Risk Factors for Kid Mortality in West African Dwarf Goats Under an Intensive Management System in Ghana

Breeding records from 1997 to 2000 for West African Dwarf goats kept under an intensive management system on the National Breeding Station at Kintampo in Ghana were analysed for the effect on mortality of sex, season and type of birth, and birth weight. The pre-weaning and post-weaning mortalities were 10% (n = 390) and 23.1% (n = 351), respectively, while the overall mortality from birth up to 12 months of age was 30.8% (n = 390). The post-weaning period recorded significantly higher proportions of deaths in males, females, single-born and twins, during the rainy and dry seasons, and for kids with low or high birth weight, compared to the pre-weaning period. There was significantly higher mortality in male kids than in female kids. The odds and risks of death for male kids were about twice those for females at post-weaning and up to 1 year of age. At pre-weaning and up to 1 year of age, a higher proportion of the dead were twins. Twins had approximately 2.5 the risk of death at pre-weaning, compared to singles. Also, kids born in the rainy season had significantly higher mortality than those born in the dry season. Kids that died by the time of weaning were significantly lighter in weight at birth than those that survived. Male kids had significantly higher mean weights at birth and at weaning, but not at 12 months of age. The significance of these findings is discussed.     

Morphology of papaya plants derived via anther culture

This study was set up to investigate the morphological and fruiting characteristics of anther derived triploid papaya and evaluate their usefulness in commercial fruit production and breeding. A commercial diploid dwarf cultivar, ‘Wonder blight’ and 26 anther derived papaya strains were raised in the same green house. Data were collected on their morphological and fruiting characteristics like trunk height, fruiting height and the sizes of leaves, flowers and fruits. The anther derived papaya strains were variable in height and could be classified into dwarf, semi dwarf and tall. All the anther derived papaya strains bore only female flowers and produced fruits parthenocarpically. Parthenocarpic ability was variable among the strains. The dwarf and semi dwarf strains were fewer than the tall strains and they had good bearing and high yield of fruits. Two dwarf strains particularly produced parthenocarpic fruits that weighed an average of 670.0 and 871.3 g, compared to the diploid cultivar, ‘Wonder blight’, whose fruits weighed 696.4 g. The combination of short stature with a high yield of large fruits means that these strains have a lot of potential for exploitation in both breeding and commercial fruit production.     

矮化杏新品种‘金矮杏’

 金矮杏’是‘金太阳杏’的变异品种。树体矮小紧凑，枝条节间短，叶片小而厚，果实圆形，平均单果质量56.9 g，果皮底色橙黄，果肉黄色，可溶性固形物含量14%，多汁，酸甜可口,离核，仁苦。自花结实率高，连续结果能力强，丰产，适合山西省杏产区保护地密植栽培和制作观赏盆景。     

苹果矮化砧木SH_(40)和M_(26)铁吸收动力学参数比较

以苹果矮化砧木SH40、M26的生根试管苗为试材,采用水培方法,研究了根系铁离子吸收动力学特性。结果表明,苹果砧木幼苗对铁离子的吸收均符合Michaelis-Menten离子吸收动力学规律。除砧木类型外,铁离子吸收速率还受到介质供铁水平、处理时间、介质温度的影响。随着介质供铁水平的升高砧木铁离子吸收速率逐渐升高,与SH40相比,M26对铁有较强的吸收能力;温度升高铁离子吸收速率增强,处理时间越长铁离子吸收速率越低,在0-1h吸收速率最高。     

花粉管通道法介导的抗大麦黄矮病毒转基因小麦研究

构建了大麦黄矮病毒GPV株系串联结构复制酶基因植物表达载体pPPI29,通过花粉管通道法转化了CA8686小麦,对T₀代种子进行了分子检测,获得6株转基因小麦,转化率达到0.45%;对获得的T0代转基因小麦进行了田间抗病性鉴定,结果表明4株转基因小麦对GPV株系表现为高抗,可以推迟发病23 d。     

甜樱桃矮化砧木新品种‘吉塞拉5号’

 甜樱桃矮化砧木‘吉塞拉5号’具有矮化、丰产、早实性强、抗病、耐涝、土壤适应范围广、抗寒等优良特性。‘吉塞拉5号’的引进及推广利用, 有利于克服我国甜樱桃生产的树体高大、难于管理等问题。     

狗牙根的组织培养及其矮化变异体研究初报

 以杂交狗牙根品种‘Tifeagle’的匍匐茎节作外植体，诱导出胚性愈伤组织，进一步分化后获得了再生植株。在再生植株中出现了体细胞变异，其中一株TV4的匍匐茎节间长度比亲本减短了47％，叶长减短了32％，叶宽增大了30％，根系较亲本更发达，耐冷性略高于亲本。     

矮砧苹果集约栽培水肥一体化技术应用及研究

为了探究水肥一体化技术对矮砧苹果栽培的应用,进一步推进矮砧苹果基地高质高效发展进程,从国内外研究进展技术及设备系统配套进行了阐述,结合实际,深入分析了水肥一体化对矮砧苹果栽培肥料利用率、产量、品质等方面应用效果,对水肥一体化技术应用推广过程中存在的成本高、易堵塞、易积盐和限根生长问题进行研究探讨,提出了加强水溶肥产品研发推广、加强设备开发与技术示范、加强管护支持力度三个方面的路径策略,并对水肥一体化技术推广前景进行了展望。     

梨矮化砧木新品种‘中矮2号’

 ‘中矮2号’是采用有性杂交技术选育而成的梨矮化砧木品种, 作梨树中间砧木或自根砧木具有促进嫁接品种树矮化、早果、早期丰产、果实品质好等特点。砧木品种本身抗寒性强, 高抗梨树枝干轮纹病或枝干腐烂病。     

Growth promotion by sodium in amaranthaceous plants

The amaranthaceous dwarf glasswort, Swiss chard, table beet, spinach and Mexican tea were grown in solutions containing 0, 20, 40, 80, 120, 160, 180 and 200 mol m^?3 sodium chloride (NaCl). Maximum growth and increase of biomass production compared to that at 0 mol m^?3 of dwarf glasswort was observed at 200 mol m^?3 (245%), and Swiss chard (146%), table beet (128%) and spinach (138%) at 80 mol m^?3. The growth of these species increased with increasing sodium (Na) concentration of shoot until it reached 4.18, 2.42, 1.60 and 1.58 mol kg^?1, respectively. These indicate that the order of Na-loving character is dwarf glasswort >> Swiss chard > table beet = spinach. The water contents increased with increasing Na concentration until growth reached maximum in dwarf glasswort and Swiss chard. In these highly Na-loving species, Na is activity transported to shoots and utilized for producing osmotic pressure to absorb water.