栽植密度对人参果大小及产量的影响

为探索人参果不同栽植密度对产量和单果重的影响，进行了不同栽植密度试验，取得了理想的效果，为实现优质、高产、高效益提供了最佳栽植密度。     

乙烯利诱导菠萝成花过程中FT基因的克隆与表达分析

【目的】克隆菠萝AcFT基因并研究其表达模式,为深入研究该基因在乙烯利诱导菠萝成花中的功能奠定基础。【方法】从菠萝基因组数据库中获得AcFT基因全长序列,设计全长引物,克隆两个AcFT基因,分别命名为AcFT1和AcFT2,对基因序列进行生物信息学分析;通过qRT-PCR探究乙烯利处理后菠萝AcFT基因在不同组织、时间下的表达模式。【结果】AcFT1和AcFT2分别编码178和177个氨基酸,两者均含有PBP结构域,具有PEBP家族典型结构特征。实时荧光定量PCR分析结果显示,AcFT1和AcFT2都具有组织表达特异性,在茎和叶中相对表达量较高;乙烯利处理后,AcFT1和AcFT2在茎和叶中的表达具有相反的趋势,其中AcFT2明显受到乙烯利上调,呈现先上升后下降趋势,AcFT1则显示为先下降后上升。乙烯利处理后1 d,茎尖组织AcFT2的表达水平显著上升,相对表达量约为对照的178倍,而AcFT1则明显下调;乙烯利处理后31 d,AcFT2在茎尖中的表达水平达到最大值,约为对照的408倍,但AcFT1却处于极低水平。【结论】克隆得到2个AcFT基因,AcFT2基因在乙烯利处理后1 d及随后的花芽分化时期高度表达,表明AcFT2在响应外源乙烯利信号诱导菠萝成花过程中发挥重要作用。     

Effect of ethephon (2-chloroethylphosphonic acid) on the fruit ripening characters of rabbiteye blueberry

Effect of ethephon (2-chloroethylphosphonic acid) application on rabbiteye blueberry fruit quality during the growth period was investigated. Ethephon treatment stimulated the decrement of titratable acidity, anthocyanin accumulation and fruit softening 4 days after treatment and the promoting effects continued through the investigation period. The ripening promotion effect of ethephon on total soluble solids content was observed only 8 days after treatment. Ethephon treatment did not affect the fruit enlargement during the investigation period. From these results, it is concluded that ethephon application for rabbiteye blueberry promote the fruit ripening, but the stimulatory effects of ethephon on fruit ripening were different in degree on each ripening characters.     

Scale-dependent seasonal habitat selection by jaguars (Panthera onca) and pumas (Puma concolor) in Panama

Landscape Ecology - Few habitat modeling studies consider multiple spatial or temporal scales; less identify the operative scale of an organism's response to predictor variables. Optimizing...     

Investigations on the use of (2-chloroethyl) phosphonic acid (ethephon,CEPA) for the control of biennial bearing in mango

Biennial bearing is a serious economic problem facing mango growers. In the past it has been attributed to the lack of new growth and insufficient carbohydrate and nitrogenous reserves following a year of heavy cropping. The results of our studies conducted over a period of 4 years have shown that ethephon (200 ppm) could be used to induce heavy flowering and fruiting during the “off year” in the notedly biennial bearing cv. ‘Langra’. The spray applications of ethephon should be started during September and continued four to five times at 15–20 days interval. Higher concentrations of ethephon, viz. 500, 1000 and 2000 ppm, induced moderate to heavy leaf abscission in the experimental trees. Consecutive applications of 200 ppm ethephon for a period of 3 years did not show any decline in the vigour and yielding ability of the treated ‘Langra’ mango trees.     

Flowering in pineapple as influenced by ethephon and its combinations with urea and calcium carbonate

An investigation was carried out to increase the efficacy of ethephon by combining it with urea and calcium carbonate for induction of flowering in pineapple, with the main objective of lowering the concentration of ethephon. Ethephon at a concentration as low as 25 ppm in combination with urea (2%) and calcium carbonate (0.04%) was able to induce more than 90% flowering after 50 days of treatment. Addition of either urea or calcium carbonate increased the effectiveness of ethephon for induction of flowering. Ethephon treatments were found to be markedly superior to planofix and the control. In the case of the control, plants started flowering 250 days after treatment and completed it after 340 days. Apart from earlier flowering, ethephon treatments resulted in uniform ripening, and harvests were complete within 10 days, whereas in the control harvests continued for about 70 days. The increased efficacy of ethephon at a lower concentration for induction of flowering, with the addition of urea and calcium carbonate, is of great significance as this will lead to decreased costs and increased commercial use.     

乙烯利和氯吡脲在黄瓜制种中的应用

为了提高黄瓜杂交制种种子产量,结合植物生长调节剂在蔬菜上的应用实践,研究了乙烯利和氯吡脲对黄瓜杂交制种种子产量和质量的影响。结果表明,150～250 mg·L~(-1)乙烯利于母本4叶1心时喷施效果较佳,种子产量提高了45.8%;3～6 mg·L~(-1)氯吡脲于授粉后浸蘸瓜,效果较佳,产量增加30.0%,化瓜率由对照的34.1%降低到8.0%。乙烯利和氯吡脲的研究应用可为黄瓜制种实践提供技术支撑。     

Microtuberization of Andean potato species (Solanum spp.) as affected by salinity

The effects of NaCl stress on in vitro tuberization of potato species were studied. Three species of potato (Solanum tuberosum L., S. curtilobum Juz. and Bukasov, and S. juzepczuckii Bukasov) differing in frost resistance were subjected to 0, 25, 50, 75, and 100 mmol l⁻¹ NaCl. Stolon growth and microtuberization were evaluated. The in vitro induced microtubers were characterized with respect to their carbohydrate composition by measuring reducing, non-reducing, total soluble sugars and starch contents. Tuberization and stolon growth, expressed by stolon height or fresh mass, were significantly affected by salinity. The highest saline level (100 mmol l⁻¹ NaCl) completely inhibited tuber development in all species, but not stolon growth. Stolon growth for sensitive species (S. tuberosum) had a significant decrease, whereas both frost tolerant species (S. juzepczuckii and S. curtilobum) tended to increase stolon length with increasing saline levels. Salinity differentially influenced sugar accumulation among potato genotypes. The starch levels in both, S. curtilobum and S. juzepczuckii, remained constant under all salt levels, whereas starch increased in S. tuberosum microtubers.     

SlGLK2转录因子在番茄品种Heirloom果实中的功能及变异分析

Goldern2-Like(SlGLK2)基因是调控未成熟果实叶绿体发育重要的转录因子。番茄(Solanum lycopersicum)未成熟果实中叶绿体对成熟果实的糖类、风味物质积累和提高番茄品质具有一定的作用。Heirloom品系作为优异的种质资源,在果实颜色、大小、形状和风味等方面有很大差异。以32个Heirloom品种为研究材料,通过表型调查研究果实表型性状,检测果实不同部位和不同发育时期叶绿素含量,筛选20个Heirloom品种克隆SlGLK2基因和启动子序列,运用荧光定量PCR分析调控果实叶绿体发育的相关基因,从而分析基因间的调控关系,以期研究SlGLK2转录因子对Heirloom品种叶绿体发育的影响。结果表明:含有SlGLK2基因的品种,未成熟果实拥有深绿色果肩,其不同发育时期绿色果实果肩的叶绿素含量明显高于果实底部。在SlGLK2基因上游非编码区和编码区共发现21个单核苷酸多态性(SNPs),经聚类分析发现,部分SNPs与未成熟果实的表型相关。果实叶绿体发育相关基因的表达分析表明TKN2、TKN4和在番茄果实的果肩部表达量明显高于果实底部,且TKN2、TKN4位于SlGLK2上游并调控SlGLK2基因的表达。     

不同茄子品种幼苗耐热性研究

以45 ℃/36 ℃（昼/夜）的温度对4个茄子品种进行胁迫处理,研究了高温胁迫对茄子的热害指数、电解质渗透率、SOD活性、MDA含量及叶绿素荧光参数的影响。结果表明,高温处理后,茄子热害指数、电解质渗透率及MDA含量显著上升,耐热品种上升幅度低于不耐热品种;SOD活性显著降低,恢复2 d后耐热品种06-E417和紫妃1号的SOD活性比处理前上升了20.3 %和20.7 %,不耐热品种则没有表现这种趋势。高温胁迫后,茄子Fv/Fm、Fv/Fo、ΦPSⅡ、qP、ETR及Fv’/Fm’均显著降低,耐热品种降低的幅度低于不耐热品种,表明在高温胁迫后耐热品种具有较高的光系统Ⅱ活性。     

马铃薯GLDH基因的克隆及序列分析

 以马铃薯品种‘Favorita’叶片中的cDNA为模板,采用RT-PCR、巢式PCR、3′RACE和5′RACE技术,获得了L–半乳糖酸–1,4–内酯脱氢酶（EC 1131213,GLDH）基因cDNA 2 563 bp的全长序列,命名为StGLDH（GenBank：FJ755844）。序列分析表明,该基因编码区长1 773 bp,编码590个氨基酸,与其他植物GLDH氨基酸序列具有很高的同源性,尤其与番茄、辣椒、烟草GLDH 氨基酸序列具有90.6% ~ 95.9%的同源性。荧光定量分析表明,该基因在马铃薯不同器官中均有表达,在幼叶和功能叶中表达量最高,在茎中表达量最低;除匍匐茎外,其它器官中抗坏血酸（ascorbic acid,AsA）含量与StGLDH的表达高度一致。     

Pollinator selection in kiwifruit (Actinidia deliciosa)

SUMMARY

Pollinator performance was evaluated in kiwifruit to select pollinators for cv. Hayward adapted to the cultural conditions of southern Europe. Flowering time was determined in forty male seedlings. From, these, nine were selected for having a flowering period overlapping with ‘Hayward’. In these nine males, as well as in the commercial pollinators‘Matua’ and Tomuri’, the production of pollen was studied over two years, investigating pollen quantity through flower density and pollen production per flower. Likewise, in vitro pollen viability and its in vitro germination were recorded to study pollen quality. Finally, in vivo pollen performance was studied through fruit set and fruit characteristics in controlled hand pollinations. Two males have been selected with a flowering period coincident with ‘Hayward’, which produce more than twice as much germinable pollen than commercial pollinators. Whilst there were no significant differences in pollen quality or in fruit production, clear differences existed for pollen quantity in terms of both flower density and pollen production per flower. As pollen quantity, together with flowering time, can be easily evaluated at an early stage, this is encouraging for future selection ofkiwifruit pollinators.     

Characterisation of cultivated breeding lines of eggplant (Solanum melongena L.) and related wild Solanum species from India

Immature fruit of cultivated species of eggplant (Solanum melongena L.) are commonly used as a summer vegetable in India. Rich morphological variation exists among the cultivated species of eggplant in different growing regions of the country. We have characterised 24 breeding lines of Solanum spp., including 20 eggplant cultivars and four wild species of eggplant, based on 13 morphological characters using Mahalonabis D² statistics. All 24 breeding lines of Solanum spp., including the 20 eggplant cultivars and four wild species, were grouped into four clusters by agglomerative clustering. Cluster II and Cluster IV contained the most accessions (eight each), while Cluster I and Cluster III had four accessions each. The highest inter-cluster (D²) distance (158.33) was observed between Cluster I and Cluster II, followed by Cluster I and Cluster III (108.48), and Cluster II and Cluster IV (102.96), which indicated that accessions in Cluster I and Cluster II were more divergent than those in the other clusters. The highest intra-cluster distance (5.80) was observed in Cluster IV, with eight genotypes, and the lowest intra-cluster distance (2.21) was observed in Cluster II, also with eight genotypes. The intra-cluster distances in all four clusters were lower than the inter-cluster distances, which indicated that genotypes within the same cluster were closely related. Genotypes in Cluster IV had the maximum number of flowers per cluster (3.63), the highest number of fruit per cluster (3.25), and number of fruit per plant (208.63), which revealed that genotypes could be selected from Cluster IV for these characters. The first three principal components (PC1, PC2, and PC3) accounted 73.99% of the total variation among the 24 genotypes. These phenotypic data increase the feasibility of prioritising breeding lines in a crossing programme based on the uniqueness of their desirable morphological traits.     

茄子抗青枯病基因的RAPD标记研究

 为探明茄子抗青枯病的遗传机制, 以高感青枯病品种北京六叶茄064, 高抗青枯病半栽培种马来西亚S3及其F₂ 代为材料, 用RAPD技术对供试材料的抗青枯病基因进行了研究。结果表明: 通过300个随机引物的PCR扩增分析, 发现15.6%的引物在双亲间表现出多态性, 找到了一个与茄子抗青枯病亲本S3中的抗病基因紧密连锁的分子标记S264₇₈₀ (该引物的碱基序列为CAGAGCGGA) , 该标记与S3的抗病基因的交换值为4.32% , 遗传距离为4.33 cM。     

辐射诱变和芽变柑橘品种(系)的AFLP分析

为了对广东省近年来新选育的16个60Co-γ辐射诱变和芽变柑橘优良品系(株系)进行遗传差异分析,应用AFLP技术,对3个亲本和16个辐射诱变和芽变的柑橘品种(系)进行了遗传差异分析。从64对引物中筛选出9对多态性高、分辨能力强的引物进行分析,结果表明:(1)与各自的亲本相比,供试16个辐射诱变和芽变的柑橘变异类型的遗传基础均已经发生了不同程度的变化。(2)利用引物EcoRⅠAAG+MseⅠCTT绘制供试样品的AFLP指纹图谱,并根据各自的差异带或特征带区分了19个柑橘试材。(3)对AFLP扩增结果进行聚类分析,根据相似系数0.77的水平可将19个样品分为4组。红江橙品系中的华青1号与亲本间的相似性系数仅为0.647 7,可将其单独划为一组。可为柑橘新品种选育研究的早期鉴定提供参考依据。     

茄子青枯病抗性的遗传分析

 选用6个对青枯病具有不同抗性水平的茄子自交材料，按完全双列杂交设计，配制36个组合(包含亲本自交)。苗期人工接种鉴定各组合抗性并计算病情指数，采用Grifmg方法I及Hayman方法对抗性配合力方差进行分析，估计相关遗传参数。结果表明，茄子对青枯病的抗性遗传规律符合“加性一显性”效应模型。遗传效应中同时存在加性效应、显性效应和反交效应，但以加性效应为主。茄子对青枯病的抗病性表现隐性，感病性表现部分显性。茄子对青枯病的抗性遗传较为复杂，由多个微效基因、较少的主效基因和细胞质基因共同控制。     

Preferential accumulation of orange-colored carotenoids in Ponkan (Citrus reticulata) fruit peel following postharvest application of ethylene or ethephon

To avoid winter frost, Ponkan (Citrus reticulata Blanco cv. Ponkan) fruit in Zhejiang Province, China, is frequently harvested early, while chlorophylls are still present in the peel. Postharvest degreening of Ponkan fruit, through either ethylene fumigation or ethephon dipping, was carried out to study the effects of both treatments on color development and carotenoid accumulation. An earlier and deeper orange color development after treatments was indicated by a decline in hue angle (H°) and an increase in the citrus color index (CCI). Total carotenoid content increased, while chlorophyll content decreased during storage at 10 °C, and these changes were accelerated by both treatments. The treatments stimulated preferential accumulation of carotenoids with orange color (β-carotene and β-cryptoxanthin) while reducing the abundance of carotenoids with yellow color (lutein, violaxanthin and 9-cis-violaxanthin). Gene expression of β-carotene hydroxylase (BCH) was inhibited by both treatments, which could be related to the changes in composition of these differently colored carotenoids.     

马铃薯栽培种与野生种叶肉细胞融合及体细胞杂种鉴定

 以马铃薯栽培种Solanum tuberosum ‘中薯二号’的无性系3 # 、8 # (2n = 48) 和二倍体野生种Solanum chacoense (2n = 24) 的无菌苗为原生质体来源, 比较了PEG (聚乙二醇) 融合和电融合两种方式马铃薯原生质体融合效果的影响。结果显示, 两种融合方式对细胞的融合率没有显著差异, 但电融合的细胞植板效率和愈伤组织分化能力均显著高于PEG融合法。在早期挑选的生长旺盛的愈伤组织再生的100个株系中, 经RAPD 标记检测有97 个系为体细胞杂种。杂种植株经流式细胞仪倍性分析表明, 52.6 %为六倍体, 14.4 %为八倍体, 14.4 %为非整倍体, 18.6 %为混倍体。叶绿体SSR 引物NTCP29 用于细胞质重组检测, 结果显示, 体细胞杂种中叶绿体具有偏亲现象, 大多数杂种只含有单一亲本的叶绿体类型, 只有16.5 %株系为叶绿体重组的杂种植株。     

The effect of ethephon on the growth and development of Liatris spicata

Summary

The first experiment studied the effect of applying ethylene biosynthesis regulating compounds (ethephon 1000 ppm, silver thiosulphate 0.4 mM and cobalt chloride 5 mM) on the growth and development of Liatris spicata cv. Callilepis. The results pointed to the important growth retardant properties of ethephon and the increased number of flowering stems per corm which could be obtained by pre-planting application. A second experiment aimed to optimize ethephon treatment in Liatris by applying the growth retardant in different concentrations (100, 700, 1300, 1900 and 2500 ppm) at three stages of development: stage I (pre-planting), stage II (immediately after the formation of basal leaf rosette) and stage III (when the main shoot began its rapid longitudinal growth). Besides confirming the effects produced by ethephon in the first experiment, the results suggested that the application of high ethephon concentrations (1900 and 2500 ppm) during stage II of growth produced many miniature flowering stems coming from the principal or secondary shoot.     

Anatomical and growth effects of ethephon on hyacinths and Narcissus during greenhouse forcing

‘Blue Blazer’ hyacinths and ‘Jack Snipe’ Narcissus were sprayed to run-off with 2000 mg l⁻¹ ethephon when average leaf length was 10 cm. Ethephon reduced the length of the flower scape of ‘Blue Blazer’ by 20% at “bud” stage of development, and by 28% at full flower. No effect on date of flowering was observed. The floral scape length reduction of ‘Jack Snipe’ was 27% at the “goose-neck” stage and 25% at full flower. Anatomical and stereological examinations revealed significant cellular and structural differences between treated and untreated plants of both species. The cell sizes of the treated plants were smaller and the intercellular space sizes were decreased. Endodermal cell separation was reduced and pith deterioration was delayed. There was a 20–30% increase in the number of cells in the treated plants; a phenomenon not usually associated with ethephon. Thus, while ethephon normally promotes senescence, in these studies, it enhanced cell division.