Development and application of KASP marker for high throughput detection of the seedless trait in grapevine

Molecular marker-assisted selection(MAS) can significantly accelerate and improve the efficiency of the breeding process in seedless grape cultivars. In this study, we developed the KASP_VviAGL11 and VviAGL11_410 markers based on a single nucleotide polymorphism(SNP) site(Chr18: 26889437(A/C)) of the VviAGL11 gene, and compared them with previously reported SSR markers p3_VvAGL11 and 5U_VviAGL11 by testing 101 cultivars and 81 F1 hybrid progenies. The results showed that both of the proposed markers obtained 100% accuracy rates in detecting allele A, which was closely associated with the seedless trait in grapes, while p3_VvAGL11 and 5U_VviAGL11 had lower accuracy rates due to their tendency to produce false positives. After careful evaluation of the technical advantages and disadvantages associated with these markers, we concluded that KASP_VviAGL11 was superior in terms of simplicity,cost-effectiveness, efficiency, and accuracy. Thus, we optimized the process of molecular MAS for seedless grapes,focusing on the KASP_VviAGL11 marker as a central component, to provide key technical support for the development of new seedless grape cultivars.

Screening Test of Small Seedless Watermelon Varieties in Beijing Area

[Objectives]This study was conducted to select small seedless watermelon varieties with excellent quality and high yield suitable for planting in Beijing.[Methods]Under the conditions of facility cultivation in Beijing,a screening test was conducted on seven small seedless watermelon varieties for growth process,field traits,yield traits,fruit quality,and disease resistance.[Results]Varieties Mitong,Motong and Tianbao Xiaowuzi had a short growth period and relatively stable growth,and bore fruit easily,and their female flowers were closely spaced.Their yields exceeded 60000 kg/hm~2,ranking in the top three among all varieties.The fruit had a thin skin,a bright red flesh color,and a high mass fraction of soluble solids in the center.The flesh was tight or crispy,and tasted good.They also showed good disease resistance.Overall,they showed excellent comprehensive agronomic traits,and are thus suitable for facility cultivation in Beijing and its surrounding areas.[Conclusions]This study provides a theoretical basis for the upgrading of varieties and the increase in production and farmers'income in the suburbs of Beijing.

Effects of Different Concentrations of Paclobutrazol on Seedling Quality of Small Seedless Watermelon in Autumn

[Objectives]The paper was to explore the effects of different concentrations of paclobutrazol on seedling quality of small seedless watermelon in autumn.[Methods]The leaves of watermelon seedlings were sprayed with 30,50,80 and 120 mg/L paclobutrazol at cotyledon expansion stage,and those sprayed with tap water were used as control.[Results]All the treatments of paclobutrazol effectively inhibited the excessive growth of watermelon at seedling stage,significantly enhanced the leaf quality of watermelon seedlings and promoted root growth.The seedlings treated by 50 mg/L paclobutrazol had the best performance compared with the control:a decrease of hypocotyl by 37.9%,an increase of plant dry weight by 46.55%,significantly increased seedling strength index,deep green leaf color,thick leaves,an increase of specific leaf weight by 28.13%,and significantly heavier root weight and longer length.[Conclusions]The results will provide a reference for strong seedling cultivation of small seedless watermelon.

Flame Seedless葡萄胚珠、胚乳及胚发育与败育的研究

对Flame Seedless葡萄胚珠、胚乳及胚的发育和败育过程进行了系统的细胞学观察,并以有核葡萄品种北醇为对照对Flame Seedless的胚珠重量及纵横径进行了测定.结果表明:(1)Flame Seedless内、外珠被及珠孔发育异常,20%～30%的子房未出现受精现象,受精的胚珠重量和纵横径随着胚珠的发育,先呈增加趋势,在某一时期达到最高值,随后下降,最终退化为痕迹.(2)大约有30%的胚乳核能够进行正常分裂,形成胚乳组织,胚乳在花后30 d开始退化,其余胚乳核分裂异常.合子在盛花后第19天进行第一次分裂,经过二细胞原胚→多细胞原胚→球形胚,此后胚开始退化;也有的合子始终不发生分裂,最终退化.(3)由于胚乳分裂异常和提早退化,胚缺乏营养致使其发育中止和败育.(4)Flame Seedless胚挽救的最佳接种时期在花后第37天.

Influence of Gamma Irradiation on Seedless Citrus Production: Pollen Germination and Fruit Quality

Seedlessness is a desirable characteristic in citrus fruits sold for fresh consumption. Gamma irradiation is widely used to obtain seedless citrus fruits. Here, different clones of the self-incompatible parthenocarpic ‘Moncada’ mandarin, obtained by gamma irradiation, were studied to assess seedlessness, pollen germination, fruit characteristics and qua- lity attributes. Findings indicate that irradiation altered aspects other than seedlessness, such as pollen germination, and some of the clones presented different weight, size, acidity and maturity index. Fruit quality and nutritional bio- components were affected differently;some clones presented no changes compared to the control ‘Moncada’ man-darin, while other clones showed significant differences. In general, all clones examined presented low seed numbers and re- duced pollen viability. Some of these clones, which ripen late in the season and whose fruit quality is maintained or improved, are in the process of registration.

Rapid Seedless Synthesis of Gold Nanoplates with Microscaled Edge Length in a High Yield and Their Application in SERS

We report a facile and reproducible approach toward rapid seedless synthesis of single crystalline gold nanoplates with edge length on the order of microns.The reaction is carried out by reducing gold ions with ascorbic acid in the presence of cetyltrimethylammonium bromide(CTAB).Reaction temperature and molar ratio of CTAB/Au are critical for the formation of gold nanoplates in a high yield,which are,respectively,optimized to be 85 °C and 6.The highest yield that can be achieved is 60 % at the optimized condition.The synthesis to achieve the microscaled gold nanoplates can be finished in less than 1 h under proper reaction conditions.Therefore,the reported synthesis approach is a time-and costeffective one.The gold nanoplates were further employed as the surface-enhanced Raman scattering substrates and investigated individually.Interestingly,only those adsorbed with gold nanoparticles exhibit pronounced Raman signals of probe molecules,where a maximum enhancement factor of 1.7 9 10~7 was obtained.The obtained Raman enhancement can be ascribed to the plasmon coupling between the gold nanoplate and the nanoparticle adsorbed onto it.

QTL-seq analysis of the seed size trait in grape provides new molecular insights on seedlessness

Seedlessness in grape(Vitis vinifera)is an important commercial trait for both the fresh and drying markets.However,despite numerous studies,the mechanisms and key genes regulating grape seedlessness are mostly unknown.In this study,we sequenced the genomes of the V.vinifera seeded cultivar‘Red Globe’,the seedless cultivar‘Centennial Seedless’,and the derived hybrids.Nonsynonymous single nucleotide polymorphisms(SNPs)were identified by genome sequencing and analyzed using published transcriptome data.Nonsynonymous SNPs occurred in genes related to seed development,which were identified as protein kinases,transcription factors,and cytochrome P450 s and showed differential expression during ovule development in both seeded and seedless grapes.These nonsynonymous SNP-associated genes were mainly involved in biological processes such as hormone balance,seed coat and endosperm development,reproductive organ development,oxidation and reduction,senescence and cell death.A potential quantitative trait locus(QTL)region associated with seed size was characterized based on the SNP-index,and expression analysis of candidate genes in the QTL region during ovule development in multiple seeded and seedless grape cultivars were conducted.Three SNPs were further subjected to SNa Pshot analysis and one SNP in G8 showed 67.5%efficiency in the grape progeny validation.Overall,the data obtained in this study shed light on the differences in seed development between seeded and seedless progeny at the genomic level,which provides valuable resources for future functional studies and grape breeding.

Immature Embryo Rescue and in Vitro Development Evaluation of Intraspecific Hybrids from Brazilian Seedless Grapevine“Superior×Thompson”Clones

The fruit production for export is an economically significant activity in the Valley of S?o Francisco River, especially in the irrigated lands of Petrolina-PE/Juazeiro-BA, Brazil. The development of new genetic material most suitable to the tropical climate and the demands of the consumer market have led to the selection of new seedless grapes cultivars. In this case, the use of the embryo rescue technique has produced satisfactory results for obtaining such materials, especially in the semiarid region. This study aimed to evaluate the in vitro development of intraspecific hybrids of grapevine (Vitis vinifera L.), derived from the rescue of immature embryos resultant from the crossing of “Superior Seedless” and “Thompson Seedless” Brazilian clones. To establish and develop the cultivation, the culture media was supplemented with 30 g/L sucrose, 0.1 g/L myo-inositol, 0.002 g/L glycine, 0.1 mg/L indoleacetic acid (IAA), 6.5 g/L of agar, adjusted pH to 5.7. The experiment was evaluated after 90 days. The variables measured were: number of nodes, number of leaves, plant height (cm), number of roots and length (cm) of the root system and internodes. The period of 60 days of in vitro culture of ovules resulted in the highest values of embryos (about 50%), as well as better characterized developmental stages with higher germination (47.3%). The three types of hybrid grapes evaluated in micropropagation showed very similar values of the measured parameters, even having originated from embryos of different developmental stages.

Cloning and Sequence Analysis of a Cysteine Proteinase Inhibitor Gene from Seedless Litchi

[Objective] This study aimed to clone and analyze the cysteine proteinase inhibitor gene from seedless litchi. [Method] According to the EST sequence of cysteine proteinase inhibitor in constructed SSH subtractive library of seedless litchi abortion, nucleotide sequence of the cysteine proteinase inhibitor gene was obtained by using RACE technology and analyzed by using bioinformatics software. [Result] A cysteine protease inhibitor gene was obtained with the sequence of 635 bp containing a 321 bp open reading frame. It was predicted that the encoded protein contained 106 amino acids with conserved domain of cysteine proteinase inhibitor and had relatively high homology with the cysteine proteinase inhibitor gene of several species. [Conclusion] This study laid the foundation for further exploring the physiological functions of this cysteine proteinase inhibitor gene in plants.

A Good Seedless Ponkan Cultivar—Qianyang Seedless Ponkan

Qianyang Seedless Ponkan selected from common ponkan is a sport deviation cultivar without any seeds in its fruit. Matures in mid November, it has bigger avg.124.5g fruit, and the yield is 30 t ha-1 after 5 years' growing. There are no obvious in-year or off-year phenomena. Its fruits can store well without any treatments at room temperature for three or four months.

大果少核椪柑新品种华柑3号的选育

华柑3号是通过鄂柑1号椪柑珠心胚实生苗倍性变异而培育的四倍体大果少核椪柑新品种。果实扁圆形,果实大,平均横径74.08 mm,纵径62.63 mm,平均单果质量179.94 g,平均果皮厚度3.45 mm。果肉橙黄色,肉质脆嫩,酸甜爽口,风味浓,可溶性固形物含量(w,后同)为14.49%,可滴定酸含量为1.16%,可食率为71.6%,化渣性好;种子少,平均2.7粒·果^(-1);树势中等偏强,树姿较直立,结果母枝以春梢和秋梢为主;在湖北武汉地区,12月中下旬果实成熟,可挂树至翌年1月;丰产性中等,按3.0 m×4.0 m密度定植的5年生树,每666.7 m^(2)产量可达1500 kg;适宜在年均温度16℃左右,冬季无霜冻、绝对最低温度在-5℃以上的区域种植。

浙江地方特色品种温岭高橙无核潜力新种质创制及分子鉴定

【目的】温岭高橙是浙江台州地方特色品种,栽培历史悠久,且具有一定的保健和药用价值,但果实有核限制了其在台州以外地区的发展,因此利用细胞工程高效育种技术对温岭高橙进行无核化改良。【方法】通过2条育种途径,一是以二倍体温岭高橙为母本与异源四倍体为父本倍性杂交,授粉后90 d利用幼胚离体挽救培养和流式细胞仪倍性鉴定创制三倍体无核新种质;二是以雄性不育胞质杂种华柚2号为母本与温岭高橙有性杂交,通过成熟种子催芽播种,创制二倍体无核新种质。利用SSR分子标记对杂交后代进行分子鉴定。【结果】以温岭高橙为母本、异源四倍体NS和BDZNS为父本配置2个倍性杂交组合,授粉145朵花,坐果74个;胚抢救幼嫩种子1520粒,离体培养获得再生植株553株;用流式细胞仪对再生植株进行倍性鉴定,获得三倍体45株、四倍体8株;以华柚2号为母本与温岭高橙有性杂交,授粉69朵花,坐果20个,获得成熟种子312粒;通过催芽播种获得实生后代203株,倍性鉴定均为二倍体;用SSR分子标记对2个倍性杂交组合的21株三倍体和8株四倍体后代及华柚2号×温岭高橙随机选取的29株二倍体后代进行分子鉴定,显示所鉴定的三倍体及二倍体后代均含有父本特异条带,为其杂交双亲的有性后代,而倍性杂交获得的四倍体后代与母本条带完全一致,推测其为母本珠心细胞自然加倍形成的同源四倍体(双二倍体)。【结论】研究结果为温岭高橙无核新品种培育奠定了宝贵的材料基础。

鲜食葡萄无核化研究进展

优质、大粒、无核鲜食葡萄深受消费者青睐,利用植物生长调节剂进行葡萄无核化生产已成为获取优质、大粒、无核鲜食葡萄的重要途径,并在生产上得到广泛应用。本文综述了葡萄无核化机理、常用植物生长调节剂种类及其使用浓度和处理方法、无核化栽培技术及需注意的问题等,以期为葡萄无核化生产提供理论依据和参考。

无籽西瓜新品种墨绿无籽5号的选育

墨绿无籽5号是以自交系GR4x-2为母本,以2x-55为父本配制而成的大果型无籽西瓜一代杂种。中晚熟,早春大棚栽培全生育期112 d(天)左右,果实发育期40 d(天)左右。果实正圆形,果皮墨绿色覆深绿色网条纹,果皮厚度1.2 cm,硬度27 kg·cm^(-2)左右,耐裂、耐贮运;瓜瓤红色,中心可溶性固形物含量约12.1%,边部可溶性固形物含量约9.8%。

无核荔枝僵果病的病原菌鉴定、入侵途径及快速检测技术

2022年在海南无核荔枝上发现一种僵果病,与海南常见的荔枝病害炭疽病、酸腐病等病症差别明显,主要为害幼果,发病时幼果果实外观无明显变化,但无核荔枝完成疏果后,果实长至蚕豆大小时,发病果实的外果皮颜色变暗,剖开后内果皮发生不规则褐变,果实不再膨大,形成僵果,易造成严重的经济损失。本研究对该病害的病原菌进行分离和鉴定,对入侵途径和快速检测技术进行研究。结果表明:通过形态学鉴定、ITS、RBP2和TEF1基因序列分析,鉴定引起无核荔枝新型僵果病的病原菌为伯氏镰刀菌(Fusarium pernambucanum)。无核荔枝幼果期果实果皮受农事操作、风、刺吸性昆虫为害等损伤后,易受到病原菌的入侵发病,而果实表面无伤口时不发病。病原菌入侵主要集中在果实纵经3.2~4.8 mm的幼果期,随着果实的生长、果皮保护组织的增加和伤口的减少,病原菌难以入侵,果实发病率快速降低。基于TUB基因序列,以伯氏镰刀菌及其他分离获得的镰刀菌属菌株基因组DNA为模板进行扩增测序,根据序列信息设计筛选出一对伯氏镰刀菌的特异性引物,构建了基于普通PCR的快速高效分子检测方法,该检测方法灵敏、高效,可用于指导无核荔枝僵果病的早期诊断与预防。

冠菌素对‘火焰无核’葡萄果实着色及品质的影响

【目的】研究新型植物生长调节剂冠菌素Coronatine(COR)对‘火焰无核’葡萄果实着色及品质的影响,以期筛选出COR的最佳处理浓度,探明COR对葡萄果实着色及品质的影响,为COR的推广应用和葡萄生产提供理论依据和技术参考。【方法】以优良早熟葡萄品种‘火焰无核’葡萄为试材,果实转色初期设置3个COR蘸穗浓度处理,处理后至成熟期分6次采样,对果粒质量、果粒纵横径、果柄耐拉力、硬度、可溶性固形物、总酸、果实色泽、果皮花色苷、叶绿素、胡萝卜素、类胡萝卜素和酚类物质等指标进行连续测定,通过综合分析确定COR的最佳处理浓度。【结果】COR不同浓度处理均可以显著提高果实的单粒质量、可溶性固形物含量,降低总酸含量,提高果实固酸比,提高果皮花色苷含量,降低叶绿素含量,改善果实品质,促进果实着色。其中以COR 2000倍处理的综合品质最佳,与对照相比,可溶性固形物含量提高了8.43%,总酸含量降低了26.19%,固酸比提高了46.31%,花色苷含量提高了1.53倍,叶绿素含量降低了18.18%,a^(*)值提高了1.01倍,CIRG值提高了38.04%,h°值下降了67.13%;COR 3000倍处理促进着色的效果最佳,与对照相比,花色苷含量提高了1.61倍,叶绿素含量降低了27.27%,胡萝卜素降低了20%,a^(*)值提高了1.24倍,CIRG值提高了52.17%,h°值下降了82.78%。【结论】COR不同浓度处理均可提高‘火焰无核’葡萄果实品质,促进果实着色,其中在提高果实品质方面,COR2000倍处理效果最好;在促进果实着色方面,COR 3000倍处理效果最好。

4种植物生长调节剂对无核白葡萄果刷生长发育及采后落粒性的影响

无核白葡萄是我国重要的鲜食和制干兼用品种,但生产中普遍存在采后落粒问题。设置采前4种植物生长调节剂处理(100 mg/L S-ABA、10μmol/L MeJA、100 mg/L NAA+100 mg/L 6-BA、25 mg/L 2,4-D)研究无核白落粒率与果梗拉力的变化,以及果刷和其他相关指标间的联系。结果表明:2,4-D处理落粒率降低、果梗拉力增大,对应的果刷纵切与横切情况下的木质素染色面积显著大于其他处理,与落粒率呈显著负相关关系,与果梗拉力呈显著正相关关系,而纤维素并没有这种相关性;2,4-D处理上部果皮厚度显著大于其他处理,与落粒率呈负相关关系,与果梗拉力、果刷长度、果刷纵切及横切木质素染色面积呈显著正相关,但中部果皮厚度与其他指标不存在相似的关系;主成分分析结果显示,综合9个指标评价4种处理提高果梗耐拉力的效果由强到弱为25 mg/L 2,4-D>10μmol/L MeJA>100 mg/L NAA+100 mg/L 6-BA>100mg/L S-ABA。综上所述,无核白果实的果刷长度和其木质素含量是影响落粒率的重要因素,2,4-D可以诱导果刷内木质素积累,为果实落粒防控提供科学依据。

‘无核白’葡萄热风干燥特性及色泽研究

为探究干燥温度、装载密度和风速对‘无核白’葡萄干燥特性及色泽的影响,通过调查制干过程中葡萄重量变化,葡萄干含水量、色差,以及总酚、叶绿素、总糖、总酸含量等品质指标,计算出干率、绿品率、成干时间,分析不同处理对加工效率和葡萄干品质的影响。结果表明,干燥时间与物料温度和风速呈正相关,与装载量呈负相关,葡萄干总糖含量与果实的干燥工艺无相关性。当干燥温度为40℃时,‘无核白’葡萄会发生明显的褐变;而装载量超过15.62 kg·m^(-3)和风速超过2 m·s^(-1)时,褐变现象逐渐加重。综上,温度为35℃、风速1.0 m·s^(-1)、装载量7.81 kg·m^(-3)时,‘无核白’葡萄干燥时间为148 h,叶绿素、总酚含量分别为0.55、0.15 mg·g^(-1),与原材料色差为6.99,绿品率达到64%。葡萄干整体表现颗粒饱满,色泽良好。