New insights into genotypic thermodependency of cytoplasmic male sterility for hybrid barley breeding

The cytoplasmic male sterility (CMS) system msm1 in barley is known to be thermosensitive, sometimes resulting in spontaneous fertility restoration in the absence of the corresponding restorer gene Rfm1. Here, we investigated genotypic differences concerning temperature sensitivity and the plant developmental stage at which elevated temperature induces spontaneous fertility restoration in three CMS mother lines. While one line stayed completely male sterile, a significantly higher fertility was observed in two lines after treatment from growth stage DC 41 until maturation. Microscopic analysis revealed that sterile anthers contained neither intact pollen, nor remains of aborted pollen grains, whereas pollen was visible in anthers of potentially fertile plants. We conclude that the barley CMS system affects anther and pollen development prior to meiosis. Elevated temperature during heading and flowering can lead to a spontaneous fertility restoration by reactivating pollen growth. Nevertheless, genotypic variation exists enabling the selection for stable CMS mother lines and the development of F₁ hybrids with high hybridity. As spontaneous fertility restoration due to environmental effects is difficult to phenotype, further investigations will focus on the development of molecular markers for marker‐assisted selection.     

A draft sequence of the rice genome (Oryza sativa L. ssp. japonica)

The genome of the japonica subspecies of rice, an important cereal and model monocot, was sequenced and assembled by whole-genome shotgun sequencing. The assembled sequence covers 93% of the 420-megabase genome. Gene predictions on the assembled sequence suggest that the genome contains 32,000 to 50,000 genes. Homologs of 98% of the known maize, wheat, and barley proteins are found in rice. Synteny and gene homology between rice and the other cereal genomes are extensive, whereas synteny with Arabidopsis is limited. Assignment of candidate rice orthologs to Arabidopsis genes is possible in many cases. The rice genome sequence provides a foundation for the improvement of cereals, our most important crops.     

Disseminated Mycobacterium avium subsp. hominissuis infection and ascites in an FIV-positive cat

A domestic shorthair cat was presented to the Veterinary Teaching Hospital at The University of the West Indies with a history of anorexia, ataxia, and lethargy. On physical examination, moderate abdominal distension and a palpable abdominal fluid wave were noted. Dark yellow, cloudy fluid was collected via abdominocentesis. Fluid analysis indicated that the effusion was a transudate containing low numbers of macrophages and occasional neutrophils. Some of the macrophages contained rod-shaped nonstaining structures of variable length (2-4 um). These structures were also seen extracellularly in low numbers. The morphology of the structures was suggestive of Mycobacterium. The cat's condition continued to deteriorate, and it died within a few hours of being admitted. Further diagnostic tests revealed feline immunodeficiency virus (FIV) infection with concurrent Mycobacterium avium subsp hominissuis infection. To the authors’ knowledge, this is the first reported case of nontubercular mycobacterial-related ascites in a cat.     

New NIRS calibrations for fiber fractions reveal broad genetic variation in Brassica napus seed quality

Near-infrared reflectance spectroscopy (NIRS) calibrations were developed for the estimation of neutral detergent fiber (NDF), acid detergent fiber (ADF), and acid detergent lignin (ADL) in intact seeds of oilseed rape ( Brassica napus ). A set of 338 diverse winter oilseed rape genotypes showing broad variation for seed color was used as a basis for the new calibrations. Different calibrations were generated for 10 or 1 mL seed volumes, respectively. In both seed volumes good coefficients of determination for external validation (R(2)) of the calibrations were obtained for ADL, the major antinutritional fiber fraction in oilseed rape meal, and adequate calibrations for NDF and ADF. Evaluation of diverse B. napus germplasm with the new calibrations revealed a surprisingly broad variation in contents of ADL in dark-seeded oilseed rape. The ability to use NIRS for efficient selection of low-fiber genotypes, irrespective of seed color, represents an important breakthrough in breeding for improved nutritional quality of seed extraction meals from oilseed rape.     

提取温度对茶汤冷后浑和雾霾度的影响(英文)

茶汤冷后浑的形成和雾霾度随提取温度提高而增加,茶叶中参与冷后浑形成的成分开始大量溶出茶汤的温度在50～60℃之间.与50℃及其以下温度提取的茶汤相比,在60℃及其以上温度提取获得的茶汤形成的冷后浑粒子体积密度高,粒子粒径小而且更均匀一致.HPLC分析结果证实,酯型茶黄素类是参与茶汤冷后浑的一类重要成分,咖啡碱对茶汤冷后浑和雾霾度的影响取决于茶黄素类,尤其是酯型茶黄素的多少.作者指出,采用两段提取法可以分别满足冰茶用速溶茶和普通速溶茶生产的需要.     

Serum biochemical reference intervals for wild dwarf ornate wobbegong sharks (Orectolobus ornatus)

Background: Sharks are important to sport and commercial fishing, public aquaria, and research institutions. However, serum biochemical reference values have been established for few species. Objective: The aim of this study was to establish serum biochemical reference intervals for wild‐caught dwarf ornate wobbegong sharks (Orectolobus ornatus). Methods: Fifty wobbegongs were caught, and their health status, sex, length, and weight were evaluated and recorded. Following collection of blood, serum biochemical analytes were measured and analyzed using standard analytical and statistical methods. Combined samples generated means, medians, and reference intervals. Results: For the measured analytes, means (reference intervals) were as follows: sodium 287 (284–289) mmol/L, chloride 277 (274–280) mmol/L, potassium 5.2 (5.0–5.3) mmol/L, total calcium 4.6 (4.5–4.7) mmol/L, magnesium 1.9 (1.7–2.0) mmol/L, inorganic phosphate 1.8 (1.7–1.9) mmol/L, glucose 2.6 (2.4–2.8) mmol/L, total protein 46 (45–47) g/L, urea 396 (392–401) mmol/L, creatinine ≤0.02 mmol/L, total bilirubin 2.0 (1.9–2.1) μmol/L, cholesterol 1.3 (1.2–1.4) mmol/L, triglyceride 0.5 (0.4–0.6) mmol/L, alkaline phosphatase 24 (21–28) U/L, alanine aminotransferase 3 U/L, aspartate aminotransferase 28 (25–31) U/L, creatine kinase 49 (38–59) U/L, and osmolarity 1104 (1094–1114) mmol/L. Serum values were not affected by sex, length, or weight. Conclusions: Established reference values will assist with clinical evaluation and treatment of dwarf ornate wobbegongs in aquaria, research institutions, and the wild.     

pH对红茶冷后浑粒子形成和固形物提取率的影响

ｐＨ对茶叶固形物提取率的影响在提高速溶茶产量中有重要意义，在ｐＨ１．２时提取，茶叶固形物产量比用正常ｐＨ的沸蒸馏水提取时高１倍，Ｈ￣＋通过提高茶汤的固形物浓度、促进茶多酚与茶汤中的多糖或蛋白质分子的亲核基反应而增加红茶冷后浑粒子的形成。ＨＰＬＣ结果揭示，茶黄素类和茶叶儿茶素类是影响红茶冷后浑粒子形成和汤色的重要物质。在碱性条件下，茶黄素类和某些儿茶素类，如ＥＧＣＧ，ＥＣＧ和ＧＣ产生离解或降解，以致冷后浑粒子趋于溶解，茶汤色泽变黑，文中对控制温度和ｐＨ生产冰茶用速溶茶和普通速溶茶的分步提取法也提出了讨论。     

Evaluation of cytochalasin B (CB) treatments for triploidy induction in the blacklip abalone, Haliotis rubra (Leach, 1814)

The effectiveness of cytochalasin B (CB) treatments for inducing triploidy was evaluated in the blacklip abalone Haliotis rubra (Leach, 1814) in two orthogonal design experiments. The first experiment employed three dosages (DSs) of 0.25, 0.5 and 1.0 mg CB L^?1, three starting times (STs) of 5, 15 and25 min post fertilization and three treatment durations (TDs) of 10, 20 and 40 min, for a total of 27 treatments. The second experiment comprised of two DSs of 0.25 and 0.5 mg CB L^?1, five STs of 5, 15, 20, 25and 30 min post fertilization, and three TDs of 10, 20 and 40 min, for a total of 30 treatments. Water temperature was held at 17.5–18.5°C. Day 3 larvae were sampled for triploidy using flow cytometry (FCM) and survival. Optimal inductions were treatments starting at 15 or 20 min post fertilization and continuing for 40 min, and those initiated 25 or 30 min post fertilization for 20 or 40 min, using 0.5 mg CB L^?1. These treatments were all targeted at inhibition of the second polar body (PB2) formation and yielded triploidy rates of 84.8–89.5% coupled with (relative) survival rates of 20.1–52.1% in the first experiment, and corresponding rates of 86.5–96.5% and 33.0–74.1%, respectively, in the second experiment. A common and essential feature of these optimal conditions is that treatment must fully span the period of time for most of the eggs to extrude PB2. Treatments that resulted in suppression of the first polar body (PB1) formation induced triploidy levels below 71.5% and 57.6% in experiments 1 and 2 respectively. Treatments that had overlapping effects on both PB1 and PB2 extrusion led to triploidy rates above 80% but very low survival rates of 1.8% and 5.4% in experiments 1 and 2 respectively.