A study of the soil water potential threshold values to trigger irrigation of ‘Shimizu Hakuto’ peach at pivotal fruit developmental stages

Water management is an important practice that affects fruit size and quality.Effective implementation of irrigation scheduling requires knowledge of the appropriate indicators and thresholds,which are established manly based on the effects of water deficits on final fruit quality.Few studies have focused on the real-time effects of water status on fruit and shoot growth.To establish soil water potential (ψ_(soil)) thresholds to trigger irrigation of peach at pivotal fruit developmental stages,photogrammetry,^(13)C labelling,and other techniques were used in this study to investigate real-time changes in stem diameter,fruit projected area,net leaf photosynthetic rate (P_(n)),and allocation of photoassimilates to fruit under soil water potential conditions ranging from saturation to stress in 6-year-old Shimizu hakuto’peach.Stem growth,fruit growth,and P_n exhibited gradually decreasing sensitivity to water deficits during fruit developmental stages I,II,and III.Stem diameter growth was significantly inhibited whenψ_(soil)dropped to-8.5,-7.6,and-5.4 k Pa,respectively.Fruit growth rate was low,reaching zero when theψ_(soil)was-9.0 to-23.1,-14.9 to-21.4,and-16.5 to-23.3 k Pa,respectively,and P_ndecreased significantly when theψ_(soil)reached-24.2,-22.7,and-20.4 kPa,respectively.In addition,more photoassimilates were allocated to fruit under moderateψ_(soil)conditions (-10.1 to-17.0 k Pa) than under otherψ_(soil)values.Our results revealed threeψ_(soil)thresholds,-10.0,-15.0,and-15.0 kPa,suitable for triggering irrigation during stages I,II,and III,respectively.These thresholds can be helpful for controlling excessive tree vigor,maintaining rapid fruit growth and leaf photosynthesis,and promoting the allocation of more photoassimilates to fruit.

Genomic analysis provides insights into the westward expansion of domesticated peaches in China

Peach, an economically important model plant of the Rosaceae family, has been domesticated and cultivated in China for approximately5 000 years. The Hexi Corridor, an important corridor connecting east-central China and the Tarim Basin, is the starting point of the Silk Road that links China and the Eurasian region. As a globally distributed fruit tree, the spread of peach was accomplished through historical trade routes in the Hexi Corridor and the Tarim Basin. However, knowledge of peach genetic diversity in these regions remains limited. In this study,we examined the relationships and the spread history of domesticated peaches through sequencing and genomic analysis of 161 peach accessions collected from Northwest China, including 43 from the Hexi Corridor and 104 from the Tarim Basin. The results indicate that peach landraces in the Hexi Corridor and the Tarim Basin are derivatives of peaches from the east and south of China (ESC). Notably, the genetic diversity of accessions from both the Hexi Corridor and the Tarim Basin was lower than that of ESC accessions. Reduction of diversity (ROD) and linkage disequilibrium (LD) analyses detected a genetic bottleneck in peaches from these regions. Additionally, these peaches have undergone varying degrees of selection from natural environment. Moreover, genes responsive to biotic and abiotic stresses were under selection, which could be the result of the climate change of Northwest China after the Last Glacial Maximum (LGM). Our findings provide a better understanding of the genetic basis of peach migration in Northwest China. Furthermore, this study expands the available genomic data for peaches and provides critical information for future peach breeding programs.

Peculiarity of transcriptional and H3K27me3 dynamics during peach bud dormancy

Bud dormancy facilitates the survival of meristems under harsh environmental conditions.To elucidate how molecular responses to chilling accumulation controlling dormancy in peach buds,chromatin immunoprecipitation sequencing to identify the H3K27me3 modifications and RNA sequencing of two peach cultivars with pronounced differences in chilling requirement were carried out,the results showed that genes associated with abscisic acid and gibberellic acid signal pathways play key roles in dormancy regulation.The results demonstrated that peach flower bud differentiation occurred continuously in both cultivars during chilling accumulation,which was correlated with the transcript abundance of key genes involved in phytohormone metabolism and flower bud development under adverse conditions.The more increased strength in high chillingrequirement cultivar along with the chilling accumulation at the genome-wide level.The function of the dormancy-associated MADS-box gene PpDAM6 was identified,which is involved in leaf bud break in peach and flower development in transgenic Nicotiana tabacum(NC89).In addition,PpDAM6 was positively regulated by PpCBF,and the genes of putative dormancy-related and associated with metabolic pathways were proposed.Taken together,these results constituted a theoretical basis for elucidating the regulation of peach bud dormancy transition.

Study on Germplasm Resources of Peach Cultivars

[Objectives]To study the germplasm resources of excellent peach cultivars.[Methods]Five peach cultivars were introduced,in-cluding‘Jinxiu’peach,‘Jinxiang’peach,‘Chunxiao’peach,‘Hujingmilu’peach and‘018 nectarine’peach.Then,these five cultivars were used to study the biological characteristics of peach trees,namely,as phenology,fruit quality,heat resistance,cold resistance and other resistance.[Results]Five cultivars of peach plants grew fast and robust,among which‘018 nectarine’had very crisp fruit,‘Jinxiu’,‘Jinxiang’,‘Chunxiao’and‘Hujingmilu’had very sweet fruitꎻthe peach trees of these five cultivars have good water resistance,heat resist-ance and cold resistance.[Conclusions]The results of this study can not only provide a reference for the introduction of peach trees,but also provide a practical basis for the large-scale planting of peach trees.

Evaluation of Trace Elements in the Soil of Typical Peach Orchards in Zunyi City

[Objectives]This study was conducted to clarify the enrichment and paucity of trace elements in the soil environment of peach orchards in Zunyi City,and to provide reference for supplementary application of microelement fertilizers and high-quality peach production in peach orchards.[Methods]Taking the soil of three typical peach orchards(Taoli Renjia peach orchard,Pengrui peach orchard and Taohuadao peach orchard)in Shenxi Town,Honghuagang District,Zunyi City as the research object,the contents of trace elements in soil were analyzed through field sampling and indoor determination of trace elements.[Results]The effective contents of trace elements in the soil of peach orchard bases in the study area were at a medium level,and the soil of the peach orchards was rich in available Fe and Se.The contents of available Cu,Mo and Mn were relatively rich.The contents of available B were not high overall.The contents of available Zn were at a moderate to low level overall.The soil of Taoli Renjia peach orchard was relatively rich in trace elements.[Conclusions]The research results can provide a scientific basis for the production of high-quality crispy peaches in peach orchards.

Color of the Year 2024: Peach Fuzz

Pantone has declared Pantone 13-1023Peach Fuzz as its Color of the Year for 2024.This soft peach tone reflects comforting warmth and represents a desire for unity,peace and personal well-being.The calming shade,a sublime blend of pink and orange,suggests fresh softness,signifying an environment that invites relaxation,reccovery and growth.The delicatehue of Pantone 13-1023 Peach Fuzz not only awakens our senses to the tactile and enveloping warmth of the color,but also influences our sense of peace and overall well-being.

Genome sequencing revealed the red-flower trait candidate gene of a peach landrace

Peach(Prunus persica)is an economically important fruit crop globally and an excellent material for genomic studies.While considerable progress has been made in unveiling trait-associated genes within cultivars and wild relatives,certain novel genes controlling valuable traits in peach landraces,such as the red-flowering gene,remained unclear.In this study,we sequenced and assembled the diploid genome of the red-flower landrace‘Yingzui’(abbreviated as‘RedY’).Multi-omics profiling of red petals of‘RedY’revealed the intensified red coloration associated with anthocyanins accumulation and concurrent decline in f lavonols.This phenomenon is likely attributed to a natural variant of Flavonol Synthase(FLS)harboring a 9-bp exonic insertion.Intriguingly,the homozygous allelic configurations of this FLS variant were only observed in red-flowered peaches.Furthermore,the 9-bp sequence variation tightly associated with pink/red petal color in genome-wide association studies(GWAS)of collected peach germplasm resources.Functional analyses of the FLS variant,purified from procaryotic expression system,demonstrated its diminished enzymatic activity in f lavonols biosynthesis,impeccably aligning with the cardinal trait of red flowers.Therefore,the natural FLS variant was proposed as the best candidate gene for red-f lowering trait in peach.The pioneering unveiling of the red-flowered peach genome,coupled with the identification of the candidate gene,expanded the knowledge boundaries of the genetic basis of peach traits and provided valuable insights for future peach breeding efforts.

PpMAPK6 regulates peach bud endodormancy release through interactions with PpDAM6

The MADS-box(DAM)gene PpDAM6,which is related to dormancy,plays a key role in bud endodormancy release,and the expression of PpDAM6 decreases during endodormancy release.However,the interaction network that governs its regulation of the endodormancy release of flower buds in peach remains unclear.In this study,we used yeast two-hybrid(Y2H)assays to identify a mitogen-activated protein kinase,PpMAPK6,that interacts with PpDAM6 in a peach dormancy-associated SSHcDNA library.PpMAPK6 is primarily located in the nucleus,and Y2H and bimolecular fluorescence complementation(BiFC)assays verified that PpMAPK6 interacts with PpDAM6 by binding to the MADS-box domain of PpDAM6.Quantitative real-time PCR(qRT-PCR)analysis showed that the expression of PpMAPK6 was opposite that of PpDAM6 in the endodormancy release of three cultivars with different chilling requirements(Prunus persica‘Chunjie’,Prunus persica var.nectarina‘Zhongyou 5’,Prunus persica‘Qingzhou peach’).In addition,abscisic acid(ABA)inhibited the expression of PpMAPK6 and promoted the expression of PpDAM6 in flower buds.The results indicated that PpMAPK6 might phosphorylate PpDAM6 to accelerate its degradation by interacting with PpDAM6.The expression of PpMAPK6 increased with decreasing ABA content during endodormancy release in peach flower buds,which in turn decreased the expression of PpDAM6 and promoted endodormancy release.

β-Cyclodextrin-Based Nitrosoglutathione Improves the Storage Quality of Peach by Regulating the Metabolism of Endogenous Nitric Oxide, Hydrogen Sulfide, and Phenylpropane

Nitrosoglutathione(GSNO)andβ-cyclodextrin(β-CD)exhibit positive roles in regulating fruit quality.However,there are few reports about the effects of GSNO andβ-CD on enhancing storability and boosting nitric oxide(NO),hydrogen sulfide(H2S),and phenylpropane metabolism in fruits during storage.“Xintaihong”peach were treated with 0.5,1.0,1.5mmol L−1 GSNO in 0.5%(w/v)β-CD solution(GSNO/β-CD).The effects of GSNO/β-CD on endogenous NO,H2S,and phenylpropane metabolism were investigated.Treatment with GSNO/β-CD increased the color difference of peach and inhibited the increase of respiratory intensity,weight loss,and relative conductivity.Treatment with 1.0 mmol L−1 GSNO/β-CD increased the nitric oxide synthase(NOS-like)activity and L-arginine content,thereby promoting the accumulation of endogenous NO.By improving the activities of L-cysteine desulfhydrylase(L-CD),O-acetylserine sulfur lyase(OAS-TL),serine acetyltransferase(SAT),GSNO/β-CD increased the content of endogenous H2S in peach.Treatment with GSNO/β-CD increased the activities of phenylalanine ammonia-lyase(PAL),4-coumarate-CoA ligase(4CL),and cinnamic acid-4-hydroxylase(C4H),promoted the increase of total phenols,flavonoids,and lignin in peach.These results indicated that GSNO/β-CD treatment better maintained the quality of peach by improving the metabolism of endogenous NO,H2S,and phenylpropane during storage.

The Potential Efficacy of Glycyrrhizic Acid and Its Nanostructure Against Brown Rot of Peach fruits

Production of peaches(Prunus persica(L.)Batsch)for both local market and export is increasing each year in Egypt.Brown rot disease,caused by Monilinia laxa and Monilinia fructigena,is considered one of the most important postharvest rots affecting peaches in Egypt and economic losses are increasing.Antifungal activity of glycyrrhizic acid nanoparticles(GA-NPs)and glycyrrhizic acid(GA)at 0.2 and 0.4 mmol/L was investigated as a control for both these brown rot pathogens on peach fruits in both in vitro and in vivo studies.In the in vitro studies,GA-NPs were the most effective as shown by the ability to decrease linear growth of both brown rot pathogens in potato dextrose agar(PDA)amended with 0.4 mmol/L GA-NPs.Micrographs of M.fructigena exposed to 0.4 mmol/LGA showed mycelial deformations,nodule formation,detachment of the cell wall,shrinkage and inhomogeneous cytoplasmic materials with large vacuoles.Mycelium of M.laxa exposed to 0.4 mmol/LGA-NPs resulted in thinner and distorted hyphae,nodule formation,cell wall thinning,and swellings.The GANPs and GA treatments improved fruit quality by maintaining firmness and total soluble solids(TSS).GA-NPs were more effective in decreasing decay incidence than their bulk material.The 0.4 mmol/L GA-NPs completely inhibited the disease on naturally infected peach fruits for both seasons of 2018 and 2019.Furthermore,0.4 mmol/L GA-NPs reduced the disease incidence in inoculated fruits by 95(M.laxa)and 88%(M.fructigena)in 2018 season and 96(M.laxa)and 85%(M.fructigena)in 2019 season.In conclusion,GA-NPs could enhance the resistance of peaches against brown rot caused by M.laxa and M.fructigena.

Identification of Early Peach Aphid Infestation Based on Hyperspectral Imaging Technology

Peach aphid is a common pest and hard to detect.This study employs hyperspectral imaging technology to identify early damage in green cabbage caused by peach aphid.Through principal component transformation and multiple linear regression analysis,the correlation relation between spectral characteristics and infestation stage is analyzed.Then,four characteristic wavelength selection methods are compared and optimal characteristic wavelengths subset is determined to be input for modelling.One linear algorithm and two nonlinear modelling algorithms are compared.Finally,support vector machine(SVM)model based on the characteristic wavelengths selected by multi-cluster feature selection(MCFS)acquires the highest identification accuracy,which is 98.97%.These results indicate that hyperspectral imaging technology have the ability to identify early peach aphid infestation stages on green cabbages.

Evaluation on Soil Improvement Effects of Organic Fertilization in Honey Peach Orchard in the Longquan Mountain

Combined application of organic fertilizer is an effective measure to improve the productivity and ecological effect of newly added soil.However,the effect of organic fertilizer application in newly added orchard soil is not clear.In this project,the soil of newly built peach orchard in the Longquan Mountain of Chengdu was applied with 45 t/hm 2 of organic fertilizer.After 9 months of planting 6 varieties of honey peach(Wanhujing,Baifeng,Zhongtao 13,Huangjinmitao 1,Zhongpan 101,Zhongpan 104),the locally well developed peach orchard was taken as the control.The physical and chemical properties of soil from four topography(top slope,middle slope,lower slope and flat land)of newly built peach orchard were analyzed,and the effect of organic fertilizer on soil was evaluated.The results showed that combined application of organic fertilizer had different effects on soils from orchards with different varieties of peach and from different terrain parts of the same peach variety.Specifically,it had the best effect on soil improvement in Baifeng(local variety),Zhongpan 101 and Zhongpan 104(introduced varieties).Meanwhile,the best effect of soil improvement was found on top slope.Cluster analysis divided newly built peach orchards,uncultivated soil,and locally well developed peach orchard into four groups,indicating that the selected amount of organic fertilizer application in this study has improved the soil of peach orchards to some extent,but it was still necessary to increase the application amount.It was better for 54 t/hm 2 amount of organic fertilization on the part of top and middle slope,and 60 t/hm 2 on the lower slope and flat land.The comprehensive ecological benefit assessment of organic fertilizer should be conducted based on long-term monitoring of peach orchard ecological environment,fruit tree growth,fruit yield and quality,which would provide scientific basis for peach orchard production and management.

氮肥和缩节胺对棉花纤维产量及品质时间分布的影响

棉花伏前桃、伏桃、早秋桃和晚秋桃(“四桃”)的时空分布不同,但目前“四桃”的纤维产量和品质差异及其对氮(N)肥与缩节胺(DPC)配施的响应鲜见报道。2015—2017年,在郑州市黄河滩区采用双因素裂区设计,以3个N肥用量为主区,即不施N肥(N0)、常量施N(N1)和过量施N(N2),用量分别为0、225和450 kg hm-2;以3个DPC用量为副区,即不喷施DPC(D0)、常量DPC(D1)和过量DPC(D2),用量分别为0、75和150 g hm-2。研究了N肥与DPC配施对棉花纤维产量及品质时间分布的影响。结果表明,(1)N1处理的“四桃”纤维产量比N0和N2处理分别增加36.79%和3.27%, N2处理减产不显著;D1处理比D0和D2处理分别增产17.53%和8.50%, D2处理减产达到显著水平;N1D1组合产量最高,其余组合减产1.15%~51.53%。N1D1组合的伏前桃、伏桃、早秋桃和晚秋桃产量分别占8.89%、45.35%、33.41%和12.36%,伏桃和早秋桃是产量主体,但早秋桃的成产强度大。随着施N量增加,早秋桃和晚秋桃的纤维产量占比增加,而随着DPC用量增加则表现相反。(2) N肥用量和DPC用量均对纤维长度、整齐度、比强度和马克隆值有显著影响,但对纤维伸长率影响达不到显著水平。N1处理和D1处理的纤维品质综合表现最优,但D0处理马克隆值最佳。N肥与DPC用量互作对“四桃”的纤维比强度和马克隆值有显著影响,其中, N1D1处理“四桃”的比强度和马克隆值均表现最优,而N2D2处理“四桃”的比强度和马克隆值表现最差。此外,过量施N和过量喷施DPC均会升高马克隆值。(3)“四桃”的纤维品质存在差异。伏前桃的纤维品质除马克隆值最优外,其纤维长度、整齐度和比强度最差;伏桃和早秋桃的纤维长度、整齐度和比强度最优,但马克隆值表现最差,伸长率居中;晚秋桃的伸长率最优,其余品质指标均居中。研究结果丰富了“四桃”产量和品质差异的相关理论,并为棉花合理施N和喷施DPC以及“四桃”纤维的合理利用提供了科学依据。

中晚熟蟠桃新品种中蟠104的选育

中蟠104是通过多代人工杂交聚合选育的中晚熟黄肉蟠桃新品种,其母本为晚熟黄肉桃优系‘06-3-137’,父本为早熟黄肉蟠桃优株‘07北5-60’。花为蔷薇型,粉红色花瓣,花瓣数5片,花粉多,自花结实,丰产稳产。在郑州地区果实8月上旬成熟,果实生育期137 d左右。单果质量241 g,果实扁平,果顶闭合性好;果皮茸毛短,底色黄色,果面全红;套袋后果面全黄;果肉黄色,硬溶质,黏核;肉质细腻,可溶性固形物含量(w)15.2%,风味甜香。

不同类型果袋对蟠桃果实品质的影响

为了明确蟠桃果实优质生产的果袋类型,以金霞油蟠和瑞油蟠2号2个蟠桃品种为试验材料,6月上旬分别选用外黄内黑双层袋、白色单层袋进行果实套袋处理,以不套袋处理为对照,研究了不同类型果袋对蟠桃果实外观品质和内在品质的影响。结果表明:与未套袋的对照相比,2个蟠桃品种果实套袋后单果重和可食率明显增大,成熟期果面黄色度增加、红色度降低,果面亮度和光洁度有效提高,果皮擦伤度和果实裂果率明显降低,带皮硬度、去皮硬度和可溶性固形物含量降低不显著,其中套外黄内黑双层袋的效果优于套白色单层袋。外黄内黑双层袋对提高蟠桃果实外观品质和内在品质的效果优于白色单层袋,研究结果可为今后生产实践中提高蟠桃果实品质,尤其是解决蟠桃裂果问题提供理论参考。

7个桃品种不同时期硬枝扦插生根效果试验

为探索不同桃品种扦插成活的最佳时期,为桂北优质桃品种的大量扦插繁殖提供技术保障,以“农神蟠、春艳、沙红、中华福桃、日本大红桃、梦幻富士、四月红”等7个桃品种为材料,在10、11、12月和次年1月分别进行硬枝扦插。结果表明:“农神蟠、春艳、沙红、红富士”4个桃品种在11月的扦插生根率最高,中华福桃和日本大红桃在10月的扦插生根率最高,而四月红在4个扦插时期的生根率无显著差异。进一步基于生根率、根数、根长、根粗采用隶属函数法对桃各品种的生根效果进行综合评价,评价指数表明,同一扦插时期不同品种间的生根效果有所差别,而同一品种在不同扦插时期的生根效果亦有较大差异,但各品种最佳生根时期均为11月。研究结果可为不同桃品种大量扦插繁殖提供科学依据,对大面积推广种植具有实际指导意义。

桃采后品质劣变生物学及调控技术研究进展

桃常温放置易腐烂变质,长期的低温冷藏易导致果肉褐变、风味丧失、抗病性降低、有害物质积累等,是桃产业链的关键性采后问题。前人研究表明,采后品质劣变症状及相关代谢酶、蛋白、基因对果实衰老和调控技术表现出应答差异性,为了解研究概况,笔者对采后品质劣变生物学、调控技术、技术和产品的产业化应用等方面的研究进展进行归纳和分析。目前,采后品质劣变生物学主要局限于质地、内在品质和冷害及相关基因的挖掘和验证,调控技术虽然被广泛研究,但仍未解决长期冷藏导致的果实抗病性降低、风味丧失和货架期缩短的问题。建议后续基于多组学技术,从超微结构、糖和能量、挥发性物质、内源激素、采后冷害和病害及基因甲基化等方面进行机制解析,重点从冷链物流体系和抗病防御系统的建立、保鲜剂的研发及配套技术、终端货架和外源激素破休眠技术等方面开展研究。

晚熟优质黄肉桃新品种美阳的选育

美阳是以中晚熟白肉桃优株99-1-44(丰白×金童5号)为亲本,通过自交育成的晚熟黄肉桃新品种,2020年通过河北省林木品种审定委员会审定。果实圆形,果顶凹,缝合线中,两半部对称,平均单果质量377 g,大果质量602 g。果皮底色黄,果面着红色,着色率20%~50%,茸毛少。果肉黄色,硬溶质,风味甜,可溶性固形物含量(w)13.3%~16.2%。离核,鲜食品质佳。去皮硬度为13.7 kg·cm-2,采收持续期10 d以上,室温下可贮藏10~15 d。树势强健,树姿半开张。叶片椭圆披针形;花蔷薇型,有花粉,自花结实率和自然坐果率高。石家庄地区3月下旬萌芽,4月上旬盛花,9月中下旬果实成熟,果实发育期173 d左右,11月上旬完全落叶。美阳桃适宜在河北省中南部及相似气候地区栽培。

河南郑州桃园桃病毒T的RT-PCR检测

通过选取河南省郑州市周边桃园生长不正常的树体叶片,进行RT-PCR检测桃病毒T的感染。结果表明,18份样品中检测到了6份样品存在病毒感染,检出率为33.3%。检出病毒的桃树样品分布在新郑市多个乡镇的果园,共有5个品种检出病毒;来自巩义市的样品未检测出桃病毒T。检出病毒的桃品种既有生产上的老品种,又有近几年栽植的新品种。结合多个桃园的病毒检出,说明病毒T已在生产中存在较长时间,并在局部区域呈扩散趋势。

晚熟桃新品种嵩源一号的选育

嵩源一号是青州蜜桃自然实生品种。果实卵圆形,果顶微凸,平均单果质量138 g,最大单果质量264 g;果皮底色淡绿色,80%以上着深红色,茸毛密度中等;果肉淡绿色,近核处花青苷含量较高,硬溶质,风味脆甜,可溶性固形物含量(w)14.1%,果实去皮硬度8.5 kg·cm^(-2),离核,耐贮运,室温放置10 d、冷藏放置1个月风味基本不变。花蔷薇型,有花粉,自花结实率高,早期丰产性好。果实发育期130 d,在潍坊8月中下旬果实成熟,比青州蜜桃早1个月左右。抗寒性、抗旱性强,适宜在山东、河北等北方桃产区推广栽植。