Prunus Serrulata Research Articles

Modeling dormancy break and bloom time for Japanese flowering cherry in warm climates

Modeling dormancy break and bloom time for Japanese flowering cherry in warm climates

都市内残存林における９年間のヤマザクラの着花状況と消長

This paper aims to make clear the growing and flowering condition of Prunus jamasakura under succession of broadleaved evergreen forest in an abandoned coppice woodlands, for conserving the seasonal landscape and bio-diversity in urbanized area. In 2008, we conducted the follow-up survey in“Kohnosu-Yama Forest Reserve”, and compared the data collected in 1999. The results are as follows: (1) Number of P. jamasakura decreased from 272 to 235 mainly ascribed to suppressing and shading of surroundings such broadleaved evergreen trees as Castanopsis sieboldii, Neolitsea sericea, Cinnamomum camphora and Machilus thunbergii. The height of died P. jamasakura was less than 14m (average was 9.6m) and the DBH was less than 20cm (average was 14.3cm). (2) The average tree height of existing P. jamasakura increased from 11.0m in 1999 to 11.7m in 2008, and the DBH also increased from 20.9cm in 1999 to 25.0cm in 2008. The most growing tree's height and DBH increased 6.5m and 13.7cm respectively. (3) Total flowering somewhat decreased in 2008 compared in 1999. (4) Removing the surrounding evergreen trees by volunteer activity was effective for encouraging P. jamasakura.

Effect of various drying methods on the germination of Prunus jamasakura seeds

Effect of various drying methods on the germination of Prunus jamasakura seeds

Change in flowering dates of Japanese Cherry Blossoms ( P. yedoensis Mats.) on campus of Wuhan University and its relationship with variability of winter temperature

Change in first-flowering dates and its correlation with climatic factors was mainly analyzed, and several predicting models for the first-flowering dates were established based on the flowering dates of Japanese Cherry Blossoms ( P. yedoensis Mats.) during 1947–2008 on campus of Wuhan University and the climatic data in the same period. The results show that: 1) in 1947–2000, the first-flowering dates advanced with 2.17 d per decade, with an overall trend of 11.72 d in the 54 years, the fading dates were postponed for only 1.83 d in the same period, and the florescence duration increased by 13.55 d; 2) the first-flowering dates have negative correlation with monthly average temperature from December to March. The increasing winter (from December to February) temperature is the main reason for the advancement of the first-flowering dates. Per 1°C increase in average temperature of February and wintertime makes the first-flowering dates advance by 1.66 d and 2.86 d, respectively; 3) some statistical models of the first-flowering dates were built up with average temperature of February and wintertime based on the data during 1947–2000, and they are detected independently during 2001–2008.

Using urban effect corrected temperature data and a tree phenology model to project geographical shift of cherry flowering date in South Korea

Temperate zone deciduous tree phenology may be vulnerable to projected temperature change, and associated geographical impact is of concern to ecologists. Although many phenology models have been introduced to evaluate climate change impact, there has been little attempt to show the spatial variation across a geographical region due to contamination by the urban heat island (UHI) effect as well as the insufficient spatial resolution of temperature data. We present a practical method for assessing climate change impact on tree phenology at spatial scales sufficient to accommodate the UHI effect. A thermal time-based two-step phenological model was adapted to simulate and project flowering dates of Japanese cherry (Prunus serrulata var. spontanea) in South Korea under the changing climates. The model consists of two sequential periods: the rest period described by chilling requirements and the forcing period described by heating requirements. Daily maximum and minimum temperature are used to calculate daily chill units until a pre-determined chilling requirement for rest release is met. After the projected rest release date, daily heat units (growing degree days) are accumulated until a pre-determined heating requirement for flowering is achieved. Model parameters were derived from the observed bud-burst and flowering dates of cherry tree at the Seoul station of the Korea Meteorological Administration (KMA), along with daily temperature data for 1923–1948. The model was validated using the observed data at 18 locations across South Korea during 1955–2004 with a root mean square error of 5.1 days. This model was used to project flowering dates of Japanese cherry in South Korea from 1941 to 2100. Gridded data sets of daily maximum and minimum temperature with a 270 m grid spacing were prepared for the climatological normal years 1941–1970 and 1971–2000 based on observations at 56 KMA stations and a geospatial interpolation scheme for correcting urban heat island effect as well as elevation effect. We obtained a 25 km-resolution, 2011–2100 temperature projection data set covering peninsular Korea under the auspices of the Inter-governmental Panel on Climate Change—Special Report on Emission Scenarios A2 from the Meteorological Research Institute of KMA. The data set was converted to 270 m gridded data for the climatological years 2011–2040, 2041–2070 and 2071–2100. The phenology model was run by the gridded daily maximum and minimum temperature data sets, each representing climatological normal years for 1941–1970, 1971–2000, 2011–2040, 2041–2070, and 2071–2100. According to the model calculation, the spatially averaged flowering date for the 1971–2000 normal is earlier than that for 1941–1970 by 5.2 days. Compared with the current normal (1971–2000), flowering of Japanese cherry is expected to be earlier by 9, 21, and 29 days in the future normal years 2011–2040, 2041–2070, and 2071–2100, respectively. Southern coastal areas might experience springs with incomplete or even no flowering caused by insufficient chilling required for breaking bud dormancy.

Measuring and modeling the variation in species-specific transpiration in temperate deciduous hardwoods

We investigated which parameters required by the MAESTRA model were most important in predicting leaf-area-based transpiration in 5-year-old trees of five deciduous hardwood species-yoshino cherry (Prunus x yedoensis Matsum.), red maple (Acer rubrum L. 'Autumn Flame'), trident maple (Acer buergeranum Miq.), Japanese flowering cherry (Prunus serrulata Lindl. 'Kwanzan') and London plane-tree (Platanus x acerifolia (Ait.) Willd.). Transpiration estimated from sap flow measured by the heat balance method in branches and trunks was compared with estimates predicted by the three-dimensional transpiration, photosynthesis and absorbed radiation model, MAESTRA. MAESTRA predicted species-specific transpiration from the interactions of leaf-level physiology and spatially explicit micro-scale weather patterns in a mixed deciduous hardwood plantation on a 15-min time step. The monthly differences between modeled mean daily transpiration estimates and measured mean daily sap flow ranged from a 35% underestimation for Acer buergeranum in June to a 25% overestimation for A. rubrum in July. The sensitivity of the modeled transpiration estimates was examined across a 30% error range for seven physiological input parameters. The minimum value of stomatal conductance as incident solar radiation tends to zero was determined to be eight times more influential than all other physiological model input parameters. This work quantified the major factors that influence modeled species-specific transpiration and confirmed the ability to scale leaf-level physiological attributes to whole-crown transpiration on a species-specific basis.

Aggregation of Lepidostomatidae in small mesh size litter-bags: implication to the leaf litter decomposition process

Invertebrate colonization during leaf litter decomposition was studied at the 2nd order of Yanase River, Iruma city, Saitama, Japan from November 13, 2002 to May 20, 2003. Two different mesh sizes (1 and 5 mm) of litter-bags were used to evaluate the decomposition of leaf litter of Sakura (Prunus lannesiana), bags were placed equally in riffle (water flow velocity: 0.2–0.6 m s−1) and pool (water flow velocity: 0.04–0.06 m s−1). Mass loss and invertebrates in the litter-bags were monitored at interval between 1 and 3 weeks, and the invertebrates were classified based on their functional feeding group. Among the invertebrates found inside the litter-bags, the case-bearing shredder Lepidostomatidae was the most dominant invertebrates and they were the early colonizer that appeared about 3 months after the litter-bags immersion. In absence or low number of leaf-shredders, the decomposition rates in 1 and 5 mm litter mesh bags followed the exponential (or first-order) decay kinetic (R 2: 0.72–0.92). However, the presence of a large number of leaf-shredders in 1 mm litter-bags caused an acceleration of decomposition process; that even resulted faster mass loss than the loss from the 5 mm mesh bags placed in riffle area (0.030 day−1 vs. 0.011 day−1). Our results shows the importance of using different mesh sizes of litter-bags in decomposition study, which is applicable to the experiment in lotic or lentic ecosystem. Using smaller mesh size of litter-bags can provide information on how significant the effect of detritus feeders on the decomposition process, while the bigger mesh size can represent better the natural decomposition process when a large number detritus feeders is present in the smaller mesh size of litter-bags.

여러 가지 조사료를 급여한 재래산양의 채식습성에 관한 연구

본 연구는 2007년 3월부터 10월까지 충남대학교 부속사육장 및 전북 남원시 운봉읍 소재 가축유전자원시험장에서 수행하였다. 공시시료는 화본과목초(gasses)는 Lolium perenne, Festuca arundinacea, Poa pratensis, Agrostis alba 및 mixed grasses의 5종과, 두과목초(legumes)는 Trifolium pratense, Medicago sative, Trifolium repens, Melilotus officinalis 및 Vicia villosa의 5종 수엽(樹葉, browse)으로 Quercus serrata Thunb., Prunus jamasakura Sieb., Quercus aliena Blume, Robinia pseudoaccacia 및 Pinus densiflora의 5종과 잡초(weeds)는 Artemisia princeps Pampanini, Erigeron canadensis, Alopecurus aegualis Sobolewski, Echinochloa crusgalli var. frumentacea(Roxb.) Wight 및 Rumex crispus의 5종을, 야초(native grasses)는 Zoysia japonica Steudel, Agropyron tsukushiense var. transiens(HACK) Ohwi., Arundinella hirta(Thunb.) Tanaka, Miscanthus sinensis Anderss 및 Phragmites comunis Trin의 5종 등 총 25종을 공시하였다. 시험축은 재래산양(남) 10두를 공시하였으며, 평균체중은 30.6kg이었다. 시료는 초종 당 건물기준으로 0.5kg씩 급여하였고 오전 8시부터 오후 8시까지 전북 남원시 운봉읍 소재 가축유전자원시험장 축사내에서 수행하였으며 시험결과는 다음과 같다. 공시시료의 조사료원별로 분석한 화학적 성분과 5건물소화율은 대체적으로 채취장소 초종, 생육단계 및 예취시기에 따라 차이를 보였다. 채식량, 채식비율 및 채식순위는 초종 및 수종에 따라 차이를 보였으며, 대체적으로 섬유소물질의 함량이 낮은 반면에 건물소화율이 높은 조사료를 더 즐겨 채식하는 양상이었다. 재래산양은 Quercus serrata Thunb.(졸참나무 잎, 500g)을 가장 즐겨 채식하였으며, 다음은 Quercus aliena Blume(갈참나무 잎, 441g), Trifolium repens(white clover, 433g), Pinus densiflora(소나무 잎, 417g) 순이었으며 다른 가축이 즐겨 먹지 않는 Pinus densiflora나 Artemisia princeps Pampanini(쑥)도 즐겨 채식하였다. 재래산양의 조사료원별 채식분포를 보면 수엽 29.9%, 두과목초 23%, 잡초 21.6%, 화본과목초 21.5% 및 야초 4.0%를 채식하였던 것으로 보아 채식습성은 수엽채식형(browser type)에 더 가까운 것으로 판단되었다. The object of this experiment was to investigate the food habits of Korean native goats fed with various roughage sources. The feeding trials were conducted at Chungnam National University and Unbong Animal Genetic Resources Station in 2007. The experimental roughages sources were five including 25 species in all; grass sources: 5 species (Lolium perenne, Festuca arundinacea, Poa pratensis, Agrostis alba and mixed grass, legume sources: 5 species (Trifolium pratense, Medicago sativa, Trifolium repens, Melilotus officinalis and Vicia villosa), browse sources: 5 species(Quercus serrata Thunb., Prunus jamasakura Sieb., Quercus aliena Blume, Robinia pseudoaccacia and Pinus densiflora), weed sources: 5 species(Artemisia princeps Pampanini, Erigeron canadensis, Alopecurus aegualis Sobolewski, Echinochloa crusgalli var. frumentacea (Roxb.) Wight and Rumex crispus), and native grass sources: 5 species(Zoysia japonica Steudel, Agropyron tsukushiense var. transiens(Hack) Ohwi., Arundinella hirta(Thunb.) Tanaka, Miscanthus sinensis Anderss and Phragmites comunis Trin). Ten Korean native goats were selected which had nearly the same body weight(average 30.6kg, 남) as experimental animals. Experimental roughages were prepared by 0.5kg per 1 species fed to Korean native goats, and the experiment was carried out from 08:00 to 20:00. The chemical composition and dry matter digestibility of each roughage source and species were significantly different at the sampling area, plant species, growth stages and cutting period (p<0.05). The Korean native goats ate more roughages which had low fibrous contents, but high dry matter digestibility. Among all the 25 species of roughages, the favorite intake species order by Korean native goats was observed like this: Quercus serrata Thunb., Quercus aliena Blume, Trifolium repens, and Pinus densiflora and Artemisia princeps Pampanini which was lower intake compared to other domestic herbivores. On the other hand, compared to each roughage source, total intake amount by Korean native goats was showed as browse(29.9%), legumes(23.0%), weeds(21.6%), grasses(21.5%) and native grasses(4.0%), respectively. Based on the result, the food habit of Korean native goats seems to be closer to browser type.

Relationship between the Time and Duration of Flowering in Several Woody Plants in Springtime

To clarify the relationship between the timing and the duration of flowering among populations, plants, and individual flowers, the dates of flower budding, flowering and deflowering were monitored for ten woody species from March 1 to June 30, in 2005, 2006 and 2007, in temperate deciduous forests at three sites of Namsan, and individual plants from seven woody species were monitored from March 1 to May 31, in 2006. Total durations of flower budding, flowering, and deflowering varied among the plant species. Three durations of these phenological stages of Stephanandra incisa were the longest (74 days, 109 days, and 101 days, respectively), and those of Prunus serrulata var. spontanea were the shortest (7 days, 7 days, and 4 days, respectively). For each species, phenological durations varied among years but were similar among the study sites in the same year. There was no relationship between flowering time and flowering duration on the population level. On the plant level, the duration of flower budding was over 11 days in all specie; S. incisa had the longest duration (73.3 days), and that of Styrax japonica was long as well (29.0 days), while that of Prunus leveilleana was the shortest (11.3 days). The longer the mean flower budding duration, the greater the difference among the plants within a species. The flowering duration of for S. incisa was 92.2 days, while that of Forsythia koreana was 27.2 days. The flowering durations of all other species were <TEX>$10{\sim}20$</TEX> days. The deflowering duration was 92.0 days in S. incisa and <15 days in all other species. Differences among the plants in deflowering duration were smaller than those of the other phenological stages. In the species that flowered in April, the correlation coefficient between the flowering duration and the first flowering date was negative and significant. However, in the species that flowered in May, the correlation between flowering duration and the first flowering date was not significant. For individual plants of all species except for S. alnifolia, the earlier the flowering time, the longer the flowering duration. Differences between flowering time and flowering duration across years were significant in six species.

Development of 13 EST-SSRs for Cerasus jamasakura and their transferability for Japanese flowering cherries

Simple sequence repeat (SSR) markers were developed for the flowering cherry Cerasus jamasakura (also known as Prunus jamasakura) using 31,995 expressed sequence tags (ESTs) from the NCBI database. Out of 96 of designed primer pairs, 63 showed clear PCR amplification and 13 of these revealed polymorphism in eight individuals sampled across the species’ range. The number of alleles detected and expected heterozygosity ranged from 1 to 8 and 0.000 to 0.833, respectively, when these 13 loci were examined in 23 individuals from a single population. For all except one of the lcoi, polymorphism was also detected in at least four of six other taxa of flowering cherries examined. The results show that the developed EST-SSRs are highly transferable, and that these markers are likely to be useful in studies of the population genetics of flowering cherries.

여러 가지 조사료를 급여한 꽃사슴(Servus nippon)의 채식습성에 관한 연구

본 연구는 2007년 3월부터 12월까지 충남대학교 부속사육장 및 전북 남원시 운봉읍 소재 가축유전자원시험장에서 수행하였다. 공시시료는 화본과목초(grasses)는 Lolium perenne, Festuca arundinacea, Poa pratensis, Agrostis alba 및 mixed grass의 5종과, 두과목초(legumes)는 Trifolium pratense, Medicago sativa, Trifolium repens, Melilotus officinalis 및 Vicia villosa의 5종, 수엽(browse)으로 Quercus serrata Thunb., Prunus jamasakura Sieb., Quercus aliena Blume, Robinia pseudoaccacia 및 Pinus densiflora의 5종과 잡초(weeds)는 Artemisia princeps Pampanini, Erigeron canadensis, Alopecurus aegualis Sobolewski, Echinochloa crusgalli var. frumentacea(Roxb.) Wight 및 Rumex crispus의 5종을, 야초(Weeds)는 Zoysia japonica Steudel, Agropyron tsukushiense var. transiens(HACK) Ohwi., Arundinella hirta(Thunb.) Tanaka, Miscanthus sinensis Anderss 및 Phragmites comunis Trin의 5종 등 총 25종을 공시하였다. 시험축은 꽃사슴(수컷) 5두를 공시하였으며, 평균체중은 92.5 kg이었다. 시료는 초종 당 건물기준으로 0.5 kg씩 급여하여 시험하였으로 시험결과는 다음과 같다. 공시시료의 조사료원별로 분석한 화학적 성분과 건물소화율은 대체적으로 채취장소, 초종, 생육단계 및 예취시기에 따라 차이를 보였다. 채식량, 채식비율 및 채식순위는 초종 및 수종에 따라 차이를 보였으며, 대체적으로 섬유소물질의 함량이 낮은 반면에 건물소화율이 높은 조사료를 더 즐겨 채식하는 양상을 나타내었다. 꽃사슴은 Quercus aliena Blume(갈참나무 잎, 500g)을 가장 즐겨 채식하였으며, 다음은 Prunus jamasakura Sieb.(벚나무 잎, 491g)과 Quercus serrata Thunb.(졸참나무 잎, 491g), Trifolium pratense(red clover, 481g) 순으로 즐겨 채식하였던 반면에, Phragmites comunis Trin(갈대, 8g)를 가장 적게 채식하였다. 꽃사슴의 채식습성은 수엽 36.5%, 두과목초 34.2%, 화본과목초 14.0%, 야초는 13.5% 및 잡초를 1.8% 채식하였던 것으로 보아 채식습성은 전형적인 수엽채식형(browser type)에 가깝다고 하겠다. The object of this experiment was to investigate the food habits of sika deer fed with various roughage sources. The feeding trials were conducted at Chungnam National University and Unbong Animal Genetic Resources Station in 2007. The experimental roughages sources were five including 25 species in all; grass sources; 5 species(Lolium perenne, Festuca arundinacea, Poa pratensis, Agrostis alba and mixed grass), legume sources; 5 species(Trifolium pratense, Medicago sativa, Trifolium repens, Melilotus officinalis and Vicia villosa), browse sources; 5 species(Quercus serrata Thunb., Prunus jamasakura Sieb., Quercus aliena Blume, Robinia pseudoaccacia and Pinus densiflora), weed sources; 5 species(Artemisia princeps Pampanini, Erigeron canadensis, Alopecurus aegualis Sobolewski, Echinochloa crusgalli var. frumentacea(Roxb.) Wight and Rumex crispus), and native grass sources; 5 species(Zoysia japonica Steudel, Agropyron tsukushiense var. transiens(Hack) Ohwi., Arundinella hirta(Thunb.) Tanaka, Miscanthus sinensis Anderss and Phragmites comunis Trin). Five sika deer were selected which had nearly the same body weight(average 92.5kg) as experimental animal. Experimental roughages were prepared by 0.5kg(DM basis) per 1 species fed to sika deer, and the experiment was carried out from 08:00 to the next day 06:00. The chemical composition and dry matter digestibility of each roughage source and species were significantly different at the sampling area, plant species, growth stages and cutting period. The sika deer ate more roughages which had low fibrous contents, but high dry matter digestibility. Among all the 25 species of roughages, the favorite intake species ranking by sika deer was observed like this: Quercus aliena Blume, Prunus jamasakura Sieb, Quercus serrata Thunb. and Trifolium pratense, respectively, and the lower intake species was Phragmites comunis Trin. On the other hand, compared to each roughage source, total intake amount by sika deer was showed as browse(36.5%), Legumes(34.2%), grasses(14.0%), native grasses(13.5%) and weeds(1.8%), respectively. Based on the result, the food habits of sika deer seems to be closer to typically browser type.

여러 가지 조사료를 급여한 유 산양 (Saanen)의 채식습성에 관한 연구

본 연구는 몇 가지 조사료원을 유 산양에 급여하였을 때 조사료의 중류에 따른 채식습성을 구명하고자 2007년 3월부터 10월까지 충남대학교 부속사육장에서 수행하였다. 공시시료는 화본과목초 (grasses)는 Lolium perenne, Festuca arundinacea, Poa pratensis, Agrostis alba 및 mixed grass (혼합목초)의 5종과, 두과목초(legumes)는 Trifolium pratense, Medicago sativa, Trifolium repens, Melilotus officinalis 및 Vicia villosa의 5종, 수엽(browse)으로 Quercus serrata Thunb., Prunus jamasakura Sieb., Quercus aliena Blume, Robinia pseudoaccacia 및 Pinus densiflora의 5종과 잡초 (weeds)는 Artemisia princeps Pampanini, Erigeron canadensis, Alopecurus aegualis Sobolewski, Echinochloa crusgalli var. frumentacea (Roxb.) Wight 및 Rumex crispus의 5종을, 야초 (Weeds)는 Zoysia japonica Steudel, Agropyron tsuku- shiense var. transiens (Hack) Ohwi., Arundinella hirta (Thunb.) Tanaka, Miscanthus sinensis Anderss 및 Phragmites comunis Trin의 5종 등 총 25종을 공시하였다. 시험축은 Saanen종 유 산양(female) 10두를 공시하였으며, 평균체중은 31 kg이었다. 시료는 초종 당 건물기준으로 0.5 kg씩 급여하였고 오전 9시부터 오후 6시까지 시험하였으며 시험결과는 다음과 같다. 공시시료의 조사료원별로 분석한 화학적성분과 건물소화율은 대체적으로 채취장소, 초종, 생육단계 및 예취시기에 따라 차이를 보였다. 채식량, 채식비율 및 채식순위는 초종 및 수종에 따라 차이를 보였으며, 섬유소물질의 함량이 낮고 건물소화율이 높은 조사료를 더 즐겨 채식하는 양상을 나타내었다. 공시된 25 초종 중 perennial ryegrass, tall fescue, red clover 순으로 즐겨 채식하였으며, 소리쟁이가 가장 기호성이 낮았다. 유 산양 (Saanen)은 화본과목초 (33.3%) 및 두과목초 (25.7%)를 총 59.0% 채식하였던 반면에 수엽은 19.6%, 잡초는 15.9%, 야초는 5.5%를 채식하였던 것으로 보아 채식습성은 초류채식형 (grazer type)에 더 가까운 것으로 판단된다. The object of this experiment was to investigate the food habits of dairy goats fed with various roughage sources. The experimental trials were conducted at Chungnam National University in 2007. The experimental roughages include five sources and 25 species in all; grass sources: 5 species (Lolium perenne, Festuca arundinacea, Poa pratensis, Agrostis alba and mixed grass, legume sources: 5 species (Trifolium pratense, Medicago sativa, Trifolium repens, Melilotus officinalis and Vicia villosa), browse sources : 5 species (Quercus serrata Thunb., Prunus jamasakura Sieb., Quercus aliena Blume, Robinia pseudoaccacia and Pinus densiflora), weed sources: 5 species (Artemisia princeps Pampanini, Erigeron canadensis, Alopecurus aegualis Sobolewski, Echinochloa crusgalli var. frumentacea (Roxb.) Wight and Rumex crispus), and native grass sources: 5 species (Zoysia japonica Steudel, Agropyron tsukushiense var. transiens (Hack) Ohwi., Arundinella hirta (Thunb.) Tanaka, Miscanthus sinensis Anderss and Phragmites comunis Trin). Ten dairy goats(Saanen) were selected which had nearly the same body weight(average 31kg). Experimental roughages were prepared by 0.5kg per 1 species fed to dairy goats, and the experiment was carried out from 09:00 to 18:00. The chemical composition and dry matter digestibility of each roughage source and species were significantly different at the sampling area, plant species, growth stages and cutting period. The dairy goats ate more roughages which had low fibrous contents, but high dry matter digestibility. Among all the 25 species of roughages, the favorite intake species order by dairy goat was observed like this: perennial ryegrass, tall fescue and red clover, respectively, and the lower intake species order was Rumex crispus. On the other hand, compared to each roughage source, total intake amount by dairy goats was showed as forage grasses (59.0%) which contained grasses(33.3%) and legumes (25.7%), browse (19.6%), weeds (15.9%) and native grasses (5.5%). Based on the result, the food intake type of dairy goats seems to be closer to grazer type.

Natural occurrence of Xylella fastidiosa in a commercial nursery in Maryland

Bacterial leaf scorch caused by Xylella fastidiosa is a serious problem in the landscape, but its importance in the nursery trade is undetermined. Therefore, a survey was conducted in 2003 and 2004 in a commercial wholesale and production nursery in Maryland to determine the natural occurrence of X. fastidiosa in nursery plants and surrounding vegetation using enzyme-linked immunosorbent and nested polymerase chain reaction assays specific for the bacterium. Xylella fastidiosa was associated with crape myrtle (Lagerstroemia indica), Japanese stewartia (Stewartia pseudocamellia), Schipka laurel (Prunus laurocerasus ‘Schipkaensis’), and Japanese flowering cherry (Prunus serrulata ‘Kwanzan’) in the nursery, as well as with mimosa (Albizia julibrissin) and sassafras (Sassafrass albidum) growing in the perimeter of the nursery. All were previously unknown hosts of the bacterium. Xylella fastidiosa was also detected in dogwood (Cornus florida) and willow oak (Quercus phellos) in the nursery, as well as in red oak (Quercus spp.), box-elder (Acer negundo), and wild grape (Vitis spp.) surrounding the nursery, previously reported hosts of the bacterium. The red oak and box-elder plants on the edge of the nursery showed leaf scorch symptoms and harboured high populations of the bacterium. However, the Xylella-positive nursery plants and other plants from the local environment were symptomless, and the bacterial populations were low. These data suggest that red oak and box-elder are sources of the X. fastidiosa in the nursery plants.

Phenological data series of cherry tree flowering in Kyoto, Japan, and its application to reconstruction of springtime temperatures since the 9th century

AbstractChanges in springtime temperature in Kyoto, Japan, since the 9th century were reconstructed, using the phenological data series for cherry tree (Prunus jamasakura), deduced from old diaries and chronicles. Phenological data for 732 years was made available by combining data from previous studies. The full‐flowering date of cherry trees fluctuates in accordance with temperature conditions during February and March. Full‐flowering dates were closely related to the March mean temperature by means of a temperature accumulation index, in which plant growth is considered to be an exponential function of temperature. Calibration enabled accurate estimation of temperatures in the instrumental period, after 1880; the root mean square error (RMSE) of temperature estimates was determined to be within 0.1 °C, after smoothing by local linear regression over time spans of 31 years. The results suggested the existence of four cold periods, 1330–1350, 1520–1550, 1670–1700, and 1825–1830, during which periods the estimated March mean temperature was 4–5 °C, about 3–4 °C lower than the present normal temperature. These cold periods coincided with the less extreme periods, known as the Wolf, Spoerer, Maunder, and Dalton minima, in the long‐term solar variation cycle, which has a periodicity of 150–250 years. The sunspot cycle length, a short‐term solar variation cycle, was also compared with the temperature estimates, with the result that a time lag of about 15 years was detected in the climatic temperature response to short‐term solar variation. Copyright © 2007 Royal Meteorological Society

Fruit phenology of Prunus jamasakura and the feeding habit of the Asiatic black bear as a seed disperser

AbstractWe investigated the relationship between the fruit phenology of Prunus jamasakura and the fruit‐feeding period of the Asiatic black bear (Ursus thibetanus). The purposes of this study were to determine (1) when bears feed on the fruit of P. jamasakura in relation to phenology; (2) whether ingestion damages seeds; and (3) how ingestion influences seed germination. We assessed the relationship between the phenology of fruit maturation (size, sugar concentration, color, persistence, and germination percentage) and the feeding period of bears in the field, as judged from bear shelves and claw marks. We also compared the germination percentage of seeds ingested by captive bears with that of uningested. Bears fed on the fruit from days 50 to 66 after flowering, when most of the fruits were on the tree and became large, the germination percentage of seeds increased, and the sugar concentration became high. Bears fed only on mature fruits and so obtained high‐quality nutrients. Germination tests showed that ingestion of fruits by the bears caused no physical damage to the seeds. Ingested seeds did not show a significant difference in germination percentage from seeds, whose pulp was artificially removed. These results indicate that bears are potentially effective dispersers from a qualitative perspective and, to some extent, from a quantitative perspective.

Antioxidative and Anticancer Activity of Extracts of Cherry (Prunus serrulata var. spontanea) Blossoms

Organic solvent (methanol, ethanol, and acetone) extracts and water extracts of cherry (Prunus serrulata var. spontanea) blossoms were prepared, and antioxidant activities of the extracts were evaluated. Methanolic CBE (100 microg/ml) showed the highest total phenol content (104.30 microM), radical scavenging activity (34.2%), and reducing power (0.391). The effect of CBE on DNA damage induced by H(2)O(2) in human leukocytes was evaluated by Comet assay. All CBE was a potent dose dependent inhibitor of DNA damage induced by 200 microM of H(2)O(2), methanolic CBE showed the most strong inhibition activity. The methanolic CBE of 500 microg/ml showed 38.8% inhibition against growth of human colon cancer cell line HT-29. These results indicated that cherry blossoms could provide valuable bioactive materials.

Reconsideration of the Prunus serrulata complex (Rosaceae) and related taxa in eastern Asia

The Prunus serrulata complex with several infraspecific taxa, including P. jamasakura and P. leveilleana, is indigenous to eastern Asia. Although these taxa are very common, the taxonomic confusion surrounding this complex is reflected in the ambiguity shown by the various taxonomic treatments currently used. Patterns of intraspecific variation and recognition of taxa within the P. serrulata complex and its related species were investigated in 468 individuals using principal components analysis. Particular emphasis was placed on P. serrulata, P. jamasakura, and P. leveilleana because of their high degree of morphological intergradation and inconsistent circumscription in the various systematic treatments. Although morphological variation among different taxa of the P. serrulata complex was continuous for most reproductive and leaf characters, the related taxa (P. pseudocerasus, P. lannesiana f. albida, and P. sargentii) were found to be distinct based on the number of flowers per inflorescence and peduncle length. In general, the number of flowers per inflorescence, the flower size, peduncle length, and hair density on the pedicel were found to be characters of great taxonomic value for most of the related taxa. However, there is not sufficient morphological evidence for the taxonomic splitting of P. serrulata to warrant the designation of varieties, with the exception of the pubescent taxon, P. serrulata var. pubesecens. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 154, 35–54.

Distribution of S-alleles in island populations of flowering cherry, Prunus lannesiana var. speciosa

We surveyed the distribution of S-alleles in natural island populations of Prunus lannesiana var. speciosa sampled from seven sites on the Izu Peninsula and six Izu islands, Japan. The S-genotypes of sampled individuals were determined by Southern analysis of RFLPs generated by restriction enzyme digestion of genomic DNA, using cDNA of the S-RNase gene as a probe. All individuals were heterozygous, as expected under gametophytic self-incompatibility (GSI). Sixty-three S-alleles were observed in the species, but 12 private to the Izu Peninsula population seemed to be derived from related species, giving a total of 75. The estimated number of S-alleles in each population ranged from 26 to 62, and was inversely correlated with the respective population's distance from the Izu Peninsula, the closest point in the mainland to the islands. This geographical cline in the estimated numbers of S-alleles suggests that gene flow to and from the distant island populations was less frequent, and that the studied species has migrated from the mainland to the Izu islands. The genetic relationship at the S-locus among populations also gave an "isolation by distance" pattern. The genetic differentiation at the S-locus among the populations was very low (F(ST) = 0.014, p < 0.001). The number of S-alleles in the species did not seem to depend on genetic differences associated with population subdivisions. This might be due to the greater effective migration rates of S-alleles, as expected under balancing selection in GSI.

Pollen production in a planted community of Prunus lannesiana var. speciosa

Pollen production in a planted community of Prunus lannesiana var. speciosa

Pseudomonas syringae Diseases of Fruit Trees: Progress Toward Understanding and Control.

Pseudomonas syringae Diseases of Fruit Trees: Progress Toward Understanding and Control.