Identification and use of a wild plant with antimicrobial activity against Ralstonia solanacearum, the cause of bacterial wilt of potato

Fresh aerial tissue and roots of 14 wild plants in Okinawa prefecture were investigated for their antimicrobial activity against Ralstonia solanacearum , which causes bacterial wilt of potato. A 70% aqueous ethanol extract of fresh aerial tissue of Geranium carolinianum L. showed strong antimicrobial activity against R. solanacearum . This extract also showed antimicrobial activity against the pathogens causing common scab of potato and soil rot of sweet potato. The antimicrobial substance could be extracted with hot water, and was effective against R. solanacearum in soil. In the field test, a treatment combining incorporation of dried aerial tissue into the soil and solarization was highly effective for control of bacterial wilt of potato. These findings suggest that G. carolinianum L. could be used as a biological agent for the control of bacterial wilt of potato.     

Effects of loosing Aigamo ducks on the growth of rice plants, weeds, and the number of arthropods in paddy fields

Aigamo duck farming has been noticed as one of the techniques of environmental conservation agriculture. This study was carried out to investigate the effects of loosing Aigamo ducks on the growth and production of rice plants, the quantity of weeds and arthropods, and the balance of nitrogen (N) in paddy fields by changing the density of the Aigamo ducks. A paddy field was divided into three test plots: a 10-Aigamo-duck plot, a five-Aigamo-duck plot, and a weeding plot. The results show that the height, number of culms, and yield crops of the rice plants increased more in the 10-Aigamo-duck plot and the five-Aigamo-duck plot than that of the weeding plot. Millet ( Echinochloa oryzicola ) remained in both the Aigamo duck plots. The weeding plot was covered with monochoria ( Monochoria vaginalis ). In both the Aigamo duck plots, the outbreak of total arthropods was lower than that of the weeding plot, but the number of rice plants damaged by grass leaf rollers ( Cnaphalocrocis medinalis ) was increased. The number of spiders, regarded as useful insects, did not differ that much between the experimental plots. The N content of the soil did not differ as an effect of loosing the Aigamo ducks. The rice plants in the 10-Aigamo-duck plot absorbed more N than the rice plants in the other plots.     

奶牛饲喂不同精粗料比TMR对排泄粪尿和氮磷的影响

将18头荷斯坦产奶牛随机分为试验6组,每组3头,试验Ⅰ～Ⅵ组奶牛依次饲喂不同精粗料比(精料:粗料)的TMR1 (20∶80)、TMR2(30∶70)、TMR3 (40∶60)、TMR4 (50∶50)、TMR5 (60∶40)、TMR6 (70∶30)的日粮,探讨不同精粗料比TMR对奶牛粪尿、N、P的排泄量和CH4释放...     

奶牛饲喂不同精粗料比TMR对排泄粪尿和氮磷的影响

将18头荷斯坦产奶牛随机分为试验6组,每组3头,试验Ⅰ～Ⅵ组奶牛依次饲喂不同精粗料比（精料：粗料）的TMR1（20∶80）、TMR2（30∶70）、TMR3（40∶60）、TMR4（50∶50）、TMR5（60∶40）、TMR6（70∶30）的日粮,探讨不同精粗料比TMR对奶牛粪尿、N、P的排泄量和CH4释放量的影响。结果,饲喂TMR4与饲喂TMR1和TMR6的奶牛相比,每头奶牛每年CH4释放量减少15.20Kg和89.84Kg;粪便排泄量减少1.37t和1.41t;N降低3.71kg和17.50kg;P减少2.59kg和4.07kg,比TMR1FCM提高10.54%（P〈0.05）;乳脂率增加9.67%（P〈0.05）;乳糖增加7.26%（P〈0.05）,能减少奶牛对土壤水源及空气的污染,提高奶牛的生态效益和经济效益。     

高亚油酸低亚麻酸甘蓝型油菜育种材料的选育

运用毛细管气相色谱仪对无芥酸甘蓝型油菜品种lisadra(B.napusL.cv.)和高亚油酸、低亚麻酸芥菜型油菜JN63（B.juncea)杂交产生的F4代各株系进行了脂肪酸组分分析。并选出其中5个优良的株系,采用半粒法对各种系单株的脂肪酸组分进行了分析,在这些单株中发现一个高油酸、无亚麻酸、无芥酸的特殊材料464－5－1－5,以及一系列的高油酸、高亚油酸、低亚麻酸、无芥酸含量的材料,为油菜的品质育种提供了很好的育种材料。     

Identification and activity of ethyl gallate as an antimicrobial compound produced by Geranium carolinianum

We isolated an antimicrobial compound from the aerial tissue of Geranium carolinianum and identified it as ethyl 3, 4, 5-trihydroxy benzoate (ethyl gallate) by ¹H-NMR and ¹³C-NMR and gas chromatography–mass spectrometry. The antimicrobial activity of ethyl gallate against three potato pathogens was assayed by the paper disk method. The activity against Ralstonia solanacerum , Streptomyces scabies , and Streptomyces acidiscabies was observed at concentrations >200, >300, and >300 µg disk⁻¹, respectively. These results suggest that the antimicrobial activity of Geranium carolinianum against soil-borne plant disease pathogens is partly related to ethyl gallate.     

CONTRAST-ENHANCED ULTRASONOGRAPHY FOR CHARACTERIZATION OF CANINE FOCAL LIVER LESIONS

In six normal beagles and 27 dogs with spontaneous focal or multifocal liver lesions, contrast-enhanced ultrasonography using Sonazoid^® was performed. Sonazoid^® is a newly developed second-generation contrast agent with the ability to be used for real-time contrast imaging along with parenchymal imaging. An appropriate protocol for the evaluation of all three phases (arterial, portal, and parenchymal) was established based on the results for normal beagles. By evaluation of the echogenicity of hepatic nodules during the arterial and parenchymal phases it was possible to differentiate malignant tumors from benign nodules with very high accuracy. In 15 of 16 dogs diagnosed as malignant tumors, nodules were clearly hypoechoic to the surrounding normal liver during the parenchymal phase. Additionally, malignant tumors had different echogenicity compared with the surrounding normal liver during the arterial phase in 14 of 15 dogs. In the portal phase, there were no characteristic findings. Contrast-enhanced ultrasonography with Sonazoid^® appears to improve the characterization of canine focal and multifocal hepatic lesions.     

Growth-dependent survival mechanisms during the early life of a temperate seabass (Lateolabrax japonicus): field test of the ‘growth–mortality’ hypothesis

Three concepts based on size, time and growth rate are contained in the functional mechanisms of the ‘growth–mortality’ hypothesis, and are known as the ‘bigger is better’, ‘stage duration’ and ‘growth-selective predation’ hypotheses, respectively. Although it is sufficiently documented in fishes that faster growing and bigger larvae selectively survive, synergistic operation of the three components of the ‘growth–mortality’ hypothesis within a species have received little attention. In this study, we have tested the components of the ‘growth–mortality’ hypothesis based on the growth characteristics of original population (OP) and survivors (SV) of Japanese seabass (JSB) Lateolabrax japonicus. Larval and juvenile JSB were repeatedly sampled from the Tango Sea in 2007 and 2008. Otoliths from larvae and juveniles were analyzed to produce back-calculated daily records of size-at-age and growth rate, and were compared between OP and SV. Selective survival for fast-growing and bigger larvae was evident, and our results strongly support the ‘bigger is better’ hypothesis as well as the ‘growth-selective predation’ hypothesis. Growth rates of the individuals that metamorphosed into juveniles had significantly faster growth rates than non-metamorphosing larvae older than 48 days, the minimum age for metamorphosis, suggesting a clear relationship between growth rates and the timing of metamorphosis. On average, SV completed the larval stage ∼13 days earlier than those of OP, supporting the ‘stage duration’ hypothesis. Thus, SV of JSB exhibited traits consistent with all aspects of the ‘growth–mortality’ hypothesis: faster growth, bigger size-at-age, and shorter larval stage duration (LSD), i.e., larvae with faster growth, bigger size-at-age and a shorter LSD selectively survived the larval period. Although maternal influence on growth and survival was evident, factors that regulate growth–mortality mechanisms remain to be explored for JSB.     

QUANTITATIVE CONTRAST-ENHANCED ULTRASONOGRAPHY OF CANINE SPLEEN

Contrast-enhanced ultrasonography has an important role in the detection of tumors in humans. The second-generation contrast agent Sonazoid has the ability of real-time contrast imaging along with parenchymal imaging. The purposes of this study were to determine the effect and duration of Sonazoid on the changes in gray-scale enhancement of canine spleen and to establish an appropriate protocol for contrast-enhanced ultrasonography of canine spleen. Six healthy beagles were injected with an intravenous bolus of Sonazoid. In the spleen parenchyma, the enhancement was maintained up to 30 min after injection. Moreover, for 5–22 s after injection, gray-scale enhancement of splenic arteries afforded arterial imaging. Perfusion of the kidney may be investigated from 3.6 s to 3.5 min after injection of Sonazoid. These results suggest that Sonazoid is applicable to canine spleen parenchymal imaging and that the optimal time for the parenchymal imaging is 7–30 min after injection. The findings of this quantitative study should prove useful in the evaluation of diffuse or focal splenic and renal diseases in dogs.