖北省老河口市现有梨栽培面积5 6 70ｈｍ2 ,年产量 9 5万ｔ,其“汉水牌”优质梨畅销我国东南沿海地区、港澳地区及俄罗斯。在栽培管理过程中 ,我们推广梨双层开心形整形修剪技术 ,树体结构稳定 ,操作简单 ,管理方便 ,洪山咀街办大面积产量连年稳定为 2 5 0 0～ 30 0 0ｋｇ/ 6 6 6 7ｍ2 ,优质果率 80 5 %。现总结如下。1　合理树体结构树冠半圆形 ,树高 2 5～ 3 0ｍ ,冠径3 5～ 4 0ｍ ,具中心领导干 ,干高 40～5 0ｃｍ ,主枝分两层。第一层 3～ 4个主枝 ,基角为 6 0～ 70°,按近似 90°或 12 0°方向均匀分布 ,主枝间距 10～ 15ｃｍ ,层…     

梨枣开心形整形修剪技术

梨枣开心形树形每株有4～5个主枝,冬季疏除主枝和侧枝上所有结果枝组、包括延长部位的二次枝。结果枝组由当年春季萌发的枣头培养而成,每个主枝保留4～6个枣头、每个枣头保留4～5个二次枝摘心。该法修剪延迟开花15天左右,避过麦收干热风,坐果率和果实品质皆有提高,且树体容易保持丰产稳产。     

翠冠梨优质稳产修剪技术

翠冠梨是我国南方地区栽培面积最大的梨品种,我们自1996年开始在宁波市鄞州区推广该品种,目前宁波市鄞州区翠冠梨栽培面积已近1 000 hm2,投产梨园平均每667 m2收益超过4 000元,鄞州区已成为浙江省梨树高效栽培的重点产地和优势地区.几年来,我们总结提出在当地沿海台风多、温度高、降雨频、湿度大等气候条件下翠冠梨露地栽培优质稳产修剪技术,该项技术已经全面应用于生产中,现介绍如下.     

苹果开心形整形修剪关键技术

1　树形结构特点及整形技术开心形苹果树的树形特点及整形技术主要包括以下 3个方面 :1 .1　落头开心落头开心须在苹果树长势基本稳定、花芽大量形成之后开始 ,该期苹果树的小冠形树体结构基本形成 ,在接近落头区域形成了枝组健壮、花芽充裕的主枝。冬剪时 ,可视树体长势逐年从主干上端向下落头 ,将苹果树的顶端优势转化为横向优势 ,垂直生长转变为水平延伸 ,从而减小了叶幕厚度 ,特别适宜于富士、珊夏等喜光性苹果品种的优质生产。落头开心通常从定植 5～ 6a(年 )开始 ,先是落头到永久性主枝以上的小型结果枝上 ,以后逐渐下移 ,最后定位于…     

杏树自然开心形修剪技术

杏树干性不强,特别喜光,宜采用自然开心形。自然开心形具有成形快、结果早、产量高等特点。下面就自然开心形的修剪技术介绍如下。     

我国苹果树开心形改造应注意的问题

我国苹果树形改造期间存在树形改造力度、主枝结构、枝组培养密度和长度、果园群体密度等问题。我们提出了解决上述问题的方法和技术思路。     

刻芽对梨树生长的影响

目前南方优质梨的栽培多用密植栽培方式，在幼树期间采用轻剪缓放、促发分枝、提高萌芽率等措施，是实现促进幼树快速形成早果丰产的基本途径。刻芽是其中一项重要措施。为了摸清刻芽的基本规律，笔者于2005年进行了试验。     

梨树恶疫霉的生物学特性研究

宝珠梨疫腐病是云南省的一种新记录病害 ,其病原菌为恶疫霉〔Phytophthora cactorum(L ebert et Cohn) Schrot〕。适宜恶疫霉的培养基是番茄汁、V8汁和 PDA培养基。适宜恶疫霉生长的p H值 3～ 10 ,最适 p H值为 5～ 6 ,适宜生长的温度范围 10～ 30℃ ,最适生长温度为 2 0～ 2 5℃。恶疫霉对果糖、麦芽糖、蔗糖等碳源的利用好于其它碳源 ,对酵母膏、天门冬酰胺、牛肉膏等氮源的利用好于其它氮源。     

树盘覆黑膜对梨树生长及矿质营养含量的影响

对梨树树盘覆黑膜后树体营养生长和果实生长指标、叶片及果实矿质营养含量的测定。结果表明,树盘覆黑膜梨树叶片相对含水量、叶绿素相对含量和果实可溶性固形物含量显著提高;影响叶片和果实中矿质营养含量。为梨树树盘覆黑膜能促进生长和提高果实品质提供理论依据。     

梨树病虫害综合防治技术

梨树为我国主要果树品种之一，分布遍及全国各地。在梨树生长发育过程中，常受到多种病虫害的危害。常见病虫害主要有：梨黑星病、梨锈病、黑斑病、轮纹病、干腐病、叶肿病、食心虫、蚜虫、蝽类、刺蛾、蚧壳虫、蚱蝉等，这些病虫害常给梨树生产带来严重损失。     

梨树高接换优技术要点

梨树高接换优后,品种新,结果早,可获得较高的经济效益.1999年,大兴区梨树由于品种滞后、管理不到位、效益低下等问题,许多果树无人承包.甚至出现了砍树的局面.为了保护果树资源,大兴区从2000年开始,有目的地从国内外引进'丰水'黄金'园黄'阿巴特'早红考密斯'凯斯凯德'等梨优新品种200余个进行试验、示范.     

Cell wall metabolism of pear fruit on the tree after 2,4-DP treatment

Summary

The effect of 2,4-dichlorophenoxy-propionic acid (2,4-DP) on fruit ripening on the tree was investigated in `La France' pears (Pyrus communis L.). Forty-five ppm, 2,4-DP solution was applied at 159 d after full bloom (DAFB), which was optimum harvest date for `La France' pears. They were compared with fruit harvested at 159 DAFB and placed in a controlled room with a 208C and 90% r.h. After harvest, the fruit firmness decreased dramatically 13 d after harvest (DAH). In 2,4±DP treatment, the levels decreased gradually 13 d after treatment (172 DAFB). In the untreated control, the levels also showed a slight decrease with time. Final ethylene concentration was almost the same in harvested and 2,4-DP treated fruit, but lower in the untreated control. In each treatment, water-soluble polyuronide (WSP) concentrations increased with time and hexametaphosphate-soluble polyuronide (HMP) and HCl-soluble polyuronide (HP) concentrations decreased. WSP concentration increased rapidly 20 DAH in harvested fruit and 194 DAFB in 2,4-DP treatment. Harvested and 2,4-DP treated fruit reached the edible condition on 17 DAH and 194 DAFB, respectively. Pectinesterase (PE) activity increased slightly with time for all treatments, showing no significant difference between treatments. Polygalacturonase (PG) activity increased gradually in all cases, being higher in 2,4-DP treated fruit than in control fruit left on the tree. These results suggest that 2,4-DP treatment before harvest induces pear fruit softening. This implies that 2,4-DP may be used as a replacement for low-temperature storage to promote the ripening, and good quality ripe fruit with buttery and juicy texture may be harvested on the tree.     

梨树苹毛丽金龟和蚜虫的生物药剂防治试验

研究了苦皮藤素、藜芦碱、苏云金杆菌和球孢白僵菌4种生物制剂对梨树苹毛丽金龟和蚜虫的防治效果。结果表明,喷药后48小时,对苹毛丽金龟的防治效果以1%苦皮藤素1000倍液97. 5%的最高,显著高于苏云金杆菌1000倍液的95. 0%、球孢白僵菌1500倍液的92. 5%和0. 5%藜芦碱1000倍液的87. 5%,均为防治苹毛丽金龟的有效药剂。防治梨蚜虫,4种药剂的防效达到98. 2%～99. 8%,4种药剂间无显著差异,均为防治梨蚜虫的有效药物。     

Fifteen years of observations on the agronomic behaviour of seven heat-treated pear tree cultivars

Performance of heat-treated clones of seven pear cultivars in a contaminated orchard were observed over 15 years and compared with non-treated clones (virus infected) of the same cultivars. The heat-treated clones were more successful in budding, had a 10% increase in vigour, 15–50% better cropping depending on the cultivar. The yield per tree size varied between the heat-treated and non-treated from 3 to 16 kg per tree per centimetre trunk girth. Only “Général Leclerc” proved an exception: the treatment seemed to have brought about the appearance of a “variant” which flowered later and had a smaller yield. Throughout the 15 year study period we did not observe any natural viral contamination in the orchard.     

Health status of the pear tree following the establishment of Fire blight in Northern Tunisia

ABSTRACT

Pears have great importance in Tunisia for their desirable taste and commercial value. Until 2012, the pear cultivation was protected against fire blight by the application of a rigorous quarantine system. Fire blight, caused by Erwinia amylovora, was outbreak in Tunisia in the spring of 2012 and has spread rapidly through the most important pear growing regions destroying several hundred hectares of pear plantations. Therefore, the total pear production has decreased from 60,000 metric tons in 2011 to less than 20,000 metric tons in 2016. In this study, collected data of pear culture and surveys were carried out during four years (2012–2016) in the main pear growing areas to evaluate the current situation of the disease in the country particularly in the damaged regions of the lower valley of Medjerda (Manouba, Ben Arous, Bizerte, and Beja). Samples collected from symptomatic trees were processed for the isolation and identification of the causal agent using microbiological and molecular techniques. The results indicate that the disease had destroyed more than 5500 hectares among a total of 8400 hectares of pear plantations area. Both provinces Manouba and Ben Arous were the most affected by fire blight disease resulting in the eradication of 350 and 325 hectares of pear plantations, i.e., 100% and 98% of the total infected area, respectively. All control attempts, including sanitary measures, the application of mineral oil and copper, growth regulators and biological control have failed to limit the spread of the disease. The presence of pathogen in the prospected regions was confirmed by pathogenicity and molecular tests, which are compatible with the symptoms observed throughout the surveys. The pear cultivation in Tunisia is threatened by fire blight due to the restriction tolerance of the available varieties and the climatic conditions favoring the staggered flowering of the species. Quarantine measures must be implemented to prevent the spread of this disease in a new disease-free areas.