西宁地区的温室油桃品比试验

以“东方红”、“早大果”、“丽春”、“中油4号”、“中油5号”5个油桃品种为试材,通过对其物候期观测、果实品质测定、果实经济性状调查进行温室促早栽培品比试验.结果表明:果实成熟最早的是“东方红”,“丽春”、“中油5号”次之,“早大果”、“中油4号”最晚;从果实的品质指标来看,5个油桃品种可溶性糖、可滴定酸、维生素C、果实硬度、干物质含量均存在差异;从品种经济性状来看,5个油桃品种平均单果重、单位面积产量、裂果率、果形、果肉颜色差异显著;引进的5个油桃品种,在西宁地区的土壤和气候条件下进行温室促早栽培,均取得成功,并取得良好的经济效益,但综合评价,“东方红”、“丽春”、“中油5号”更具有市场前景.     

Development and variability analysis of microsatellite markers in peach

A genomic DNA library enriched with AG/CT repeats has been developed from the peach cultivar ‘Merrill O'Henry’. The enrichment method was efficient, with 61% of the clones obtained carrying a microsatellite sequence and a yield of one polymorphic microsatellite every 2.17 sequenced clones. From 35 microsatellites detected, 24 were polymorphic in a set of 25 cultivars including 14 peaches and 11 nectarines. A total of 82 alleles were found with the polymorphic microsatellites, with an average of a 37% of observed heterozygosity. Microsatellites with a high number of repeats were generally those having the largest number of alleles. All cultivars except two (‘Spring Lady’ and ‘Queencrest’) could be individually distinguished with the markers used. Just three selected microsatellites were enough for the discrimination of 24 out of the 25 possible genotypes. Cluster analysis grouped all nectarines in a single cluster. Peaches, with 75 of the 82 alleles found, were more variable than nectarines, with only 64. Microsatellites appear to be powerful and suitable markers for application in peach genetics and breeding.     

一氧化氮和外源乙烯处理对肥城桃果实乙烯生物合成的影响

 【目的】研究一氧化氮（NO）和乙烯处理对肥城桃内源乙烯生物合成的影响，并探讨NO与乙烯的拮抗作用。【方法】分别用10 μl•L-1 NO和1 000 μl•L-1 外源乙烯、10 μl•L-1 NO和1 000 μl•L-1 外源乙烯共同处理3种方式处理肥城桃果实，研究果实内源乙烯生物合成的变化。【结果】外源乙烯促进了肥城桃果实的内源乙烯生物合成；而NO通过显著降低果实中ACS和ACO的活性，明显抑制了肥城桃果实内源乙烯的生物合成。NO和外源乙烯共同处理的肥城桃果实内源乙烯生物合成低于外源乙烯单独处理而高于NO单独处理，表明NO对外源乙烯具有拮抗作用。【结论】NO抑制了果实内源乙烯的生物合成，且抑制了外源乙烯对果实乙烯生物合成的催化作用。     

桃树体内苦杏仁甙含量年变化研究

对桃(Prunus persica)树体内苦杏仁甙含量年变化的研究结果表明,叶片中苦杏仁甙含量为单峰曲线变化;一年生枝条韧皮部的苦杏仁甙含量在休眠期较高,而木质部的苦杏仁甙含量在休眠期较低;在旺盛生长期,韧皮部的苦杏仁甙含量较低,而木质部的苦杏仁甙含量较高;果肉及种仁的苦杏仁甙含量变化趋势相似,都呈上升趋势,5月中旬前果肉中苦杏仁甙含量高于种仁的苦杏仁甙含量,5月中旬之后相反,种仁的苦杏仁甙含量大于果肉中苦杏仁甙含量。     

Effects of exogenous cyanide on root physiology and metabolism of peach seedlings北大核心CSCD

【Objective】Peach (Prunus persica) is an economically important fruit crop worldwide. With the increasing demand and the reduced cultivated land acreage of peach, replant problem (also known as replant disease) has become increasingly prominent, and has been causing severe economic losses. Autotoxicity is a special kind of allelopathy, and is considered to be a major factor resulting in the prevalence of peach replant problem. Cyanide (CN-) is a major autotoxin that causes peach replant problem, but the information on physiological and metabolic responses of peach plants under CN- treatment is quite limited. Thus, the specific responsive mechanisms of peach plants to CN- are worthy of in-depth exploration. The study aimed to investigate the effects of CN- treatment on the morphological, physiological, and metabolic parameters in roots of peach seedlings, so as to provide new insights into the response mechanisms of peach plants to CN- treatment. 【Methods】The natural root environment of dead and living trees was investigated in the peach orchard of Huazhong Agricultural University. The effects of exogenous CN- treatment on root growth and seed germination were assessed on peach germinatedseeds (treated with 0, 0.25, 0.5, and 1.0 mmol•L-1 CN-) and lettuce seeds (treated with 0 and 0.5 mmol•L-1 CN- ). The peach root tips treated with 0 and 0.5 mmol • L-1 CN- were subjected to anatomical assessments using paraffin sectioning and staining (including transverse and longitudinal sections). The contents of H2O2 and MDA, as well as the activities of CAT, POD, and SOD from 0 and 0.5 mmol•L-1 CNstressed peach roots were detected. The expression levels of CAT, POD, and SOD-encoding genes were tested using qRT-PCR. To further understand the CN- -induced metabolic changes, peach roots treated with 0 and 0.5 mmol • L-1 CN- for 5 d were subjected to gas chromatography-mass spectrometry (GCMS) analysis. 【Results】The CN- was mainly distributed in 0-40 cm soil layer, and the content was significantly higher in the soil with dead trees than with living trees. The CN- content in soil was predominantly detected adjacent to peach roots, and gradually decreased with the distance from peach roots. The CN- contents showed an upward trend year by year in the bulk soils with the dead and living trees, where the dead trees contained more CN- than the living trees. The CN- contents varied in different size of peach roots, the fine roots (Φ < 5 mm) contained more CN- than the middle size (5 mm ≤ Φ ≤ 10 mm) and the large size roots (Φ > 10 mm). We evaluated the effect of different CN- concentrations (0, 0.25, 0.5, and 1.0 mmol•L-1) on the growth performance of peach germinated-seeds. The result showed that 0.25 mmol • L-1 CN- treatment boosted root growth, while 0.5 and 1.0 mmol • L-1 inhibited root growth with decreased root length and lateral root numbers. The allelopathy sensitivity index indicated that the effects of CN- treatment on peach growth in a concentration-dependent manner, showing low concentration promoted growth but high concentration inhibited it. Additionally, with 0.5 mmol•L-1 CNtreatment, the transverse and longitudinal sections of the root tip showed a severely wrinkled root epidermis, ruptured root cortex cells, and larger intercellular spaces. 0.5 mmol•L-1 CN- treatment also significantly inhibited lettuce seed germination and biomass. The contents of H2O2 and MDA in peach roots significantly increased, and the activities of SOD, POD, and CAT, as well as their respective encoding genes expression, significantly increased with 0.5 mmol•L-1 CN- treatment. The GC-MS analysis showed that 0.5 mmol • L-1CN- treatment dramatically increased contents of numerous amino acids, including proline, glycine, serine, asparagine, alanine, glutamate, GABA etc. Moreover, CN- treatment significantly affected carbohydrate levels in peach roots. 【Conclusion】The CN- contents were associated with the distribution and size of plant roots, and the decomposition of plant residuals. Exogenous CNsupply markedly retarded peach root growth. CN- feeding also gave rise to oxidative stress, reflecting by the increased ROS and MDA levels, and antioxidant enzyme activities. CN- supplementation also induced metabolic reprogramming, displaying a disorder of amino acid and carbohydrates metabolism. © 2022, Office of Journal of the Fruit Science. All right reserved.     

NITROGEN ABSORPTION AND RESPIRATION IN WHITE AND BROWN PEACH ROOTS

The relationship between root age and root physiology is poorly understood, despite its importance for nutrient absorption. In peaches, roots are white when they first appear and then become brown with age, which corresponds to a number of physiological changes. We related root browning to nitrogen (N) absorption and respiration in order to provide a better understanding of how color changes as typically observed using minirhizotrons relate to changes in root physiology. The experiment was conducted on peach seedlings (Prunus persica cv. ‘Guardian’) grown in 30-L pots in a greenhouse. Brown roots showed lower respiration rates than white roots. White roots showed a higher ¹⁵N uptake than brown roots and higher concentration of N, potassium (K), magnesium (Mg), manganese (Mn), iron (Fe) and copper (Cu), no significant differences were observed regarding calcium (Ca), and zinc (Zn) concentration.     

长柄扁桃产业发展潜势分析及问题对策研究

从长柄扁桃的开发利用优势出发,介绍了其种质资源分布的现状,探讨了发展区域的拓展潜力,并提出了加快其发展的技术、政策等方面的相应对策,为今后加快长梗扁桃产业发展提供了可靠的理论依据。     

蜡蚧轮枝菌对桃蚜的室内毒力测定研究

[目的]筛选对桃蚜侵染致病力强的蜡蚧轮枝菌菌株,为该菌的进一步开发利用奠定基础.[方法]采用波特喷雾塔测定法,测定来源于俄罗斯的6株蜡蚧轮枝菌菌株对桃蚜的侵染致死情况.[结果]高浓度处理（＞1×106孢子/ml）,多数菌株在第5、6天达到死亡高峰;第7天结束观察时,所测定各菌株的最高浓度处理（1×108孢子/ml）若蚜校正死亡率均达到95％以上.V3、V4菌株在该浓度下致死中时间分别为4.25和4.11 d.[结论]参试菌株对桃蚜均表现出较高的致病性,V3、V4菌株为更优良的备用菌株.     

Fruit Quality and Flavor Compounds Before and After Commercial Harvest of the Late-Ripening ‘Fairtime’ Peach Cultivar

ABSTRACT

In this work quality of tree ripe and commercial ripe ‘Fairtime’ peach fruit was evaluated during fruit maturation and storage. Quality parameters and volatile fraction were monitored at intervals of 7-15 days from pit hardening until 10 days after commercial harvest and after 7, 17 and 24 days of refrigeration. In fruit on the tree, weight increased quadratically, diameter and peel color increased linearly, whereas flesh firmness decreased linearly. Soluble solids (SS) reached maximum levels at commercial harvest, whereas acidity started declining after commercial harvest. In the peel, esters and alcohols showed opposite trends. In the flesh, alcohols decreased quadratically and disappeared in tree ripe fruit. In refrigerated fruit, there were no significant weight changes, flesh firmness decreased linearly, SS reached a minimum around the 10th day, and acidity decreased quadratically. A three day harvest delay followed by two weeks of refrigeration may represent a chance to further extend marketing of optimum flavor ‘Fairtime’ peaches into late fall.     

新疆野扁桃与其近缘种的亲缘关系

野扁桃（Amygdalus ledebouriana Schlecht）为野生珍稀濒危植物资源,我国仅分布在新疆。为研究野扁桃与栽培扁桃及其近缘种的亲缘关系,对新疆野扁桃、栽培扁桃、栽培桃和桃属部分物种的叶绿体matK基因进行测序,基于Kimura 双参数模型计算种间遗传距离,并以邻接法（NJ）构建系统发育树。结果表明：野扁桃与蒙古扁桃和榆叶梅的遗传距离较小,与栽培扁桃和桃属物种（桃、山桃和蟠桃）的遗传距离较大;栽培扁桃与山桃、蟠桃和桃的亲缘关系较其与野扁桃、榆叶梅和蒙古扁桃的亲缘关系更近。