Assessing vulnerability of New Zealand lakes to loss of conservation value from invasive fish impacts

1. Predictions of invasion risk for seven non‐indigenous fish species, ecological impact scores for individual species, and lake conservation rankings were linked to develop Invasion Risk Impact (IRI) and Lake Vulnerability (LV) indices that help identify New Zealand lakes most at risk of loss of conservation value from potential multi‐species invasions.
2. Species‐specific IRI scores (the product of predicted invasion risk and species impact) highlighted Eurasian perch (Perca fluviatilis) and the brown bullhead (Ameiurus nebulosus), as the species most likely to spread and cause ecological harm in lakes. For 3431 lakes >1 ha throughout New Zealand, total IRI tended to be highest for lowland riverine and dune lakes most of which are already colonized by multiple invasive fish species.
3. The LV index indicated that lakes most at risk of loss of conservation value from invasive fish impacts were predominantly (i) in the northern half of the North Island where several uncommon lake types occur, and (ii) along the west coast of the South Island where conservation value is often greater, largely because of low catchment modification.
4. The IRI and LV indices can be used to assist with setting priorities for surveillance monitoring, advocacy, and response planning targeted at preventing the establishment of invasive fish in moderate‐to‐high value lakes most susceptible to ecological impacts. Both indices can be adapted to accommodate alternative impact and conservation scoring systems, providing a flexible tool for local‐ and national‐scale assessments of lake vulnerability to fish invasion impacts.

Copyright © 2016 John Wiley & Sons, Ltd.     

Replication of neurovirulent equine herpesvirus type 1 (EHV-1) in CD172a+ monocytic cells

Equine herpesvirus type 1 (EHV-1) is responsible for respiratory disorders, abortion and myeloencephalopathy (EHM) in horses. Two pathotypes of EHV-1 strains are circulating in the field: neurovirulent (N) and non-neurovirulent (NN). For both strains, CD172a⁺ monocytic cells are one of the main carrier cells of EHV-1 during primary infection, allowing the virus to invade the horse’s body. Recently, we showed that EHV-1 NN strains showed a restricted and delayed replication in CD172a⁺ cells. Here we characterize the in vitro replication kinetics of two EHV-1 N strains in CD172a⁺ cells and investigate if the replication of these strains is similarly silenced as shown for EHV-1 NN strains. We found that EHV-1 N replication was restricted to 7–8% in CD172a⁺ cells compared to 100% in control RK-13 cells. EHV-1 N replication was not delayed in CD172a⁺ cells but virus production was significant lower (10^3.0 TCID₅₀/10⁵ inoculated cells) than in RK-13 cells (10^8.5 TCID₅₀/10⁵ inoculated cells). Approximately 0.04% of CD172a⁺ cells produced and transmitted infectious EHV-1 to neighbour cells compared to 65% of RK-13 cells. Unlike what we observed for the NN strain, pretreatment of CD172a⁺ cells with histone deacetylases inhibitors (HDACi) did not influence the replication of EHV-1 N strains in these cells. Overall, these results show that the EHV-1 replication of N strains in CD172a⁺ cells differs from that observed for NN strains, which may contribute to their different pathogeneses in vivo.     

Responses of glutamine synthetase activity and gene expression to nitrogen levels in winter wheat cultivars with different grain protein content

Glutamine synthetase (GS) plays a central role in plant nitrogen (N) metabolism, which improves crops grain protein content. A pot experiment in field condition was carried out to evaluate GS expression and activity, and grain protein content in high (Wanmai16) and low grain protein (Loumai24) wheat cultivars under two N levels (0.05 and 0.15 g N kg⁻¹ soil). High nitrogen (HN) resulted in significant increases in GS1 and GS2 expression at 10 days after anthesis (DAA), and higher GS activity during the entire grain filling stage. HN also significantly increased yield, grain protein content and protein fraction (except for glutenin of Luomai24) in two wheat cultivars, which indicated that it increased grain yield and protein content by improving nitrogen metabolism. Wanmai16 showed higher grain protein content, gliadin and glutenin content, and had higher expression level of GS2 both in flag leaves and grains at early grain filling stage. However, Luomai24 had greater yield and higher expression level of GS1. The difference expression of GS2 and GS1 genes indicates they had various contributions to the accumulation of protein and starch in wheat grains, respectively. The results suggest that GS2 would be serving as a potential breeding target for improving wheat quality.     

秋冬萝卜新品种晋萝卜4 号的选育

晋萝卜4 号是以雄性不育系4-01A 为母本，自交系03-37-1 为父本配制而成的秋冬萝卜一代杂种，生育期80 d（天）。地上部叶丛半直立，叶片稀疏，肉质根圆柱形，表皮光滑，出土部分皮绿色，入土部分皮白色，近1/2 露出地面。含水量适中，肉质甜脆，商品性好。肉质根纵径30 cm，横径7～8 cm，单根质量1.5 kg，每667 m² 产量5 000 kg 左右。适宜山西省及其周边地区种植。     

春白萝卜新品种雪单3 号的选育

雪单3 号是利用双单倍体育种技术选育的春白萝卜新品种。母本ED0108A 是以梅花春萝卜× 白玉春萝卜进行花药培
养获得的DH 系为轮回父本，与不育系进行多次回交，转育成的雄性不育系。父本ED3128 是由迟花春萝卜× 天鸿春萝卜进行
花药培养获得的DH 系。该品种生育期60 d（天），植株开展度45 cm，裂叶，小叶11 对，叶片数20，叶簇平展，叶色深绿；
肉质根长圆柱形，白皮白肉，根长36 cm，横径7.1 cm，单根质量1.1 kg，高抗黑腐病、芜菁花叶病毒病、黄瓜花叶病毒病和花
椰菜花叶病毒病，抗霜霉病，群体整齐度高。每667 m² 产量4 000～5 000 kg。适宜在湖北、湖南、河南、山东等地区早春栽培。     

茄子新品种海丰长茄1 号的选育

海丰长茄1 号是以双单倍体（DH）株系02-QP-19 为母本，优良自交系A-40 为父本配制而成的长茄一代杂种。平
均始花节位为第9 节，植株生长势强，叶片绿色，叶脉、叶柄和主茎的颜色为紫色，植株半开张类型。果实平均纵径31.5
cm，横径4.5 cm，果皮紫黑色，有光泽，果实顶部尖，平均单果质量220 g，VC 和VP 的含量分别为23.2 mg·kg^-1 和0.035%。
一般每667 m² 产量5 000 kg 左右。适宜北京、吉林和黑龙江等地区露地种植。     

浅议慕课及其对精品课程建设的启示

慕课(MOOC)在学习成本低、学习效率高、交互性强等方面受到了广大学习者的青睐,逐渐成为终身学习的一种渠道。精品课程建设是高校教育与教学改革工程必不可少的环节,精品课程建设第二期工程——精品资源共享课正在建设过程中。慕课运行方式对我国精品资源共享课建设具有一定借鉴意义。     

Polymerisation of gluten proteins in developing wheat grain as affected by desiccation

The breadmaking quality of wheat is affected by the composition of gluten proteins and the polymerisation of subunits that are synthesised and accumulated in developing wheat grain. The biological mechanisms and time course of these events during grain development are documented, but not widely confirmed. Therefore, the aim of this study was to monitor the accumulation of gluten protein subunits and the size distribution of protein aggregates during grain development. The effect of desiccation on the polymerisation of gluten proteins and the functional properties of gluten were also studied. The results showed that the size of glutenin polymers remained consistently low until yellow ripeness (YR), while it increased during grain desiccation after YR. Hence, this polymerisation process was presumed to be initiated by desiccation. A similar polymerisation event was also observed when premature grains were dried artificially. The composition of gluten proteins, the ratios of glutenin to gliadin and high molecular weight-glutenin subunits to low molecular weight-glutenin subunits, in premature grain after artificial desiccation showed close association with the size of glutenin polymers in artificially dried grain. Functional properties of gluten in these samples were also associated with polymer size after artificial desiccation.     

Disulphide structure of high-molecular-weight (HMW-) gliadins as affected by terminators

This study aimed at elucidating SS-bonds of HMW-gliadins (HGL) from wheat with the focus on terminators of glutenin polymerisation. HGL from wheat flour extracts non-treated or treated with the S-alkylation reagent N-ethylmaleinimide (NEMI) were compared. HGL from wheat flour Akteur were isolated, hydrolysed with thermolysin and the resulting peptides pre-separated by gel permeation chromatography and analysed by liquid chromatography/mass-spectrometry using alternating electron transfer dissociation/collision-induced dissociation. Altogether, 22 and 28 SS-peptides from samples without and with NEMI treatment, respectively, were identified. Twenty-six peptides included standard SS-bonds of α- and γ-gliadins, high-molecular-weight and low-molecular-weight glutenin subunits. Eleven SS-bonds were identified for the first time. Fifteen peptides unique to HGL contained cysteine residues from gliadins with an odd number of cysteines (ω5-, α- and γ-gliadins). Thus, gliadins with an odd number of cysteines, glutathione and cysteine had acted as terminators of glutenin polymerisation. Decisive differences between samples without and with NEMI treatment were not obvious showing that the termination of polymerisation was already completed in the flour. The two HGL samples, however, were different in the majority of ten peptides that included disulphide-linked low-molecular-weight (LMW) thiols such as glutathione and cysteine with the former being enriched in the non-treated HGL-sample.     

A new lean no time test baking method with improved discriminating power

In response to customer concerns related to gluten strength in commercial baking, the Canadian Grain Commission assessed whether the Canadian Short Process (CSP) test bake method was generating useful data related to intrinsic strength of wheat varieties. Assessment of CSP loaf volume data for Canadian variety trials spanning 2003 to 2013 showed very little correlation with dough strength parameters as measured by farinograph and extensigraph. A lean no time (LNT) test baking method was developed that can better discriminate genotypes and provide objective indicators of the effect of intrinsic dough strength on baking quality. From early method development, through method validation and verification using diverse sets of samples targeting different Canadian wheat classes and grown in three different crop years, results showed the LNT method to be more discriminating and easily adopted by other laboratories. In 2015, the LNT method was adopted as the method of choice in future Canadian variety registration trials. The LNT method is fast, simple and well-suited to high throughput test baking conditions encountered in the evaluation of large numbers of breeder lines. A new objective parameter, loaf top ratio, was also introduced and found to correlate well with dough strength and dough handling properties.