沙芥花粉萌发特性和柱头可授性的研究

 用培养基发芽法研究沙芥花粉萌发特性;用人工异株授粉法和联苯胺—过氧化氢法测定柱头可授期。结果表明：沙芥花粉萌发的最佳培养基是20%蔗糖+0.001%硼酸;花粉能够萌发的温度范围为15～38 ℃,最适萌发温度为25 ℃;从花蕾充分膨大期至开花后16 h花粉活力较强,开花后48 h花粉基本无活力;花粉储藏的适宜条件为低温（4 ℃）,储藏期为7 d。柱头可授期为开花前48 h至开花后96 h,其中开花后24～72 h可授性强。     

Low temperature storage and in vitro germination of cherimoya (Annona cherimola Mill.) pollen

Due to the protogynous dichogamy of cherimoya and to the absence of proper pollinating vectors, hand-pollination with fresh pollen is a common practice for cherimoya commercial production. In order to optimize the process of hand-pollination, in this work we have studied the conservation of cherimoya pollen at −20, −80 and −196 °C for up to 3 months. In vitro pollen germination of fresh pollen was 57.1% and it was progressively reduced with conservation time at the three temperatures studied reaching a minimum after 3 months of storage of 10.4%, 14.2% and 13.6% at −20, −80 and −196 °C, respectively. Differences in germination among temperatures were only significant during the first 2 weeks of storage. Field pollinations with pollen stored for up to 3 months at the three temperatures show no yield differences compared to pollinations performed with fresh pollen. The results indicate that pollen collected and stored at sub-zero temperatures at the beginning of the cherimoya blooming season can be used along the whole blooming season avoiding the need of collecting fresh pollen daily.     

Effects of auxins on soluble carbohydrates,starch and soluble protein content in Aechmea blanchetiana (Bromeliaceae) cultured in vitro

We investigated the content of soluble carbohydrates, starch and soluble proteins after treatment with auxins indole-3-butylic acid (IBA) and 1-naphthaleneacetic acid (NAA) during the development of Aechmea blanchetiana (Bromeliaceae) plantlets cultured in vitro, to determine the contribution of these compounds in plant propagation. Fresh and dry mass of roots increased more than fivefold with NAA (5.37 and 16.11 μM) compared to those with the auxin-free control. After 70 days of culture concentration of soluble protein concentration content was higher in the roots and leaves of plantlets treated with IBA and similar to auxin-free control, while a maximum accumulation of sugars was observed at 90 days in the roots of plantlets treated with NAA (0.54 μM) or IBA (0.49 and 4.9 μM). The major carbon reserves in the roots were soluble carbohydrates, suggesting that they play an important role in the growth of in vitro-cultured epiphytic bromeliads.     

Seasonal variations in nutritional components of green asparagus using the mother fern cultivation

Harvesting season for green asparagus can be extended by the use of the mother fern method and greenhouse cultivation. To evaluate seasonal variations in nutritional quality of green asparagus, the compositional profiles of fresh spears (Asparagus officialis L. cv. UC157 F1) harvested each month from March to October were compared in two locations of China using mother fern method. During the harvest season, dry matter content, soluble sugar, crude fiber, rutin and total soluble phenol in spears exhibited marked variation. Although there was no significant difference in total amino acid contents among most of months throughout the season, but quantitative changes in some specific amino acids occurred. Fresh spears harvested in warm season (from June to July) contained lower level of soluble sugars, dry matter, ascorbic acid and higher nitrate, crude fiber, total phenolics and rutin contents compared with those in cooler months. Asparagus harvested in spring accumulated relatively higher level of soluble sugar, carotenoid and chlorophyll contents than those in autumn, but total phenol and rutin contents were higher in autumn than in spring. The relationships between weather data and nutritional quality parameters of asparagus spear during harvest season were also discussed.     

Defruiting effect of young Fuyu persimmon (Diospyros kaki) on assimilate partitioning in-season and early growth the next season

Changes in the distribution of dry matter and nonstructural carbohydrates in various parts of young ‘Fuyu’ persimmon (Diospyros kaki) were examined with 3- and 4-year-old trees with (fruited) and without fruits (defruited). The effect of such changes was then monitored with regard to the magnitude of new growth the following year. From June 15 to November 1, fruiting significantly decreased the rate of dry weight accumulation in perennial parts of the tree. Dry matter was partitioned the most to fruits (68–72%) and the least to the roots. Of the total dry weight, root accounted for 8–27% in fruited and 58–62% in defruited trees. During this period, soluble sugars were three times more in fruited than in defruited trees, but more than 95% of sugars were in the fruits. Starch content increased in defruited trees, more than 93% of which being distributed to the perennial parts. Compared with fruited trees, defruiting in the previous year increased new shoot growth and the number of fruits the following year, with a 20–58% greater increase in dry matter. During the new growth from April 10 to June 10 the following year, root dry weight decreased by 30–32% in defruited trees, whereas it increased by 20–80% in the fruited ones. Soluble sugars in roots decreased by 8.8–19.7 g in defruited trees but increased by 9.7–12.3 g in fruited ones. Starch in roots decreased by 68–75.1 g in defruited trees but increased by 10.2–13.3 g in fruited ones. However, there were no significant differences in soluble sugars and starch in the newly grown parts. It was estimated that a 1-g difference in dry matter accumulated in the previous season resulted in a 116-mg and 256-mg difference in dry weight of newly grown parts, and a 6.5-mm and 17.5-mm new shoot in the following season for 3- and 4-year-old trees, respectively.     

甜樱桃胚珠、花粉发育与温度变化的关系

为探明甜樱桃性细胞发育规律及其所需的温度条件,利用石腊切片方法观察了露地栽培条件下,甜樱桃胚珠、胚囊和花粉发生发育过程的形态变化特征及其所需最低和最高温度。结果表明,甜樱桃的胚珠、胚囊和花粉发育,是在春季伴随着温度逐渐升高完成的;花前21￣35d,随着气温的升高,小孢子母细胞由相互连接在一起逐渐分离呈游离状态,在开花前21d的萌芽期前后完成2次分裂,由一个细胞分裂成四个细胞(四分体)形成花粉粒,此过程是在较低的温度(-0.1￣12.8℃)条件下完成;萌芽以后,胚珠的发育速度加快,开花前14d左右完成胚珠发育过程,胚囊的形成是在开花前7d内完成;甜樱桃的胚珠由单层珠被、珠心及胚囊构成。试验结果可为甜樱桃设施栽培的温度管理提供参考。     

蝴蝶兰催花及开花过程中可溶性糖含量变化的研究

根据蝴蝶兰的生长发育状态将蝴蝶兰催花及开花过程分为4个时期:抽梗前期,抽出花梗期,出现花苞期,开花期。对蝴蝶兰花梗诱导及开花过程中可溶性糖在植株各器官间的分布进行了研究。结果表明:在蝴蝶兰花梗诱导及开花过程中不同器官的可溶性糖含量有各自的变化规律。     

Fructose inhibits pear pollen germination on agar medium without loss of viability

Pollen of Japanese pear (Pyrus pyrifolia Nakai) germinated well on agar medium containing 10% sucrose or glucose, but not on agar containing fructose. The inhibitory effect of fructose was dose-dependent. Sucrose enhanced pollen tube growth much more effectively than glucose. Addition of 5% fructose to 5% or 10% sucrose or glucose media suppressed germination completely. Ungerminated pollen, however, showed similar respiration rate and stainability against acetocarmine dye as germinated pollen. When pollen was transferred onto fructose medium after culturing it on glucose or sucrose medium for 1–2 h, germination was completely impeded. Reversely, pollen transferred to sucrose or glucose medium from fructose medium germinated at almost the same ratio as pollen on sucrose or glucose medium without transfer. Thus, pollen inhibition by fructose is reversible. Compared with uncultured pollen, cultured pollen contained less than half amount of total sugars, even if failed in germination on fructose medium. Germinated pollen on sucrose and glucose media contained sucrose and glucose, but ungerminated pollen on fructose medium contained only trace levels of these sugars, suggests that pollen on fructose medium predominantly uses sucrose and glucose as respiration substrates and cannot maintain the constant levels of these sugars. However, as pollen germination occurred on agar medium without any sugar, fructose may impede a physiological factor that triggers germination, and once the trigger is impeded, many physiological pathways including sugar biosynthesis may be blocked.     

Seasonal Changes of Shoot Carbohydrates and Growth Characteristics of ‘Trakya İlkeren’ Grape Variety (<Emphasis Type="Italic">Vitis vinifera</Emphasis> L.)

This research was conducted to determine the changes in the seasonal carbohydrates of annual shoots and growth characteristics of 10 years old ‘Trakya ?lkeren’ grape variety. Grapevines are grafted on 5BB and 5C rootstocks and they were grown in heavy clay soil conditions. In the study, changes of sugar, starch and total carbohydrates were determined from bud burst to dormancy. While sugar, starch and total carbohydrates showed significant differences (P < 0.01) there were no differences between rootstocks. Although sugar, starch and total carbohydrates of shoots decreased from bud burst to blooming, they increased thereafter until vegetative growth stopped. Total carbohydrates of annual shoots have been found to accumulate in period from blooming to harvest. Total and mean leaf area, shoot length and diameter, total chlorophyll and chlorophyll a/b ratio showed significantly variation among rootstocks and phenological stages (P < 0.01). Whereas the highest chlorophyll contents were found in the blooming, it was found at the lowest through to harvest. Overall mean and total leaf area, shoot length and shoot diameter, total chlorophyll content and chlorophyll a/b ratio were significantly higher on 5BB grafted vines. In the study, 5BB rootstocks are found suitable in terms of shoot carbohydrate accumulation and growth characteristics for ‘Trakya ?lkeren’ grape variety.     

Effect of high temperatures in the pre-blooming and blooming periods on ovule formation,pollen grains and yield of ‘Granada’ peach

The aim of this work was to evaluate the effects of high temperatures in the pre-blooming and blooming periods on the growth of sexual gametes and yield of ‘Granada’ peach. The experiment was carried out in the commercial orchard of Charqueadas, under the subtropical conditions of the Central Depression at Rio Grande do Sul State, Brazil (28°57′S; 51°37′W; 30 m alt.). Two treatments were tested: (1) trees in the greenhouse with partial ventilation and (2) trees in the orchard. The phenology, morphologic constitutions of the pollen grains, ovule growth, yield and germination (%) of pollen grains and fruit set were evaluated. High temperatures in the pre-blooming and blooming periods anticipated the break of dormancy and blooming. These conditions also delayed the female gametophytes (embryo sac) and promoted anomalies in the formation of male gametophytes. Those factors promoted low pollen viability and a lack of synchrony in fertilization, thereby generating low fruit set percentages and yield.     

Plant carbohydrate partitioning of Lachenalia cv. Ronina during bulb production

Carbohydrate partitioning was investigated in different plant organs of Lachenalia cv. Ronina during bulb production under a low temperature regime. At 4-week intervals, data were collected on bulb, roots, leaves, inflorescence and carbohydrate composition. The roots and especially the bulb were found to be the main starch sinks of the plant, whilst the leaves and the inflorescence were the main source for soluble sugars. Changes in the starch concentration closely followed dry weight changes in the bulb during the growing season. When bulbs were initially exposed to a low temperature, starch was converted to soluble sugars, but thereafter sugars were low, indicating continued export and conversion to starch. Low sugar levels in the leaves and high levels in the inflorescence, with continuous starch increase in the bulb and roots, probably indicate that the inflorescence, but especially the leaves, produced ample photosynthates during the growing season.     

Carbohydrate changes in flowers,leaves, shoots and spurs of ‘Cox’s Orange Pippin’ apple during flowering and fruit setting periods

Summary

Changes of carbohydrate concentrations in different parts of the flower and the surrounding tissues (leaves, spurs and shoots) were measured in apple (Malus pumila) in 1987 and 1988, during the periods of flowering and fruit setting, to investigate their importance for fruit setting. HPLC was used for soluble sugar and sorbitol analysis. Starch was hydrolysed to glucose enzymatically and glucose concentration was determined colorometrically to estimate starch concentrations. Soluble sugars plus sorbitol (the soluble pool) increased rapidly in all parts of the flower from bud burst until full bloom. In contrast, in the same period, starch concentrations decreased rapidly and reached about zero at full bloom in the storage organs (shoots and spurs), indicating starch conversion to sugars and their movement to the growing flowers. Sorbitol was the most abundant carbohydrate in all apple tissue measured, with the exception of sepals, in which glucose concentration was the highest from full bloom onwards. Sepals had much higher glucose and fructose concentrations than leaf laminae but much lower sorbitol concentrations. Although dry weight, soluble pool and starch concentrations and total soluble pool content increased in the receptacle after petal fall, sucrose concentrations and total sucrose content dramatically decreased. These results suggest a preferential mobilization and utilization of sucrose rather than sorbitol during the fruit setting period and probably an important role of sucrose metabolism in fruit setting.     

Carbohydrate profiles in the graft union of young sweet cherry trees grown on dwarfing and vigorous rootstocks

In composite (scion–rootstock) dwarfing fruit trees, an overgrowth at the graft union is often observed, the severity of which is correlated with degree of dwarfing. The graft union of dwarfing sweet cherry (Prunus avium L.) rootstocks may limit soluble sugar transport or starch mobilization, leading to localized accumulation. Soluble sugars and starch were measured in the tissues surrounding the graft union of young ‘Rainier’ (2002) and ‘Lapins’ (2003) sweet cherry trees on ‘Gisela 5’ (‘Gi 5’; dwarfing) and ‘Colt’ (vigorous) rootstocks. Separate rootstock shank, rootstock, graft union, and scion tissues were analyzed for both starch and soluble sugar content throughout the growing season in both years. Starch concentrations did not vary among locations within the graft union for ‘Rainier’ on either the dwarfing or vigorous rootstock, or for ‘Lapins’ on the dwarfing stock. However, for ‘Lapins’ on ‘Colt’, starch was highest in the rootstock shank and declined vertically (rootstock shank ? rootstock > union > scion). Soluble sugar concentrations were generally similar to or higher in scions on ‘Gi 5’ than on ‘Colt’, and were similar to or lower in the rootstock and rootstock shank on ‘Gi 5’ than on ‘Colt’. Results suggest that rootstock has a significant effect of localized accumulations of carbohydrates above and within the graft union of ‘Gi 5’ and below the graft union of ‘Colt’.     

Pollen grains of heat tolerant tomato cultivars retain higher carbohydrate concentration under heat stress conditions

Exposure to high temperatures (heat stress) causes reduced yield in tomatoes (Lycopersicon esculentum), mainly by affecting male gametophyte development. Two experiments were conducted where several tomato cultivars were grown under heat stress, in growth chambers (day/night temperatures of 31/25 °C) or in greenhouses (day/night temperatures of 32/26 °C), or under control (day/night temperatures of 28/22 °C) conditions. In heat-sensitive cultivars, heat stress caused a reduction in the number of pollen grains, impaired their viability and germinability, caused reduced fruit set and markedly reduced the numbers of seeds per fruit. In the heat-tolerant cultivars, however, the number and quality of pollen grains, the number of fruits and the number of seeds per fruit were less affected by high temperatures. In all the heat-sensitive cultivars, the heat-stress conditions caused a marked reduction in starch concentration in the developing pollen grains at 3 days before anthesis, and a parallel decrease in the total soluble sugar concentration in the mature pollen, whereas in the four heat-tolerant cultivars tested, starch accumulation at 3 days before anthesis and soluble sugar concentration at anthesis were not affected by heat stress. These results indicate that the carbohydrate content of developing and mature tomato pollen grains may be an important factor in determining pollen quality, and suggest that heat-tolerant cultivars have a mechanism for maintaining the appropriate carbohydrate content under heat stress.     

广东荔枝主要品种花粉生活力研究初报

对广东荔枝主要品种花粉的萌发率、贮藏性进行试验,‘糯米糍’最强,全花期萌发率最高年份达82.71％,依次是‘桂味’74.87％,‘怀枝’56.44％,‘三月红’54.74％,‘黑叶’44.78％,‘妃子笑’几乎没有生活力.一般盛花期比初、末花期强.7℃不萌发,15℃低,23℃或24～28℃最适.干燥器贮藏比自然贮藏大大延长花粉寿命,10天的萌发率‘桂味’58.93％,‘糯米糍’41.84％,‘怀枝’50.69％,均较‘黑叶’、‘三月红’耐藏;低温加干燥可延长贮藏.短时浸泡对萌发率影响不大,浸泡一天显著下降,浸泡两天几乎无萌发力.花蜜原液严重抑制萌发.     

Dry weight and carbohydrate distribution in different tree parts as affected by various fruit-loads of young persimmon and their effect on new growth in the next season

This study was conducted to determine the changes in the accumulation of dry weight (DW) and the distribution of carbohydrates in different parts of young persimmon (Diospyros kaki) as affected by various fruit-loads. The effects of such changes were monitored with regard to the abundance of new growth in the following year. On June 15, the fruit-load was adjusted to a leaf–fruit (L/F) ratio of 10, 20, and 30, and some trees were completely defruited. Between June 15 and November 11, the increase in DW was less in the defruited and more in the higher L/F-ratio trees. Among the various tree parts, the DW increased the most in the fruits during the same period. It was observed that the lower the L/F ratio, the more the DW in the fruits: the fruits accounted for 78.7% of the total DW in the 10-L/F, 57.6% in the 20-L/F, and 49.7% in the 30-L/F ratio trees. In contrast, as the L/F ratio increased, the DW distribution to the roots increased to 3% in the 10-L/F, 13% in the 20-L/F, and 26% in the 30-L/F ratio trees and 61% in the defruited trees. During this period, carbohydrates were distributed mostly to the fruits, but as the L/F ratio decreased, their distribution to permanent tree parts decreased. The distribution of soluble sugars and starch to the permanent parts was 1% and 14% in the 10-L/F, 3% and 48% in the 20-L/F, 9% and 57% in the 30-L/F ratio trees, and 71% and 93% in the defruited trees, respectively. Maintaining a lower L/F ratio resulted in a decrease in the shoot and fruit numbers in the following year: there were zero and four fruits in those trees with an L/F ratio of 10 and 20, respectively. The carbohydrates decreased in the roots of both the 30-L/F ratio trees and the defruited trees, whereas the defruited trees showed more new shoot growth in the following year. In the roots of the trees with the L/F ratio of 30, soluble sugars and starch decreased by 7.6 g and 1.8 g, respectively, during the spring growth, whereas, in the roots of the defruited trees soluble sugars and starch decreased by 33.3 g and 94.6 g, respectively.     

Do the threats of alder and birch allergenic pollen differ within an urban area?

Currently, the increasing frequency of inhalant allergy is often linked to the urbanization effect. The pollen forecasts for a given city are most often prepared using data from one aerobiological station. However, there is evidence that the pollen concentrations in the air might differ depending on the city area and the height of the pollen trap. This study evaluated the spatial differences in the daily concentrations of alder and birch pollen grains in an urban area in relation to the proximity of the pollen sources and meteorological parameters. Pollen grains were sampled in Rzeszów in 2014–2016 by three volumetric traps located at the roof and nose levels in two city areas that differed in the numbers of alder and birch trees. The daily pollen concentrations were categorized into three allergy symptom thresholds. The relationship between the daily pollen concentrations and meteorological variables was examined using a redundancy analysis and circular statistics. There were spatial differences in the pollen season intensity and, to a lesser extent, the variability in its course. Generally, higher concentrations were registered at the roof level and in the city suburbs than at the nose level and in the downtown area where alder and birch trees were less numerous. Despite the spatial variability of the pollen concentrations and the differences in the proximity and abundance of pollen sources, the risks for allergy sufferers were similar throughout the city. It was concluded that the main cause of this phenomenon is the high dispersal abilities of Alnus and Betula pollen grains. Although temperature seems to be a crucial factor that influences the airborne pollen of both taxa, several weather variables were found to have complex impacts on the daily concentrations.     

GA_3、2,4-D、B和蔗糖对梨花粉生活力及花粉生长速度的影响(英文)

以5个亚洲梨品种为试材,通过离体培养研究了花穗中花的着生部位,不同浓度的GA3、2,4-D和蔗糖对花粉生活力、花粉管生长速度的影响。结果表明,不同品种的花粉生活力差异明显,黄花花粉萌发快;新世纪花粉生活力强,花粉管生长迅速。花的着生位置及花器官的发育程度对花粉生活力有明显影响,边花的生活力比中心花强。不同浓度的B、2,4-D、GA3对花粉萌发及花粉管生长均有不同程度的影响,高浓度的GA3、2,4-D抑制花粉管的生长,但浓度较高的蔗糖能促进花粉粒的萌发和生长,且两者呈正相关(R2=0.983)。     

珍稀濒危植物掌叶木的开花生物学特性与繁育系统

通过野外观察、杂交指数估算、授粉特性分析及人工控制授粉试验等方法对珍稀濒危植物掌叶木（Handeliodendron bodinieri）开花生物学特性和繁育系统进行研究。结果表明：（1）掌叶木每年开花1次,花期在4月下旬到5月中下旬,开花的起止时间及花期的长短受当地气候影响较大;（2）花多为假两性花,即形态上为雌、雄蕊完整的两性花,而功能上为雌、雄蕊选择性败育形成的单性花,偶见雌、雄蕊可育的真两性花植株;单性花通常雌、雄异株,且雌株较雄株少,花序较雄株短5.6 cm,花期也较雄株短2周左右,雄株花序上偶尔见雌花单花;（3）单花经历萌动、露白、展开、盛开、凋落5个阶段,历时5 ~ 6 d;雄花从萌动到开花1 d的花粉活力高达90.5%,开花2 d后活力显著下降;雌花柱头在展开前部分具可授性,展开后1 ~ 3 d均具可授性,花粉活力与柱头可授性重叠;（4）雄花单花花粉量为51 461个,雌花单花胚珠数6,花粉胚珠比（P/O）为8 577,杂交指数为4,结合人工授粉、套袋、套网和自然授粉坐果率判断,掌叶木繁育系统为专性异交,传粉过程需要传粉者,可能存在无融合生殖。（5）掌叶木花性别分化复杂,可孕花数量较不孕花少,可育雌、雄蕊存在较大的空间隔离,加之不稳定的传粉环境,可能是其濒危的重要生殖生物学原因。     

根域限制对‘巨玫瑰’葡萄果实可溶性糖含量及相关代谢酶活性的影响

 以‘巨玫瑰’葡萄（Vitis vinifera L. × V. labrusca L.）为试材,从始熟期开始研究了根域限制栽培对果实可溶性糖积累及相关代谢酶活性的影响。结果表明：‘巨玫瑰’葡萄果实中主要以葡萄糖和果糖积累为主。从始熟期开始果实中的葡萄糖和果糖含量持续增加,与此同时,酸性转化酶（AI）的活性也随果实发育进程而逐步增强。AI活性与果实中含量最多的葡萄糖和果糖含量显著相关。中性转化酶（NI）和蔗糖合成酶（SS）的分解方向的活性只是在始熟期3周后开始增加,且活性低于AI。蔗糖合成酶（SS）的合成方向和蔗糖磷酸合成酶（SPS）的活性在始熟期开始后稍有增加,此后保持平稳,且活性远远低于蔗糖分解相关酶AI、NI和SS的分解方向活性。根域限制栽培可以显著提高‘巨玫瑰’果实中可溶性糖的含量、糖积累期间的AI活性和成熟时的NI活性,但对其他酶活性影响不显著。由此推断AI是葡萄果实糖积累的最重要的调节因子,也是根域限制提高果实糖含量的关键代谢酶。