苹果茎尖组培苗继代保存多年后繁殖特性研究

为解决种质离体保存的适宜年限等实用性问题,需了解多年继代保存的组培苗繁殖能力有无变化。本试验对继代保存不同年限的 ‘金冠’、‘乔纳金’和‘嘎拉’、‘富士’茎尖组培苗进行继代增殖能力、不定根诱导和离体叶片不定芽再生能力的研究。结果表明：外植体接种初期4年以内,即继代次数为24或40代时,‘富士’、‘金冠’、‘乔纳金’的新梢增殖能力较低,‘嘠拉’生根率较低,‘金冠’、‘富士’、‘嘠拉’离体叶片再生率较低,随着培养时间延长,继代次数增加,以上品种的继代增殖效率、生根能力及离体叶片再生能力均稳定在较高水平。长期继代保存的苹果品种茎尖组培苗（‘富士’已保存25年,‘金冠’、‘乔纳金’19年,‘嘠拉’10年）仍保持其器官再生能力。     

‘木瓜杏’叶片中矿质元素含量的动态变化研究

为了给‘木瓜杏’科学施肥、营养诊断等提供理论依据,以‘木瓜杏’品种为试材,采用电感耦合方法测定了‘木瓜杏’叶片生长发育期间Ca、P、K、Mg、Fe、Zn、Cu、Mn、Al元素的含量变化。结果表明,‘木瓜杏’叶片中Ca与Mg元素,Cu、Zn与P元素,Fe与Al元素的含量呈现出相似的变化规律,K、Mn元素含量的变化趋势各异。‘木瓜杏’叶片中的各种矿质元素之间存在着协同和拮抗的动态平衡作用过程。7月中旬是适合叶分析营养诊断的适宜时期。     

根域限制对‘宝满’葡萄光合特性及糖代谢的影响

为了探究根域限制栽培对葡萄生理特性的影响,以3年生‘宝满’葡萄植株为试验材料,采用根域限制处理方法,对光合特性及糖代谢相关指标进行测定。结果表明：根域限制处理的‘宝满’葡萄植株与对照Pn日变化趋势一致,而处理植株Pn、Gs、Tr显著低于对照,处理植株叶片叶绿素含量低于对照;在果实发育中后期,根域限制下‘宝满’葡萄果实的可溶性总糖含量、糖代谢相关酶活性明显高于对照。这些结果表明,根域限制可能主要影响果实发育后期糖代谢相关酶活性进而影响‘宝满’葡萄的糖代谢和积累,并显著提高果实品质。     

豫西不同基因型烤烟香气成分和评吸质量的分析

通过对豫西不同基因型烤烟香气成分和评吸质量的评价,分析其中存在优劣差异,为指导烟区品种资源合理搭配提供参考依据。采用气相色谱/质谱联用仪（GC/MS）内标定量检测挥发性香气物质,用单料烟感官评吸评价法,综合分析豫西不同基因型烤烟的内在质量。结果表明：不同基因型的总香气成分含量由高到低依次为‘洛阳4号’、‘中烟100’、‘K326’、‘云烟202’和‘长脖黄’。不同基因型新植二烯含量与香气物质总量的变化趋势相一致;苯丙氨酸类含量最高的基因类型是‘K326’,其次是‘中烟100’和‘洛阳4号’;棕色化产物类含量最高的基因类型是‘中烟100’,其次是‘洛阳4号’,‘长脖黄’含量最低;类西柏烷类和类胡萝卜素类含量最高的是‘洛阳4号’,其次是‘中烟100’。不同基因型的评吸评价结果是：中下部叶片以‘中烟100’评吸总分最高,其次是‘洛阳4号’,‘长脖黄’较差;上部叶片以‘洛阳4号’评吸总分最高,其次为‘中烟100’,‘K326’较差。豫西地区适合主推‘中烟100’和‘洛阳4号’品种,合理搭配‘云烟202’、‘K326’,淘汰‘长脖黄’。     

苹果白粉病抗性评价

苹果白粉病是危害苹果的重要病害之一。本试验通过人工喷雾接种苹果白粉病的方法,研究了10个不同苹果品种对白粉病的抗病性。抗性鉴定结果表明,‘鸡冠’、‘早嘎啦’、‘美国八号’、‘伏花皮’和‘华红’发病轻,属于抗病品种,‘信浓红’、‘富士’、‘秦阳’和‘国光’发病较重,属于感病品种,且幼嫩的叶子较成熟的叶片容易发病。本试验结果为抗白粉病的机制研究、培育抗病新品种等提供了重要依据。     

‘天达2116’提高冬小麦抗低温冷害生理特性的研究

为了探讨‘天达2116’对冬小麦膜稳定性的影响,通过室内栽培冬小麦幼苗,在人工气候箱内模拟低温(2℃)冷害条件,冷害前后对冬小麦叶片喷施‘天达2116’,采用紫外-可见分光光度法、NBT光还原法、硫代巴比妥酸比色法、Bradford法和蒽酮比色法分别测定冬小麦叶片叶绿素含量、过氧化物歧化酶(SOD)活性、丙二醛(MDA)含量、可溶性蛋白含量和可溶性糖含量,研究‘天达2116’对冬小麦抗低温冷害生理生化指标的影响。结果表明,‘天达2116’对低温冷害冬小麦叶片叶绿素含量和SOD活性的影响差异显著;低温冷害处理后冬小麦叶片MDA、可溶性糖含量增加,经‘天达2116’处理后可使两项指标均显著下降;随着冷害时间的延长,MDA、可溶性糖含量均呈现先下降后上升的趋势;低温冷害处理对冬小麦叶片可溶性蛋白含量影响较小。‘天达2116’对冬小麦叶片的生长状况起到积极的保护作用,能够提高冬小麦抗低温冷害的能力。     

10个烤烟新品种田间性状及叶片组织结构的比较

通过对丽江市引进的10个烤烟新品种（‘云烟98’、‘云烟110’、‘云烟113’、‘云烟114’、‘云烟115’、‘云烟202’、‘H3’、‘MSK326’、‘T29’和‘XYN87’）田间性状及烟叶组织结构的比较,为当地选择优良品种种植提供参考。结果表明：（1）10个烤烟新品种均能较好地适应当地的生态条件和栽培措施,品种‘T29’生育期明显长于其余品种,它与‘XYN87’、‘H3’的农艺性状表现最好;（2）‘云烟110’、‘XYN87’、‘MSK326’和‘H3’等品种的叶片组织结构表现最优,‘云烟113’和‘T29’表现最差;（3）各品种叶片组织结构中,组织比变异系数最大,达26.51%,叶厚和栅叶比最小,分别为15.93%和13.42%,栅栏组织厚度与叶片厚度、组织比、栅叶比呈极显著正相关,与海绵组织厚度成显著正相关。通过相关栽培措施可以使农艺性状表现好的品种烟叶组织结构得到改善。     

重庆不同品种葡萄营养成分和原花青素含量分析

为了选出综合表现最好、最适合重庆地区栽培的葡萄品种,以重庆地区主栽的‘蜜莉’、‘巨峰’、‘夏黑’和‘巨玫瑰’等葡萄品种为材料,测定果实的物理指标以及糖、酸、维生素C、可溶性固形物等品质指标和原花青素含量,为品种选择提供依据。实验结果表明：‘巨峰’总糖含量最高,‘巨玫瑰’含量最低;总酸‘蜜莉’含量最高,‘巨玫瑰’含量最低;‘夏黑’维生素C含量最高,‘蜜莉’含量最低;可溶性固形物‘夏黑’含量最高,‘巨峰’含量最低。果皮和果汁原花青素含量是‘巨玫瑰’>‘夏黑’>‘巨峰’>‘蜜莉’,种子原花青素含量是‘巨玫瑰’>‘巨峰’>‘蜜莉’,‘夏黑’为无核品种。同一品种不同部位原花青素含量是种子>果皮>果汁。     

梨果实生长期矿质元素变化研究

为了进一步明确矿质元素对梨果实品质的影响,并为梨施肥和品质调控提供理论依据,以香梨、‘早酥’梨和‘新梨7号’为材料,研究了在果实生长发育期间,Ca、Mg、Fe、Mn、Zn、Cu元素的含量变化。结果表明：‘新梨7号’、香梨和‘早酥’梨果实中果实中Ca、Mg含量随果实生长逐渐降低,而Cu和Mn元素含量逐渐升高,Fe、Zn波动较大。其中香梨果实Ca、Mg、Mn、Cu含量高于‘早酥’梨和‘新梨7号’果实,‘早酥’梨果实中Ca、Mg、Fe、Mn含量高于‘新梨7号’。果实生长发育期间,对3个梨品种果实各矿质营养元素含量进行比较,变化形式一致,均为：Ca>Mg>Fe>Zn>Cu>Mn。     

木薯不同生育时期内源激素含量变化研究

为探讨木薯块根淀粉含量不同的品种不同生育时期内源激素的变化,以‘华南124’和‘辐选01’2个块根淀粉含量不同的木薯品种为材料,分别对其不同生长发育时期的块根、茎杆及叶片中内源吲哚乙酸(IAA)、赤霉素(GA3)、玉米素(ZR)、脱落酸(ABA)的含量变化进行了研究。结果表明：2个木薯品种块根、茎杆及叶片中IAA、GA3和ZR 3种激素的含量变化趋势基本一致,在块根中这3种激素均呈先上升后下降的变化趋势,茎杆中这3种激素的含量均呈先下降后上升的变化趋势,叶片中这3种激素的含量均为逐渐下降的变化趋势;而ABA含量的变化不同于IAA、GA3和ZR,其在整个生育期间呈不断上升的变化趋势。不同品种内源激素含量变化不同,块根IAA含量生育前中期,‘辐选01’高于‘华南124’,后期两者差异不大。块根GA3含量生育前期,2个品上差不大,中后期‘华南124’高于‘辐选01’。块根ZR含量前期两个品种相差不大,中期‘辐选01’高于‘华南124’,后期‘华南124’高于‘辐选01’;块根ABA含量整个生育期‘华南124’高于‘辐选01’,但叶片ABA含量则相反,‘辐选01’高于‘华南124’。木薯不同生育时期块根、茎杆及叶片的内源激素IAA、GA3、ZR、ABA含量变化不同,块根淀粉含量不同的品种内源激素含量变化也不同。     

‘苏帅’苹果表观遗传变异分析

[目的]为探索杂交品种‘苏帅’表观优良性状遗传的生理机制。[方法]以杂交品种‘苏帅’和父本‘金冠’、母本‘印度’为材料, 通过分析 ‘苏帅’和‘金冠’、‘印度’等苹果品种的节间数、节间长度以及叶片内源激素、果实可溶性固形物、可滴定酸、叶绿素的含量; 采用石蜡切片法、扫描电镜等方法比较其叶片结构, 测定了叶片光合气体交换参数。[结果]结果表明, ‘金冠’和‘印度’的节间长度显著大于‘苏帅’苹果的节间长度,‘苏帅’苹果叶片叶绿素相对含量显著高于‘金冠’和‘印度’; 果实可溶性固形物含量与‘金冠’虽然没有显著性差异, 但可滴定酸的含量明显高于‘金冠’苹果; ‘苏帅’苹果内源激素脱落酸(ABA)、赤霉素(GA)、吲哚－3－乙酸(IAA)、玉米素核苷(ZR)与‘金冠’和‘印度’相比均呈显著差异。‘苏帅’苹果叶片下表皮气孔长度大于‘印度’, 且差异极显著,但小于‘金冠’,气孔宽度显著宽于‘印度’,与‘金冠’苹果没有明显差异, ‘苏帅’苹果气孔密度极显著小于‘金冠’和‘印度’;‘金冠’和‘印度’栅栏细胞组织排列较紧密, 栅栏组织和海绵组织分界限明显,而‘苏帅’苹果的栅栏组织细胞排列相对杂乱,细胞大小也不一致, 与海绵组织界限不明显; ‘苏帅’苹果叶片、上下表皮、栅栏组织及海绵组织厚度显著高于‘金冠’和‘印度’,栅栏组织和海绵组织比值也显著高于‘金冠’和‘印度’。[结论] ‘苏帅’苹果与父母本相比表现出节间短、叶片变厚、光合作用增强等性状多样性, 为苹果生产提供了新品种,也为苹果新品种的培育提供了珍贵的种质资源。     

Effects of preharvest nitric oxide treatment on ethylene biosynthesis and soluble sugars metabolism in ‘Golden Delicious’ apples

In order to examine the influence of preharvest nitric oxide (NO) treatment on ethylene biosynthesis and soluble sugar metabolism in ‘Golden Delicious’ apples, apple trees were sprayed with 50 μM sodium nitroprusside (SNP) (a donor of NO) 14 days before harvest. The results indicated that preharvest SNP treatment can increase the NO content and the NOS activity in apple fruit, therefore, delay the accumulation of ethylene due to its inhibition on the activities of 1-aminocyclopropane-1-carboxylate synthase (ACS) and 1-aminocyclopropane-1-carboxylate oxydase (ACO). Fructose is the main sugar in ‘Golden Delicious’ apple. The synthesis of sucrose was stimulated and the decomposition of sucrose was inhibited by this treatment, thus causing the accumulation of sucrose. We can draw a conclusion that pre-harvest SNP (50 μM) treatment can increase the NO content of fruit during storage, while higher NO content can further regulate fruit ripening through its effect on ethylene and sugar metabolism in ‘Golden Delicious’ apple fruit during storage at 18 °C.     

华南特色大棚夏季微域环境变化研究

为了解华南特色大棚夏季微域环境的变化特点,研究了防雨棚和防虫网棚2种设施内外的气温和相对湿度的变化特征。结果表明,设施内外日平均气温差异小,白天设施内升温快,气温比露地稍高,但设施内外最高气温差异在2℃以下,晚间设施内外气温相近;设施内外相对湿度差异较大,防雨棚的相对湿度白天高、晚上高,防虫网棚白天低、晚上高,露地则是白天低、晚上低;设施内外最大相对湿度差异小,防雨棚最小相对湿度明显高于防虫网和露地。因此,防雨棚和防虫网棚温度与外界差异小,均适合华南地区夏季蔬菜栽培,但防雨棚的防雨水效果更佳,相对湿度更稳定,防虫网棚的防虫效果好,可根据种植需要选择合适的设施。     

Microspore Embryogenesis Induced by Low Gamma Dose Irradiation in Apple

Flower buds and extracted anthers of two apple genotypes, ‘Golden Delicious’— a previously known non-androgenic genotype — and ‘Topred’— a known androgenic genotype —, were irradiated by gamma-rays at doses ranging from 5 to 20 Gy, after 0 to 5 weeks of cold pre-treatment (3 °C). When the extracted anthers were irradiated, both microspore embryogenesis and callogenesis were limited for the two genotypes. For ‘Golden Delicious’, androgenic embryogenesis was induced from the flower buds irradiated at 10 to 20 Gy and after 3 to 5 weeks of cold pre-treatment. For ‘Topred’, androgenic embryogenesis was slightly improved after flower bud irradiation at 5 to 10 Gy following cold pre-treatment from 0 to 3 weeks; it was limited after 5 weeks of cold pre-treatment.     

Investigation and genetic mapping of a Glomerella leaf spot resistance locus in apple

Apple Glomerella leaf spot (GLS) is a severe fungal disease that damages apple leaves during the summer in China. Breeding new apple varieties that are resistant to the disease is considered the best way of controlling GLS. Fine mapping and tightly linked marker are critically essential for the preselection of resistant seedlings. In this study, a population of 207 F₁ individuals derived from a cross between ‘Golden Delicious’ and ‘Fuji’ was used to construct a fine simple sequence repeat (SSR)‐based genetic linkage map. The position of R_gls, a locus responsible for resistance to GLS, was identified on apple linkage group (LG) 15 using SSR markers CH05g05 and CH01d08, which was adapted from a published set of 300 SSR markers that were developed using the bulked segregant analysis (BSA) method. These two SSR markers flanked the gene, and its recombination rate was 8.7% and 23.2%, respectively. A total of 276 newly developed SSR markers around the target region and designed from the genome apple assembly contig of LG15 were screened. Only nine of these were determined to be linked to the R_gls locus. Thus, a total of 11 SSR markers were in linkage with R_gls, and mapped at distances ranging from 0.5 to 33.8 cM. The closest marker to the R_gls locus was S0405127, which showed a genetic distance of approximately 0.5 cM. The first mapping of the gene R_gls was constructed, and the locations of the 11 effective primers in the ‘Golden Delicious’ apple genome sequence were anchored. This result facilitates better understanding of the molecular mechanisms underlying the trait of resistance to GLS and could be used in improving the breeding efficiency of GLS‐resistant apple varieties.     

Allelic polymorphism and inheritance of MdACS1 and MdACO1 genes in apple (Malus × domestica Borkh.)

The allelic polymorphism and inheritance of MdACS1 and MdACO1 genes were analysed in 28 apple cultivars, which were derived from reciprocal crosses of the following parental pairs: ‘Golden Delicious’ × ‘James Grieve’, ‘Golden Delicious’ × ‘Jonathan’, ‘Cox's Orange Pippin’ × ‘Golden Delicious’, ‘Cox's Orange Pippin’ × ‘Jonathan’. Polymorphisms were detected by PCR and the use of two restriction enzymes (BamH1 and RsaI). In addition, new primers were designed for the further discrimination of MdACO1 alleles. Two alleles of MdACS1 gene (MdACS1‐1 and MdACS1‐2) and three alleles of MdACO1 gene (a, b and c) were detected. Cloning and sequencing of MdACO1 alleles confirmed a high conservation and some differences within the coding regions and helped to reconcile between different numbering systems. Observed segregations confirmed that alleles a, b and c belonged to the MdACO1 gene. It is apparent that polymorphisms within the MdACS1 and MdACO1 genes could aid cultivar genotyping and identification and, furthermore, that the MdACS1‐2/2 genotype is correlated with a long apple storage life.