Variation in seed production among years and among individuals in 11 broadleaf tree species in northern Japan     

Michiyasu Yasaka  Mika Takiya  Ichiro Watanabe  Yasuyuki Oono  Norio Mizui 《Journal of Forest Research》2008,13(2):83-88

Seed production is the most problematic part of tree regeneration and is the least amenable to control by silvicultural management. Understanding variability in seed production among years and among trees will allow better planning of seed collection for seedling production and natural regeneration. We estimated the extent of variability in seed production among years and within years among individual trees. Specifically, we measured individual annual seed production in 11 woody species in Hokkaido, northern Japan. We analyzed the coefficient of variation (CV) of seed production among years and among individual trees. We used population- and individual-based CVs (CV_pt and ) to estimate the variability in seed production among individual trees. Alnus hirsuta, in which these CVs among trees were maximal, will require further analyses of the spatial patterns of seed production among individual trees. Additionally, we used population- and individual-based CVs (CV_py and ) to estimate the variability in seed production among years. The was statistically higher than in 2 of the 11 species: Betula maximowicziana and Sorbus alnifolia. Activities for the regeneration of these species should regard the annual variation in seed production as more important than individual variation. For the nine species in which was similar to even if seed production by specific trees was not sufficient for regeneration in a particular year, other trees or stands often had high seed production in that year. We discuss the relative importance of annual and individual variability in determining efficient methods for artificial and natural regeneration of these woody plant species.  相似文献   

Airborne basidiospores as an inoculum source of <Emphasis Type="Italic">Typhula variabilis</Emphasis> and the effect of hilling on the incidence of Typhula winter rot of carrots     

Sachiko Ikeda  Tamotsu Hoshino  Naoyuki Matsumoto  Norio Kondo 《Journal of General Plant Pathology》2017,83(1):46-50

Typhula winter rot on overwintering carrots caused by Typhula variabilis is a newly confirmed disease, and no practical control measure is yet available. To develop a control method, here we researched the infection period of T. variabilis and the time that winter rot appeared on carrots. Using spore traps, we found that basidiospore rain occurred from September to November before snowfall in Memuro, Hokkaido. In addition, carrot leaves collected in autumn had already been infected by T. variabilis. These epidemiological investigations revealed that the pathogen releases basidiospores to infect carrot leaves before snow cover, resulting in root decay under snow. An effective control method was then developed to avoid direct contact of basidiospores of T. variabilis with plant tops by covering the plants with soil in autumn. Thus, the percentage of rotted roots was reduced to about half.  相似文献   

Effect of exposure to low salinity water on plasma ion regulation and survival rates in artificially wounded devil stinger <Emphasis Type="Italic">Inimicus japonicus</Emphasis>     

Osamu Kawaguchi  Anise Midooka  Yuji Iwamoto  Takaya Kudoh  Yoshisuke Iida  Norio Nagao  Takuya Matsumoto 《Fisheries Science》2018,84(3):477-484

We investigated the effect of exposure to low salinity water on plasma ion regulation and survival rates in artificially wounded devil stinger Inimicus japonicus. All fishes survived in 33% seawater (SW), while survival rate in 100% SW was 5.1% at 24 h. In 100% SW, plasma Na⁺, K⁺, Mg²⁺, and Ca²⁺ concentrations significantly increased to 238?±?49.9, 9.6?±?2.4, 15.1?±?3.5 and 5.0?±?0.7 mmol/l at 6 h, respectively; the gill Na⁺/K⁺–ATPase (NKA) activity was almost stable, although only one fish survived to 24 h. In 33% SW, plasma Na⁺ and K⁺ concentrations remained at the same level, and plasma Mg²⁺ and Ca²⁺ concentrations gradually increased to 16.2?±?0.7 and 4.5?±?0.2 mmol/l until 24 h, respectively. The NKA activity significantly increased to 5.1?±?1.1 µmol ADP/mg protein per h at 6 h. A positive correlation was observed between the wound surface area against body weight and the plasma ion concentrations, although no difference was observed in the restoration rate of the wounded area between 100 and 33% SW. These results indicate that exposure of wounded fish to low salinity water improves survivability by favoring plasma ion regulation without influencing the restoration rate.  相似文献   

Winter habitat of Xylophilus ampelinus,the cause of bacterial blight of grapevine,in Japan     

Tsutomu Komatsu  Norio Kondo 《Journal of General Plant Pathology》2015,81(3):237-242

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Mapping a gene conferring resistance to <Emphasis Type="Italic">Wheat yellow mosaic virus</Emphasis> in European winter wheat cultivar ‘Ibis’ (<Emphasis Type="Italic">Triticum aestivum</Emphasis> L.)     

Zenta Nishio  Hisayo Kojima  Akiyo Hayata  Norio Iriki  Tadashi Tabiki  Miwako Ito  Hiroaki Yamauchi  Timothy D. Murray 《Euphytica》2010,176(2):223-229

Wheat yellow mosaic, caused by Wheat yellow mosaic virus (WYMV), is one of the most devastating soil-borne diseases of winter wheat (Triticum aestivum L.) in Japan. Yellow-striped leaves and stunted spring growth, symptomatic of WYMV infection, result in severe yield loss. A new putative WYMV resistance gene in the European wheat cultivar ‘Ibis’ was mapped in the cluster of microsatellite markers including Xcfd16, Xwmc41, Xcfd168 and Xwmc181 on the long arm of chromosome 2D at the distances of 2.0 cM, 4.0 cM, 7.1 cM and 12.4 cM, respectively. WYMV-resistant cultivars contained a common haplotype of the four markers, whereas moderately susceptible and susceptible cultivars did not. These results should be useful in marker-assisted selection for WYMV resistance in wheat.  相似文献   

Seasonal variation of paulownia witches’-broom phytoplasma in paulownia trees and distribution of the disease in the Tohoku district of Japan     

Hitoshi Nakamura  Shigeto Ohgake  Norio Sahashi  Nobuyuki Yoshikawa  Takanori Kubono  Tsuyoshi Takahashi 《Journal of Forest Research》1998,3(1):39-42

Seasonal variation of paulownia witches’-broom (PWB) phytoplasma within different organs (leaves, branch and trunk bark and roots) in paulownia trees was investigated by the amplification of a PWB-specific DNA fragment by the polymerase chain reaction (PCR). In leaf samples, PWB phytoplasma was first detected in June and the incidence gradually increased. On the other hand, the PWB was detected at relatively low incidence in branch bark, trunk bark and roots and the incidence did not change among seasons. A survey of PWB in 27 fields in the Tohoku district of Japan showed that malformed flower buds were observed in paulownia trees in almost all of the fields. PWB-phytoplasma was also detected by PCR from paulownia trees in almost all of the fields in Iwate and Fukushima Prefectures. The frequencies of trees in which phytoplasma was detected by PCR were higher than those in which symptoms were observed. These results indicated that PCR amplification of a PWB-specific DNA fragment is an effective tool for practical diagnose and that PWB is widely distributed in the Tohoku district of Japan.  相似文献   

Changes in the plasma levels of several bone markers in newborn calves during the first two days of life     

Kaoru HATATE  Kazuhiko SHINYA  Asako MATSUO-SATO  Shuichi SASAKI  Bhuminand DEVKOTA  Masahiro TAKAHASHI  Toichi HIRATA  Norio YAMAGISHI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(2):337-340

The fluctuations in the plasma levels of several bone markers were investigated in newborn calves. Experiment 1 monitored the postnatal changes in the plasma levels of tartrate-resistant acid phosphatase isoform 5b (TRAP5b), total alkaline phosphatase (t-ALP) and bone-specific alkaline phosphatase (BAP) in four calves. These markers increased significantly from 9−20 hr after the first colostrum-suckling compared with the values immediately after birth. Experiment 2 evaluated changes in the plasma TRAP5b, t-ALP, BAP and type I collagen cross-linked N-telopeptide (NTx) levels within 2 days post-birth in five calves with successful passive immunization via colostrum (non-deficient group) and five others with poor colostrum intake (deficient group). The non-deficient group had significantly higher plasma levels of the four parameters around 12 hr of life compared with the deficient group. The results suggest that the increase in plasma bone markers in calves in the first day of life is related to the colostrum intake.  相似文献   

Dehydrochlorination of p,p′-DDT by cultured cells derived from ovarian tissues of Culex pipiens var. molestus     

Masanori Yoshida  Toshio Fujita  Norio Kurihara  Minoru Nakajima 《Pesticide biochemistry and physiology》1985,23(1):1-6

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Studies on BHC isomers and related compounds: Penetration and translocation of BHC isomers in the cockroach and their correlation with physicochemical properties     

Norio Kurihara  Matazaemon Uchida  Toshio Fujita  Minoru Nakajima 《Pesticide biochemistry and physiology》1974,4(1):12-18

Penetration of BHC isomers through the integument of Periplaneta americana (L.) is a composite of several first-order events. Translocation and accumulation in the head appears to be a zero-order function. The correlation of some of the biological properties with physicochemical properties such as partition coefficients and binding constants are discussed.  相似文献   

Comparative insecticidal activities and metabolic rates of lindane and its hexadeuterio-analog     

Keiji Tanaka  Norio Kurihara  Minoru Nakajima 《Pesticide biochemistry and physiology》1976,6(4):386-391

Hexadeuterio-lindane(γ-BHC-d₆) was several times as toxic as lindane against the mosquito (Culex pipiens pallens), house fly (Musca domestica), German cockroach (Blattella germanica) and American cockroach (Periplaneta americana). The neuroexcitatory activity of these two compounds did not differ. Lindane was considerably synergized by piperonyl butoxide, but lindane-d₆ was not. A large isotope effect was observed in the in vivo breakdown of lindane-d₆. Thus, the intrinsic toxicities of both compounds are equivalent. The difference in insecticidal activity seems to be due to the different rates of detoxifying biodegradation caused by the kinetic deuterium isotope effect.  相似文献