Maturational factors as indicators of egg quality in Japanese eel, Anguilla japonica

In order to identify maturational factors that can serve as indicators of egg quality in artificially matured Japanese eel, Anguilla japonica, maturation-promoting factor (MPF; consists of cdc2 and cyclin B) related proteins and chromosomes were examined. Mitogen-activated protein kinase (MAPK; 44 kDa band) and cdc2 (35 kDa and 34 kDa band) were detected. Chromosomes aligned on a vertical spindle appeared normal; however, chromosomes on a horizontal spindle and dispersed chromosomes seemed unusual.     

Changes in neurosteroid biosynthesis during sexual maturation of lacustrine sockeye salmon

It was demonstrated that pregnenolone (P5) and 17α-hydroxypregnenolone (17α-OH-P5) were identified as cholesterol metabolites in the brain and pituitary gland of lacustrine sockeye salmon (Oncorhynchus nerka) during sexual maturation. Moreover, 17α-OH-P5 was determined as the major cholesterol metabolite. The conversion of P5 to 17α-OH-P5 in the brain and pituitary gland showed a clear regional difference, and their productivity were dramatically changed during sexual maturation. From these data, it was suggested that steroid converting enzyme in the brain and pituitary gland of lacustrine sockeye salmon might be involved in brain region-dependent roles on sexual maturation.     

Rice (Oryza sativa L.) germplasm suitable for direct sowing under flooded soil surface

Summary Screening for rice germplasm which can establish seedling from flooded soil was conducted using 256 accessions of conserved germplasm from the International Rice Germplasm Center (IRGC) and 404 accessions from the International Network for Genetic Evaluation for Rice (INGER), IRRI. IRGC germplasm represented broad genetic diversity while INGER germplasm involved desirable agronomic characters. Seeds germinated for 2 d were planted at 25 mm depth in seedling trays. The trays were then submerged to a depth of 30–50 mm. Seedling establishment was evaluated by analyzing leaf development, seedling height, and percentage establishment 15 d after planting. Eight percent and 2% of IRGC and INGER germplasm, respectively, were identified statistically as superior to the control semidwarf IR varieties. Among the superior germplasm were those from Northeast India and Bangladesh which were adapted to deepwater and early summer rainfed lowland cultures. These could be utilized as parents in breeding programs which aim to develop varieties suitable for direct seeding technology (i.e., germinated seeds are sown under the surface of flooded soil).     

Correction: QTL mapping under salt stress in rice using a Kalarata–Azucena population

Euphytica - The color of flour and its end-use products is an important quality trait of wheat. Understanding the genetic basis of this trait is essential for improving wheat quality. In this...     

Conversion of chromosome-specific RAPDs into SCAR-based anchor markers for onion linkage maps and its application to genetic analyses in other Allium species

Integration of previously developed Allium cepa linkage maps requires the availability of anchor markers for each of the eight chromosomes of shallot (A. cepa L. common group Aggregatum). To this end, eight RAPD markers originating from our previous research were converted into SCAR markers via cloning and sequencing of RAPD amplicons and designing of 24-mer oligonucleotide primers. Of the eight pairs of SCAR primers, seven resulted in the amplification of single bands of the original RAPDs, and the remaining primer set amplified an additional band. The results of Southern hybridization using RAPD amplicons from genomic DNA of Japanese bunching onion (Allium fistulosum L.)—shallot monosomic addition lines indicated that five SCAR markers were single shallot chromosome-specific markers and were not detected in genomic DNA of A. fistulosum. The eight SCAR primer pairs were applied to other Allium species and exhibited three types of amplification profiles, namely RAPD amplicons observed only in shallot, in shallot and Allium vavilovii, and in several Allium species. A mapping study using 65 F₂ plants generated by the selfing of one interspecific cross A. cepa × Allium roylei individual integrated the SCAR marker SAOE17₅₀₀ into chromosome 5 as expected. The results of the present study show that the eight SCAR primer sets specific to shallot can facilitate the mapping in A. cepa and can also serve as anchor points between maps of different Allium species.     

UV-B irradiation retards chlorophyll degradation in lime (Citrus latifolia Tan.) fruit

Peel yellowing is a major postharvest problem of lime fruit. Research was conducted to control peel yellowing by UV-B irradiation. Mature green lime fruit were irradiated with UV-B doses at 0 (control), 8.8, and 13.2 kJ m^?2 and then stored at 25 °C in darkness. UV-B treatment at 8.8 kJ m^?2 efficiently delayed the decrease of chlorophyll content. A high level of chlorophyllide a accumulated in mature green fruit and then gradually decreased with the progress of peel yellowing. The chlorophyllide a level was higher in 8.8 kJ m^?2 UV-B-treated fruit than it was in the controls. The pheophorbide a level declined in lime fruit treated with 8.8 kJ m^?2 UV-B, especially during the development of yellowing. In addition, the pheophytin a level increased by 8.8 kJ m^?2 UV-B treatment at the late period of storage. We concluded that UV-B treatment effectively suppressed chlorophyll degradation in mature green lime during storage, which suggests that UV-B irradiation is a usable method for prolonging the postharvest life of lime fruit.     

Comparison of various reproductive status in Sika deer (Cervus nippon) using fecal steroid analysis

The feasibility of fecal steroid analysis for pregnancy diagnosis and sex determination were tested in sika deer (Cervus nippon). Feces were collected from captive sika deer in June (non-breeding season and late-pregnancy period) and October (breeding season), and also from the rectum of 24 female sika deer (19 pregnant and 5 non-pregnant females) shot as part of programs for population control in February and March (mid-pregnancy period). In mid- and late-pregnancy periods, fecal progesterone concentrations were significantly higher in pregnant female than in male and non-pregnant female deer. In October, fecal testosterone concentrations were higher in adult male deer, and no difference was found between young males and females. These results suggest that fecal steroid analysis would be a useful means for estimating pregnancy status and for detecting adult male among wild deer.     

Recovery of duodenal villi and cells in chickens refed protein, carbohydrate and fat

1. To clarify how histological recovery of villi and cells would be affected after refeeding single nutrients such as protein, carbohydrate and fat, male chickens were divided as follows: (1) intact control fed ad libitum a commercial finisher mash diet (CP, 140 g; ME, 11.71 MJ/kg, ALM), (2) 3 d feed withdrawal (FW), (3) FW followed by one day ad libitum free access to the mash diet (FW-ALM), and FW followed by one day force-feeding of (4) a commercial finisher pellet diet (FW-FFM) and an isocaloric diet of (5) a protein (FW-FFP), (6) a carbohydrate (FW-FFC) or (7) a fat (FW-FFF). 2. After refeeding, the formula diet groups increased in villus height and villus area and tended to increase in cell area and cell mitosis. Furthermore, flat cells on the villus tip in the F group developed to dome-shaped cells. This suggests that nutritionally well-balanced diets can induce histological recovery at villus and cellular levels. 3. Not all of the single nutrient groups recovered to the extent of the formula diet groups in all light microscopic variables after refeeding, suggesting that a single nutrient cannot induce histological recovery of the villus. 4. However, the dome-shaped cells were more distributed on the villus tip in these single nutrient groups than in the well-balanced formula diet groups, although cell diameter of the former groups was smaller than that of the latter. This suggests that the single nutrients would be effectively absorbed from cells and can induce histological recovery at the cellular level.     

Influence of Amylose Content on Cookie and Sponge Cake Quality and Solvent Retention Capacities in Wheat Flour

Reduced amylose wheat (Triticum æstivum L.) produces better quality noodles and bread less prone to going stale, while little is known about the relationships between amylose content and the quality of soft wheat baking products such as sugar snap cookies (SSC) and Japanese sponge cakes (JSC). Near‐isogenic lines developed from wheat cultivar Norin 61, differing in their level of granule‐bound starch synthase (Wx protein) activity, were used to produce wheat grains and ultimately flours of different amylose contents. These were tested with regard to their effect on soft wheat baking quality and solvent retention capacities (SRC). Amylose content was strongly correlated to cookie diameter (r = 0.969, P < 0.001) and cake volume (r = 0.976, P < 0.001), indicating that the soft wheat baking quality associated with SSC diameter and JSC volume were improved by an incremental increases in amylose content. Among the four kinds of SRC tests (water, sodium carbonate, sucrose and lactic acid), the water SRC test showed the highest correlation with amylose content, SSC diameter, and JSC volume. When the regression analysis was conducted between the nonwaxy and partial waxy isogenic lines that are available in commercial markets, only water SRC was significantly correlated to amylose content (r = –0.982, P < 0.001) among of four SRC tests. This suggests that, unlike udon noodle quality, high‐amylose content is indispensable in improving soft wheat baking quality, a process requiring less water retention capacity.