Ruminal in situ disappearance kinetics of six nutritive ingredients in leaves and stems of young tetraploid black locust in growing steers

Tetraploid black locust (Robinia pseudoacacia) is a woody plant with larger leaves and richer nutritional content than normal diploid black locust, with greater biomass and wider adaptability than herbaceous plant forage. However, currently no stockbreeders have adopted it as a major forage in China and other countries for a lack of information on the evaluation of nutritional ingredients of leaves and stems of young tetraploid black locust (YTBL) by in situ digesting tests. The objectives of this study wer...     

刺槐同源四倍体种子促萌措施研究

为了最大限度地保存刺槐同源四倍体有性繁殖过程中产生的变异材料资源,对其高度变异和难以萌发的种子进行了促萌试验。结果表明:①种子经温汤浸种可以明显地提高萌发率, 90℃温水浸泡24 h,种子平均萌发率为5%、最高5.5%;②用PEG-6000处理刺槐同源四倍体种子时,平均萌发率1.11%、最高3.33%,表现为抑制作用;③5-氮杂胞苷浸种时,药液浓度对萌发率有显著的影响,用250 μmol/ L的5-氮杂胞苷水溶液处理种子24～48 h为较好处理方案,平均萌发率为5.6%;④种子培养促萌时,用10% H2O2浸泡24 h后转入赤霉素水溶液（3 mg/L）浸泡6 h,之后再转入萘乙酸水溶液（15 mg/L）浸泡6 h,接种到MS或1/2MS培养基上促萌效果较好,平均萌发率为5.5%、最高6.0%;⑤将表型正常的种子胚接种到没有附加物的MS培养基上,有部分种子胚萌动后子叶变绿且张开。      

油菜不同氮素籽粒生产效率品种氮素积累与分配特征

2007—2008年度以98个甘蓝型常规油菜品种(系)为材料, 在不施氮肥(N₀)和纯氮150 kg hm^–2 (N₁) 2个处理下, 通过测定成熟期不同器官干重、氮素含量, 采用组内最小平方和动态聚类方法对供试品种的氮素籽粒生产效率(NUEg)聚类并分析其氮素积累与分配差异。结果表明, 不同品种氮素籽粒生产效率差异较大, 类型间差异极显著。不同类型品种随着氮素籽粒生产效率增加, 产量增加。相关分析表明, 氮素籽粒生产效率与成熟期氮素吸收总量之间相关不显著(r_N0= –0.0245, r_N1= –0.1131), 与成熟期茎秆氮素分配比例(r_N0= –0.5941^**, r_N1= –0.4141^**)和果壳氮素分配比例(r_N0= –0.6007^**, r_N1= –0.5374^**)呈极显著负相关, 与籽粒氮素分配比例(r_N0= 0.7954^**, r_N1= 0.7239^**)呈极显著正相关;与成熟期总籽粒数呈极显著正相关(r_N0= 0.5945^**, r_N1= 0.5412^**)。氮素籽粒生产效率和氮素吸收总量对产量都有显著影响, 油菜品种的选育应在一定氮素吸收总量基础上, 促进后期氮素从营养器官向籽粒中输送, 提高氮素籽粒生产效率, 从而达到高产和高氮素利用效率的统一。     

Relationship Between Substrate Water Content and Weight Loss,Mycelium Culture Time and Hypsizygus marmoreus Growth Yields

Changes in the weight and water content of the growth substrate at different cultivation times significantly affected Hypsizygus marmoreus growth yields.Highest growth yields(132.6~146.3 g per culture) were achieved when the mycelium culture and maturation period was between 80 and 90 days,and the substrate water content was 73%~74%.Physiological maturation of H.marmoreus mycelium was correlated with the substrate water content.     

Identifying future research needs in landscape genetics: where to from here?

Landscape genetics is an emerging interdisciplinary field that combines methods and concepts from population genetics, landscape ecology, and spatial statistics. The interest in landscape genetics is steadily increasing, and the field is evolving rapidly. We here outline four major challenges for future landscape genetic research that were identified during an international landscape genetics workshop. These challenges include (1) the identification of appropriate spatial and temporal scales; (2) current analytical limitations; (3) the expansion of the current focus in landscape genetics; and (4) interdisciplinary communication and education. Addressing these research challenges will greatly improve landscape genetic applications, and positively contribute to the future growth of this promising field. Participants of the Landscape Genetics Research Agenda Workshop, held at the 2007 World Congress of the International Association of Landscape Ecologists (IALE), in Wageningen, The Netherlands: Paul Arens, Pascal Campagne, Virginia H. Dale, Alfredo G. Nicieza, Marinus J. M. Smulders, Edoardo Tedesco, Hongfang Wang, Tzeidle Wasserman.     

陆地棉显性无腺体品系杂种优势及配合力研究

以７个显性无腺体陆地棉品系和４个常规品种（系）为材料，按ＮＣＩ设计，对２８个组合的杂种Ｆ１进行了分析。结果表明。杂种Ｆ１具有明显的优势，２８个组合所研究的１５个性状中全部具有中亲优势，６个性状具有高亲优势，４个性状具有竞争优势；配合力分析的１１个性状中，株高、衣分、纤维长度和麦克隆值主要受基因加性效应控制，而子棉产量、皮棉产量、单株铃数、铃重和子指等性状同时受基因加性和非加性效应作用，显无０７３是丰产的显性无腺体品系，而显无２６０是较好的优良品系，组合显无０７３Ｘ泗棉２号在重要性上表现较好。     

豇豆胰蛋白酶抑制剂(CpTI)抗虫转基因新疆杨的获得

利用根癌农杆菌介导法将广谱抗虫基因豇豆胰蛋白酶抑制剂(CpTI)基因导入新疆杨(Populus a1-ba var．pyramidalis)，经筛选获得了大量转基因植株。对转基因植株经PCR鉴定、PCR-Southern和点杂交分子检测结果证实CpTI基因已整合进杨树基因组中。部分转基因植株的饲虫实验表明，饲喂转基因杨树叶片可明显抑制杨尺蠖幼虫生长发育。     

黄麻染色体组型研究

本文比较研究了圆果黄麻“粤圆5号”和长果黄麻“翠绿”的染色体组型。结果是:圆果黄麻和长果黄麻的染色体组型均为 K(2n)=14=12M+2M~(sat),即其染色体均属于中部着丝粒染色体。前者的第5对染色体为随体染色体,后者的第6对染色体为随体染色体。     

Constitutive Expression of Sense & Antisense PtAP3, an AP3 Homologue Gene of Populus tomentosa, Affects Growth and Flowering Time in Transgenic To-bacco

To analyze the function of PtAP3, an APETALA3 (AP3) homologue gene isolated from Populus tomentosa Carr., the full length sequence (1 797 bp) and a fragment (870 bp) of PtAP3 were fused to a CaMV 35S promoter of pBI121 to generate the sense and antisense constructs of PtAP3. These constructs were transformed into tobacco by Agrobacterium infection of leaf disks and selection on kanamycin medium. Some sense and antisense transgenic tobacco plants were obtained by PCR and Southern blot analysis. Great phenotypic differences in transgenic tobacco plants were observed. Almost all of sense PtAP3 to transgenic tobaccos showed a higher growth rate than those of antisense transformants and a few developed pregnancy earlier than wild type seedlings and antisense transformants under the same conditions.     

克服棉属种间杂交不亲和性的研究

陆地棉（Ｇ．ｈｉｒｓｕｔｕｍＬ．２ｎ＝５２）与亚洲棉（Ｇ．ａｒｂｏｒｅｕｍＬ．２ｎ＝２６）杂交，由于种间隔离，遗传机制差异较大，不易结实，我们多年研究结果表明，棉属（Ｇｏｓｓｙｐｉｕｍ）种间杂交由于选配的亲本不同Ｆ０代的成胚频率差异很大，选择植株呼吸强度大，叶绿素ａ含量高和主要经济性状如单铃重、单铃种子数、子指等一般配全力较高的棉种作亲本，可以显著提高杂交当代的成胚率。