Breeding melon(Cucumis melo)with resistance to powdery mildew and downy mildew

Melon(Cucumis melo L.)production is often restricted by a plethora of pests and diseases,including powdery mildew and downy mildew caused respectively by the fungal species Podosphaera xanthii/Golovinomyces orontii and oomycete species Pseudoperonospora cubensis.Many efforts have been directed on identification of resistant sources by screening(wild)melon germplasm.In the current review,we summarized such efforts from various publications of the last 50 plus years.Resistance to powdery mildew has been identified in 239 melon accessions and downy mildew resistance in 452 accessions of both C.melo and the wild relative species C.figarei.Among the resistance sources,C.melo var.cantalupensis accessions PMR 45,PMR 5,PMR 6,and WMR 29 as well as C.melo var.momordica accessions PI 124111,PI 124112,and PI 414723 have been considered as the most valuable germplasm because multiple resistance genes have been identified from these accessions and are widely used in melon resistance breeding.Further genetic mapping in a number of resistant sources has enabled identification of 25 dominant genes,two recessive genes and seven QTLs conferring powdery mildew resistance,as well as eight dominant genes and 11 QTLs for downy mildew resistances.Based on the reported sequences of associated markers,we anchored physically(many of)these genes and QTLs to chromosomes of the melon cv.DHL92 genome.In addition to presenting a comprehensive overview on powdery mildew and downy mildew resistance in(wild)melon germplasm,we suggest strategies aiming at breeding melon with durable and broad-spectrum resistance to pathogens and pests.

Growth promotion of interspecific hybrid embryos between Cucumis anguria and Melon(C. melo) by fruit heating

Wild species of the genus Cucumis, such as C. anguria, are resistant to various melon(C. melo) diseases such as Fusarium wilt race 1.2 and are anticipated as genetic resources of melon. However, in the interspecific crosses between C. anguria and melon, the abortion of the embryos was observed in the early growth stage and could not be regenerated even when cultured. Therefore, for embryo rescue, it is necessary to promote embryo growth during abortion occurrence. This study investigated the effects of fruit heating on embryo growth in interspecific hybrids of C. anguria and melon. In the heating device, the minimum night temperature around the fruit was maintained above 21.5 °C. The ovule grain area of C. anguria × MR-1 with fruit heating was significantly enlarged compared to that without fruit-heating. It was also significantly enlarged compared with the ovule grain area of C. anguria self-pollination. Although, in C. anguria × MR-1 without fruit-heating, no embryo was observed until 10 days after pollination(DAP), and pre-embryos were observed at 13 DAP. Conversely, in C. anguria × MR-1 with fruit-heating, pre-embryos were even observed at 10 DAP. These results suggest that the possibility of embryo or ovule culture regeneration has increased due to embryo growth promotion.

来自甜瓜属(Cucumis melo L.)6个变种部分品种货架期差异比较

对甜瓜属6个变种的13个材料的货架期及相关因素进行了测定比较。结果表明,来自var.saccharinus和inodorus的5个品系表现出乙烯释放速率和鲜样质量损失率很低,货架期显著优于其它变种的材料。var.reticulatus虽然乙烯释放量较低,但由于果肉软化,其货架期短于var.inodorus。var.cantalupensis,makuwa和acidulus货架期短。相关性分析显示货架期还与果实发育期及果实质量存在高度相关,而果实表面的网纹结构与乙烯释放速率、鲜样质量损失速率及货架期并无显著的相关性。

河套蜜瓜(Cucumis melo L cv Hetau)子叶的组织培养和再生植株研究

切取在ＭＳ培养基中生长５ｄ的河套蜜瓜子叶，在ＭＳ＋ＮＡＡ１＋ＢＡ０．１的培养基中予培养３ｄ后转入芽诱导培养基（ＭＳ＋ＺＴ６）诱导生芽，待芽长２ｃｍ左右转入ＭＳ＋ＩＢＡ０．５诱导生根，１０ｄ后再转入沙质土壤的营养缶本中成苗，整个成苗过程约需６０～７０ｄ，再生植株诱导率可达５５％。

哈密瓜(Cucumis melo L.)致腐真菌的鉴定

研究从哈密瓜表面分离出引起其腐败的菌株A和菌株B,并采用显微镜形态学观察、表型特征和分子生物学三种方法对其进行鉴定。结果发现菌株A可利用碳源包括杏苷、糊精、D-半乳糖、D-葡萄糖酸、麦芽糖、肝糖、L-鼠李糖、L-山梨糖、L-乳酸等72种碳源,其ITS rDNA序列与尖孢镰刀菌甜瓜转化型(Fusarium oxysporum f.sp.melonis)的同源性为99%,分支长度为0.00。菌株B可利用碳源包括L-阿拉伯糖、D-果糖、丙三醇、蔗糖和木糖醇等54种碳源,其ITS rDNA序列与链格孢菌(Alternaria alternata)的同源性为100%,分支长度为0.00。因此,推断菌株A为尖孢镰刀菌甜瓜转化型,菌株B为链格孢菌。

Effects of Meteorological Conditions on Yield and Quality of Facility Hami Melon

With different varieties of facility Hami melon(Cucumis melo var. sacchairinus) as test materials, the effects of meteorological conditions on the yield and quality of different varieties of facility Hami melon were analyzed. The results showed that among the yield and quality traits of melon, the variation degree of average single melon weight was the highest, and the coefficient of variation was 33.05%. The variation degree of leaf area index was the lowest, and the coefficient of variation was 11.00%. Through the correlation analysis of meteorological factors with the yield and quality of facility Hami melon, it was found that the quality traits of facility Hami melon were significantly positively correlated with maximum temperature and sunshine duration, and significantly negatively correlated with precipitation. The yield traits were positively correlated with maximum temperature, sunshine duration and precipitation.

The Study of Allelochemicals of the Melon Fly (Myiopardalis pardalina Bigot.)

This study describes the isolation, identification of allelochemicals of the melon fly (Myiopardalis pardalina Bigot.), using the GC-MS method. A food attractant has been identified and a method for the synthesis of its synthetic analogue has been developed. Also, a route for the synthesis of para pheromone, raspberry ketone, has been proposed.

Modeling Study of Fruit Morphological Formation in Melon

Modeling of fruit morphological formation in melon is important for realizing virtual and digital plant growth.The objective of this study was to characterize the changes in patterns of fruit growth characters during plant development.In cultivar experiments,a high-resolution wireless vision sensor network has been developed to realize non-contact automatic uninterrupted measurement of the fruit shape micro-change （fruit size,color,and net）.Results showed that the fruit swelling process （vertical and horizontal diameters） exhibited a slow-rapid-slow pattern,which could be well described with a logistic curve against growing degree days （GDD）;fruit color changes based on the RGB values could be represented by quadratic relationship to cumulative GDD;the fruit net changes over growth progress could be partitioned into three phases according to the time interval.The first phase was from 1 to 30 days after pollination （DAP）,in which the vertical stripe appeared at fruit middle part and the horizontal stripe at fruit petiole and hilum part as well;the second phase was from 30 to 40 DAP,the horizontal stripe occurred at fruit middle part and the net was formed;the third phase was the process started from 40 DAP,the netted breadth and thickness were gradually increased.The model was validated with the independent data from the experiment,and the mean RMSE （root mean square error） of fruit were 0.36 and 0.28 cm for vertical and horizontal diameters,11.9 for fruit color,and 0.45 cm for stripe length and diameter at varied GDD,respectively.This work is beneficial to a reliable foundation for study the relationship between morphological formation and physiological change of the melon fruit internally and then realize the intelligent precision management to improve the yield and quality of greenhouse melon production.

Inhibitive Mechanisms of Two Silicon Compounds on Powdery Mildew of Melon

Seedlings of Yujinxiang melon were used to investigate the effect and inhibitive mechanism of sodium silicate and nanosized silicon oxide on powdery mildew. The results showed that the severity of powdery mildew on melon seedlings was lowered significantly by treatment with either of the two silicon compounds, although the effect of sodium silicate was more powerful than silicon oxide. Application of sodium silicate to the seedlings caused significant increases in the activity of peroxidase (POD) and of β-1,3-glucosidase (GLU), both enzymes are known to be associated with the disease defence systems of plants. SEM-EDX analysis of sodium silicate-treated leaves of the melon seedlings showed an elevated level of silicon deposit at stomata and epidermis. Treatment with nanosized silicon oxide also resulted in a similar increase in silicon deposit, but the treatment did not cause a significant increase in POD activity.

QTL-seq identifies major quantitative trait loci of stigma color in melon

Stigma color plays an important role in pollination.In nature,melon(Cucumis melo L.)stigmas are either yellow or green;however,a review of the literature found no report on how stigma color affects pollination and fruit development in melon.Here,we used an F_(2)melon population derived from a cross between‘MR-1’(P_(1),with green stigmas)and‘M1–32’(P_(2),with yellow stigmas),and performed genetic analysis and mapping.The results of bulked segregant analysis allowed the identification of genetic loci controlling stigma color on chromosomes 6 and 8.An F2 population consisting of 150 individuals was used for initial mapping.A genetic map of 304.17 cM was constructed using 37 cleaved amplified polymorphism sequence(CAPS)markers.We identified one major quantitative trait locus(QTL)and one minor QTL for stigma color.The major QTL GS8.1 was further mapped to a 4.13 cM interval between CAPS markers 8C-10 and 8C-16,which explained 27.04%of the phenotypic variation.In addition,GS6.1 was mapped between E-49 and 6A-7,explaining 18.6%of the phenotypic variation.This study provides a theoretical basis for the fine mapping and cloning of melon genes controlling stigma color.

Melon Seedlings Phytomass under Poultry Litter Biochar Doses

The use of organic waste for the preparation of seedling substrates is an important environmental and economic option. In this perspective, substrates using biochar emerges as an alternative for seedling production due to their favorable physical and chemical characteristics. The present study aimed to evaluate the efficiency of doses of poultry litter biochar as a substrate constituent for the production and quality of the seedlings. The work was conducted in a semi protected environment, belonging to the Federal University of Campina Grande—UFCG. The statistical design used was completely randomized in a 6 × 2 factorial scheme, consisting of 6 doses of biochar (0, 4, 8, 12, 16 and 20 t∙ha−1) and two varieties of melon (Yellow and Hales Best Jumbo) with 4 repetitions totaling 48 experimental units. The fresh and dry plant phytomass mass (aerial, roots and total), root length and the quality of seedlings were evaluated. It was concluded that the addition of poultry litter biochar to the substrate was beneficial, promoting an increase in the analyzed seedling variables, being the ideal dose for good development of melon seedlings 12 t∙ha−1. The Yellow variety presented a better response than the Hales Best Jumbo to the charcoal application. Considering the advantages of the use of poultry litter biochar on the substrate composition, found in the present study, its utilization constitutes a viable alternative for the development of melon seedlings and for the environmental disposal of the poultry litter.

Wild melon: a novel non-edible feedstock for bioenergy

In the present research work, a non-edible oil source Cucumis melo var. agrestis （wild melon） was systematically identified and studied for biodiesel production and its characterization. The extracted oil was 29.1% of total dry seed weight. The free fatty acid value of the oil was found to be 0.64%, and the single-step alkaline transesterification method was used for conversion of fatty acids into their respective methyl esters. The maximum conversion efficiency of fatty acids was obtained at 0.4 wt% NaOH （used as catalyst）, 30% （methanol to oil, v/v） methanol amount, 60 ℃ reaction temperature, 600-rpm agitation rate and 60-min reaction time. Under these optimal conditions, the conversion efficiency of fatty acid was 92%. However, in the case of KOH as catalyst, the highest conversion （85%） of fatty acids was obtained at 40% methanol to oil ratio, 1.28 wt% KOH, 60 ℃ reaction temperature, 600-rpm agitation rate and 45 min of reaction time. Qualitatively, biodiesel was characterized through Fourier transform infrared spectroscopy （FFIR） and gas chromatography and mass spectroscopy （GC-MS）. FTIR results demonstrated a strong peak at 1742 cm-1, showing carbonyl groups （C=O） of methyl esters. However, GC-MS results showed the presence of twelve methyl esters comprised of lauric acid, myristic acid, palmitic acid, non-decanoic acid, hexadecanoic acid, octadecadienoic acid and octadecynoic acid. The fuel properties were found to fall within the range recommended by the international biodiesel standard, i.e., American Society of Testing Materials （ASTM）： flash point of 91℃, density of 0.873 kg/L, viscosity of 5.35 cSt, pour point of - 13 ℃, cloud point of -10 ℃, total acid number of 0.242 mg KOH/g and sulfur content of 0.0043 wt%. The present work concluded the potential of wild melon seed oil as excellent non-edible source of bioenergy.

甜瓜蔓枯病抗性QTL定位的研究

【目的】探讨甜瓜（Cucumis melo L.）蔓枯病抗性遗传规律并筛选出抗性连锁分子标记位点。【方法】高抗蔓枯病品系JGD-3做母本，感蔓枯病品系S717做父本，杂交构建包含122个单株的R代群体，各单株分别自交得到相应的F，代家系；分别于2010年秋季和2011年春季叶片人工喷雾苗期接菌，完成蔓枯病抗性遗传规律鉴定；基于已构建对应分子标记连锁图谱，联合复合区间定位蔓枯病抗性数量基因位点（QTL）。【结果】两种环境下共检测到甜瓜蔓枯病抗性5个QTL（gsb1．1，gsb2．1，gsb3．1，gsb5．1和gsb6．1）作用位点，位于连锁群1，2，3，5和6上，单个QTL解释贡献率于2．5％。23．0％之间。两种环境中稳定重复检测的QTL是gsb1.1和gsb6．1；gsb2．1在2010年秋季被检测出．gsb3．1和gsb5．1在2011年春季检测到。两种环境下检测的QTL解释表型变异总和是42．0％（2010年秋季）和49．0％（2011年春季）。【结论】以甜瓜JGD-3为抗源鉴定蔓枯病抗性为数量遗传性状由多基因共同控制，有2个QTL位点在两种环境中被重复检测；与QTLs紧密连锁的标记（〈5cM）为分子标记辅助选择（MAS）甜瓜抗蔓枯病品系和蔓枯病抗性基因分离、克隆提供了技术支撑。

甜瓜子叶不定芽分化过程中PAL活性和木质素含量变化研究

用组织培养的方法使甜瓜子叶脱分化形成愈伤组织，继而在分化培养基上形成不定芽。以此为系统，测定不定芽发生过程中ＰＡＬ活性变化和木质素含量变化．以肉桂酸、香草酸、苯甲酸、阿魏酸和咖啡酸为抑制剂，研究它们对不定芽发生的影响以及对系统中ＰＡＬ活性变化和木质素含量变化的影响。结果表明，五种抑制剂均抑制不定芽的发生。ＰＡＬ活性、木质素含量和愈伤组织分化成管胞、不定芽发生四者之间有密切的关系。

甜瓜种子萌发和幼苗生长对NaCl胁迫的响应

在盆栽条件下研究了NaCl胁迫对黄河蜜和白沙蜜甜瓜种子萌发和幼苗生长的影响。结果表明：NaCl胁迫对甜瓜种子吸水和累计发芽率影响较小，但明显延缓后期吸水和发芽进程。50mmol·L^-1以上NaCl浓度下，甜瓜种子相对发芽指数、相对活力指数和胚根生长量均下降。NaCl胁迫抑制甜瓜幼苗高度、株叶面积增长和干物质积累，抑制作用具有浓度和时间依赖性。NaCl胁迫对甜瓜幼苗形态生长的抑制作用强于对物质积累的抑制作用，对根系干物质积累的抑制作用高于对地上部干物质积累的抑制作用，对白沙蜜的抑制作用强于对黄河蜜的抑制作用。甜瓜种子和幼苗能适应的临界NaCl浓度在100～150mmol·L^-1之间，厚皮甜瓜可能更适合作为咸水灌溉和盐碱地生产的经济作物。

NaCl胁迫对甜瓜幼苗叶片膜脂过氧化和渗透调节物质的影响

研究了厚皮甜瓜黄河蜜和薄皮甜瓜白沙蜜在NaCl胁迫下甜瓜幼苗叶片相对膜透性、丙二醛(MDA)和保护酶SOD、CAT、POD活性及脯氨酸、可溶性糖含量的变化。结果表明,随盐浓度的增加和时间的延长,甜瓜叶片细胞膜相对透性、MDA含量、脯氨酸含量和可溶性糖含量逐渐增大。叶片SOD、POD和CAT酶活性对NaCl胁迫的响应具有浓度和时间依赖性。NaCl对黄河蜜叶片膜系统的伤害小于对白沙蜜的伤害。渗透调节是甜瓜在盐胁迫下的适应性表现。

酥瓜(Cucumis melo var. conomon Group)基因组DNA提取及RAPD分子标记反应体系的建立

本研究以改良的CTAB法提取酥瓜基因组DNA,利用正交设计L_(16)(4~5),对酥瓜RAPD-PCR反应体系的5个影响因素(引物,dNTPs,Taq DNA聚合酶,Mg^(2+)和模板DNA)在4个水平上进行优化试验,并在30~50℃范围内摸索退火温度,建立适合酥瓜RAPD-PCR反应体系。研究表明,在25μL反应体系中,含有引物0.8μmol/L、dNTPs 0.3μmol/L、Taq DNA聚合酶1 U、Mg^(2+)0.5 mmol/L、DNA模板30 ng为最佳反应体系,RAPD-PCR扩增程序中最佳退火温度为37.6℃。该体系有助于酥瓜种质资源的遗传多样性分析评价。

甜瓜种子醇溶蛋白的反相HPLC分析鉴定(英文)

针对目前国内甜瓜的主栽品种K96 8× 6 1、T 5×red1 2 8和 94× 8 1的自交系及杂交种种子醇溶贮藏蛋白进行反相HPLC法分离。结果表明 ,其色谱图明显不同 ,可以用于该品种 (系 )的鉴定 ,认为RP HPLC技术是一种快速、准确、可信的甜瓜品种鉴定手段。

Antihyperglycemic and antihyperlipidemic activities of wild musk melon (Cucumis melo var. agrestis) in streptozotocin-nicotinamide induced diabetic rats

Objective:Wild musk melon(Cucumis melo var.agrestis,CMA)is one of the edible plants form Tamil Nadu.Traditionally,this plant was used as diabetic diet(leaves of CMA with Momordica charantia leaves),but there is no scientific report on antidiabetic action of this plant material.Hence,the current research work was designed to evaluate the antihyperglycemic and antihyperlipidemic effect of hydroalcoholic extract of CMA leaves(HALEC)in streptozotocin(STZ)-nicotinamide(NIC)-induced diabetic rats.Methods:Diabetes was induced by administration of STZ(60 mg/kg,i.p.)after 15 min of NIC(120 mg/kg i.p.)administration.The diabetic rats were treated with HALEC(300 and 600 mg/kg,p.o.,respectively)for 21 d.Results:After the management with HALEC,blood glucose,HbA1c levels,total cholesterol,LDL cholesterol,triglycerides levels,glycogen phosphorylase and glucose-6-phosphatase levels were significantly diminished in diabetic rats.However,haemoglobin level,HDL cholesterol,liver glycogen,total protein,hexokinase,glucose-6-phosphate dehydrogenase levels were significantly increased in HALEC treated diabetic rats.The histopathological studies of the pancreas in HALEC-treated diabetic rats showed almost normal appearance.L6 cell line study revealed the increased glucose uptake activity of HALEC.High performance thin layer chromatography(HPTLC)analysis confirms the presence of active principles such as rutin,gallic acid and quercetin in HALEC.Conclusion:The results indicated that HALEC possess significant antihyperglycemic and antihyperlipidemic activity in STZ-NIC-induced typeⅡdiabetic rats with protective effect.This research work will be useful for the isolation of active principles and development of herbal formulation in phytopharmaceuticals.

甜瓜果实相关性状QTL分析

以WI998(厚皮网纹、纯雌株甜瓜品系)为母本,以3-2-2(薄皮、雌雄异花同株甜瓜品系)为父本进行杂交,通过单粒传得到了含有124个F6:7家系的重组自交系群体,构建遗传连锁图谱。在608对SSR引物中筛选出亲本间有多态性的引物150对,多态率为24.67%;该图谱包含17个连锁群,覆盖基因组长度为1246.67cM,标记间的平均距离为9.59cM。应用复合区间作图法对甜瓜单果质量(Fw)、果实硬度(Ff)、果实长度(Fl)、果形指数(Fsi)及果肉厚度(Ft)等性状进行QTL分析,共检测到15个QTL,分别分布在第1、4、5、6、8、10、13、14、15、17连锁群上,其中8个QTL贡献率超过10%,位于第13连锁群的QTLFf13.2贡献率最大,为26.45%。标记ECM87与Fsi8.2位于同一位点,标记CM33与Fsi15.1紧密连锁,遗传距离为0.6cM。