朱砂根和红凉伞花器官的形态补充描述

朱砂根和红凉伞在最新的分类系统中均隶属于报春花科（Primulaceae）紫金牛属（Ardisia）植物,由于二者在植株形态上存在过渡性状,从而缺乏明显的区分界限,而花部形态是属下划分及种间界定的关键性状,具有较高的分类价值,因此,基于对二者原始形态描述的基础上,分别对其花器官形态与解剖结构进行补充,旨在更加准确地掌握它们在形态性状上的差异。结果表明：朱砂根和红凉伞均为圆齿亚属,主要区别在于叶色的过渡,其余形态无太大的差异性,黑色腺点分布于2种植株的所有器官中,具有较高的观赏价值;朱砂根和红凉伞的花序较多,从外到内不断分化,而花序梗随着花芽的分化逐渐伸长;通过石蜡切片解剖发现,朱砂根和红凉伞花芽分化较早,最小采样花序大小为0.5 mm左右,2种植株均处于花芽分化末期,因此,从外观上不能反映其内部的结构变化;朱砂根的子房膨大有2种类型,当横径>纵径时,子房分化为2室,胚珠和花粉粒成熟,易于受精;纵径>横径时,柱头快速突破花冠裂片高于雄蕊,但子房暂未分室,未见花药明显散粉,导致受精失败和柱头脱落;而红凉伞子房横径和纵径同时生长易于受精,座果率略高于朱砂根。此外,二者通常形成2室子房,本研究还发现朱砂根中具有分化为3室的子房,而红凉伞子房则分隔为完整的4室,后期花器官在外部形态发育过程中没有明显的区别,且二者的花芽分化、开花和坐果等物候期持续时间一致,但朱砂根花芽分化早于红凉伞约7~10 d,这可能与所处的生境不同有关,结果可为物种鉴定及属内分类修订提供参考依据。     

生长素相关基因在茶树腋芽冬季休眠不同生长阶段的表达分析

利用实时定量PCR技术研究了从本实验室构建的茶树休眠芽与萌动芽抑制消减杂交文库中分离出来的与生长素相关的基因片段在茶树腋芽冬季休眠不同阶段的表达模式。研究结果表明：（1）与生长素响应因子同源的6条EST片段中,有5条的表达量休眠期高于萌发期,另外1条则相反。（2）与生长素原初反应基因同源的3条EST片段的表达模式存在差异,其中与SAURs同源的EST在休眠阶段上调表达,休眠解除以后下调表达。而与GH3和Aux/IAAs同源的2条EST在萌发阶段有一个表达高峰,而在休眠期和萌发以后,表达量都下降。（3）与生长素结合类蛋白同源的茶树CsGLP1表达量在萌发期高于休眠期。（4）与生长素内向运输载体基因同源的EST片段在深休眠期的表达量最高。（5）2条受生长素调控的EST表现出不同的表达模式,生长素诱导表达的EST在休眠期的表达量高于萌发期及随后阶段,而另外1条受生长素抑制的EST片段在萌发期的表达远远高于休眠期。这些结果初步说明生长素促进茶树腋芽的冬季休眠。     

甘蔗花芽分化及花序发育过程的石蜡切片显微观察与分析

常规杂交是甘蔗遗传改良的主要手段,开花诱导是亲本杂交的关键。花芽分化和花序发育对甘蔗开花至关重要,但目前笔者们对这一过程还缺少必要的了解。本研究以当前甘蔗主栽品种粤糖93-159为材料,对其茎尖分生区花芽分化及花序发育过程进行石蜡切片显微观察。结果显示,甘蔗开花过程可明显划分为6个阶段:营养生长阶段——甘蔗分生区维持营养生长;花芽分化阶段——生长锥分生区膨大,产生花序分生组织;枝梗分化阶段——分生区周围的褶皱分化产生一次、二次枝梗分生组织;小穗/小花原基分化阶段——沿枝梗产生的小穗分生组织分化出2朵小花分生组织;花器官分化阶段——小花分生组织分化形成典型花器官;成熟阶段——抽穗开花,可以授粉。此结果揭示了甘蔗花发育分化过程中的组织形态变化,可为甘蔗开花机理的深入研究提供参考。      

The use of surfactants to enhance acaricide control of Phytonemus pallidus (Acari: Tarsonemidae) in strawberry

The tarsonemid mite, Phytonemus (Tarsonemus) pallidus ssp. fragariae (Zimmerman), is a serious pest of strawberry throughout much of Europe and North America. Many of the plant protection products previously effective against the mite, which causes stunting and distorting of leaves and buds, reducing fruit yield and quality, are no longer available. Finding alternative acaricides for control is a priority. In two field trials, we tested 9 foliar applied plant protection products to determine the efficacy for control of Phytonemus pallidus, and to assess their effects on natural enemies. The products tested as foliar applications (dose ha⁻¹) were; abamectin 18 g/l EC (250, 500, 750, 1250 ml), tebufenpyrad 20% WP (500 g), fenpyroximate 51.3 g/l SC (1.0 l), bifenazate > 90% WP (400 ml), spiromesifen 24 g/l SC (500 ml), acequinocyl 15.8% SC (1.0 l), spirodiclofen 240 g/l SC (400 ml), etoxazole 110 g/l SC, and the surfactant, Silwett L-77 (Heptamethyltrisiloxane 0.05% (50 ml)). Effective products were used in admixture with the surfactant to investigate potential increased efficiency against P. pallidus. In each experiment, two applications were applied to plants previously inoculated with P. pallidus.     

Herbivory tolerance of cotton expressing insecticidal proteins from Bacillus thuringiensis: responses to damage caused by Helicoverpa spp. and to manual bud removal

Transgenic cotton varieties expressing Cry IA(c) insecticidal proteins from Bacillus thuringiensis (`Bt cotton') remain vulnerable to non-lepidopteran insects. In addition, they are susceptible to lepidopteran pests when the efficacy of Bt toxins falls because of ontogenetic and/or environmental factors. Hence the importance of knowing to what extent Bt cotton is able to tolerate damage. The degree of tolerance of Bt cotton to actual and simulated insect damage was assessed in three field experiments. Exp. 1 compared the effects of Helicoverpa spp. (Lepidoptera: Noctuidae) on the growth, development and yield of Bt cotton with those of its near isogenic non-Bt counterpart in two genetic backgrounds (Siokra V15, Sicala V2) under two regimes of chemical control of insects (S1: nine insecticide applications during the growing cycle, S2: six insecticide applications). Exp. 2 compared insecticide-protected Bt crops with crops manually damaged to simulate (a) early-season loss of vegetative buds, (b) loss of flowerbuds, and (c) loss of both vegetative and reproductive buds. Also using manual damage, Exp. 3 evaluated the effect of timing of flowerbud loss on the yield and maturity time of insecticide-protected Bt crops. In Exp. 1, well-protected Bt crops (S1) yielded 24% more than their less-protected counterparts (S2). The less protected crops had, however, substantially more immature fruit at the end of the season highlighting a considerable potential for recovery. Poor soil conditions, interacting with season length accounted for the difference between potential and actual compensation in crops that were exposed to almost continuous damage by Helicoverpa spp. Under more favourable growing conditions, maturity was delayed but yield of damaged Bt crops was unaffected by discrete episodes of simulated herbivory (Exps. 2 and 3). The introduction of B. thuringiensis genes into cotton does not seem to have reduced the considerable capacity of the crop to tolerate insect damage, and this attribute should be considered in the development of pest management strategies for Bt crops.     

芒果MiAGL80基因特征及表达模式分析

AGL80/FEM111属于Type I型MADS-box基因家族,调控拟南芥中央细胞及胚乳的发育。目前,AGL80在木本植物中鲜有研究报道。本研究从芒果转录组数据中获得并命名为MiAGL80基因。生物信息学分析表明：MiAGL80基因位于1号染色体上,ORF全长为897 bp,无内含子,编码299个氨基酸,理论等电点为4.95,蛋白质分子量为73.19 kDa,氨基酸序列中含有1个MADS_SRF_like保守结构域。系统进化树分析表明：芒果MiAGL80与阿月浑子PvAGL80最为接近,且同源性最高,氨基酸相似性为64.29%。启动子序列分析显示：芒果MiAGL80基因的启动子包含光响应元件、逆境响应元件、转录因子结合位点以及激素响应元件等,其中光响应元件相较其他元件数量较多,不仅包含光调节相关元件,还包含昼夜节律表达所必需的区域元件;激素响应元件中包括赤霉素响应元件、生长素响应元件和乙烯响应元件;逆境响应元件主要是干旱响应元件。基因表达模式分析显示：在芒果果实中,MiAGL80随着芒果果实的逐渐发育,其在果肉中的表达水平持续下降,在花后100 d的果实与成熟果中的表达水平很低;在种胚发育过程中其表达水平先上升后下降,在花后100 d的胚和成熟胚中表达水平也很低;在种胚萌发发育期,其表达水平再次升高。在成花发育不同时期的组织器官中：MiAGL80主要在叶片中表达,其表达量先降低后逐渐升高,然后再降低,在花器官发育末期达到最大值;在花芽中的表达水平也显著高于营养芽;但在茎中表达量极低,几乎不表达。说明MiAGL80在芒果果实发育、种胚发育、种子萌发以及成花调控方面发挥作用。以上研究结果为深入研究MiAGL80基因的功能提供参考。     

Characterization and Genetic Analysis of a Novel Mutant mst of Rice Defective in Flower Development

A spontaneous mutant with multiple stigmas (mst) was found in an indica rice line 466. The mst mutant exhibits normal at the vegetative development stage and produces normal inflorescence structures. The difference between the mutant and the wild type was observed when the stamen primordium began to develop. In the mst florets, palea and lemma opened, lodicules were homeotically transformed into palea/lemma-like structures, and stamens were homeotically transformed into carpel-like structures. It looked like multiple stigmas being full of the whole floret. The phenotypic changes of mst were very similar to that of B-like mutant spw1. Compared with other mutants with pistillate morphologies, the severe mst florets showed that the inner three floral organs were completely changed into palea/lemma-like structures. Moreover, the mutant was female sterile. Occasionally, with the changing environment, one or two stamens were fertile. Genetic analysis indicated that the mutant traits were controlled by a single recessive gene.     

Identification and characterization of Colletotrichum fructicola causing black spots on young fruits related to bitter rot of pear (Pyrus bretschneideri Rehd.) in China

In recent years, Pyrus bretschneideri Rehd. var. ‘Suli’ has been damaged by a disease characterized by the presence of black spots on young fruit in China, which was always followed by severe bitter rot on matured fruits. The etiology of these symptoms and their relationship with the bitter rot was unknown. A colony was routinely isolated from young and matured ‘Suli’ pear fruits showing black spots and rot symptoms, respectively. This fungal colony was identified as Colletotrichum fructicola based on morphological characteristics and DNA sequence data of 7 regions. C. fructicola was confirmed to be capable of eliciting both black spots and bitter rot symptoms by completion of Koch's Postulates. The results suggested that the disease characterized by the presence of black spots on young fruits is indeed an early stage of the bitter rot observed on matured fruits of ‘Suli’ pear. Variety resistance analysis indicated an obvious resistance variation possessed by the pear varieties generally cultured in China, with black spots only occurring on some pear varieties. Our results also indicated that wounding can break the quiescent infections, enhance the infectivity of C. fructicola, and lead to more rapid rot of young and matured fruits. These results provided a clear clue that C. fructicola can invade some varieties of P. bretschneideri Rehd. directly without entry via wounds, but subsequently turned into quiescent infection and causing black spots on the fruit surface. The quiescent infection acts as a pathogenic factor responsible for bitter rot of matured fruits. The influence of temperature and pH conditions for growth and colony morphology of C. fructicola were also evaluated. The characterization of C. fructicola causing bitter rot of pear (P. bretschneideri) is expected to provide useful information for controlling this economically important disease.     

芒果SEPALLATA3基因的生物信息学与表达分析

SEPALLATA3（SEP3）属于MADS-box基因家族,与植物的成花时间和花器官分化有关。在本研究中,从芒果转录组数据中挖掘获得了2个MiSEP3s基因,分别命名为MiSEP3-1和MiSEP3-2。生物信息学分析显示,MiSEP3-1和MiSEP3-2基因的基因组DNA长度分别为4189 bp和3721 bp,2个基因的开放阅读框长度一致均为732 bp,编码244个氨基酸,蛋白质分子量分别为59.29 kD和59.28 kD。2个MiSEP3s的氨基酸序列中含有典型的MADS结构域和K-box结构域。启动子序列分析显示,2个MiSEP3s基因启动子均包含光响应元件、激素响应元件、逆境响应元件和转录因子结合位点,但调控元件种类和数量存在差异。基因表达模式分析显示,2个MiSEP3s基因在营养期的茎、叶和芽中表达量较低,但在成花转变后期的芽中持续上调表达,在花中达到表达高峰。该结果为MiSEP3基因功能的研究提供参考。     

The effect of hail protection nets on Glomerella leaf spot in ‘royal Gala’ apple

In commercial apple orchards in southern Brazil, it is common to avoid hail damage by covering the trees with nets. This study was carried out to assess the effects of both black and white hail netting on the temporal dynamics of Glomerella Leaf Spot disease (GLS) in a commercial ‘Royal Gala’ apple orchard in a high-altitude region of southern Brazil during two growing seasons (2003/2004 and 2004/2005). Apple trees on M9 rootstock, trained to a slender spindle and with a spacing of 5.5 m × 3 m, were left uncovered (control) or covered with black or white hail netting. The incidence and severity of GLS were quantified biweekly from October to February by evaluating 100 leaves distributed randomly on four medium-height branches per plant on each 12 replications per treatment. Disease progress curves were constructed from the data and the epidemics were compared by using four epidemiological measures: the beginning of symptom appearance (BSA), the time to reach the maximum disease intensity (TRMDI), the maximum value of disease severity (Y_max), and the area under the disease progress curve (AUDPC). The highest intensity of GLS was observed in the plants under the black hail netting. Significant reductions in BSA and TRMDI and significant increases in Y_max and AUDPC were found among treatments in both growing seasons. However, no significant differences of GLS were found between the white hail netting and the control in either growing season.     

Planting time as a tactic to manage the small rice stink bug, Oebalus poecilus (Hemiptera, Pentatomidae), in Rio Grande do Sul, Brazil

Field studies throughout the year focused on the life history of the small rice stink bug, Oebalus poecilus, in southern Brazil. In addition, laboratory experiments examined the bug's life cycle and photoperiodic responses. Adults remain dormant during most of the year. Although activity is restricted to the period between November and March, four generations can develop in each rice-growing season, and populations can reach economically harmful levels. Late-planted rice, however, escapes attack because diapause is induced during early March. The results indicate that delaying and restricting the time of rice planting can be an effective pest management tactic in Rio Grande do Sul, because it results in asynchrony between the pest and the crop.     

广西育成大豆品种亲本分析

为提高优异品种选育效率，本研究对广西已育成的39个大豆品种系谱进行追溯，分析其亲本组配方式、地理来源及细胞核（质）遗传贡献，结果表明，育成的39个大豆品种（春大豆28个，夏大豆11个）来源于40个细胞核祖先亲本，17个细胞质祖先亲本；来源于广西本地、外省和国外祖先亲本的核（质）遗传贡献率分别为39.42 %（58.98%）、45.75 %（38.46%）和14.83 %（2.56%）；核祖先亲本主要来源于广西本地及生态条件相近的我国南方、巴西和美国。春大豆育成品种细胞质祖先亲本主要来源于广西、湖北和北京，夏大豆育成品种细胞质祖先亲本主要来源于广西、湖北和上海；2006年以来，96%的大豆育成品种是以育成品种和国外引种作为亲本组配而成；归纳出靖西早黄豆等8个核心春大豆祖先亲本，平果豆等5个夏大豆核心祖先亲本。广西大豆育成品种核遗传基础较为丰富，但还需加强新种质研究利用，以扩大品种的核质基础。        

Production and nutritional value of sorghum and black oat forages under nitrogen fertilization

The effect of nitrogen (N) fertilization on the dry‐matter (DM) yield and nutritional value of sorghum (Sorghum sp., cv. Jumbo) and black oat (Avena strigosa cv., IPR 61) was investigated in the context of forage and livestock production in southern Brazil. Sorghum was cultivated with 0, 37·5, 75, 150, 225, 300 and 375 kg N ha^?1 during the summer crop seasons of 2010/11 and 2011/12. Black oat received 0, 40, 80, 120, 160, 200 and 240 kg N ha^?1 in the winter of 2011. According to the adjusted polynomial regression, sorghum DM yield increased in response to N up to 288 (12·9 t ha^?1) and 264 kg ha^?1 (5·6 t ha^?1) in 2010/11 and 2011/12 respectively. Crude protein (CP) content of sorghum was highest at 349 and 328 kg N ha^?1, but in vitro dry‐matter digestibility (IVDMD) was highest at 212–207 kg N ha^?1 in 2010/11 and 2011/12 respectively. Sorghum neutral detergent fibre (NDF) and acid detergent fibre (ADF) were not affected by N fertilization. In black oat, the maximum DM yield (6·0 t ha^?1) was obtained with 187 kg N ha^?1; the IVDMD, NDF and ADF were not affected by N fertilization, but the CP content increased up to 220 kg N ha^?1. It is concluded that these forage species can improve the year‐to‐year amount and quality of forage produced but high rates of N fertilizer are required to achieve high yields. Fertilizer N rates of 210–280 kg N ha^?1 in sorghum and 180 kg N ha^?1 in black oat in the crop rotation provide the greatest responses in DM yield consistent with good nutritional quality for livestock production.     

Agro-climatic favorability zones for sugarcane orange rust as a tool for cultivar choice and disease management

Australia and Brazil are among the most important sugarcane producers in the world. Even under favorable climatic conditions, the yields in these regions are often limited by several factors, including fungal diseases. Sugarcane orange rust (SOR), caused by Puccinia kuehnii, is one of the most severe fungal diseases and can cause extensive losses in susceptible cultivars. Considering the significant influence climatic conditions can exert on SOR, the present study had as its aims, firstly, evaluation of weather data during SOR epidemics in the state of Queensland, Australia, in 1999/2000, and the state of São Paulo, Brazil, in 2009/2010; and secondly, development of a predictive model for SOR occurrence and severity, for identifying agro-climatic favorability zones for this disease in these regions. The results showed that SOR climatic favorability was highest on east of Queensland and in the center-east region of São Paulo, where air temperature and humidity were favorable for the epidemics. This information can help growers to avoid the use of susceptible cultivars in those zones where SOR poses the greatest risk, and to optimize strategies for chemical control of the disease.     

农杆菌介导的DnMADS2基因转化金钗石斛初步研究

为建立稳定有效的金钗石斛转化体系,进一步研究花发育相关基因的功能,为石斛兰分子育种提供基础,本研究以金钗石斛类原球茎（PLBs）为转化受体,通过农杆菌介导的方法将DnMADS2基因转入金钗石斛。结果表明：用20 mg/L潮霉素筛选4个月后获得抗性PLBs,对其进行HPT基因和DnMADS2基因的PCR检测表明,目的基因已成功整合到PLBs中。获得的转化PLBs在抗性培养基上分化为不定芽后,再经生根壮苗培养获得转化植株。对转化植株进行Southern检测,结果表明,DnMADS2基因已整合到5株金钗石斛转化植株基因组中。据此建立的稳定高效的金钗石斛转化体系和获得的转基因植株,将为DnMADS2基因功能的进一步研究和金钗石斛转基因育种奠定基础。     

Imidacloprid can reduce the impact of the whitegrub Antitrogus parvulus on Australian sugarcane

Management of Childers canegrubs, Antitrogus parvulus Britton, is heavily dependant on organophosphate insecticides. As part of a programme to develop and integrate a wider spectrum of controls, we tested the potential of imidacloprid to control existing infestations of third-instar larvae in sugarcane. Two SC and one WG formulation of imidacloprid (Confidor^®) were tested in 11 trials near Bundaberg or Childers in southern Queensland. These defined useful application rates for the formulations, compared the efficacy of formulations, tested surface and subsurface placement, tested different spacings of the coulters behind which the insecticide was applied, and compared the efficacy of early and late applications of the insecticide. Comparisons were made with cadusafos (Rugby^® 100 G). Kill of larvae was not as rapid or great as following treatment with cadusafos, but surviving larvae appeared not to be feeding as much. Both SC formulations at rates of at least 3.75 g active ingredient/100 m of row applied into the soil behind coulters placed either side of the stool gave similar gains in cane yield to applications of cadusafos. The WG formulation showed some responses, but was not tested extensively. Application to the soil surface was not as effective as injection into the soil behind coulters. Efficacy seemed to be largely unaffected by the spacing between the coulters. Early applications appear to be more effective than later applications, and lead to larger yield responses. Imidacloprid provides a way of treating infested ratoon crops, does not degrade in high-pH soils, and can be used in rotation with the organophosphate-based cadusafos and chlorpyrifos (suSCon^® Blue) to minimise the development of insecticide resistance.     

Understanding and modeling the effect of temperature and daylength on soybean phenology under high-yield conditions

Temperature and photoperiod can be used to simulate soybean (Glycine max [L.] Merr) phenology because they serve as surrogates for complex biochemical pathways leading to the appearance of certain developmental stages at the whole plant level. We developed a soybean phenology model (SOYDEV) which utilizes non-linear temperature and photoperiod functions and separates floral induction and post-induction for simulating time of flowering. This model accurately simulated the dynamics of vegetative development, final node number and the occurrence of major reproductive stages such as flowering (R₁), beginning pod (R₃), mid-pod elongation (R_3.5), beginning seed (R₅), and physiological maturity (R₇) in a long-term field experiment (6 years) with the semi-determinate soybean cv. NE3001, as well as in a 2-year cultivar × sowing date experiment with 12 (2004) and 8 (2005) cultivars. With cultivar-specific model calibration, root mean square errors (RMSE) of major phenological stages simulated with SOYDEV averaged 1.8 days in the long-term experiment and 3.3 days in the cultivar × sowing date experiment. Data from the cultivar × sowing date experiment were used to develop empirical relationships for estimating key cultivar-specific model parameters from published soybean maturity group ratings (0.8–4.2). Compared to using nine cultivar-specific parameters derived from the full calibration, estimation of model parameters from readily available cultivar information such as maturity group rating only slightly decreased simulation accuracy, resulting in RMSE (across stages and cultivars) values of 3.6–3.8 days. The proposed SOYDEV model may be particularly suitable for practical model applications because of its reduced need for cultivar-specific calibration. Further evaluation of the model is required under a wider range of variety maturity group ratings and environments.     

脱毒小薯兰地特气体催芽技术研究

以药剂浓度和熏蒸时间为处理进行了二因素四水平交叉试验。结果表明：以０．３３ｍｌ／ｋｇ／３ｈ处理小薯发芽率最高，且发芽势最强。由于不同品种对药剂作用反应程度不同，研究提出不同品种气体催芽可在０．１３～０．３３ｍｌ／ｋｇ／３～９ｈ的处理范围内选择使用。同时，为了明确药剂使用浓度超过０．５ｍｌ／ｋｇ时是否会造成小薯丧失发芽力，将熏蒸后未能发芽的小薯用３０ｐｐｍ的赤霉素浸泡２５ｍｉｎ处理，３品种均有９０％以上小薯发芽。表明在一定范围内（药剂浓度≤０．７３ｍｌ／ｋｇ，熏蒸时间≤１２ｈ），气体催芽可能抑制小薯发芽，但不会造成其发芽力丧失。     

Effect of green-belly stink bug,Dichelops furcatus (F.) on wheat yield and development

The green belly stink bug, Dichelops furcatus (F.) (Hemiptera: Heteroptera: Pentatomidae) is a pest of corn and soybean in southern Brazil. It also occurs on wheat, but information on its damage to this crop is limited. To determine the need for sustainable IPM programs, the impact of this bug on wheat production should be determined. Studies were conducted in the screenhouse with 1, 2 and 4 bugs caged for 16 days on single plants, cv. ‘BRS Parrudo’. During the vegetative period (plants ca. 25 cm tall), all infestation levels significantly reduced plant height and ear head length, but did not reduce grain yield. Feeding damage caused tissue necrosis on leaves. During the booting stage, grain yield was significantly reduced with 2 and 4 bugs per plant; ear heads were small, discolored and abnormally developed. In 2013 and 2014 field trials, plants were infested for 18 days with 2, 4 and 8 bugs per m² at vegetative, booting, and milky grain stage. At these infestation levels, there was no significant reduction in grain yield. There was a significant decrease in the number of normal seedlings resulting from seeds exposed to 8 bugs per m² at the milky grain stage. Results suggest that, in general, there is no need to control D. furcatus on wheat, unless numbers are ≥8 bugs per m² during reproductive period.