Performance of Drought Tolerant Maize Varieties under Water Harvesting Technologies in the Coastal Region of Kenya

The average annual rainfall in coastal Kenya is 450–700?mm per annum in most places while the total annual evapotranspiration is 1200–1800?mm. In arid and semi-arid lands (ASALs), farmers grow maize varieties for medium to high rainfall zones without considering the need for water harvesting to enhance crop yield. To address the moisture constraint, a study was conducted to evaluate the performance of drought tolerant maize varieties under different water harvesting technologies (Zai pits, tied ridges and conventional). The treatments were laid out in a split - plot design with water harvesting methods as the main plots and maize varieties as the sub-plots. The response of four maize varieties (DK8031, DUMA 43, KDV1 and PH4) to three water harvesting technologies was evaluated. Variety Duma 43 produced the highest grain yield (P < 0.05) compared to the other varieties whereas yields for Zai pits and tied ridges were higher (P < 0.05) than for conventional treatment. Economic analysis revealed a higher gross margin for tied ridges than for Zai pits. Conventional planting showed a negative gross margin under the ASAL conditions. The variety DUMA 43 was selected for yield and cob size components whereas PH4 was selected for grain recovery when pounded and high stover biomass.     

Histopathological changes of the spinal cord and motor neuron dynamics in SOD1 Tg mice

We analyzed the histopathological changes and the number of motor neurons (MNs) in the lumbar spinal cord of Cu/Zn superoxide dismutase transgenic (SOD1^G93ATg) mice, which are frequently used as a disease model of amyotrophic lateral sclerosis (ALS). In SOD1^G93ATg mice, hyaline inclusions and foamy vacuoles in the neuronal cell body were observed at 7 weeks of age before neurologic symptoms, and large vacuoles, spheroid formation, and nerve cell aggregation became prominent after 13 weeks of age. The number of healthy MNs was 28.7 to 37.1 cells/animal in wild-type mice and 9.3 to 13.6 cells/animal in transgenic (Tg) mice. Furthermore, the number of MNs, including degenerative neurons, in Tg mice was 27.3–36.1 cells/animal at 18 weeks of age and 17.8–19.6 cells/animal at 21 weeks of age. The present results provide useful information for the development of drugs in ALS treatment.     

Morphological and molecular characterization for a Japanese isolate of tomato powdery mildew Oidium neolycopersici and its host range

 A single conidium of tomato powdery mildew was isolated from heavily infected leaves of tomato (cv. Moneymaker) grown in the greenhouse of Kinki University, Nara Prefecture, Japan. It was successively multiplied so the morphological and taxonomic characteristics of the pathogen and its host range under high humidity conditions could be analyzed. The isolate KTP-01 of the tomato powdery mildew optimally developed infection structures at 25°C under continuous illumination of 3500 lx. More than 90% of the conidia germinated and developed moderately lobed appressoria. After forming haustoria, the pathogen elongated secondary hyphae from both appressoria and conidia. The hyphae attached to leaf surfaces by several pairs of appressoria and produced conidiophores with noncatenated conidia. In addition to its morphological similarity to Oidium neolycopersici, the phylogenetic analysis (based on the sequence of internal transcribed spacer regions of rDNA) revealed that KTP-01 could be classified into the same cluster group as O. neolycopersici. In host range studies, KTP-01 produced abundant conidia on the foliage of all tomato cultivars tested and tobacco (Nicotiana tabacum), and it developed faint colonies accompanied by necrosis on leaves of potato (Solanum tuberosum), red pepper (Capsicum annuum), petunia (Petunia × hybrida), and eggplant (S. melongena). The pathogen did not infect other plant species including Cucurubitaceae plants, which have been reported to be susceptible to some foreign isolates. Thus, the present isolate of the tomato powdery mildew was assigned as O. neolycopersici, a pathotype different from foreign isolates of the pathogen. Received: December 5, 2002 / Accepted: December 26, 2002 Acknowledgments This work was supported in part by a Grant-in-Aid (12660050) from the Ministry of Education, Culture, Sports, Science, and Technology of Japan. We express our deepest thanks to professor Dr. Y. Sato, Toyama Prefectural University, for his kind and valuable suggestion on taxonomic analysis of the powdery mildew pathogen described in the present study.     

Pathogenic Races of Phakopsora pachyrhizi on Soybean and Wild Host Plants Collected in Japan

A total of 45 single uredinial isolates of Phakopsora pachyrhizi were collected from rust-infected soybean and wild host plants (Pueraria lobata and G. soja ) at different localities in central and southwestern Japan. Eighteen pathogenic races were identified using a set of differential varieties composed of nine cultivars of soybean and two accession lines of G. soja. Nine and 11 races were found on soybean and wild host plants, respectively. Two races were common to soybean and wild host plants. Received 27 April 2001/ Accepted in revised form 22 August 2001     

Ex Ovo Culture System for Avian Embryos and its Application

Ex ovo culture of avian embryos can be applied not only to embryology but also to various fields of basic research such as embryo manipulation, toxicology, and regenerative medicine. The windowing method, which facilitates various manipulations and observations by opening a hole in one part of the eggshell, and culture systems using surrogate eggshells, are widely used. Despite this, biology lessons in high schools cover shell-less culture systems, which involve the development of avian embryos in artificial vessels, such as rice bowls, without using surrogate eggshells. However, as embryo development stops at its early stages in this method, it is not possible to continuously observe the development of the embryo. This led to attempts to develop an embryo culture method using a complete artificial culture vessel that does not use surrogate eggshells, and Kamihira et al. (1998) succeeded in hatching quail embryos in an artificial culture vessel using polytetrafluoroethylene membranes. In addition, Tahara succeeded in hatching chick embryos in artificial culture vessels that used cling film made of polymethylpentene and reported their detailed methodology (Tahara and Obara, 2014). These technologies are being applied not only to school education but also to various fields of research.     

Over-winter weight dynamics in supplementally fed free-ranging sika deer (Cervus nippon)

Continuous body weight dynamics in supplementally fed free-ranging sika deer (Cervus nippon) during the three consecutive overwinters (from January to April), 1992–1994 were surveyed. Almost all individuals lost weight continuously throughout each winter (adult deer 5–13%; young deer 3–19%) and several deer lost weight even in April. Weight gain after loss began in the mid-April when ambient temperature increased and when plant growth began. Weight dynamics varied according to sex, age and reproductive status. Adult deer showed significant large weight loss than the young. Young deer lost weight (calves 18±11 g/day, yearling and two-year-olds 27±29 g/day) more slowly than the adults (65±23 g/day). Following this study of over-winter body weight dynamics, it seems that early springs are the most critical periods for the survival of free-ranging sika deer because of their poor nutritional condition. A portion of this report was presented at the 106th Annual Meeting of the Japanese Forestry Society (1994).     

Diamond and pore structure observed in wood charcoal

Conclusions Various carbon structures were observed in the wood charcoal sample: the well known pyrolytic graphite layers, onion-like particles, and diamond structure. It is suggested that wood charcoal carbonized at 700°C is a complex of various carbon structures. The pore structure was observed by electron microscopy, and it is supposed that the microstructure and pores are closely related. Further study of the microstructure during the carbonization process of charcoal is necessary to better understand the characteristic functions of wood charcoal for utilizing it as a source of carbon material.A summary of this study was presented at the 51st annual meeting of the Japan Wood Research Society, Tokyo, April 2001, and the 50th annual meeting of the Society of Materials Science, Osaka, May 2001     

Confirming a major QTL and finding additional loci responsible for field resistance to brown spot (Bipolaris oryzae) in rice

Brown spot is a devastating rice disease. Quantitative resistance has been observed in local varieties (e.g., ‘Tadukan’), but no economically useful resistant variety has been bred. Using quantitative trait locus (QTL) analysis of recombinant inbred lines (RILs) from ‘Tadukan’ (resistant) × ‘Hinohikari’ (susceptible), we previously found three QTLs (qBS2, qBS9, and qBS11) that conferred resistance in seedlings in a greenhouse. To confirm their effect, the parents and later generations of RILs were transplanted into paddy fields where brown spot severely occurred. Three new resistance QTLs (qBSfR1, qBSfR4, and qBSfR11) were detected on chromosomes 1, 4, and 11, respectively. The ‘Tadukan’ alleles at qBSfR1 and qBSfR11 and the ‘Hinohikari’ allele at qBSfR4 increased resistance. The major QTL qBSfR11 coincided with qBS11 from the previous study, whereas qBSfR1 and qBSfR4 were new but neither qBS2 nor qBS9 were detected. To verify the qBSfR1 and qBSfR11 ‘Tadukan’ resistance alleles, near-isogenic lines (NILs) with one or both QTLs in a susceptible background (‘Koshihikari’) were evaluated under field conditions. NILs with qBSfR11 acquired significant field resistance; those with qBSfR1 did not. This confirms the effectiveness of qBSfR11. Genetic markers flanking qBSfR11 will be powerful tools for marker-assisted selection to improve brown spot resistance.