Production of fruits with attached flowers in zucchini squash is correlated with the arrest of maturation of female flowers

Summary

Results from two trials carried out under different environmental conditions indicated that the high temperatures reached in greenhouses during the Spring-Summer growing season are the main environmental factor inducing production of zucchini fruits with attached flowers. The fact that the incidence of this characteristic is genotypedependent, with the percentage of fruits with attached flowers varying from 1.4 – 73% among the different cultivars grown during the Spring-Summer season, provides an opportunity for direct counter-selection for this trait in current zucchini squash breeding programmes. High temperatures in the Spring-Summer growing season also induced male-ness in all the cultivars analysed, delaying the production of female flowers, and increasing the number of male flowers on the main stem. Indeed, those flowers that remained attached to harvested zucchini fruits were transformed into bisexual flowers, exhibiting different degrees of stamen development, and were arrested as immature, closed floral buds. A detailed analysis of the maturation and abscission times in female and male flowers of different zucchini cultivars indicated that, although abscission time did not differ, maturation time was longer in male than in female flowers. By comparing sexual expression in different cultivars in different environments, we concluded that inhibition of female flower bud maturation occurs concomitantly with a delay in flower abscission, a process accompanied by the conversion of the female bud into a bisexual bud. Given that Spring-Summer conditions promote the maturation of both female and male flowers, and that the arrest of female flower maturation and abscission are associated with floral sex determination, it is possible that the arrest of female flower maturation is not directly induced by high temperatures, but is mediated instead by hormones such as ethylene or gibberellins.     

Controlling the growth and development of rose plants after planting

The effects of pinching and lateral bud removal (deshooting) on the development of structural shoots, the number of flowers, and the average flower stem length in young rose plants were examined, using the cultivars ‘Baccara’, ‘Sonia’ and ‘Belinda’. The effect of deshooting on flower yield varied with each cultivar. It did not affect the number of ‘Baccara’ flowers, but increased ‘Sonia’ and ‘Belinda’ flower production by 50% and 75%, respectively. Leaving flowers to bloom out on plants before the start of commercial harvest resulted in a decrease in the length of the flower stems and also reduced the beneficial effect of deshooting on flower yield. Deshooting enhanced structural shoot formation (“bottom breaks”). Pinching flower buds of structural shoots increased the number of ‘Baccara’ flowers in comparison with pruning these shoots to 40–60 cm, as in common practice. Deshooting of the structural shoots of ‘Sonia’ and ‘Belinda’ increased the number of flowers in both cultivars.     

Flower initiation and development in the glasshouse rose

The initiation and development of a rose flower has been divided into a sequence of ten developmental stages. These numbered stages were used as a standard scale to follow flower development in various treatments for a number of cultivars. Flower initiation took place soon after stem extension occurred in a previously inactive bud, usually about two weeks after removal of the marketable flowering shoot above the bud. All actively growing buds appeared to initiate flowers, indicating that the abnormality known as ‘blind-wood’ is caused by the subsequent abortion of developing flower buds. There were seasonal differences in the rates of development which varied considerably between cultivars. The scale of development outlined here may provide a useful criterion for the selection of cultivars for year-round production programmes.The importance of light level as a factor determining development and productivity is discussed and some comparisons are made between rates of development with continuous production and with a period of inactivity. It is concluded that the latter technique does not enhance development and if growth is resumed too slowly, development may be delayed by the lower temperatures and abnormalities may occur.A correlation between apical development and apical size is demonstrated.     

乙烯对不同切花月季品种开花和衰老的影响

 以研究乙烯在月季切花开花和衰老进程中的作用为目的, 以14 个切花月季品种为试材, 首先探讨了乙烯和乙烯抑制剂处理对切花开花和衰老进程的影响。结果表明: 乙烯和乙烯抑制剂处理对不同乙烯变化类型切花月季品种的开花和衰老进程有不同的影响效果, 类似非跃变型切花‘唐娜小姐’表现出典型的非跃变型切花的特征, 但是类似跃变型品种和类似末期上升型品种却有复杂的表现, 分别表现为促进、抑制和不敏感。在此基础上, 探讨了乙烯和乙烯抑制剂处理对类似跃变型品种‘萨蔓莎’和‘红衣主教’、类似非跃变型品种‘唐娜小姐’以及类似末期上升型品种‘黄金时代’乙烯生成量的影响。结果表明: ‘萨蔓莎’和‘红衣主教’分别表现为乙烯的自我催化和自我抑制。乙烯和乙烯抑制剂处理对类似非跃变型品种‘唐娜小姐’的乙烯生成量无影响。类似末期上升型品种‘黄金时代’, 表现为典型的负反馈调节。这些结果说明月季切花对乙烯的反应非常复杂, 在开花衰老进程中呈现不同乙烯变化类型的品种对乙烯的反应差别很大, 不能简单地根据内源乙烯生成量的变化动态对不同的切花月季品种进行类型划分。     

Fruit set is inversely related to flower and fruit weight in olive (Olea europaea L.)

Fruit weight is strongly correlated to ovary weight in olive as big-fruited cultivars have larger ovaries and flowers at bloom. We tested the hypothesis that larger ovaries imply stronger sinks and therefore reduce fruit set, expressed as number of fruits. Flower/fruit load per centimeter of shoot was assessed every month from flowering to harvest, on sample shoots of many different olive cultivars differing in fruit size. Data were taken for two years: 2007 and 2008. Additionally, in 2008, a fruit thinning experiment was carried out by leaving a single fruit per shoot, to assess the maximum potential fruit weight achievable by each cultivar. Results indicated that fruit size was mostly genetically determined as thinned fruits of small-fruited cultivars, although bigger than control fruits, never got as big as fruits from large-fruited cultivars, confirming that large ovaries are a prerequisite for large fruits. Among all cultivars, the number of flowers per inflorescence, the number of inflorescences, and the number of flowers per centimeter of shoot were not correlated to average flower weight while total flower mass per centimeter of shoot was positively correlated to average flower weight (i.e. large flowered/fruited cultivars had greater total flower mass). However, one month after bloom and thereafter, all parameters were negatively and exponentially correlated with fruit average weight across cultivars, except fruit mass per centimeter of shoot which was generally not correlated to fruit average weight, except in one year, at harvest, when fruit mass per centimeter of shoot was positively correlated to fruit average weight. These results suggest that fruit set is a consequence of, and inversely proportional to flower/fruit size in olive.     

Inflorescence architecture of olive

The influence of flower position on the inflorescence on opening day, gender, and petal persistence was studied in three olive cultivars: Manzanillo, Mission, and Frantoio. In each cultivar, 45 inflorescences were checked every morning from flower opening to petal fall. Perfect flowers opened mainly in the beginning of the flower opening period, and staminate flowers opened later. Flower position on the inflorescence had a highly significant effect on the opening day in all cultivars. Terminal flowers and the flowers located on the primary branches opened earlier than the flowers located on the secondary branches. Flower position had also a highly significant effect on gender in Manzanillo and Mission. In Manzanillo, the secondary branches had fewer perfect flowers than the primary branches. In Mission, the secondary branches had no perfect flowers at all. Among the primary branches, the branch arising immediately next to the terminal flower had the latest flowers to open and the lowest percent of perfect flowers. In Manzanillo, perfect flowers had significantly longer petal persistence than staminate flowers. To study flower competition within the inflorescence, the distal half of 120 inflorescences, on which the flowers tend to be perfect, in three trees of Manzanillo were removed about 1 month before full bloom. There was a highly significant effect on the percent of perfect flowers that opened on the proximal half. Flower competition may be a reason for pistil abortion in flowers located on secondary branches.     

The interaction of a dormancy-breaking cold treatment,ancymidol, and ethephon in relation to stem elongation and flower production of Lilium cultivars

Stem elongation of Lilium cultivars ‘Black Beauty’, ‘Jamboree’ and ‘Nutmegger’ was lessened by treating the bulbs with ancymidol (10 p.p.m.) or ethephon (500 p.p.m.). Ancymidol was the more effective inhibitor of stem elongation, although applied at a much lower concentration. Application of the growth regulators prior to a dormancy-breaking cold treatment provided more effective control of stem elongation than post cold-treatment application. The total number of flowers and the number of secondary flowers per stem of ‘Black Beauty’ and ‘Nutmegger’ were increased by treating the bulbs with ancymidol. However, unlike the optimal time for lessening stem elongation, enhancement of flower production was greatest when ancymidol was applied after completion of the cold treatment. Ethephon was unsatisfactory, since it inhibited flower production by ‘Black Beauty’ and ‘Nutmegger’, while ‘Jamboree’ was relatively insensitive to it, as indicated by a lack of inhibition of flower production and a small degree of inhibition of stem elongation.     

蜡梅不同品种和花期香气变化及其花茶适制性

采用顶空固相微萃取结合气相色谱质谱联机分析方法研究了蜡梅4个品种不同开花期的香气成分,并分析了其花茶适制性。结果表明：4个品种主要香气成分为别罗勒烯、罗勒烯、乙酸苄酯和水杨酸甲酯,相对含量之和占总量80%以上。从花蕾期到盛开期,香气成分变化不大,在开花过程中萜烯类化合物相对含量增加,而酯类化合物相对含量减少。随着蜡梅花内被片紫色条纹数量增加,香气中萜烯类和酯类化合物相对含量比值（T/E）减小,而在开花过程中,T/E值增加。花蕾期和盛开期香气相似率达0.990以上,表明开花过程中香气类型变化不大。花蕾期和萎蔫期的鲜花窨制的花茶香气弱,香气和滋味得分低于盛开期,红心品种窨制的花茶幽香不足,香气和滋味得分低于其他品种。在花茶生产上,以选择内被片紫色条纹较少的素心和乔种品种,且盛开的鲜花为宜。     

Flower morphology and number of aubergine (Solanum melongena L.) in relation to fruit load and auxin application

The effect of fruit load and auxin application on the flower morphology and flower number of two aubergine cultivars was investigated under greenhouse conditions. The flowers of plants that did not set fruit showed only minor fluctuations in flower and pistil mass, and in style and anther length. However, when plants were allowed to set fruit by pollination, flower and pistil mass, and style (but not anther) length were significantly reduced during the stage of fruit growth. Style length was also reduced in flowers formed after fruit had been set parthenocarpically by the application of auxin (IAA), but there was no significant effect of IAA on style length in the absence of fruit development. The number of flowers was reduced in the presence of IAA (with or without fruit set), or following fruit set by pollination. It is suggested that fruit load and development affect flower mass and style length of aubergine whereas auxin influences the number of flowers.     

Effect of day and night temperatures during short photoperiods on growth and flowering of Chrysanthemum morifolium Ramat

The effect of day and night temperatures of 10, 14 and 18°C on growth and flowering under short days was studied with six cultivais of chrysanthemum. A high day temperature resulted in earlier flowering and taller stems, but did not influence flower number and final total fresh weight, and only slightly influenced the distribution of fresh matter over stem, leaves and flowers. A high night temperature resulted in earlier flowering, more flowers and reduced stem and leaf weight. It did not affect leaf number and it influenced height and total fresh weight only slightly. Except for height, the day temperature acted independently from the night temperature. The cultivars responded similarly, except for two cultivars which generally did not flower at 10/10,10/14 and 14/10°C D/N. One cul-tivar produced more flowers at 14 than at 18°C.     

露地菊新品种‘繁星粉’和‘火焰’

露地菊新品种‘繁星粉’和‘火焰’是分别以传统应用品种‘袖珍红’和‘秋艳’为母本,与多父本品种混合种植天然杂交获得实生后代,经物理诱变选育而成。‘繁星粉’花色深粉色,平均单株着花426朵。‘火焰’花色橙红色,单花花径大。     

The responses of early-flowering chrysanthemums to daylength

In a study of photoperiod response 30 early (summer)-flowering chrysanthemum cultivars from Britain and Japan reacted as quantitative short-day plants. Both flower bud initiation and development occurred more rapidly in short days (SD) as compared with long days (LD). The early-flowering cultivars differed from late-flowering chrysanthemums in that lateral flower buds, and often the terminal flower buds, develop to anthesis in LD. Internodes were shorter in SD and flowers had fewer florets. There was an increased number and proportion of disc florets in SD in all cultivars except one. Two cultivars, ‘Mezame’ and ‘Pennine Yellow’, closely approached day-neutrality.All cultivars produced fewer leaves in LD on upper lateral shoots than on main stems. Either the presence of the terminal flower bud induces earlier flowering of the upper lateral shoots, or the change which causes the terminal apical meristem to initiate a flower in LD influences the axillary meristem also.SD could be used to speed up the flowering of glasshouse-grown crops of early-flowering cultivars. The advantages and disadvantages which may be associated with treatment at different stages of growth are discussed.     

梨每花序花朵数量与植物激素的关系

为探明影响梨每花序花朵数量的因素,调查了230个梨品种每花序花朵数量,简析了每花序平均花朵数量的梨品种数量频度分布。并从中选取每花序花朵数量极端差异的2个品种‘黄金’梨和‘金星’梨,采用液相串联质谱法(LC-MS)测定其花芽ZT、IAA、ABA含量,分析其每花芽分化花朵数量与植物激素的关系。结果表明:在常见梨品种中每花序有5~9朵花,‘黄金’梨的最多,平均为11.5朵,‘金星’梨的最少,平均为3.6朵。在花芽分化中后期,‘黄金’梨花芽的ZT含量极显著高于‘金星’梨;花芽分化过程中,‘金星’梨花芽IAA含量始终极显著高于‘黄金’梨;2个梨品种花芽ABA含量差异不显著。综上,花芽分化中后期花芽内高含量的细胞分裂素有利于促迚花朵的分化。     

Flowering influences adventitious root formation in chrysanthemum cuttings

Root formation in chrysanthemum (Dendranthemum grandiflora (Ramat.) Kitamura) cuttings was reduced as flowers developed on stock plants. This effect was shown for all ten cultivars evaluated in this study. Not all cultivars were affected equally by the presence of flower buds on cuttings. There was no relationship (r² = 0.06) between root formation in vegetative cuttings and the ability for a cultivar to root from flowering cuttings. IBA (1 mM) could partially overcome the negative effect of flowering on root formation, but cuttings taken after the flower buds had fully opened failed to root even after auxin treatment. Removing buds from cuttings or continually removing flower buds during stock plant growth reduced rooting compared to cuttings with flower buds intact. Furthermore, cuttings taken from the top three nodes of the stock plant containing flower buds rooted comparably to cuttings taken from the lower stem section that contained only vegetative buds. The negative influence of flowering on root formation appears to be due to the photoperiodic induction of the flowering stimulus rather than a direct competition for resources between flowers and developing roots.     

Identification of Petunia hybrida cultivars that diurnally emit floral fragrances

In order to identify genetic resources for breeding fragrant petunias for use as bedding plants, volatile compounds released by day from the flowers of 40 commercial Petunia hybrida cultivars were analyzed using a solid-phase micro-extraction technique coupled with GC–MS. The three cultivars with solid deep-blue flowers that accumulate malvidin in corollas with high tissue pH were found to emit abundant iso-eugenol as the principal floral fragrance. Several other cultivars that emitted considerable amounts of methylbenzoate and/or benzylbenzoate from the flower were also identified. Association between the floral fragrance and the other floral traits such as floral anthocyanin composition and corolla-tissue pH was discussed.     

香石竹无土栽培研究

以岩棉为介质栽培香石竹,用三种不同灌水量、二种不同定植方式,检验其对六个香石竹切花品种的生长和产量的影响。结果表明,岩棉栽培的香石竹比土壤栽培的生长发育早、开花早、花期高峰提前、切花产量高;不同定植方法与生长发育的相关不显著;不同品种对灌水量需要不同,品种24、31和46号需水量少,45号需水量高,43和48号居中,灌水量少,有利于香石竹的生殖生长,有提早开花的趋势。不同品种在无土栽培条件下,以31号产量最高,其次为43、48、24、45和46号,而土培以43号为高,其次为46、24、48、31和45号。     

Ethylene Production During Senescence of Flowers

A method of determining ethylene production by detached flowers is described. A surge of ethylene has been shown to accompany the wilting of carnation flowers at the end of senescence. This surge is independent of fungal infection and it is concluded that in the infected flower the major source of ethylene production is the host tissues.

A similar surge of ethylene production has been observed when the inflorescence wilts on the plant between 20 and 40 days from flower opening.

At temperatures above 7·2° C. (45° F.) the ethylene surge was accompanied by collapse of the petals and rapid loss of water. Cut flowers kept continuously below 7·2° C. slowly declined in weight, the petals became flaccid and ethylene production was negligible. Infection of the flowers with fungus did not materially alter the effect of temperature on the ethylene production.     

基于花色表型的牡丹和芍药品种数量分类研究

以38个牡丹和14个芍药为试材,采用色差仪对芍药属品种进行花色表型测定,研究芍药属品种数量分类的情况,以期为芍药属品种鉴定、分类及花色育种提供参考依据。结果表明:聚类分析得到的结果不能科学表征牡丹和芍药花色的分类特点;ISCC-NBS色彩名称表示法对花色的定义更为精确,可将牡丹花色分为黄色、白色、绿色、浅粉色、粉紫色、粉红色、红色、红紫色和红黑色系9类色系;芍药花色分为白色、浅粉色、粉红色、红色和红黑色系5类色系。同时发现芍药属品种花色丰富,且不同色系的芍药属品种花色差异较为显著。     

‘四季桂’不同季节的花芽分化与发育比较

利用显微解剖和石蜡切片技术,对四季桂品种群中‘四季桂’(Osmanthus fragrans‘Sijigui’)不同季节的花芽分化及开花特性进行研究。‘四季桂’一年成花3次,分别于3月初、6月上旬和10月底开始花芽分化,4月下旬、8月底和11月底完成,分别历时约2个月、2个半月和1个月。6月开始的花芽分化和开花过程与秋桂品种群基本相似,分化后需要低温才能开花,最终形成聚伞花序,无总梗,花粉发育正常。而10月底分化的花芽在完成分化后随即开花,形成的花序有总梗,且有伸长与未伸长之分,长度分别为(0.80±0.11)cm和(3.50±0.71)cm。3月分化的花芽与新梢同时生长发育,分化完成后随即开花。春季和冬季的两次分化形成的均是圆锥状花序,具总梗,花粉均败育。结果表明‘四季桂’自身存在着不同的成花机制。     

不同杏品种抗寒性及生理指标

以"晋梅杏""凯特""鸡蛋杏""金太阳"一年生休眠枝条和带花枝条为试材,通过不同低温处理,测定膜透性、保护酶活性和渗透调节物质,比较生理指标在低温下的变化以及与抗寒性的关系,分析各指标间的相关性,以期为筛选抗寒新品种提供参考依据。结果表明:随温度降低,枝条相对电导率、枝条丙二醛(MDA)含量、枝条脯氨酸含量、杏花MDA含量、杏花脯氨酸含量呈上升的趋势;枝条超氧化物歧化酶(SOD)活性、花朵SOD活性整体呈先升后降的趋势。"凯特"枝条中MDA含量与其它3个品种差异显著;"金太阳"枝条中脯氨酸含量与其它3个品种差异显著。花朵中MDA含量与4个杏品种的抗寒性呈负相关;除"鸡蛋杏"以外,枝条中脯氨酸含量与抗寒性呈正相关。相对电导率和枝条中SOD活性、枝条中脯氨酸含量、花朵中MDA含量呈极显著正相关,与花朵中脯氨酸含量呈显著负相关。花朵中MDA含量与花朵中SOD活性、花朵中脯氨酸含量呈极显著负相关;花朵中SOD活性与花朵中脯氨酸含量呈极显著正相关。综上所述,4种杏品种抗寒性强弱顺序为"金太阳">"晋梅杏">"鸡蛋杏">"凯特"。