‘21世纪’桃对其砧木毛桃根系导管分子性状的影响

 采用组织离析法和显微照相技术,观测了以毛桃为砧木,‘21世纪’桃品种为接穗的嫁接树与非嫁接树根系导管分子类型和大小。结果表明：与未嫁接的实生砧木树相比,嫁接树的根系中导管分子侧壁次生增厚和木质化的方式、纹孔式及穿孔板类型未见变化,但两端具尾的导管分子数明显减少,导管分子端壁向一端壁水平一端壁倾斜的中间类型变化,导管分子长度变化不大,但直径明显变小。这意味着桃树接穗对砧木根系导管分子的类型与直径产生了一定的影响。     

桃,苹果枝条次生木质部细胞的角离研究

在扫描电镜下，观察到５个桃品种和２个苹果品种枝条的次生木质部解度后扭管细胞，桃为螺纹导管型，苹果为孔纹导管型；两者的导管细胞上均有多层和几种形式的次生加厚。     

桃、苹果枝条次生木质部细胞的解离研究

在扫描电镜下,观察到5个桃品种和2个苹果品种枝条的次生木质部解离后的导管细胞,桃为螺纹导管型,苹果为孔纹导管型;两者的导管细胞上均有多层和几种形式的次生加厚.对上述品种导管及纤维细胞的长度、直径在光镜下进行了统计、比较,结果表明,桃导管细胞长度在303.1—328.7μm之间,直径在26.2—35.lμm之间;苹果在392.2—407.0μm和37,4—37.9μm之间,桃与苹果表现了极显著差异,桃导管细胞明显小于苹果.揭示了桃较苹果生长弱、树冠矮小的生理原因,为研究果树抗性生理和果树分类提供了细胞解剖学依据.     

21世纪桃树次生木质部导管分子特征的观察

运用离析法和显微照相等技术,以晚熟桃21世纪桃为试材、典型的耐寒品种珲春桃为对照,研究比较了21世纪桃次生木质部导管分子的特征。结果表明,21世纪桃树干次生木质部导管分子中存在着许多不同的样式,迎风面导管分子的特征为多具尾性、长导管性、宽导管性、孔纹导管、单穿孔等,这些特征为21世纪桃在生长季节旺盛的水分需求提供了强有力的保证作用,同时,在风力强劲的冬季也可能使导管容易形成空穴和栓塞,水力结构破坏,致使输水系统受限,可能造成冬害。     

菠萝蜜次生木质部导管分子观察

运用计算机显微图象分析系统(北京泰克4.0)及显微照相的方法对菠萝蜜Artocarpusheterophyllus次生木质部导管分子进行了观察研究。研究表明,在菠萝蜜次生木质部导管分子中存在着许多不同的样式,分别对其进行了描述。导管分子具有如下特征:圆形宽大的导管、巨大的单穿孔、侧壁上大型的单纹孔等。这些特征为菠萝蜜生长过程中水分的需求提供了强有力的保证作用。并从导管分子个体发育与系统发育的角度进行了讨论。     

梨树和桃树新梢次生木质部细胞解离的比较研究

采用Joffrey氏离析法[1]对梨和桃各3个品种新梢次生木质部细胞解离,在扫描电镜下,清晰观察到梨各品种新梢次生木质部导管细胞为孔纹导管类型,而桃为螺纹导管类型;在光镜下观察了供试各品种的导管、管胞、纤维细胞的长度和直径。结果表明:梨的导管细胞长度为429.9～440.4μm,直径为29.9～31.6μm,而桃则为303.1～316.7μm和26.2～35.1μm。梨与桃表现了极显著差异;管胞和纤维细胞长度和直径也表现了显著和极显著差异。     

苹果不同砧木枝条导管分子特征参数比较

以苹果矮化砧木M27、M9、M26、MM106及乔化砧木八棱海棠的一年生枝条为试材,采用组织离析法,研究了苹果不同砧木导管分子在光学显微镜和扫描电镜下形态特征参数,以期为探索苹果矮化砧木致矮机理提供依据。结果表明:八棱海棠与M系砧木导管分子均为孔纹导管;八棱海棠导管分子在长度和尾长上均显著高于M系砧木;M系砧木导管分子宽度、纹孔式、纹孔膜残留、端壁倾斜角与八棱海棠无明显差异。以上结果表明,矮化砧木较乔化砧木具有短导管性、短尾性,这种特性可能是矮化砧木致使树体矮化的原因之一。     

人心果次生木质部导管分子的观察研究

 运用细胞图象分析系统及显微照相的方法, 观察研究人心果次生木质部导管分子。结果发现,人心果次生木质部导管分子中存在着许多不同的样式, 多数导管分子具尾; 导管分子穿孔板存在着两种类型: 1. 两端均为一个单穿孔板; 2. 一端为一个单穿孔板另一端为两个单穿孔板及过渡类型; 3%的导管分子具有内含物; 管间纹孔式为互列纹孔式, 导管射线间纹孔式为混合型纹孔与横列刻痕状纹孔以及穿孔。     

沙棘枝条次生木质部的细胞解剖学研究

采用Joffer氏离析法，对沙棘新梢次生木质部进行解离，并在光学显微镜下观察。结果表明：沙棘枝条次生木质部导管细胞为孔纹导管，经对沙棘与红星苹果枝条的细胞大小比较，沙棘导管的长度和直径均极显著地小于红星苹果，且沙棘的畸形导管明显多于红星苹果；沙棘导管次生壁较红星苹果加厚明显；沙棘的管胞、纤维细胞的长度和直径也较红星苹果小，差异达极显著水平。     

Phenotyping vigour control capacity of new peach rootstocks by xylem vessel analysis

In peach, xylem anatomical characteristics have been shown to be related to vigour of selected rootstocks. The goal of this research was to determine if xylem characteristics of a new set of rootstocks that exhibit a range of size-controlling potential and have a different genetic background from previously examined material would also exhibit similar differences in xylem characteristics. If so, then anatomical analysis of xylem may be a useful means of predicting the vigour control capacity of selected peach rootstock genotypes. Samples of xylem tissue were taken from roots, trunks and shoots of four new rootstocks that were derived from a genetic cross between ‘Harrow Blood’ and ‘Okinawa’ peaches and compared with tissue from ‘Nemaguard’, a vigorous control. Xylem samples were sectioned and analysed by optical microscope. The number and dimensions of vessels in recently developed xylem of each rootstock were measured and compared. The more dwarfing rootstocks had fewer large vessels and more small vessels than the more vigorous rootstocks. Weighted mean vessel diameter (Wm) and calculated hydraulic conductance (K_h) differed among rootstocks: more vigorous rootstocks had higher K_h and Wm than dwarfing rootstocks. Rootstock xylem vessel dimensions varied in relation to the vigour they imparted to a common scion cultivar (‘O’Henry’). After the ‘Nemaguard’ control, ‘HBOK 50’ was the most vigorous rootstock followed by ‘HBOK 10’, ‘HBOK 32’ and ‘HBOK 27’, respectively. Thus, as was seen in previous research with a separate set of rootstocks, the vigour-control capacity of this new series of peach rootstocks was strongly related to their xylem hydraulic characteristics and it appears likely that it would be possible to use xylem anatomical characteristics of shoots or roots of young trees to pre-select for size-controlling potential in a rootstock development program.     

Performance of peach and plum based rootstocks of different vigour on a late peach cultivar in replant and calcareous conditions

The field performance of fifteen peach and plum based rootstocks of different vigour (Adesoto, Evrica, Garnem, GF 677, HM-2, Krymsk^® 1, PAC 9801-02, PAC 960, PAC 9907-02, PAC 9917-26, PAC-MUT, PADAC 9907-23, ROOTPAC^® 40, ROOTPAC^® 70 and Tetra) grafted with ‘Calrico’ cultivar was compared after 7 years of establishment on an Armillaria infested replant site. ‘Calrico’ is a selected clone of “Calanda” late peach cultivar. Differences in parameters such as tree survival, leaf chlorophyll content, vigour, yield, cumulative yield, yield efficiency and fruit size were analyzed among rootstocks. All PAC 9801-02 and Tetra trees survived and the mortality rate was low in Evrica, PADAC 9907-23 and ROOTPAC^® 40. The rest of genotypes showed higher mortality rates. Leaf chlorophyll concentration was higher when grafted on Adesoto and Evrica and lower when grafted on PAC 9907-02 and PAC 9917-26. Garnem and PADAC 9907-23 were the most vigorous rootstocks. The highest yield efficiency was induced by Krymsk^® 1 and PAC 9801-02 due to their lower vigour. The highest fruit weight was also induced by Krymsk^® 1 but its cumulative yield was low. Other rootstocks that showed high fruit weight and cumulative yields were ROOTPAC^® 70 and Tetra. Overall, Evrica, PAC 9801-02, ROOTPAC^® 40 and Tetra were among the best adapted to soil sickness and calcareous soil showing a good agronomic performance. The first three rootstocks (Evrica, PAC 9801-02, ROOTPAC^® 40) also exhibited a high capacity to control tree vigour associated with high yield efficiency.     

不同组合桃杂交后代(F_1)群体幼苗光合特性比较

为探求桃光合性能的遗传规律,筛选高光效杂交组合,分别于7月中旬和9月下旬测定了8个组合桃杂交后代(F1)群体幼苗的光合特性。结果表明,叶绿素含量(Chl)与类胡萝卜素含量(Car)极显著正相关,CO2饱和净光合速率(CSPn)与羧化效率(CE)显著正相关,饱和光强净光合速率(LSPn)与CE负相关。净光合速率(Pn)对CO2浓度(Ca)响应曲线的相关性状变异程度较大,蕴藏着较大的选择潜力。     

桃不同类型果实发育的解剖结构特性

为探讨普通桃、油桃、蟠桃和油蟠桃果实发育期表皮、亚表皮和中果皮细胞的解剖结构差异,试验以同一杂交群体内的这4种类型(各2株)为试材,通过显微和超微观察果实表皮、亚表皮和中果皮细胞发育。结果表明,4种类型果实的横径发育皆呈双S曲线,果实亚表皮细胞前期变化较小,开始膨大期为盛花后42d。普通桃、油桃和油蟠桃中果皮细胞在整个果实发育期持续膨大,类型间变化趋势基本一致,而蟠桃中果皮细胞在盛花后70～84d存在膨大延缓期。盛花后42～98d,普通桃和蟠桃亚表皮与中果皮细胞膨大倍数之比大于油桃和油蟠桃。分析认为,果实有毛/无毛基因单独影响着表皮细胞形状和亚表皮与中果皮细胞膨大倍数之比,而无毛基因与扁平基因共同影响着亚表皮淀粉粒数目,并且这种作用有累加现象。     

桃幼树光合年变化及落叶期早晚与营养生长的关系

试验以2个桃品种(南方早红和大久保)1 a生幼树为试材,研究了光合年变化和落叶期早晚与营养生长的关系。结果表明,2个品种桃6月份光合速率日变化呈双峰曲线,最高峰在11:00,次峰在14:00—15:00;8月份光合速率曲线呈单峰,最高峰在13:00。日光合总量的季节变化也呈双峰,分别在5月和8月。4—8月南方早红单位面积月光合总量占年总量的94.15%,大于大久保同时期的比值。南方早红落叶晚于大久保,且抽生新梢能力强于大久保。因而,南方早红9—10月光合面积的增大对单株年光合总量增加的贡献略高于大久保。实验认为,南方早红4—8月高的光合能力和9—10月落叶期晚对其旺盛的营养生长都具有重要的促进作用。     

桃果实白肉/黄肉性状的RAPD标记向SCAR标记的转化研究

以桃品种京玉和美味的正反交69株F1群体为试材,利用RAPD技术扩增出了与桃果实白肉/黄肉性状连锁的899bp的多态性片段,经克隆、测序后,根据获得的序列重新设计了一对引物进行SCAR转化。利用引物对BFP15/60成功将RAPD标记转化成了SCAR标记,并命名为SCU03-900。该标记仅在果肉为白肉的个体和重组型个体中出现,与白肉/黄肉性状的连锁距离为21cM,且扩增稳定,为桃果实白肉/黄肉性状育种的分子标记辅助选择奠定了基础。     

25%戊唑醇水乳剂田间防治桃穿孔病试验初报

通过对桃穿孔病2年的田间防治试验,结果表明,25%戊唑醇水乳剂是防治桃叶穿孔病的有效杀菌剂,田间使用浓度以1500倍液和2000倍为宜。