24份甜橙种质资源的ISSR分析

从97条ISSR引物中筛选出14条能扩增出清晰的具有多态性DNA谱带的引物,分别对24份甜橙种质基因组总DNA进行PCR扩增,共获得147个位点,其中54个位点具有多态性。利用SPSS13.0软件对数据进行分析,结果显示,24份甜橙种质间相似系数在0.815~0.983之间,表明24份甜橙种质间亲缘关系较近;相似系数在0.851处,24份甜橙种质被分为3组,ISSR分子标记的分析结果与形态学观察及传统分类结果基本吻合。通过对PCR扩增谱带的分析,结果显示,引物CW39119为‘奈维林娜脐橙’种质的特异性标记,引物CW32439为‘红肉脐橙’红梗与白梗种质的特异性标记,引物CW32445为‘纽荷尔脐橙’与‘脐橙52号’种质的特异性标记。     

枇杷新品种‘东湖早’的ISSR分子鉴定

利用ISSR分子标记技术,鉴定枇杷新品种‘东湖早’。从95条引物中筛选出能稳定扩增的11条引物对‘东湖早’及选定作为对照的22个枇杷品种总DNA进行PCR扩增。构建基于ISSR数据的UPGMA树状图,结果共获得141个位点,有88个多态性位点,多态性百分率为62.41%。‘东湖早’与对照种相似系数处于0.560～0.838之间,与‘太城4号’相似系数最大为0.838。     

福建柚类种质资源的ISSR分析

从100条ISSR引物中筛选出14条具有多态性谱带的引物,对福建柚类16份种质资源进行ISSR分析。结果显示:14条引物共扩增出177个位点,有123个多态性位点,多态性百分率为69.49%,福建柚类种质资源的相似系数在0.526~0.984之间。其中,‘胡柚’与‘三明金柚’相似系数最高,为0.984;‘澳洲柚’与‘土柚’相似系数最低,为0.526。相似系数在0.553处,16份种质可分为两大类,‘胡柚’、‘三明金柚’、‘澳洲柚’、‘福柚’及‘新路比葡萄柚’属第一大类,其余柚类种质为第二大类。     

‘赣南早'脐橙在干旱胁迫下的生理及转录组研究

我国脐橙产区的季节性干旱对脐橙产量和品质影响较大。‘赣南早'脐橙作为一个新品种脐橙,目前在我国脐橙产区已大面积推广。为深入了解这个新品种的耐旱性,探究早熟品种‘赣南早'脐橙应对干旱胁迫的调控机制,以‘赣南早'脐橙与‘纽荷尔'脐橙（对照）为材料,测定比较不同干旱胁迫程度下二者光合作用、干旱相关生理指标等差异,并通过RNA-Seq分析比较转录水平差异及抗氧化物酶基因表达调控。结果表明：干旱胁迫下‘赣南早'脐橙净光合速率（P_n）、蒸腾速率（T_r）、气孔导度（G_s）均显著高于‘纽荷尔'脐橙;随着干旱胁迫程度增加,‘赣南早'脐橙叶片较‘纽荷尔'脐橙更舒展,‘赣南早'脐橙相对电导率和丙二醛含量显著低于‘纽荷尔'脐橙,而保护酶超氧化物歧化酶（SOD）和过氧化物歧化酶（POD）活性变化幅度更大;‘赣南早'脐橙和‘纽荷尔'脐橙叶片可溶性糖含量无显著性差异,复水后,‘纽荷尔'脐橙叶片中可溶性糖含量极显著高于‘赣南早'脐橙。转录组测序分析表明,干旱胁迫0、10、20 d时,‘赣南早'脐橙和‘纽荷尔'脐橙间DEGs数量分别为1266、683、658个。GO富集分析显示,在干旱胁迫过程中‘赣南早'脐橙差异基因主要集中在细胞蛋白修饰过程、高分子修饰作用、含磷化合物代谢过程、蛋白修饰过程等通路,而‘纽荷尔'脐橙未见明显富集。KEGG富集分析显示,除了富集于淀粉及蔗糖通路和氨基酸及核苷酸糖代谢途径,‘赣南早'脐橙其他差异基因富集途径与‘纽荷尔'脐橙基本一致。差异基因转录因子分析显示二者在ERF家族、MYB家族、NAC家族、MYB_related家族、WRKY家族、bHLH家族、HB-other家族、HSF家族、B3家族和bZIP家族均有分布,此外,‘赣南早'脐橙特异分布于GRAS家族。根据转录组分析筛选出抗氧化酶相关基因30个,其中上调表达48%,下调表达52%。本研究结果为‘赣南早'响应干旱胁迫的生理变化提供理论依据,并为其抗旱性研究提供分子基础。     

杂交水稻种子纯度分子鉴定技术研究

为了鉴定杂交水稻种子的纯度,用49条ISSR引物时供试的5组三系杂交水稻F1和父母本进行扩增,结果28条引物能扩增出DNA带,随机选取其中3条引物用于指纹分析,3条ISSR引物共扩增出32条DNA带,其中多态性条带为27条,并将这些多态性条带进行聚类分析。     

山地纽荷尔脐橙高产、优质栽培技术

屏南县山地栽培纽荷尔脐橙，要达到高产优质目的，其果园的建立、栽植方法、肥水管理、树形整修、病虫害防治每个环节都很关键。本文通过几年的实践及栽培研究，总结了山地纽荷尔脐橙栽培管理技术。     

利用ISSR构建甜菜品种指纹图谱

为了快速、准确鉴定甜菜品种,采用ISSR分子标记对39个甜菜品种进行扩增并构建其指纹图谱。利用8个不同的甜菜品种DNA进行引物筛选,在100条ISSR引物中筛选出4条扩增条带清晰、多态性好的引物,对39个甜菜品种进行PCR扩增,构建甜菜品种指纹图谱。结果表明,2条ISSR引物ISSR826和ISSR827扩增条带多态性为71.4%～90.0%(平均85.2%),利用该2条构建的指纹图谱就可以完全区分39个甜菜品种的真实性和纯度。甜菜品种指纹图谱的构建为甜菜品种的鉴定、区分,为科学、快速、高效鉴定甜菜品种,保护科研工作者以及农民的利益提供理论依据。     

橡胶树尖孢炭疽菌分子检测及遗传多态性分析

根据GeneBank中Colletotrichum属的20个种的ITS序列,比较设计出1对引物CAF53/CAR356(CAF53 5’-GGG CAG GGG AAG CCT CTC G-3’;CAR356 5’-AGC GGT GCT TGA GGG TTG-3’);该引物可以扩增出1条303 bp的尖孢炭疽菌特异性DNA条带。并利用ISSR和RAPD分子标记技术对从海南、广东、广西和云南等垦区橡胶树上收集的21个尖孢炭疽菌株进行遗传多态性分析,以杧果上分离的尖孢作为参照菌株进行了聚类分析。结果表明,RAPD的平均遗传相似系数为0.8,ISSR的平均遗传相似系数为0.7,2种分子标记的平均遗传相似系数基本一致,均可揭示尖孢炭疽病菌的遗传多态性;2种分子标记产生的聚类分析结果存在一定差异;ISSR和RAPD类群与菌株的地理来源均不存在相关性。     

不同品种（系）凤凰单丛茶DNA指纹图谱的构建

为能够快速、准确地对不同品种（系）凤凰单丛茶进行鉴定,建立不同品种（系）凤凰单丛茶的DNA指纹图谱,本研究利用ISSR分子标记技术,以4份凤凰单丛茶品种为材料,对UBC802~UBC899等58条ISSR引物进行筛选,得到了12条多态性好的ISSR引物。在确定引物最佳退火温度后,利用这12条ISSR引物对39份凤凰单丛茶进行了扩增,结果显示,从其中筛选出的6条核心引物共扩增出84条带,平均每个引物扩增出14条带,其中多态性条带78条,多态性条带比例为92.86%,多态信息量平均为0.9456,其中引物UBC843多态性最为丰富,品种相似性系数在0.4063~0.9836之间;为将39份凤凰单丛茶品种全部区分开,本研究对6条核心引物进行了组合,发现其中UBC827/UBC846的组合鉴别效率最高;通过综合品种名称、国家地区编号、采样地点、高效核心引物组合名称以及ISSR数据代码,本研究建立了39种凤凰单丛茶的DNA指纹代码。之后,通过整合软件录入如品种指纹图谱代码、香型、海拔、ISSR-PCR扩增数据图片等更多相关信息,形成指纹图谱二维编码,构成凤凰单丛茶的DNA指纹图谱,为凤凰单丛茶品种权益保护及信息平台的建立提供数据支持。     

利用ISSR标记技术鉴定甜玉米种子纯度的研究

利用ISSR技术对3个甜玉米组合及其父、母本自交系共9个材料进行鉴定,从30条引物中筛选出4条扩增条带清晰、多态性较高的引物,共扩增出31条DNA带,其中24条DNA带具有多态性,多态性比率为77.4%。对9个玉米材料的亲缘关系进行聚类分析,9个甜玉米材料分为两个类群。     

脐橙CsACBPs基因家族在果皮褐变过程中的表达分析

脐橙(Citrus sinensis Osbeck)果皮褐变,不仅影响果实外观,更降低口感风味,削弱商品价值.酰基辅酶A结合蛋白(ACBP)是乙酰辅酶A(Acetyl-CoA)的跨膜转运载体,帮助乙酰辅酶A在体内完成三羧酸循环,对植物的生长发育起到关键作用.已有文献报道ACBP家族中的基因对植物胁迫有应答,并且在脐橙果皮褐变相关基因的cDNA抑制差减文库中该基因也有明显变化.为了明确柑橘果实褐变过程中该基因的作用,以“奉园72-1”脐橙果实为材料,取不同程度褐变的果皮,并从脐橙果皮褐变相关基因的cDNA抑制差减文库中筛选了与酰基辅酶A结合蛋白(ACBP)基因家族同源的EST序列CsA CBP1/4/5/6进行分析.结果表明:随着柑橘果皮褐变程度的加重,CsA CBP1/4/5/6基因表达上调,说明CsA CBPs基因与脐橙果实褐变密切相关.     

Status of Sitodiplosis mosellana (Diptera: Cecidomyiidae) and its parasitoid,Macroglenes penetrans (Hymenoptera: Pteromalidae), in Montana

The orange wheat blossom midge, S. mosellana (Gehin) (Diptera: Cecidomyiidae), a global pest of wheat (Tritium aestivum L.), has recently invaded Montana's Golden Triangle, an important wheat producing region. Unchecked, S. mosellana populations can quickly grow to damaging levels. In this study, we document the prevalence of S. mosellana and its main natural enemy, Macroglenes penetrans (Hymenoptera: Pteromalidae), in this newly invaded area of Montana, and compared the effects of irrigated versus dryland cropping systems on S. mosellana and its parasitoid. Different approaches to monitoring S. mosellana populations were examined, including pheromone traps for adults, collection of larvae from wheat heads, and overwinter sampling of soil to measure the levels of larvae and cocoons. Adults of the M. penetrans were surveyed through daily sweep net sampling. This study demonstrated that the emergence of M. penetrans was usually well synchronized with emergence of S. mosellana as the emergence of parasitoids occurred shortly after the pest with the highest peak (90%) at 26 June and 14 July, 2015, respectively. Irrespective of sampling techniques; pheromone traps or soil sampling, no significant difference was observed in population of S. mosellana between irrigated and dryland cropping systems. In contrary, cropping systems played a significant role in the abundance of parasitoids since the irrigated fields had significantly higher population of parasitoids (five times on an average) compared to dryland cropping system. The possible implications of these findings in monitoring of S. mosellane and the establishment of M. penetrans are discussed.     

Chemical composition and selected functional properties of sweet orange (Citrus sinensis) seed flour

Flour samples were prepared from dehulled and undehulledsweet orange (Citrus sinensis) seeds. The flour samples were evaluated for proximate composition, mineralcontent and selected functional properties. Proximate analysis showed a composition of 54.2% fat, 28.5% carbohydrate, 5.5% crude fiber, 3.1% crude protein and 2.5% ash for the dehulled orange seed flour (dry weight).Mineral analyses showed high levels of calcium and potassium in flour samples. Partially defatted and undefatted flour samples prepared from dehulled orangeseeds had least gelation concentrations of 10 and 12%(w/v), respectively. Water absorption capacity for thedefatted and undefatted dehulled flour samples were 240and 220%, respectively. Defatting improved oil absorptioncapacity of the orange seed flour by 84%. Emulsion activity, emulsion stability and foaming capacity decreasedfollowing defatting of flour. Foam prepared from defattedflour was less stable than that from full-fat flour.Incorporation of NaCl up to 0.2 M improved the foamingcapacity of orange seed flour.     

Evaluation of growth of Neosartorya spp. on some Nigerian fruit products

Growth of Neosartorya fischeri, N. fischeri var. spinosa and N. quadricincta on inoculated fruit juice agars (FJAs) consisting of 1% agar and juices from mango (MJA), orange (OJA) and pineapple (PJA) containing various levels of added sucrose was studied in terms of the average number of colonies produced by their ascospores, time (days) required before colonies were formed and developed to confluent mycelial mat as well as the level of reproductive spores produced. The means of the number of colonies on PJA and OJA without added sucrose were significantly (p =0.05) higher than that of MJA. Addition of sucrose at levels of 10% to PJA, 11.5% to OJA and 9% to MJA increased the numbers of colonies whereas sucrose levels of 30% or more in PJA, 31.5% or more in OJA and 29% or more in MJA decreased the number of colonies produced. At any level of added sucrose to FJAs, a significant (p =0.05) delay occurred before the colonies were formed and developed to confluent mycelial mat except in PJA containing 10% sucrose. All cultures produced abundant cleistothecia on all FJAs without added sucrose. Addition of sucrose at levels of 30% to PJA, 31.5% to OJA and 29% to MJA resulted in the production of abundant conidial heads with a corresponding decrease in the proportion of cleistothecia.     

Shelf life study of some Nigerian fruit juices inoculated with ascospores ofNeosartorya spp.

Mango, orange and pineapple juices containing various concentrations of sucrose were dispensed in 100 ml volumes into 100 ml conical flasks with stoppers. Each juice in a flask was inoculated with ascospores of one local isolate of eitherNeosartorya fischeri, N. fischeri var.spinosa orN. quadricincta to a final concentration of 120–140 ascospores/ml of juice, and then pasteurized at 80°C for 30 min. A set of 36 inoculated flasks with 12 controls was stored at 4–5°C and two sets, one protected with 100 mg/l sodium benzoate, were stored at room temperature (25–28°C). A shelf life study was carried out on all the juices for 64 days. Only fruit juices stored at 4–5°C and those containing sodium benzoate stored at room temperature were protected from spoilage by these fungi for 64 days. Addition of sucrose at levels of 9% to mango juice, 30% to pineapple juice and 31.5% to orange juice significantly (p=0.05) protected ascospores from inactivation during cold storage.     

甘蓝型油菜显性核不育橙黄花纯合两型系的选育

以甘蓝型油菜显性核不育杂合两型系的不育株沪油15A为母本,与恢复系HF03杂交,F1群体全部表现为可育。在该杂交组合的6个F3群体中有5个群体发生育性分离。其中区号为04-4307的F3群体发生育性和花瓣色泽的分离,表现为70株鲜黄花可育、22株鲜黄花不育、30株橙黄花可育、9株橙黄花不育。根据油菜显性核不育和橙黄花的遗传规律,04-4307出现3:1育性分离,说明该群体由基因型为MsMsRfrf的单株自交获得。从04-4307群体中选橙黄花可育株自交,并与橙黄花不育株作兄妹交,后代全部表现为橙黄花(y1y1y2y2)。其中区号为05-4356的兄妹交组合出现1:1育性分离;其父本的可育株自交出现3:1育性分离。由此推断,05-4356的兄妹交组合就是显性核不育橙黄花纯合两型系,其不育株基因型为MsMsrfrfy1y1y2y2,可育株基因型为MsMsRfrfy1y1y2y2。     

Studies on natural repellents against potato tuber moth (Phthorimaea operculella Zeller) in country stores

Summary The effects of the leaves of five plant species, one from each of the generaAmbrosia, Anemone, Eupatorium, Eucalyptus andLantana, on potato tuber moth were investigated under indigenous storage conditions at the Central Potato Research Station, Shillong (1800 m above sea level). Their action was compared with that of a biological insecticide (spores ofBacillus thuringiensis), a chemical insecticide (carbaryl), and an untreated control. The data collected after six months storage on tuber damage, sprout damage and the rotting indicated that the leaves ofLantana aculeata provided most protection to the tubers, reducing damage from over 70% in the check to below 5%, and sprout damage from over 45% to below 3%. Next best wasEucalyptus globulus followed byB. thuringiensis. They may be used on tubers stored for table use or for seed as they had no adverse effect on germination or on the yield of a subsequent crop.     

Comparative Assessment of the Efficacy of Various Nitrogen Fertilizers

Summary

The efficiency of N fertilizers is usually poor; often less than 50% of the applied N is taken up by the crop. This review focuses on various N fertilizers with respect to the significance of different N loss pathways, namely (i) ammonia volatilization, (ii) dinitrogen and nitrogen oxide emissions, and (iii) nitrate leaching. Further, the significance of biological N immobilization, ammonium fixation and, finally, the impact of nitrate vs. ammonium uptake on crop yield are also discussed. The reviewed literature shows that N fertilizers may differ markedly in their susceptibility to losses. There is, however, considerable scope to improve N efficiency of each N source by proper N management practices.