PBO与福星处理对湘南梨脱萼及其果实品质的影响

以湘南梨为试材,于盛花期喷施PBO和福星不同处理,研究PBO和福星对湘南梨脱萼果率、果实品质和单株产量的影响。结果表明：喷施浓度为300倍 PBO和6000倍福星混合处理脱萼效果差异最为显著,脱萼果率为73.90%;单独使用PBO处理脱萼率为47.60%;两种脱萼处理均能够显著提高梨果的可溶性固形物和可溶性糖的含量,增加梨果的果肉硬度,降低果形指数,改善梨果外观品质,但对梨树的单株产量的影响差异不显著。     

植保无人飞机不同施药模式对Y形梨树雾滴沉积分布研究

为了研究油动单旋翼植保无人飞机采用“行间飞”和“Y间飞”2种飞行施药模式对Y形梨园进行喷雾作业后雾滴在Y形梨树冠层中的沉积分布规律,以30 g/L的诱惑红85水溶液为喷雾剂,铜版纸为雾滴收集卡,设计了4种不同作业速度梯度对Y形梨树喷雾效果试验,研究对比了不同飞行速度条件下2种飞行施药模式的雾滴沉积分布情况。试验结果表明：采用“行间飞”飞行施药模式喷雾时,雾滴在Y形梨树主枝外部的沉积密度高于在内部的沉积密度雾滴,且飞行速度为2 m/s和3 m/s时的沉积密度比飞行速度为4 m/s和5 m/s的沉积密度显著偏高。“Y间飞”飞行施药模式下雾滴在Y形梨树冠层不同位置的雾滴沉积分布更均匀。在风速小于1.3 m/s的微风条件下,当使用油动单旋翼植保无人飞机以距离Y形梨树冠层顶部2 m的高度喷雾作业时,应当采用“Y间飞”飞行施药模式,同时飞行速度以2?3 m/s为宜,此时雾滴的沉积密度在冠层内部和外部均大于15个/cm2。研究结果可以为使用植保无人飞机防控梨园病虫害提供喷雾技术依据。     

‘新高’、‘鸭梨’果实发育过程中果肉及种子内源激素的变化

为探索梨种子对果实生长发育的影响,通过高效液相色谱（HPLC）技术对‘鸭梨’和‘新高’果实发育期间果肉和种子中内源生长素（IAA）、赤霉素（GA3）、脱落酸（ABA）和玉米素（ZT）含量变化进行了测定。实验结果表明：两个品种种子中ABA和ZT含量变化基本相似,但新高ABA、ZT含量高于鸭梨,鸭梨IAA含量随着果实的发育处于下降趋势,而新高先升高后降低,鸭梨GA3含量随着果实发育先下降后上升,而新高出现两次高峰一次低谷且整体下降的趋势。两个品种果肉中IAA、GA3、ABA和ZT含量变化趋势基本相似,新高IAA、ABA含量高于鸭梨,70天之前新高GA3含量高于鸭梨,然而随着果实发育,鸭梨GA3含量又高于新高,并且鸭梨出现两次高峰,果实发育到80天后,新高ZT含量高于鸭梨。     

梨树省力化液体授粉技术

梨属于自花授粉不结实性果树,生产中多采用配置授粉树或人工授粉等方法进行授粉,但易受气候变化或作业时间短、人工成本高等影响,造成授粉受精不良。我中心研发了一种梨树液体授粉方法,并通过多年的推广应用实践,已形成一项成熟的梨树省力化液体授粉技术。本文主要介绍该技术的实施方法与注意事项。     

‘鸭梨’、‘新高’果实发育过程中果肉及种子有机酸含量的变化

为了研究梨种子对果实生长发育的影响,采用高效液相色谱(HPLC)技术对‘鸭梨’和‘新高’果实发育过程中果肉和种子中的有机酸含量进行了分析。结果表明：两个品种果肉中主要的有机酸组分均为苹果酸和奎尼酸,发育初期‘鸭梨’与‘新高’果肉中各组分的比率相近,但果实成熟时‘新高’果肉中苹果酸的比率59.98%显著高于‘鸭梨’的37.51%;两个品种种子中的有机酸组分比率的动态变化相近,与果肉相反,主要表现在奎尼酸比率的增加和苹果酸比率的减少。两个品种果肉和种子中的总酸、草酸、奎尼酸,苹果酸,莽草酸,柠檬酸含量均随着果实的成熟呈下降趋势,‘鸭梨’果肉中的奎尼酸、莽草酸、柠檬酸含量高于‘新高’;‘新高’在果实成熟时种子中的总酸含量4.59mg/g显著低于‘鸭梨’13.00mg/g,‘鸭梨’成熟果实种子中的草酸、奎尼酸、莽草酸含量显著高于‘新高’;在果实发育初期,种子中的苹果酸含量极显著高于果肉,在果实成熟时则显著低于果肉。     

Screening fruit tree genetic resources in Belgium for disease resistance and other desirable characters

Summary The wide diversity of old fruit-tree cultivars originating or introduced into Belgium during the 18 ^th and 19 ^th centuries was collected as far as feasible over the last fifteen years at the State Plant Pathology Station in Gembloux. Out of the 2400 accessions now collected, one quarter was recovered from old public collections, and three quarters came from farms or gardens. The initial intention was to screen the material for disease resistance and other characters of agronomic interest with a view to using the best cultivars as breeding parents. However, as the collection developed, genetic resources conservation also became an objectiveper se. The collection presently contains 1150 apple, 850 pear and 300 plum accessions, and smaller numbers of other fruit species. Each accession is evaluated in an experimental orchard for at least ten years. In view of the growing public interest in old fruit-tree cultivars, the Plant Pathology Station has for several years been releasing to the nursery trade the better cultivars emerging from the evaluation, namely nine apple and four plum cultivars, and one peach cultivar. The principal features of the apple cultivars are presented in this paper. Since 1988, old apple and plum cultivars have been being used at the Station as parents in a breeding programme, with both controlled and open pollination. In some instances, old apple cultivars have also been crossed with a modern parent carrying the Vf gene for scab resistance. The preliminary observations on some of these seedlings are presented.     

QTLs for Fusarium head blight response in a wheat DH population of Wangshuibai/Alondra‘s’

Summary A doubled haploid (DH) wheat population derived from the cross Wangshuibai/Alondra‘s’ was developed through chromosome doubling of haploids generated by anther culture of hybrids. Fusarium head blight (FHB) was evaluated for three years from 2001 to 2003 in Jianyang, Fujian Province, China, where epidemics of FHB have been consistently severe. After 307 pairs of simple sequence repeat (SSR) primers were screened, 110 pairs were polymorphic between Wangshuibai and Alondra`s’, and used to construct a genetic linkage map for detection of quantitative trait loci (QTLs). A stable QTL for low FHB severity was detected on chromosomes 3B over all three years, and QTLs on chromosomes 5B, 2D, and 7A were detected over two years. Additional QTLs on chromosomes 3A, 3D, 4B, 5A, 5D, 6B and 7B showed marginal significance in only one year. Six QTLs were detected when phenotypic data from three years were combined. In addition, significant additive-by-additive epistasis was detected for a QTL on 6A although its additive effect was not significant. Additive effects (A) and additive-by-additive epistasis (AA) explained a major portion of the phenotypic variation (76.5%) for FHB response. Xgwm533-3B and Xgwm335-5B were the closest markers to QTLs, and have potential to be used as selectable markers for marker-assisted selection (MAS) in wheat breeding programs.     

小麦赤霉病抗源N553的主基因＋多基因遗传分析

运用主基因+多基因模型对N553的6家系抗赤霉病性遗传进行了分析,结果表明N553符合E-1-0(两对主基因+多基因的加性-显性-上位性)模型,其中第1对主基因的加性效应占明显优势,是第2对主基因加性效应的2倍,两对主基因具负向显性效应,上位性效应显著,多基因的互作效应明显;主基因的遗传率为25.71%~91.61%,多基因遗传率为3.15%~64.00%,环境对抗性的影响较小。     

小定额灌溉对‘黄冠’梨生长和果实品质的影响

为提高梨园水分利用率和梨果实品质,2016年3—11月在河北工程大学现代农业示范培训基地以4年生‘黄冠’梨为试材进行田间试验,研究小定额灌溉对梨园土壤含水量、梨树新梢生长量、产量与果实品质、根系分布与数量的影响。结果表明:不同小定额灌溉方式间灌溉区土壤含水量差异显著,沟灌土壤含水量显著高于树盘畦灌和滴灌,平均质量含水量为15.33%,其梨树的新梢生长量也为最大,达到42.25 cm;沟灌产量最高,单果重显著高于滴灌和树盘畦灌;沟灌果实维生素C含量显著高于滴灌和树盘畦灌,滴灌果实糖酸比显著大于沟灌和树盘畦灌,沟灌果实的可溶性固形物含量显著高于滴灌和树盘畦灌;沟灌处理下,梨树吸收根的数量显著高于树盘畦灌和滴灌,分别是它们的3.6倍和2.4倍。综合来看,沟灌是梨园最适宜的小定额灌溉方式。     

不同抗性花生品种接种疮痂病菌后其生理特性及产量的变化

为了研究不同抗性花生品种对疮痂病的抗性差异,在田间试验条件下,采用喷雾法研究抗病品种‘贺油13’、感病品种‘泉花10号’接种疮痂病菌后其叶片生理特性及产量的变化。结果表明：可溶性糖含量在接种后呈先升高后降低的趋势,抗病品种其可溶性糖含量均高于其对照,而感病品种与其对照相比均有所下降,说明花生叶片中可溶性糖含量与植株抗病性有一定的相关性。抗感花生品种接菌后叶片可溶性蛋白质含量均高于其对照,但感病品种比抗病品种的峰值出现的要早,表明感病品种对病菌的侵染较敏感,品种的抗病性与对病菌侵染的反应呈负相关。接菌后抗感品种叶片超氧化物歧化酶(SOD)活性均呈先升高后降低的变化趋势,与其相应的对照相比,抗病品种比感病品种降低的幅度相对较小;花生叶片过氧化氢酶(CAT)和过氧化物酶(POD)活性随生育进程的推进整体呈现先下降后升高再降低的变化趋势,其相应的对照相比,接种后抗病品种的CAT和POD活性表现相对较高,由此说明保护酶在花生对疮痂病的抗性机制中起了重要作用。接种后2个品种叶片丙二醛(MDA)含量有所增加,表明其质膜受到不同程度的伤害。产量结果研究表明,接菌后抗、感品种均有所减产,但感病品种‘泉花10号’减产幅度较大。