Effect of mannitol pretreatment to improve green plant regeneration on isolated microspore culture in Triticum turgidum ssp. durum cv. 'Jennah Khetifa'

The use of doubled haploids improves the efficiency of cultivar development in many crops and can be helpful in genetic and molecular studies. The major problem with this approach is the low efficiency of green plant regeneration. We describe here an efficient method for inducing embryos and regenerating green plants directly from isolated microspores of durum wheat cv. ‘Jennah Khetifa’. Tillers from donor plants were pretreated in 0.3 m mannitol and were stored at 4°C at various times: 3, 5, 6, 7, 8, 10 and 12 days. Our results showed clearly that the novel pretreatment combined mannitol 0.3 m and cold for 7 days had a strong effect on the number of embryos produced and regenerated green plants. Under this condition 13 475 mature embryos were produced from 2 693 500 microspores. Moreover, 85 green plants were obtained. High green plants regeneration frequency was recorded. As an average 11.55 green plants were produced per 100 000 microspores (about the equivalent of six plants per spike). Therefore, this study showed clearly that our results are the best ones published until now in durum wheat.     

Canola genotypes differ in potassium efficiency during vegetative growth

There is no knowledge about the differential capacity of canola genotypes to take up potassium (K) and produce dry matter under conditions of low soil K availability. Hence, 84 canola genotypes were screened for K efficiency in the glasshouse. Plants were grown in sealed pots containing K-responsive, sandy soil without or with K added. Twelve genotypes were selected for advanced screening in the glasshouse in a different K-responsive soil. Genotypes with a mean K efficiency ratio (the ratio of shoot dry weight at deficient and adequate K supply) greater than one standard error above or below the median genotype value were classified as K-efficient or K-inefficient, respectively. There were significant differences between genotypes in the K efficiency ratio in both screening experiments, indicating that genotypes responded differently to K availability. In the initial screening experiment, 19 genotypes were rated as K-efficient and nine genotypes rated as K-inefficient based on the K efficiency ratio. In the advanced screening experiment with 12 genotypes, three genotypes were rated as K-efficient and two as K-inefficient. Genotypes Wesbarker and Rainbow were K-efficient and Genkai K-inefficient in both experiments. Correlation of the K efficiency ratio with (i) shoot K content in the initial and advanced screening and (ii) shoot K concentration in the advanced screening, indicates that the observed differences in K efficiency were due to genotypic differences in both the uptake and the utilization of K. K-efficient genotypes have a potential to improve canola yields on soils with low K availability.     

香蕉抗病基因类似序列(RGA)的克隆与分析

根据植物NBS类抗病基因保守氨基酸序列P-loop和疏水氨基酸GLPL保守序列设计简并引物,从香蕉抗镰刀菌枯萎病(4号小种)材料IN21(Musa spp.cv). 'IN21',AA)和Rose(M.spp.cv.'rose',AAA)的基因组DNA中扩增获得4个RGA,四条DNA片段长度分别为527 bp、537 bp、534 bp和547 bp,分别命名为"RGA-IN1"、"RGA-IN2"、"RGA-Rosel"和"RGA-Rose2"(GenBank Accession:EF488469、EF488470、EF488471和EF488472);同源性分析表明,均与已报道的植物抗病基因有不同程度的同源性,具有P-loop、Kinase-2、RNBS-B(Kinase-3a)以及GLPL等保守氨基酸序列,属于non-TIR-NBS类候选抗病基因.     

不同类型水稻品种的产量与食味品质的关系比较

本试验采用辽宁省近年来主栽的13个水稻品种为试验材料,研究不同类型水稻品种的产量与品质间的差异和相互关系,以期为高产优质栽培及育种提供理论基础.结果表明:不同类型水稻品种的产量为:密穗型>中间型>散穗型.密穗型品种的成粒数、总颖花数均高于散穗型品种.密穗型品种的食味值高于散穗型品种;密穗型品种的蛋白质含量低于散穗型品种.着粒密度8.5～9.2粒/cm,320万～330万穗/hm2,每穗颖花数150～170个,成粒数达125～150粒/穗,产量和食味品质均能达到较高水平,因此,中间类型品种具有更高产优质的潜力.     

适合AFLP分析用的节瓜基因组DNA提取方法的研究

本研究以CTAB法为基础,采用以下5种处理提取节瓜叶片基因组DNA:A、PVPP(3%)+抗坏血酸(100 mmol/L);B、β-巯基乙醇(3%)+抗坏血酸(100 mmol/L):C、PVPP(3%)+半胱氨酸(5%);D、PVPP(3%)+β-巯基乙醇(3%);E、抗坏血酸(100 mmol/L)+半胱氨酸(5%).实验结果表明:在5种处理中,C处理提取的DNA质量最高,其溶液呈无色透明状,经核酸蛋白仪测定其OD260/OD280为1.8～2.0;经0.8%琼脂糖凝胶电泳检测,节瓜叶片基因组DNA带型清晰、完整、无降解,蛋白、多糖、酚类及RNA等去除比较彻底;经AFLP分析,酶切彻底,PCR扩增后的带型清晰稳定,重复性好,说明C处理提取的节瓜基因组DNA完全满足AFLP分析的要求.     

基于农业循环经济理论的山西省新农村建设研究

循环经济是一种新型经济发展模式,发展循环经济是实现我国经济社会可持续发展战略的重要途径。大力发展农业循环经济,是推进新农村建设的突破口,对于农业生产条件薄弱的山西省具有十分重要的意义。在介绍农业循环经济理论的基础上,分析了农业循环经济与山西省新农村建设的关系,指出了山西省新农村建设中发展农业循环经济的阻碍,进而提出山西省发展农业循环经济的对策。     

不同基因型香料烟叶片发育过程中碳氮代谢关键酶活性及代谢产物变化

摘 要：研究了浙江新昌不同基因型香料烟叶片发育过程中碳氮代谢关键酶的活性及代谢产物的含量变化规律。结果表明,在香料烟叶片发育过程中,酸性转化酶(INV)的活性均呈下降趋势;谷氨酰胺合成酶（GS）的活性Samsun品种在20d叶龄时最高,而Basma和Canik在30d叶龄时最高;苯丙氨酸解氨酶（PAL）的活性均表现为30d时最低;随着叶片成熟总氮含量降低,烟碱含量升高,总碳、可溶性总糖随着叶片成熟其含量呈升高趋势;品种不同,碳氮代谢关键酶的活性及代谢产物的含量变化均有很大差异。     

叶片结构与柑橘溃疡病抗性的初步研究

摘要: 对5个柑橘品种（稻叶温州蜜柑[Citrus unshiu (L.) var. Inaba]、春见[(C. reticulata × C. sinensis) var. Okitsu No. 44]、卡拉卡拉红肉脐橙[C. sinensis (O.) var. Cara Cara]、玫瑰橙[C. Sinensis var. Meiguicheng]和HB柚[C. grandis (L.) var. HB]） 的夏梢老熟叶片气孔及其显微结构进行解剖构造的观察和测定。结果表明：不同品种间叶片的气孔密度差异显著,并且与品种抗病性成正相关,其相关系数为0.888;可以把叶片气孔的密度作为抗柑橘溃疡病的形态结构的初步鉴定指标。不同品种间叶片的显微结构特征差异不显著,与品种抗病性相关性不显著,品种间变化规律性不强。     

“天宝香蕉”产业化技术模式应用与成效分析

芗城区为打好“天宝香蕉”品牌,推动产业提质增效和可持续发展,通过项目实施,培育龙头企业作为项目实施载体,形成“龙头企业+农户+基地+标准”的技术模式,采用先进配套设备,搞好产业化经营,提高组织化程度;研究制定福建省地方标准《天宝香蕉》标准文本,应用利益驱动原则,引导农户加快标准化生产技术的应用推广,确保香蕉品质优化与食品安全,“天宝香蕉”获国家地理标志保护产品。项目实施采取加强组织领导,建立示范基地,健全科技推广网络,开展优质科技服务。两年来,示范面积152.7hm2,推广面积2066.7hm2,平均产量34932 kg/hm2,新增产量1.17万t,新增产值3529.1万元;节省成本373.6万元;产投比2.6。对推动福建省发展优质、丰产、安全、高效的香蕉产业具有重要意义。     

不同叶位叶片对水稻籽粒充实的影响

采用8个水稻品种,抽穗期进行剪叶处理,研究不同叶位叶片对籽粒充实的影响.结果表明:剪叶降低水稻的成粒率、粒重,尤其对后开花的籽粒影响较大,从而降低籽粒产量.各部位叶片对弯曲穗型品种的籽粒充实作用大小依次为剑叶＞倒二叶＞其他叶片,而半直立穗型品种剑叶影响最大.剪叶处理会显著增加空秕粒率.半直立穗型品种各叶片对产量影响差异较小;弯曲穗型品种剑叶对产量的影响远大于其他各叶片,且剑叶对水稻产量的影响弯曲穗型品种远大于半直立穗型品种.