中小花型蝴蝶兰杂交特性和无菌播种培养研究

为研究中小花型蝴蝶兰的杂交结实特性,提高育种技术和效率,选取9个中小花型蝴蝶兰品种作亲本按完全双列法进行自交与杂交,在81个组合中2个自交组合与17个杂交组合获得发育成熟的荚果,分别占自交组合数的22.2%和杂交组合数的23.6%.总平均结果率为12.3%,自交结果率为11.1%,杂交结果率为11.8%;作母本时9个品种平均结实率为13.63%,作父本时平均结实率为12.58%.蒴果生长呈S型曲线,可分为形成期、快速生长期和成熟期,各期时间长短受不同杂交组合的影响,快速生长期为30～50 d,从授粉到采收时间为80～118 d.种子萌发率及萌发所需时间因组合而异,平均萌发率为83.3%,杂交组合较自交种子启动萌发早、萌发率高.     

玉米杂交当代子粒灌浆特性的研究

对粒重不同的２个纯合稳定普通玉米自交系和２个爆裂玉米自交系及各自间正,反交４个杂交组合杂交当代的子粒灌浆特性研究结果表明：（１）各组合杂交当代的百粒重均高于母本自交系,超母本优势均为正值,平均及超父本优势依父,母本粒重的相对大小不同而异;（２）不同部位子粒百粒重均表现下部．〉中部〉上部,且授粉后２０ｄ差异较小,之后差异较大;（３）灌浆速率的高低和有效灌浆期 的长短时导致不同材料及不同部位子粒百粒重     

普甜玉米种子收获期与发芽率之间的关系研究

以3个普甜玉米高代稳定自交系[甜5、1636M(G)和南-1]和2个杂交组合[甜5×1636M(G)]F1、(南-1×甜5)F1为材料,研究普甜玉米种子不同收获期与发芽率之间的关系.结果表明,发芽率最高的收获期及其有效积温分别为普甜玉米自交系种子于授粉后的25～30d,授粉到收获有效积温为427.4～528℃;杂交组合F1代种子于授粉后30～35d,授粉到收获有效积温为528～620℃.     

普通小麦与粗山羊草正反杂交研究

【目的】研究普通小麦与粗山羊草杂交后的成胚率、成苗率及F1代的田间表现,为提高小麦的杂交成功率提供参考。【方法】以小麦矮败不育系(RH/CS)、中国春、辽春10号3个春性小麦及济南17和济麦20 2个冬性小麦为供试小麦材料,Y122、Y212、Y215为3个粗山羊草材料,先以小麦为母本,粗山羊草为父本构建正交组合,并在去雄后1~5d连续授粉,分析授粉次数对授粉率的影响,再以粗山羊草为母本,普通小麦为父本构建反交组合,分析各组合下胚、胚乳的形成情况;对正交组合进行幼胚拯救后,统计各组合的成胚率和成苗率;并将幼苗移至大田中,观察F1代的田间表现。【结果】小麦反交组合的授粉率(70.32%)远高于正交组合(8.51%),但正交和反交组合均未能形成种子,需要幼胚拯救才能获得后代;重复授粉可以提高授粉率;正交时春麦或者冬麦做母本对胚的形成和成苗率没有影响;胚培养最佳时间为13~18d;组培苗移入大田后成活率极低,仅为5.20%;杂交F1代成活单株有效分蘖数平均为263个。【结论】普通小麦×粗山羊草杂交后授粉2~3次,并于13~18d进行胚培养,可以提高杂交成功率。     

8个掖478玉米近缘系主要农艺性状的配合力及遗传分析

选用丹340、郑22、868作父本,8个掖478自交系近缘系作母本,采用NCⅡ设计组配24个杂交组合,对24个F1的9个主要农艺性状进行了一般配合力、特殊配合力及遗传参数分析。结果表明,24个组合9个性状的F检验均达显著或极显著水平。3个父本自交系9个性状的一般配合力存在极显著差异。8个掖478母本自交系各性状一般配合力方差除株高、穗位极显著外,其余7个性状均未达显著水平。株高、穗位、单株产量、穗行数、行粒数、百粒重和轴粗表现主要受加性基因效应影响,穗长、茎粗受加性、非加性基因效应共同影响。     

黄瓜种子胎萌生理特性及相关基因表达分析

[目的]探明黄瓜种子胎萌发生的生理生化特性及相关基因的表达模式,为揭示双子叶蔬菜类作物的胎萌发生机制提供理论依据.[方法]以黄瓜高代自交系Cs10A(易胎萌)和M-1(不胎萌)为试验材料,分别在授粉后30、35、40、45和50 d进行取样,统计黄瓜种子胎萌率,测定并分析种子中可溶性糖、脂肪酸、主要植物激素[脱落酸(ABA)和赤霉素(GA3)]含量及胎萌相关基因的表达模式.[结果]Cs10A种子在授粉后40 d发生胎萌,胎萌率为4.2%;在授粉后45和50 d Cs10A种子胎萌率极显著高于M-1(P<0.01,下同),分别为28.4%和71.1%.M-1授粉后30~50 d均未出现胎萌现象.授粉后30~50 d,Cs10A种子内可溶性糖含量呈先增加后降低的变化趋势,尤其在授粉后35~45 d显著(P<0.05,下同)或极显著高于M-1种子,而M-1种子可溶性糖含量呈增加─降低─增加的变化趋势.授粉后30~50 d,Cs10A种子脂肪酸含量呈先降低后增加的变化趋势,而M-1种子脂肪酸含量变化不明显,仅后期稍有增加,且在授粉后40 d时二者的脂肪酸含量非常接近,其他时间均存在极显著差异.授粉后50 d,Cs10A种子和囊衣中的ABA含量均极显著低于M-1;Cs10A种子和囊衣中的GA3含量均低于M-1,其中Cs10A囊衣中的GA3含量极显著低于M-1,但其种子中的GA3含量与M-1无显著差异(P>0.05);Cs10A种子中的GA3含量高于囊衣.Cs10A种子中ABA/GA3比值低于M-1种子.授粉后30~50 d,Cs10A种子中CsVp1、CsVp5和CsVp10基因的表达量均极显著低于M-1,其中,对于CsVp1和CsVp5基因表达模式而言,Cs10A与M-1恰好相反,但CsVp10基因在二者中的表达模式相同.[结论]种子发育成熟至发生胎萌前,种子中可溶性糖含量较高、ABA含量和ABA/GA3比值较低易导致种子发生胎萌,且种子中脂肪酸可转化成可溶性糖为种子胎萌的发生提供能源物质;囊衣中高含量ABA可有效抑制黄瓜种子胎萌的发生.此外,易胎萌黄瓜品种通过抑制与ABA合成及其敏感性相关的胎萌基因表达,从而降低ABA含量及对ABA的敏感性,最终导致胎萌发生.     

PEG胁迫对小麦代换系种子萌发特性的影响及染色体效应

[目的]明确干旱胁迫对中国春-Synthetic 6x代换系种子萌发特性的影响并对相关基因进行染色体定位,为选择抗旱高产品系提供理论依据.[方法]以小麦中国春-Synthetic 6x染色体代换系及其亲本为材料,设置对照(无离子水培养)和聚乙二醇(PEG)-6000模拟水分胁迫2个处理,通过测定种子的发芽率、发芽势、发芽指数研究干旱胁迫对种子萌发特性的影响及其染色体调控效应.[结果]干旱胁迫下,中国春-Synthetic 6x各代换系的发芽率、发芽势、发芽指数较对照普遍降低;5B、6B、4D、6D和7D代换系发芽率、发芽势、发芽指数均显著或极显著高于母本中国春.[结论] Synthetic 6x的5B、6B、4D、6D和7D染色体上可能存在干旱胁迫下提高种子活力、促进种子萌发的基因,可在抗旱育种中加以利用.     

黄花烟草(Nicotiana rustica)、迪勃纳氏烟草(Nicotiana debneyi)与Nicotiana tabacum K326互交亲和性的荧光鉴定

利用荧光显微镜对烟草互交组合Nicotiana tabacum K326×Nicotiana rustica与Nicotiana tabacum K326×Nicotiana debneyi授粉后花粉管生长部位和形态进行观察比较。结果显示,在正交组合中,N.rustica、N.debneyi花粉管大量生长进入Nicotiana tabacum K326花柱离柱头3/4区间后停止生长,在停止生长部位弯曲、膨胀,形成大量不规则胼胝质颗粒;用蒙导法、切割花柱法、已开放花朵授粉及已开花朵重复涂抹授粉等方法均未能有效促进2个父本花粉管在K326花柱中生长,而蕾期授粉花粉管可以生长进入子房,但授粉后没有获得种子;在反交组合中,K326花粉管可以在N.rustica、N.debneyi花柱中大量生长并进入子房,N.debneyi授粉后获得种子,种子萌发率为(49.67±1.53)%。     

苎麻种子含油量的配合力及遗传分析

以4个油纤兼用苎麻无性系为材料作完全双列杂交.分析杂交当代种子含油量的配合力和遗传效应.结果表明,供试材料种子含油量的一般配合力、特殊配合力和反交效应方差均达显著或极显著水平:不同材料一般配合力效应品系11>品系1>品系9>品系2.其中品系11和品系1为较理想的亲本材料:反交效应的大小和方向因组合而异.高含油量材料宜作母本还是作父本应视组合而定:含油量的广义遗传率为76.85%,狭义遗传率为41.38%,说明苎庥种子含油量的遗传率较高,且以基因加性效应为主;所有供试材料自交种子的舍油量均高于其作母本与其他材料杂交的种子舍油量.说明大面积种植同一无性系材料对舍油量没有不利效应.     

玉米杂交当代籽粒含水率遗传效应研究

为研究不同父本自交系对杂交当代籽粒含水率的影响,以籽粒脱水速率较慢的5个杂交种和5个自交系为母本,以脱水性能较好的5个早熟自交系为父本,10个母本分别人工授粉进行自交及与父本杂交,并对授粉后52天(DAP,d)的杂交当代籽粒及所有亲本材料的自交籽粒含水率进行了测试分析。结果表明:在早熟自交系授粉后,母本杂交授粉当代的籽粒含水率均值下降3.04个百分点,单粒干重比自交增加5.63%;母本自交系籽粒含水率均值下降2.85个百分点,单粒干重增加7.18%;当代杂交籽粒的含水率与父本呈正相关,表明玉米籽粒脱水性能具有父本效应,早熟父本可降低杂交当代籽粒的含水率。本研究可为玉米种质脱水性能的改良和选育快速脱水适宜机收的玉米品种提供参考。     

Web2.0,以个人为中心的互联网时代的到来

本文介绍了Web2．0的知识和背景，对Web2．0出现的基础以及典型技术和应用作了阐述，同时对其作出了前景展望。     

市级综合气象信息分析与管理系统的设计与实现

以抚顺地区3个国家基本站50余年气象资料为依托，采用Microsoft Excel工作表实现由气候和农业气候2部分构成的气象与农业综合信息处理系统的基本思路、方法、内容、用途和使用情况。为了实现气候分析及应用的科学化、客观化、系统化、规范化、程序化及连续化的业务目标，按业务流程设计与实现的，包括资料处理、气候趋势模拟、气候预测、气候鉴定、季节性信息化处理、农作物产量预报、气候生产潜力分析等一系列内容在内的系统建设。关键是解决了大量的计算问题，建立了区域性通用模式。     

Multi-variable grey model (MGM (1,n,q)) based on genetic algorithm and its application in urban water consumption

Urban water consumption has some characteristics of grey because it is influenced by economy, population, standard of living and so on. The multi-variable grey model （MGM（1,n））, as the expansion and complement of GM（1,1） model, reveals the relationship between restriction and stimulation among variables, and the genetic algorithm has the whole optimal and parallel characteristics. In this paper, the parameter q of MGM（1,n） model was optimized, and a multi-variable grey model （MGM（1 ,n,q）） was built by using the genetic algorithm. The model was validated by examining the urban water consumption from 1990 to 2003 in Dalian City. The result indicated that the multi-variable grey model （MGM（1,n,q）） based on genetic algorithm was better than MGM（1,n） model, and the MGM（1,n） model was better than MGM（1,1） model.     

Molecular detection of virulence genes in Campylobacter species isolated from livestock production systems in South Africa

Campylobacter species are a major cause of foodborne bacterial infections in both developed and developing countries worldwide. Campylobacter jejuni is responsible for the majority of infections. This study was conducted to identify virulenceassociated genes in Campylobacter species isolated from livestock production systems in South Africa. A total of 250 fecal samples consisting of cattle(n=50), chickens(n=50), goats(n=50), sheep(n=50) and pigs(n=50) were randomly collected from livestock in Eastern Cape and KwaZulu-Natal provinces of South Africa between April and October 2018. The samples were analyzed for the presence of virulence genes in Campylobacter species using molecular PCR-based methods. It was found that 77 and 23% of Campylobacter jejuni and Campylobacter coli respectively were isolated from all the livestock samples. There were positive significant(P0.05) correlations amongst all the virulence genes that were investigated. Chisquare and Fisher's exact tests were implemented to test for the effect of livestock species on the presence or absence of virulence genes. The study demonstrated that most of livestock species can potentially cause zoonotic infections and food poisoning due to the high prevalence of Campylobacter. The high prevalence of virulence genes highlights the significance of Campylobacter in livestock production systems in South Africa. This requires the implementation of one-health approaches to reduce the impact of foodborne and zoonotic diseases for the welfare of human and animal health.     

不同施肥水平对木薯氮磷钾养分积累、分配及其产量的影响

 【目的】通过比较不同施肥水平下木薯氮磷钾养分积累、分配和产量的差异，探讨粤北坡岗地优质高产木薯氮磷钾养分的最佳用量。【方法】以木薯品种南美119为材料，采用“3414”方案，在粤北翁源进行大田试验。试验共设14个处理。【结果】施肥处理的氮素主要分配到地上部，不施肥处理的氮素则主要分配到根部；不同施肥处理的磷素均主要分配到地上部；不施肥处理和不施钾处理的钾素主要分配到根部，不施氮处理的钾素在根、冠间分配较均衡。在木薯不同生长阶段，植株氮磷钾含量均呈下降趋势，但施氮、磷、钾化学肥料处理植株氮磷钾含量的下降速度小于不施氮、磷、钾化学肥料的处理。处理N2P2K2的氮、磷、钾含量和积累量在各生育期均为最大，不施肥处理（N0P0K0）的氮、磷、钾含量和积累量在各生育期均为最小（P＜0.05）。产量最高的是N2P3K2处理，为22 694.06 kg·hm-2，其次是N2P2K2处理，为21 417.87 kg·hm-2。【结论】木薯产量、氮磷钾养分积累及其在根冠间的分配，对施肥水平高度敏感, 适当比例的氮磷钾肥配合施用既可以显著增加木薯植株的氮磷钾含量和积累量，又可以提高产量。在粤北坡岗地木薯生产中，氮素最重要，在氮素得到满足的条件下，磷素较钾素更重要。在本试验条件下，氮磷钾养分最佳用量为358.80 kgN·hm-2、89.10 kg P2O5·hm-2和187.50 kg K2O·hm-2。     

红苕饲粮中添加铜和/或喹乙醇对猪生产性能及某些血液生化指标的影响

选体重约38公斤的长白(♂)×成华(♀)杂交猪20头,随机分为四组,饲予四种不同的饲粮,研究饲粮中添加铜和/或喹乙醇对猪生产性能和某些血液生化指标的影响。结果表明:基础组、加铜组、加喹乙醇组和两者同时加组全期日增重分别为674、761、796、678克,日采食量分别为2.50、2.65、2.74、2.40公斤,饲料利用率分别为3.73、3.49,3.44、3.54,添加铜和/或喹乙醇对试验第65天血清铜兰蛋白、尿素氨及屠宰率、背膘厚和眼肌面积无显著影响(p>0.05);添加铜使65天血清碱性碱酸酶活性极显著增高(p<0.01),添加喹乙醇有使之升高的趋势,两者同时添加时,碱性酸磷酶活性降低。     

Current progress on genetic interactions of rice with rice blast and sheath blight fungi

Analysis of genetic interactions between rice and its pathogenic fungi Magnaporthe oryzae and Rhizoctonia solani should lead to a better understanding of molecular mechanisms of host resistance, and the improvement of strategies to manage rice blast and sheath blight diseases. Currently, dozens of rice resistance (R) genes against specific races of the blast fungus have been described. Among them, ten were molecularly characterized and some were widely used for breeding for genetic resistance. The Pi-ta gene was one of the best characterized rice R genes. Following the elucidation of its molecular structure, interaction, distribution, and evolution, user friendly DNA markers were developed from portions of the cloned genes to facilitate the incorporations of the Pi-ta mediated resistance into improved rice varieties using marker assisted selection (MAS). However, rice blast is still a major threat for stable rice production because of race change mutations occurring in rice fields, which often overcome added resistance based on single R genes, and these virulent races of M. oryzae pose a continued challenge for blast control. For sheath blight, progress has been made on the exploration of novel sources of resistance from wild rice relatives and indica rice cultivars. A major quantitative trait locus (QTL), named qSB9-2, was recently verified in several mapping populations with different phenotyping methods, including greenhouse methods. The ability to identify qSB9-2 using greenhouse methods should accelerate the efforts on the qSB9-2 fine mapping and positional cloning.     

Virus Location and Lymphocyte Apoptosis in Lymph Nodes of Piglets Infected with PCV-2

The present study has been performed to understand the location of the virus, type of apoptotic cells, and their relation to lymph nodes of piglets infected with porcine circovirus type Ⅱ （PCV-2）. Nine 32-day-old conventional piglets free of infection with PCV-2 were used, and distributed into three groups： control group （n = 3）, piglets inoculated with PCV-2 alone （PCV-2, n = 3）, and PCV-2 inoculated and KLH immunostimulated group （PCV-2 ＋ KLH, n = 3）. Superficial inguinal lymph nodes from all piglets were collected for histological examination after 32 days postinoculation, and immunohistochemistry for PCV-2 detection. Location of apoptotic cells was detected with TdT-mediated dUTP nick end labeling （TUNEL） and cell cycle, and the apoptotic rates were measured by flow cytometry. The characteristic histopathological lesions of the piglets in PCV-2 and PCV-2 ＋ KLH were lymphocyte depletions in the cortex and paracortex of the lymph nodes, epithelioid-like macrophage infiltration, and intracytoplasmic inclusion bodies presented in epithelioid-like macrophages. PCV-2 was mainly found in epithelioid-like macrophages by immunohistochemistry. In the lymph nodes, lymphocytes presented higher apoptotic rates in the cortex by TUNEL, special B-cell areas, and similar apoptotic cells were found in this compartment in the control. The apoptotic rates of the lymph nodes were 0.41, 3.34, and 4.88% in the control, PCV-2, and PCV-2 ＋ KLH groups by flow cytometry, respectively. The apoptotic rates of lymph nodes for PCV-2 and PCV-2 ＋ KLH piglets were significantly higher than those for the control group （P〈0.05 and P〈0.01）. The proliferation index （PI） was 0.17_＋0.01, 0.12_＋0.01 and 0.12_＋0.04 in the control, PCV-2, and PCV-2 ＋ KLH group, the PI of the control group was higher than that of the other groups, but without the statistical difference. PCV-2 can induce lymphocyte depletion in lymph nodes of piglets by blocking cell proliferation and promoting apoptosis. This is one o     

锌对镉·汞复合污染下豌豆幼苗生长的影响

以豌豆为试验材料,采用水培方法研究了锌对镉、汞复合污染下的豌豆种子萌发与生长的影响。结果显示,锌浓度≤100.0 mg/L时促进豌豆种子的萌发,锌浓度为200.0和300.0 mg/L时抑制豌豆种子的萌发。当镉、汞的浓度为3.0 mg/L时,100.0 mg/L锌的解毒效应最明显,表现为能够促进镉、汞胁迫下豌豆种子萌发和幼苗生长,降低豌豆幼苗根尖细胞畸变率,提高豌豆幼苗的叶绿素含量及过氧化物酶活性;但当锌浓度≥200.0 mg/L时,与镉、汞协同迫害豌豆幼苗的生长。     

仙人掌超氧化物歧化酶提取与纯化研究

以仙人掌为试验材料,采用硫酸铵分级沉淀法得到超氧化物歧化酶（Superoxide Dismutase,SOD）粗酶液。然后用Sephadex（葡聚糖凝胶）G-75层析柱层析对粗酶液进行进一步纯化,最后用邻苯三酚法测定酶活力,并对酶活力主要影响因素（包括pH值、温度、抑制剂）进行了研究。结果显示仙人掌SOD酶比活力为751.56U.mg-1。pH值为7.5~8.5时酶活力最大,稳定性也好。温度维持在25~30℃时酶活力最高。由于过氧化氢和氰化钾均能使仙人掌SOD的酶活力显著下降,因而可以初步判断从仙人掌中提取到的SOD是Cu.Zn-SOD。