Collection and Characterization of Citrus indica Tanaka and C. macroptera Montr.: Wild Endangered Species of Northeastern India

Citrus indica and C. macroptera are the wild endangered species of Citrus occurring in northeastern India. Surveys were undertaken in this region for ascertaining distribution, studying variability and for collection of germplasm of these two species. C. indica, an endemic species of this region, was collected from the Citrus Gene Sanctuary located in buffer zone of Nokrek Biosphere Reserve in the Garo hills of Meghalaya. In addition, a putative natural hybrid of C. indica and C. limon was collected for the first time from the south Garo hills. C. macroptera had much wider distribution and was collected from Mizoram and Meghalaya states. In Jantia hills of Meghalaya, natural populations of this species are in a highly threatened state. The two species were unevenly distributed all over the explored territory. Morphological characterization of leaves, fruits and seeds indicated the presence of sizable variability within collected accessions of these two Citrus species. Indigenous technical knowledge gathered on the use and socio-economic importance indicated commercial potential for these two species in northeastern India. However, lack of cultivation of these species and clearing of forest cover at an alarming rate has led to an urgent need to adopt complementary conservation strategies to safeguard these species and to ensure their availability for future utilization. A major emphasis on developing methods for their propagation, multiplication and regeneration in in situ and ex situ conditions is required.     

河北省杂交棉产量构成因素研究

为了更高效地进行杂交棉品种选育,利用2006~2015年近10 a的河北省棉花区域试验资料,采用相关分析和多元逐步回归分析的统计方法,对影响杂交棉产量的构成因素进行了分析。相关分析结果表明:4个产量构成因素中,皮棉产量与单铃重呈极显著的正相关,与衣分和单株铃数呈不显著的正相关,与子指呈不显著相关;多元线性回归、偏相关分析和通径分析结果表明,4个产量构成因素均对皮棉产量有一定意义,对皮棉产量的贡献度顺序为单铃重衣分单株铃数子指。因此,在杂交棉品种选育时,应尽力提高杂交棉的单铃重,同时重视协调与衣分和单株铃数的相互关系,从而大大提高棉花的皮棉产量。     

杂交大豆昆虫传粉及制种技术研究进展

经过科学家的共同努力,吉林省农科院于2002年审定了世界上第1个大豆杂交种杂交豆1号,并于2006年审定了第2个大豆杂交种。从2000年开始,在封闭及开放条件下,利用苜蓿切叶蜂、蜜蜂、花蓟马等昆虫媒体为大豆传粉,进行不育系繁育及杂交种制种技术的探讨。已经实现在网室内利用蜜蜂及切叶蜂传粉,配制大豆杂交组合和生产小批量杂交种子,不育系结实率达到55.9%～100%;开放条件下,在干旱、有灌溉条件的地区,利用蜜蜂及苜蓿切叶蜂传粉,不育系结实率达到50%～80%,制种产量获得了较理想的结果。吉林省农科院在吉林省西部及内蒙古东部干旱地区,建立了制种基地,进行了较大面积的大豆不育系扩繁及杂交种制种试验,制种技术基本成熟。     

施钾条件下杂交水稻氮磷养分吸收利用特点

对浙江省金华市郊区石门农场灌溉稻区进行连续4年定位钾肥试验,结果表明,钾素促进氮磷养分向水稻穗部的输入,故在增产的基础上,同不施钾处理比较,施钾后杂交稻氮的总吸收量增加7.1～9.3kg/hm2,利用效率提高3.7～7.1%;磷的总吸收量增加1.0～2.0kg/hm2,利用效率提高2.0～7.7%。同常规稻比较,每季杂交稻氮和磷的平均总吸收量分别高出7.6kg/hm2和1.2kg/hm2;氮和磷的利用效率平均高出3.1kg/kg和34.7kg/kg;在养分的吸收、积累以及利用效率方面表现出明显的生理优势[1]。因此,在杂交水稻的生产实践中,应相对增加钾肥的施入量,从而提高氮肥和磷肥的利用效率。     

西葫芦新品种晋西葫芦4号的选育

西葫芦新品种晋西葫芦4号是以国外西葫芦品种的分离后代经多代自交选育而成的纯合自交系D-95-2为母本,以从我国地方品种白皮西葫芦中选育的稳定自交系E-96-8为父本杂交育成的早熟一代杂交种。该品种属短蔓密植类型,极早熟;嫩瓜皮色为鲜嫩的浅绿色,带细网纹,长筒形,光泽度好;植株生长势强,雌花多,瓜码密,耐低温、弱光,丰产,抗病,667m2产量5000kg左右。适合我国北方大部分地区早春各种保护地及露地栽培。     

西瓜新品种‘豫艺新墨玉’

 ‘豫艺新墨玉’为以‘中育9号’与美国‘Black Stone’杂交后代中选育的自交系(N89) 为母本, 以从台湾引进自交系(N9224) 为父本杂交育成的西瓜新品种( F₁ ) , 适合河南、山东、安徽、江西、湖北、湖南等西瓜产区早春露地栽培。植株生长势中等, 平均单瓜质量8～10 kg, 产量可达62.5 t/hm²。果实椭圆形, 果皮黑色, 其上覆有果粉。果肉红色, 中心可溶性固形物含量11.2% , 瓤脆爽口, 汁多味甜, 风味佳。抗枯萎病, 抗逆性较强, 较耐贮运。     

应用灰色系统理论综合评价萝卜新组合

用灰色系统理论中关联度分析的基本原理和方法,对15个萝卜杂交组合10个主要农艺性状进行了综合描述,较为全面、客观地评价了参试组合的优劣.结果表明：在等权关联度排序和加权关联度排序相比的结果来看,加权关联度排序更能反映品种的多个农艺性状的实际表现;X12,X13,X14和X5加权关联度排序上均居于首要位置,农艺性状表现突出.     

Fragrance heritability in Hybrid Tea roses

Most of the Hybrid Tea roses that are sold as cut flowers are non-scented, despite the long-standing interest of the perfume industry to rose scent. In the absence of comprehensive knowledge on the genetic and biochemistry of volatile biosynthesis in roses, we decided to characterize a Hybrid Tea progeny obtained from parents that emit very different scents. First, we identified the 11 most abundant volatile compounds synthesized by the progeny, and a short review is given for each one that describes their occurrence in the genus Rosa, in the parents and the studied progeny. We have then used statistical analysis on the distribution of volatiles among individual progeny members to unveil the laws of segregation of the scent traits in this cross. As a general rule, the quantity and quality of volatile compounds was lower in the progeny members. Variations in scent quality were mostly linked to the quantity of monoterpenes that was present. Offsprings emitting a pleasant fragrance were, in practice, found to be rare.     

杂交狼尾草生育特性研究

研究了杭州生态条件下移栽杂交狼尾草的生育特性,试验表明,杂交狼尾草平均每叶展开需积温前３叶为７５．９℃、９叶至２０叶为６２．３℃;４叶１心开始分蘖;单株干物质积累高峰期出现地拔节后,茎叶粗蛋白含量随生育期而下降;重施拔节肥是高产优质的关键,根茎安全越冬应保持地温在１０℃以上。     

黄芽白与红菜薹杂种后代的细胞遗传学特征

将白菜型油菜不同栽培种‘红菜薹’和‘黄芽白’进行正反交获得杂种一代,再经过多代自交获得高世代杂种。观察杂种后代形态学特征(叶型、株高、分枝数等）、育性特征（花粉育性、自交结实率）和花粉母细胞减数分裂染色体行为特征。结果表明经过多代自交,杂种后代各性状趋于稳定,正反交杂种形态有较大差异,而高世代杂种与杂种一代相比,形态没有明显变化。杂种后代花粉育性和自交结实率都比较高,花粉可育率均达到90%以上,但与双亲相比仍然稍差。杂种后代花粉母细胞减数分裂比较正常,但仍有少数细胞出现异常染色体行为。杂种后代减数分裂终变期染色体联会主要以形成环状和棒状的二价体为主,但也形成四价体等其他染色体构型。杂种后代中平均形成二价体的数目在6.7～8.2,最多全部20条染色体形成10个二价体,其中形成环状二价体和棒状二价体的比例相差不大。除了形成二价体外,部分花粉母细胞还形成少数四价体。与亲本相比,杂种后代染色体联会出现较多的非同源联会,平均每个细胞形成二价体的数目比亲本少,而形成四价体的数目比亲本多。在减数分裂后期Ⅰ,同源染色体分开并移向细胞两极,减数分裂后期Ⅱ,染色单体分开最终形成四分体。在此过程中,绝大多细胞染色体行为正常,但有个别细胞出现后期Ⅰ染色体不均等分离,有些细胞同源染色体分开时形成染色体桥;有些细胞在减数分裂Ⅱ中期和后期出现落后染色体。此杂种后代减数分裂过程较正常,探明杂种后代的减数分裂特征可为白菜型油菜杂交育种提供理论依据。