农杆菌介导法将热激转录因子8基因转入大豆

植物转化是开展基因工程育种和鉴定基因功能的重要途径。本研究的目的在于向大豆受体导入热激转录因子8（heat shock factor 8,hsf8)基因,以加强目的基因hsp70的表达和增加转基因大豆的抗逆性,同时探索提高大豆转化率的途径。本文以大豆子叶节为外植体,通过农杆菌介导法将hsf8基因转入栽培大豆品种科新3号中,获得了13株抗卡那霉素的转化植株。PCR检测表明,其中的9株呈阳性反应,证明hsf8基因已整合到大豆基因组中。本实验获得的实际转化率为2．39％。文中讨论了选择适宜的种子灭菌方法和大豆受体品种对提高转化率的有效作用。     

Factors affecting oat haploid production following oat × maize hybridization

Doubled haploids (DHs) are becoming increasingly important in crop breeding programmes but methods for producing oat DHs remain inefficient. In this study haploid and DH oat plants were produced using the oat × maize hybridization method. Factors influencing the rate of caryopsis and haploid embryo production including genotype, post‐pollination plant growth regulator application and temperature were investigated. The four growth regulators tested showed significant differences in their capacity to induce caryopsis formation with dicamba producing the highest numbers of caryopses, followed by picloram, 2,4‐dichlorophenoxyacetic acid (2,4‐D) and gibberellic acid (GA₃). No significant differences were observed between these growth regulators for their effect on embryo production. The concentration of dicamba was also important and was found to influence caryopsis but not embryo production, with 50 and 100 mg/l dicamba producing significantly more caryopses than 25 or 5 mg/l. Temperature had a significant impact on both caryopsis and embryo production with the magnitude and direction of response depending on genotype. Rates of haploid embryo production observed were between 0.8% and 6.7% of the pollinated florets. The proportion of haploids, which survived and were successfully doubled with colchicine following transfer to soil was between 72% and 81%.     

Evaluation on the Damage Evolution of the CRCP+AC Composite Pavement by the Concrete Dameged Plasticity Material Model

In the study on the CRCP+AC composite pavement, the form and distribution pattern of cracks are two important factors influencing the performance and the lifetime of the pavement. The concrete damaged plasticity material model incorporated in the general purpose finite element software named ABAUQS was adopted to describe the mechanical characteristics of the CRC slab. Combining with the temperature field database drawn from the three-dimensional transient heat transfer analysis, the structural damage under the condition of temperature changing is analyzed. The structural damage evolution and the crack behavior of the CRC slab subjected to the thermal-mechanical coupling condition are further analyzed, which suggests that the role of the asphalt concrete surface is not confined only to the scope of improving the performance of the road, its capacity for improving the stress state of CRCP slab is worthwhile to be affirmed. And the reasonable thickness of AC layer should be designed in consideration of the thermal contraction and damage properties of the CRC slab comprehensively.     

Optimal design of scroll compressor’s profiles with key parameters preference

Aiming at the problem around single optimal objective and solution selection without considering designer’s preference, optimal objective function combing maximum compression ratio and maximum coefficient of volume utilization is proposed in a liner weighting model based on defined variables. Furthermore, the main factors’ influence is evaluated by analytic hierarchy process (AHP) for its advantage of dealing with qualitative analysis data. The second selective preference is achieved by normalization and second liner weighting. The validity of the method is illustrated by a case study.     

Comprehensive Effects of Temperature and Relative Humidity on Rebar Corrosion in Concrete

The corrosion rate of steel in concrete is highly dependent on the heterogeneous structure of the concrete and the environmental exposure conditions. Temperature and relative humidity are two important environmental factors that simultaneously influence the corrosion process and cannot be separated or isolated from each other. The interaction of temperature and relative humidity for characterizing the corrosion rate has been sufficiently studied. The resules show that the higher the temperature is, the greater the relative humidity is when rebar corrosion rate reaches the max, and as to different relative humidity, the increasing extent of rebar corrosion rate with rise in temperature is different.     

池塘生态系基质C/N比对游离细菌群落生长和有机N矿化作用的影响

本文研究了向高产鱼池中人工添加有机C（葡萄糖）和有机N（甘氨酸）对水中游离细菌生长及其分解矿化有机N的影响。研究结果表明，向池塘水中添加有机C促进了细菌生长和细菌对N素的吸收；而添加有机N对细菌生长的影响不明显，但增强了有机N的矿化作用。在池塘水营养条件下，溶解有机C限制了细菌的生长，细菌在鱼池生态系统N循环中起着有机N分解者的作用。     

种植密度和施肥量对白瓜籽产量的影响

采用裂区试验设计,研究白瓜不同种植密度和施肥量对白瓜籽产量的影响。结果表明:处理3的产量较高,即667 m2施肥量18 kg,其中尿素4.5 kg,磷酸二铵4 kg,硫酸钾9.5 kg,密度为1 300株,白瓜籽产量可达67.03 kg。     

木耳新品种‘旗黑 1 号’

 木耳新品种‘旗黑1 号’,菌丝体洁白浓密,气生菌丝发达呈绒毛状,菌落边缘整齐。子实体单片簇生,黑色,单个耳片直径5 ~ 10 cm,厚0.10 ~ 0.13 cm。从接种到采收115 ~ 125 d。每100 kg 干料鲜耳产量为78.7 kg。抗绿霉等杂菌能力较强。     

四川幼龄橘园间作蚕豆绿色高效技术

四川是我国柑橘主产区之一,橘园开发利用潜力巨大。为充分利用橘园行间空地和光热资源,解决幼龄橘园前期效益低的问题,对幼龄橘园间作蚕豆模式可行性进行了探讨,同时从品种选择、种植模式、适期播种、病虫害防控等方面总结了蚕豆绿色高效栽培技术,以期为四川橘园综合利用提供新的种植模式和技术参考。     

抗戊唑醇苹果轮纹病菌的紫外诱导及其生物学特性

在含戊唑醇的马铃薯葡萄糖琼脂(PDA)培养基上,通过紫外线诱导获得了9株对戊唑醇具有不同抗性水平的苹果轮纹病菌 Botryosphaeria berengriana f.sp. piricola 抗药性突变体,其抗性指数在11.00~67.88之间。将该抗药性突变体继代培养9代后,大多数突变体的抗性指数逐渐下降,但其中有2 株抗药性突变体(UV-TS1-f和UV-TS1-10)仍保持较高的抗性水平;抗药性突变体的致病力与敏感菌株相比未发生明显变化;与敏感菌株一样,抗药性突变体适宜生长的温度也为25~28 ℃,pH值为7~8;在含不同碳、氮源的培养基中,抗药性突变体的菌丝生长与菌丝干重与敏感菌株相比差异明显。研究表明,苹果轮纹病菌在药剂选择压下易形成抗戊唑醇群体,具有中等或高抗药性风险。