Dioecy inHonkenya peploides var.major (Caryophyllaceae)

Sexual difference and pollination system inHonkenya peploides var.major were investigated. The present analyses indicate that sex expression of this plant is functionally dioecious, rather than androdioecious, as described previously. Its flowers are largely pollinated by small bees, hover-flies, flies, and ants. Female flowers were morphologically characterized by conspicuously longer styles and smaller petals, and had no pollen grains, while male flowers had shorter styles, larger petals, and longer filaments, and produced viable pollen grains. Although the male flowers possess many ovules in an ovary, they set fruits at a very low frequency in natural conditions and did not produce fruits by pollination experiments. We suggest that the dioecy of this species has been derived from hermaphrodite through gynodioecy, and not directly from hermaphrodite.     

A supplementary contribution of ants in the pollination of an orchid, Epipactis thunbergii, usually pollinated by hover flies

It has been controversial how extensively ants contribute to pollination, and we evaluated the contribution of the Japanese carpenter ant, Camponotus japonicus, to the pollination of an orchid, Epipactis thunbergii. Two-year field studies revealed that (1) the ant workers foraged even in cool/cloudy conditions and accordingly visited orchid flowers more frequently (about 40% of all the visitors) than hover flies, the principle pollinators (10–20%), and that (2) the flower-visiting ants occasionally removed pollinia from the anther and then delivered pollen onto the stigmatic surface of other flowers, although self-pollination might frequently occur in the consecutive visits of flowers within an inflorescence. An artificial pollination experiment with pollinia which had been transferred to the ant integument showed that (3) the treated flowers produced as many fruits and seeds as control flowers. We concluded that C. japonicus workers could actually pollinate E. thunbergii flowers and their relative importance as pollinators appeared to be largely dependent on the abundance of flower-visiting workers or weather conditions during the flowering period, which mainly determined the availability of hover flies.     

Significance of flower exploding pollination on the reproduction of the Scotch broom, <Emphasis Type="Italic">Cytisus scoparius</Emphasis> (Leguminosae)

The significance of single flower visits by pollinators on the reproductive success of the Scotch broom, Cytisus scoparius, with explosive flowers was investigated. Unexploded flowers (intact flowers) produced no fruit, implying that autonomous selfing and apomixis do not occur and that the explosion of flowers by insects is necessary for the fertilization of flowers. The fruit set in the natural condition was intermediate between that in artificial selfing or exploding and that in artificial outcrossing. Seed set and the ratio of seeds to ovules did not differ significantly between the natural condition and artificial outcrossing. The fruit set by a single flower visit from Apis mellifera was similar to natural conditions. Apis mellifera was the most frequent visitor and the number of flowers tripped open per hour was the highest among all the flower visitors. Approximately 75% of pollen on a flower disappeared in a single flower visit by A.mellifera. The small amount of pollen remaining on already-exploded flowers appears to be the reason why A.mellifera do not frequently visit already-exploded flowers. The higher seed set by outcrossing was believed to contribute to the seed set in both natural conditions and single flower visits by A.mellifera, and did not differ between them. Therefore, at least in Japan, A.mellifera appears to be the most important pollinator for C.scoparius, resulting in a high outcrossing rate with each single flower visit.     

Notes on the floral morphology in Vivianiaceae (Geraniales)

The functional floral morphology of the three genera of Vivianiaceae (= Ledocarpaceae, Geraniales), Rhynchotheca, Viviania and Balbisia, is compared. Likely pollination mechanisms are inferred from morphology and field observations. The flowers of Viviania are nectariferous and apparently zoophilous with nectar as the (primary) pollinator reward. Balbisia has pollen flowers without nectaries, its showy corolla indicates that it is also zoophilous with pollen as sole pollinator reward; bees were observed as flower visitors. One taxon (B. gracilis) may be anemophilous. Rhynchotheca has flowers without petals, with large, pendulous anthers and lacks nectaries. It shows synchronous mass flowering in its natural populations and is evidently anemophilous. A comparison with other Geraniales shows that nectar flowers with small anthers are likely the ancestral condition in Vivianiaceae. This suggests that the pollen flowers with larger anthers of Balbisia and Rhynchotheca may represent an apomorphic condition. The documentation of pollen flowers and anemophily in Vivianiaceae expands the range of known floral and pollination syndromes in Geraniales.     

Microgametophytes in flowers with and without fruits ofPhlox drummondii (Polemoniaceae)

Relationships between microgametophyte numbers per flower and fruit-set were sought inPhlox drummondii Hook. This was accomplished by counting fluorescentstained pollen tubes in flowers with and without fruits in 21 populations, and in flowers subject to either supplemental or sparse pollination, and then determining whether the flowers initiate fruits. There was a conspicuous variation in mean pollen tubes per flower (3–38) and in percent fruit-set (17%–92%) among populations. Neighboring populations often differed strikingly in these respects. Flowers with fruits had an average of 15.2 pollen tubes per stigma whereas those without had an average of 3 7 tubes. Over all flowers, there was a mean of 3.7 tubes per ovule. There was a strong correlation between mean tube number within populations and their percent fruit-set (r = 0.86). Supplemental pollination significantly enhanced fruit-set, thereby supporting the notion that fruit-set was pollen-limited in most populations. In both natural and artificial pollinations a portion of flowers without fruits still had several pollen tubes. The occurrence of fruitless flowers containing tubes is explained by attrition factors, like late-acting pollen-pistil incompatibility, and resource limitation. Fruit-set could be initiated with one pollen tube, but this rarely occurred in nature. Higher pollen loads were accompanied by higher percents of fruit-set and number of seeds per flower.     

Evaluation of formulations of Bacillus licheniformis for the biological control of tomato gray mold caused by Botrytis cinerea

Bacillus licheniformis N1, which has previously exhibited potential as a biological control agent, was investigated to develop a biofungicide to control the gray mold of tomato caused by Botrytis cinerea. Various formulations of B. licheniformis N1 were developed using fermentation cultures of the bacteria in Biji medium, and their ability to control gray mold on tomato plants was evaluated. The results of pot experiments led to the selection of the wettable powder formulation N1E, based on corn starch and olive oil, for evaluation of the disease control activity of this bacterium after both artificial infection of the pathogen and natural disease occurrence under production conditions. In plastic-house artificial infection experiments, a 100-fold diluted N1E treatment was found to be the optimum biofungicide spray formulation. This treatment resulted in the significant reduction of symptom development when N1E was applied before Bo. cinerea infection, but not after the infection. Both artificial infection experiments in a plastic house and natural infection experiments under production conditions revealed that the N1E significantly reduced disease severity on tomato plants and flowers. The disease control value of N1E on tomato plants was 90.5% under production conditions, as compared to the 77% conferred by a chemical fungicide, the mixture of carbendazim and diethofencarb (1:1). The prevention of flower infection by N1E resulted in increased numbers of tomato fruits on each plant. N1E treatment also had growth promotion activity, which showed the increased number of tomato fruits compared to fungicide treatment and non-treated control and the increased fruit size compared the non-treated control under production conditions. This study suggests that the corn starch-based formulation of B. licheniformis developed using liquid fermentation will be an effective tool in the biological control of tomato gray mold.     

Biological control by Clonostachys rosea as a key component in the integrated management of strawberry gray mold

Gray mold, caused by Botrytis cinerea, is an important strawberry disease. As gray mold control is difficult, there is a need to evaluate integrated methods to successfully manage the disease. The efficiency of integrating Clonostachys rosea sprays, fungicide sprays, and crop debris removal to manage gray mold was evaluated in field experiments conducted in 2006 and 2007. Leaf colonization by C. rosea (LAC), average number of B. cinerea conidiophores (ANC), gray mold incidence in both flowers (Iflower) and fruits (Ifruit), and yield were evaluated weekly. In both years, LAC was higher in the treatments with no fungicide. When compared to the check, ANC, Iflower and Ifruit were most reduced in treatments that included C. rosea sprays. Maximal reductions were achieved with the combination of C. rosea sprays, fungicide sprays and debris removal (96.62%, 86.54% and 65.33% reductions of ANC, Iflower and Ifruit, respectively). Otherwise, maximal yield (103.14% increase as compared to the check) was achieved with the combination of the three treatments. With just C. rosea sprays, ANC, Iflower and Ifruit were reduced by 92.01%, 68.48% and 65.33%, respectively, whereas yield was increased by 75.15%. Considering the individual effects, application of C. rosea was the most efficient treatment. Chemical control was effective only in plots without debris removal. Elimination of crop debris was the least effective method in reducing gray mold incidence in both flowers and fruits. The integrated control approach enhanced the efficacy of the individual methods of gray mold control and provided high strawberry yield. An important component of this integrated approach it the biological control with C. rosea.     

中国苋科苋属新记录种——鲍氏苋和布氏苋

我国有记录的苋属植物20余种,主要为外来杂草。苋属植物形态相近,常被误鉴。作者从送检的误鉴的标本中发现2个新外来种,根据拉丁文名种加词释义,分别命名为鲍氏苋(Amaranthus powellii S. Watson)和布氏苋(A. bouchonii Thell.)。鲍氏苋和布氏苋形态相近,分别产自美国西南部和欧洲,雌雄同株,具3～5雌花花被片,花被片不等长,等于或短于胞果,胞果开裂或不开裂。鲍氏苋和布氏苋可通过花被片数目和形态、胞果是否开裂、苞片大小相区分。该文还提供了鲍氏苋和布氏苋的中文形态描述及彩色图片,并对其分布、生境和危害状况进行了报道。     

Morphological alterations by ectopic expression of the rice OsMADS4 gene in tobacco plants

OsMADS4, a rice MADS-box gene, is a member of the GLO/PI family that specifies the identity of petals and stamens in combination with other MADS-box genes. We report here the ectopic expression of OsMADS4 fused to the CaMV 35S promoter in tobacco plants. Transgenic plants carrying the CaMV 35S promoter::OsMADS4 construct generated mutant flowers with a mosaic carpel, in which the tissue around the nectary was elongated and the styles reduced. The fruits were distorted, but viable seeds did develop. These phenotypes mimicked those of transgenic tobacco plants that ectopically express Antirrhinum GLO. However, unlike GLO, OsMADS4 did not cause any homeotic change in the first whorl of the transgenic flowers. These results suggest that the functional role of OsMADS4 in the outer whorls has diverged from that of its dicot counterparts.     

The fate of flowers and fruits of Cornus sanguinea L. in three contrasting Mediterranean habitats

Summary In the Mediterranean region of southern France, the fate of flowers and fruits of Cornus sanguinea, a deciduous shrub, was studied in three contrasting habitats: (1) an abandoned olive grove, (2) the edge and (3) the interior of a deciduous forest. Abundance of flowering and fruiting of C. sanguinea differed widely between the three habitats. The fate of the flowers, on the other hand, did not differ significantly between habitats. Taking all three habitats together, 77% of the flowers aborted, 23% initiated fruits, 6% developed mature fruits, and 3% produced ripe fruits that were eaten by birds. Likewise, there were for the most part no significant differences in the fate of immature and mature fruits between the habitats. On average, 58% of the immature fruits were abscised undamaged, 24% matured, 10% were damaged by insects and 8% dried up. Of the mature fruits, on average, 51% were eaten by birds, 23% damaged by insects, 20% dried up and 6% fell to the ground undamaged. Independent of habitat conditions, C. sanguinea seems to regulate the quantity of its seed crop primarily by limiting the number of flowers and secondarily by aborting surplus immature fruits, and the number of flowers is mainly controled by resource availability and genetic factors. In the case of C. sanguinea, both the fruit/flower ratio and the proportion of flowers producing mature fruits that are eaten by birds remain constant over a wide range of environmental conditions.     

Utilization on extrafloral nectaries and fruit domatia of Canavalia lineata and C. cathartica (Leguminosae) by ants

Utilization of the extrafloral nectaries (EFNs) and fruits of Canavalia lineata and C. cathartica by ants was investigated at 30 sites in Japan. The fruits of C. lineata and C. cathartica were inhabited by five and eight ant species, respectively. Ant nesting periods and their utilization of EFNs differed between C. lineata and C. cathartica. Canavalia lineata flowers once a year, and periods of EFN-utilization and fruit-nesting by ants do not overlap. The fruit-nesting ants on C. lineata seem to invade the plant from the holes made by moth larvae or breaches made by decay. The ants nesting on the fruits of C. lineata may defend the plant against seed herbivores because they feed on moth larvae. Canavalia cathartica flowers several times over a year, and fruits are found throughout the year; therefore, periods of EFN-utilization and fruit-nesting by ants are overlapped. Canavalia cathartica offers year-round nesting sites and food for ants, and therefore may receive a higher defensive effect from ants than C. lineata. Handling editor: Graham Stone.     

Synchronized dichogamy and dioecy in neotropicalLauraceae

In hermaphrodite neotropicalLauraceae a highly evolved dichogamous system is present which represents a kind of temporal dioecy. This system involves the existence of two flower morphs which are characterized by reciprocal phases of receptivity of the stigmas and pollen release. In some genera (Persea, Cinnamomum), nectar is produced as a reward for the flower visitors, while in other genera (Aniba, Clinostemon, Licaria), nectar is absent and pollen seems to be the only reward. This implies that in this case the flowers in the female stage must be deceptive flowers. In dioecious species of the generaOcotea andNectandra, both the male and female flowers attract the visitors with nectar. The pollen-ovule ratio of theLauraceae is comparatively low. — The type of reproductive system that characterizes theLauraceae, comprising functional dioecy, small, inconspicuously coloured flowers, pollination by small bees, and large, one-seeded fruits dispersed by birds, is quite prominent among trees of various families in the tropical lowland forest. The relationship between the different modes of flowering within theLauraceae and the causes for the correlation of their reproductive traits are discussed.     

山西口岸全国首次截获危险性蚧虫并蛎蚧

【目的】并蛎蚧属盾蚧科并蛎蚧属,该虫食性杂,危害植物种类多,极易随水果、苗木、景观花卉植物等寄主传播入境。并蛎蚧分布于美国、日本和我国台湾省,在我国大陆地区尚未见该虫的发生报道。2016年5月山西口岸从来自台北的水果释迦上截获了并蛎蚧,为我国大陆首次截获。【方法】通过显微形态特征的观察和测量进行种类鉴定,并研究并蛎蚧的生物学、生态学相关资料,对其进行风险评估。【结果】并蛎蚧与近似种的主要区别:中臀叶与第二臀叶愈合中间有腺刺,有第三对臀叶,中臀叶有向内延伸的硬化区。通过风险评估认为,来自我国台湾、日本的并蛎蚧入侵我国大陆的风险较大。并蛎蚧在大陆亚热带地区的定殖和扩散风险很大。【结论】我国大陆地区的气候条件、植物种类可为并蛎蚧的定殖提供可能的适生条件,各口岸应对进境的并蛎蚧寄主植物加强检验检疫。     

Breeding system of the annual Cruciferae, <Emphasis Type="Italic">Arabidopsis kamchatica</Emphasis> subsp. <Emphasis Type="Italic">kawasakiana</Emphasis>

The breeding system of an annual Cruciferae, Arabidopsis kamchatica subsp. kawasakiana, was studied in three natural populations. We applied four experimental treatments, open pollination, bagging, emasculation + bagging, and emasculation + hand-pollination + bagging. None of the emasculated flowers with bags produced fruits but we observed high fruit sets in the other three treatments. The results confirmed that A. kamchatica subsp. kawasakiana is a self-compatible, non-apomictic species that can produce seeds through auto-pollination. Considering the life cycle as an annual, increased reproductive assurance through auto-pollination should be critical for the maintenance of populations of A. kamchatica subsp. kawasakiana.     

日轮果属，越南唇形科黄芩亚科一新属

描述并绘制了越南唇形科一新属及新种：日轮果属(Heliacria Bo Li,C.L.Xiang,T.S.Hoang&Nuraliev)和日轮果(H. maritima Bo Li,C.L.Xiang,T.S.Hoang&Nuraliev)。日轮果属因具攀援藤本习性,花大且花冠为纯白色,花萼近辐射对称、5深裂、裂片长且在果期增大并开展,果实顶端具放射状的瘤状突起等特征而明显区别于黄芩亚科的其他5属。目前,该属仅发现于越南东南部沿海的平定省、富安省、庆和省和宁顺省,常生于海岸边干旱的低地矮林中。     

基于FTIR的三倍体罗汉果花粉直感效应研究

以四个品系的三倍体罗汉果雌株为材料,用五种不同的二倍体雄花分别对其授粉,利用傅里叶变换红外光谱法(FTIR)测定了其子代果实的红外光谱,并运用主成分分析和聚类分析研究了授粉雄花对子代果实化学成分的影响。结果表明:不同雄花授粉后,雌株F302、F323和F322各子代果实红外光谱中1 050 cm-1波数附近甜苷物质特征吸收峰的峰高有显著或极显著差异,雌株F311子代无籽果实的差异不显著;同时五种授粉雄花分别对雌株F302、F323、F322和F311子代果实在主成分二维投影图和聚类图中的排序也有明显的影响,但对不同品系雌株子代果实的排序影响不同,从而说明三倍体罗汉果的甜苷物质含量和整体成分含量均有较为明显的花粉直感效应,并且存在品种特异性。     

白背叶(大戟科)性系统和传粉生物学研究

为探讨野桐属(Mallotus)雌雄异株的进化和传粉机制,对白背叶(Mallotus apelta)野生居群的性系统和传粉生物学进行了研究。结果表明,所调查的白背叶居群均由雌性(F)、雄性(M)和少数两性(B)个体组成,平均性比为1：0.66：0.18(F：M：B);3种性别植株的基径大小差异不显著;雌株与两性植株的单花胚珠数、单果结籽数和自然结实率无显著差异;雄株与两性植株的花粉萌发率、花粉组织化学和花粉微形态特征也无显著差异,但雄株的单花花粉量是两性植株的1.26~1.63倍,且差异显著;雌株的异交结实率为96.67%,两性植株的异交结实率为76.00%,两者差异显著,说明居群内雌株的潜在种子生产力明显高于两性植株;野外观察到雄株和两性植株上的雄花具有访花者而雌株没有;雌株经套网处理后结实率超过30%而套袋处理不结实。这些表明白背叶具典型的亚雌雄异株性系统,雌株和雄株的适合度均高于两性植株;雌株以风媒传粉结实,两性植株可能兼有风媒和虫媒传粉特征。     

Factors affecting fruit set in Aizoaceae species of the Succulent Karoo

By reducing the number of flowers and fruits, intense grazing activities of domestic livestock are considered to have negative effects on the plant recruitment of perennial plants in the Succulent Karoo, South Africa. In the present study, the fruit set of six perennial species belonging to the Aizoaceae was investigated under two different grazing intensities. Two species (Cheiridopsis imitans and Leipoldtia schultzei) were examined more closely to determine whether factors other than grazing impact fruit production of these plants. Apart from reproductive output, the population structure of these two species was explored in heavily and slightly grazed areas.For all investigated species, heavy livestock grazing was identified as a major threat to fruit production. Deviations from this pattern were recorded in a drought year, when harsh weather conditions reduced herd sizes dramatically and the usually high grazing pressure was alleviated. However, detailed analyses revealed that also other biotic factors can cause severe fruit and flower losses even exceeding that caused by grazing. Caterpillars of the noctuid moth, Diaphone eumela, and two rodent species, Otomys unisulcatus and Rhabdomys pumilio, proved to be further important herbivores of flowers and fruits. Experiments with caged plants, excluding livestock from grazing, confirmed though that livestock grazing definitely accounts for a continuous reduction of fruit production. Insufficient pollination success was another parameter reducing fruit set; however, this was almost exclusively observed under low grazing pressure.     

Flower color affects tri-trophic-level biocontrol interactions

The adults of many parasitoid species require nectar for optimal fitness, but very little is known of flower recognition. Flight cage experiments showed that the adults of an egg parasitoid (Trichogramma carverae Oatman and Pinto) benefited from alyssum (Lobularia maritima L.) bearing white flowers to a greater extent than was the case for light pink, dark pink or purple flowered cultivars, despite all cultivars producing nectar. Survival and realised parasitism on all non-white flowers were no greater than when the parasitoids were caged on alyssum shoots from which flowers had been removed. The possibility that differences between alyssum cultivars were due to factors other than flower color, such as nectar quality, was excluded by dying white alyssum flowers by placing the roots of the plants in 5% food dye (blue or pink) solution. Survival of T. carverae was lower on dyed alyssum flowers than on undyed white flowers. Mixing the same dyes with honey in a third experiment conducted in the dark showed that the low level of feeding on dyed flowers was unlikely to be the result of olfactory or gustatory cues. Flower color appears, therefore, to be a critical factor in the choice of plants used to enhance biocontrol, and is likely also to be a factor in the role parasitoids play in structuring invertebrate communities.     

Carbon autonomy of reproductive shoots of Siberian alder (<Emphasis Type="Italic">Alnus hirsuta</Emphasis> var.<Emphasis Type="Italic"> sibirica</Emphasis>)

Carbon autonomy of current-year shoots in flowering, and of current-year shoots plus 1-year-old shoots (1-year-old shoot system) in fruiting of Siberian alder (Alnus hirsuta var. sibirica) was investigated using a stable isotope of carbon, ¹³C. The current-year shoot and 1-year-old shoot systems were fed ¹³CO₂ and the atom% excess of ¹³C in flowers and fruits was determined. The majority of photosynthate allocated to flower buds was originally assimilated in the leaves of the flowering current-year shoots. Of all the current-year shoots on fruiting 1-year-old shoots, only those nearest to the fruits allocated the assimilated photosynthate to fruit maturation. These results indicate that the current-year shoots and 1-year-old shoot systems are carbon-autonomous units for producing flowers and maturing fruits, respectively.