Foot rot disease of sweet potato in Japan caused by Diaporthe destruens: first report,pathogenicity and taxonomy

Journal of General Plant Pathology - Foot rot, also known as stem rot or tuber-root rot syndrome, on sweet potato occurs in sweet potato fields in Okinawa, Japan. Isolates of one fungal species...     

水冬瓜油的碱炼工艺研究

比较了NaOH和Na2CO3对水冬瓜油(酸值22 mg/g)的碱炼效果,并应用正交和单因子试验,分析了Na2CO3溶液浓度、反应温度、反应搅拌强度和水洗温度4种因子对水冬瓜油碱炼降酸效果的影响,确定了碱炼降酸的最佳Na2CO3用量和Na2CO3碱炼水冬瓜油的最优工艺条件。结果表明,Na2CO3碱炼效果优于NaOH;以碱炼油的得率和酸值为指标,Na2CO3碱炼水冬瓜油的最佳反应条件为:Na2CO3水溶液浓度为170 g/L,反应温度为75℃,搅拌速度为100 r/min,水洗温度为80℃,固体Na2CO3用量为105 g/kg;在此条件下,水冬瓜毛油的酸值可降至1mg/g以下,可作为碱催化酯交换法制备生物柴油的原料。     

Seasonal fluctuation of invasive flatworm predation pressure on land snails: Implications for the range expansion and impacts of invasive species

Introduction of the snail-eating flatworm Platydemus manokwari has caused extinction and decline of native land snails on tropical and subtropical islands. As the factors influencing flatworm predation pressure on land snails remain unclear, I examined the effects of seasonal variation in flatworm predation pressure on land snail survival in the wild on a subtropical island. I also examined the feeding activities of P. manokwari under laboratory conditions. Survival rates of land snails experimentally placed on the forest floor for 7 days ranged from 0% to 100% among seasons on the oceanic island Chichijima [Ogasawara (Bonin) Islands]. More than 90% of snails were killed by P. manokwari within 7 days in the period from July to November, while less than 40% of snails were killed in other months. Snail mortality rate (0-100%) attributable to P. manokwari was positively correlated with mean temperature (17.1-27.3 °C) in the study area. Laboratory experiments showed that low temperature influenced snail survival and regulated feeding activity of P. manokwari. Laboratory experiments also suggested that high densities of P. manokwari may cause a rapid decline in snail survival. Therefore, ambient temperature and density of P. manokwari may regulate seasonal variations in predation pressure on land snails. Recent global warming may increase the probability of invasion and population establishment, and elevate the impacts of P. manokwari in temperate regions.     

Allelic frequencies and association with carcass traits of six genes in local subpopulations of Japanese Black cattle

Marker‐assisted selection (MAS) is expected to accelerate the genetic improvement of Japanese Black cattle. However, verification of the effects of the genes for MAS in different subpopulations is required prior to the application of MAS. In this study, we investigated the allelic frequencies and genotypic effects for carcass traits of six genes, which can be used in MAS, in eight local subpopulations. These genes are SCD, FASN and SREBP1, which are associated with the fatty acid composition of meat, and NCAPG, MC1R and F11, which are associated with carcass weight, coat color and blood coagulation abnormality, respectively. The frequencies of desirable alleles of SCD and FASN were relatively high and that of NCAPG was relatively low, and NCAPG was significantly associated with several carcass traits, including carcass weight. The proportions of genotypic variance explained by NCAPG to phenotypic variance were 4.83 for carcass weight. We thus confirmed that NCAPG is a useful marker for selection of carcass traits in these subpopulations. In addition, we found that the desirable alleles of six genes showed no negative effects on carcass traits. Therefore, selection using these genes to improve target traits should not have negative impacts on carcass traits.