Effects of maturity genes E2 and E3 on yield formation in soybean cultivar Enrei in warm region,Fukuyama in Japan

ABSTRACT

Understanding how maturity genes affect soybean yield formation will provide important information for crop management decisions. This study aimed to reveal how maturity genes E2 and E3 in the soybean cultivar ‘Enrei’ affect yields and yield formation in warm regions of Japan. ‘Enrei’ (e2e3) and three near-isogenic lines of ‘Enrei’ (e2E3, E2e3, and E2E3) were cultivated in 2016 and 2017 in Fukuyama, Japan (34°30′N, 133°23′E). Two sowing dates were set in each year (June sowing and July sowing). E2 extended the period from emergence to R1 and also the period from R1 to R7, whereas E3 extended only the period from emergence to R1. Interaction between E2 and E3 did not affect duration of the period from emergence to R1, but did affect the period from R1 to R7. Although seed yield did not differ between genotypes in the June sowings, the effects of E2 and E3 on seed yield in July sowing were both significant and interaction between E2 and E3 also observed. The total number of nodes increased in E3 genotypes in both sowing dates, especially in E2E3. Pod-set ratio was lower in E2 and E3 genotypes than in e2 and e3 genotypes in the June sowings, but did not differ between genotypes in the July sowings. The high yield of E2E3 genotypes in the July sowings was attributed to increased number of nodes and flower production while maintaining pod-set ratio. Appropriate choice of sowing date is suggested to be essential when using E3 genotypes.Abbreviations: HI: harvest index; NIL: near-isogenic line; RUE: radiation use efficiency; TDM: total above-ground dry matter; TRI: total solar radiation intercepted     

A set of near-isogenic lines for blast resistance genes with an Indica-type rainfed lowland elite rice (Oryza sativa L.) genetic background

A set of near-isogenic lines for blast resistance genes was developed by using an Indica-type elite rice variety, IR49830-7-1-2-2, suitable for the rainfed lowland conditions in the tropics, as a genetic background. Initially, we revealed that IR49830-7-1-2-2 harbors five blast resistance genes - Pia, Pib, Pik-s, Pita, and Pi11(t) - by using a differential system involving 19 selected standard blast isolates from the Philippines. Based on this result, we developed nine near-isogenic lines (NILs) targeting eight resistance genes - Pik, Pi7(t), Pi3, Pi5, Pita-2, Piz-5, Pish, and Pi9 - by recurrent backcrossing. The introgression of each resistance gene in the NILs was confirmed by reaction patterns to the blast isolates, allelism tests, and DNA marker analysis. In addition, a genome-wide DNA marker survey revealed that most of the chromosome regions in each NIL were of the IR49830-7-1-2-2 type. The agricultural characteristics of most of the developed NILs were almost the same as those of IR49830-7-1-2-2. Moreover, with one exception, they showed submergence tolerance similar to IR49830-7-1-2-2. The developed NILs could be used as a multiline variety suitable for the rainfed lowland in the tropics.     

Isolation and characterization of staphylococci from external auditory meatus of dogs with or without otitis externa with special reference to Staphylococcus schleiferi subsp. coagulans isolates

Staphylococci were isolated from the external auditory meatus in 14 (48.3%) of 29 dogs affected with otitis externa (OE dogs) and 28 (68.3%) of 41 dogs without OE (non-OE dogs). Twenty-two OE isolates were identified as belonging to 12 species, and 42 non-OE isolates were identified as belonging to 13 species. The predominant species found in both OE and non-OE isolates were S. intermedius, and S. epidermidis. Thirty-eight (59.4%) of 64 isolates were resistant to one or more of the 17 antimicrobial agents tested. Resistance to PCG and ABPC was most frequent. S. schleiferi subsp. coagulans, a recent etiologic agent of canine OE, was isolated from OE and non-OE dogs. All of the 5 S. schleiferi subsp. coagulans isolates showed typical characteristics. No clear difference in the extracellular enzyme or toxin profiles, nor in the PFGE patterns, was demonstrated between the OE and non-OE isolates of S. schleiferi subsp. coagulans. A new PCR primer set specific for 16S rDNA was designed to identify strains of S. schleiferi subsp. coagulans. The amplified fragment was detected in all of the 5 isolates as well as the type strain GA 211 (=JCM 7470) and a reference strain GA 11, but was not detected in any strains of the related species, S. aureus, S. intermedius and S. hyicus. The PCR may allow a simple, rapid and precise identification of S. schleiferi subsp. coagulans, in addition to the standard tube test for free coagulase.     

Infusion of guaifenesin,ketamine, and medetomidine in combination with inhalation of sevoflurane versus inhalation of sevoflurane alone for anesthesia of horses

OBJECTIVE: To evaluate effects of infusion of guaifenesin, ketamine, and medetomidine in combination with inhalation of sevoflurane versus inhalation of sevoflurane alone for anesthesia of horses. DESIGN: Randomized clinical trial. ANIMALS: 40 horses. PROCEDURE: Horses were premedicated with xylazine and anesthetized with diazepam and ketamine. Anesthesia was maintained by infusion of guaifenesin, ketamine, and medetomidine and inhalation of sevoflurane (20 horses) or by inhalation of sevoflurane (20 horses). A surgical plane of anesthesia was maintained by controlling the inhaled concentration of sevoflurane. Sodium pentothal was administered as necessary to prevent movement in response to surgical stimulation. Hypotension was treated with dobutamine; hypoxemia and hypercarbia were treated with intermittent positive-pressure ventilation. The quality of anesthetic induction, maintenance, and recovery and the quality of the transition to inhalation anesthesia were scored. RESULTS: The delivered concentration of sevoflurane (ie, the vaporizer dial setting) was significantly lower and the quality of transition to inhalation anesthesia and of anesthetic maintenance were significantly better in horses that received the guaifenesin-ketamine-medetomidine infusion than in horses that did not. Five horses, all of which received sevoflurane alone, required administration of pentothal. Recovery time and quality of recovery were not significantly different between groups, but horses that received the guaifenesin-ketamine-medetomidine infusion required fewer attempts to stand. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that in horses, the combination of a guaifenesin-ketamine-medetomidine infusion and inhalation of sevoflurane resulted in better transition and maintenance phases while improving cardiovascular function and reducing the number of attempts needed to stand after the completion of anesthesia, compared with inhalation of sevoflurane.     

Light-use properties in two sun-adapted shrubs with contrasting canopy structures

We investigated the impact of high solar irradiance and elevated temperature on carbon gain by two, co-occurring, sun-adapted, dwarf shrub species, Planchonella obovata var. dubia (Koidz.) Hatusima and Hibiscus glaber Matsumura, growing on sun-exposed ridges in the Bonin Islands, in the subtropical Pacific Ocean. Planchonella had steeply inclined, longer lived, sclerophyllous leaves, whereas Hibiscus has thinner, more horizontally oriented, and shorter lived leaves. We tested the hypothesis that leaf physiological tolerance to high light is lower in Planchonella than in Hibiscus. Under relatively high irradiances (photosynthetic photon flux density, PPFD, > 500 micromol m(-2) s(-1)), net photosynthetic rate (P(n)) was about 8.0 and 0.4 micromol m(-2) s(-1) in mature and young leaves of Planchonella, and about 12.4 and 10.3 micromol m(-2) s(-1) in mature and young leaves of Hibiscus, respectively. Both P(n) and photosystem II (PSII) quantum yield at a given PPFD were lower in Planchonella than in Hibiscus, whereas non-photochemical quenching (NPQ) at a given PPFD was higher in Planchonella. When leaf discs were exposed to high light (1900 micromol m(-2) s(-1) PPFD) at 37, 40 or 43 degrees C for 3 h, the recovery of PSII quantum yield (F(v)/F(m)) in the following 60-min dark period was slower in Planchonella than in Hibiscus, indicating that the ability of PSII to tolerate high light and high temperature was less in Planchonella than in Hibiscus. We postulate that there is a linkage between leaf display and leaf photochemical ability in sun-adapted shrub species.     

Pharmacokinetics of procaterol in thoroughbred horses

Procaterol (PCR) is a beta‐2‐adrenergic bronchodilator widely used in Japanese racehorses for treating lower respiratory disease. The pharmacokinetics of PCR following single intravenous (0.5 μg/kg) and oral (2.0 μg/kg) administrations were investigated in six thoroughbred horses. Plasma and urine concentrations of PCR were measured using liquid chromatography–mass spectrometry. Plasma PCR concentration following intravenous administration showed a biphasic elimination pattern. The systemic clearance was 0.47 ± 0.16 L/h/kg, the steady‐state volume of the distribution was 1.21 ± 0.23 L/kg, and the elimination half‐life was 2.85 ± 1.35 h. Heart rate rapidly increased after intravenous administration and gradually decreased thereafter. A strong correlation between heart rate and plasma concentration of PCR was observed. Plasma concentrations of PCR after oral administration were not quantifiable in all horses. Urine concentrations of PCR following intravenous and oral administrations were quantified in all horses until 32 h after administration. Urine PCR concentrations were not significantly different on and after 24 h between intravenous and oral administrations. These results suggest that the bioavailability of orally administrated PCR in horses is very poor, and the drug was eliminated from the body slowly based on urinary concentrations. This report is the first study to demonstrate the pharmacokinetic character of PCR in thoroughbred horses.     

Bottom feeding and net chasing improve foraging behavior in hatchery-reared Japanese flounder Paralichthys olivaceus juveniles for stocking

We examined the effect of bottom feeding and net chasing as means to improve the maladaptive off-bottom swimming of hatchery-reared Japanese flounder Paralichthys olivaceus juveniles for stock enhancement. Three treatments were tested: (1) a bottom feeding treatment in which fish were fed near the bottom; (2) a net chasing treatment in which fish were chased by a hand net two to four times a day, and (3) a surface feeding treatment in which fish were fed from the surface (control treatment). Foraging behavior at the surface with surface feeding was analyzed 1 day before initiating these treatments and 2 weeks thereafter. A comparison of the pre- and post-treatments revealed that off-bottom swimming was less in the bottom feeding treatment and net chasing treatments. A comparison of off-bottom swimming in the bottom feeding treatment between the pre- and post treatments revealed that bottom fed fish showed less off-bottom swimming than surface fed fish. These findings suggest that fish behavior can be manipulated during the rearing period and that such manipulations can be used to improve the behavior of fish for release.     

Concentration of cephalothin in body fluids and tissue samples of Thoroughbred horses

Cephalothin (CET) concentrations in body fluids (plasma, synovial fluid, pleural fluid, peritoneal fluid, and aqueous humor) and tissue samples (bone, lung, jejunum, hoof, and subcutaneous tissue) were investigated to consider the treatment of infectious diseases in horses. CET 22 mg/kg body weight was intravenously administered to 12 horses. Samples were collected from four different horses at 1, 3, and 5 hr after administration. The CET concentration in body fluids other than aqueous humor was maintained above the MIC₉₀ values of Streptococcus zooepidemicus and Staphylococcus aureus until 5 hr, but it was not maintained above that of S. aureus in bone. CET (22 mg/kg twice a day) is effective for septic arthritis, pleuritis, and peritonitis caused by gram-positive bacteria but ineffective for osteomyelitis.     

Distinct regional profiles of trace element content in muscle of Japanese eel Anguilla japonica from Japan, Taiwan, and China

Trace element distribution patterns were examined in Japanese eel from five Asian regions for the purpose of identifying the elements and patterns that could be used to determine provenance. Distinctive patterns were found in eels from the Japanese prefectures of Miyazaki, Kagawa, and Shizuoka, and from Taiwan and China. The levels of six trace elements, selenium, mercury, copper, manganese, zinc, and arsenic, in muscle tissue varied among eels of different origins, and factorial analysis of the elemental patterns showed that Factor 1 was attributable to selenium and mercury levels and Factor 2 to zinc and copper levels. Multivariate analysis showed that the patterns of elemental composition in fish muscle were mainly differentiated by these two factors.