冬小麦种质“矮孟牛”中新型小麦-黑麦复杂易位的遗传传递分析

本文利用矮孟牛中一种新型小麦-黑麦复杂易位IRS·7DS,1BL·7DL与1BL·1RS易位所构建的一套重组自交系(包括109个F6株系)和8个矮孟牛衍生品种进行了分析,结果表明在109个F6株系中,纯合复杂易位占69个,纯合1BL·1RS占36个,二者比例约2∶1,杂合类型占4个,出现频率4/109;对矮孟牛8个衍生品种的分析表明,6个品种包含来自矮孟牛的     

多叶羽扇豆种子发芽条件的研究

在不同温度条件下,对多叶羽扇豆(Lupinus polyphyllus lindl)进行发芽试验,并利用不同药剂对多叶羽扇豆的硬实种子进行处理,得出以下结论:多叶羽扇豆发芽的最适温度在20℃左右,其发芽势计算应以前5 d发芽数为标准,其硬实种子采用浓硫酸处理2～5min发芽效果最好.     

旱涝交替胁迫对水稻产量和品质的影响

以"南粳44"为试材,采用温室盆栽试验,研究了分蘖期和拔节期旱涝交替胁迫对水稻产量和品质的影响。结果表明,分蘖期旱涝交替胁迫导致水稻的有效穗数较对照显著降低了20.0%和26.3%,拔节期旱涝交替胁迫导致水稻每穗粒数较对照显著降低了28.2%和41.1%,水稻产量均显著降低。分蘖期旱涝交替胁迫使稻米的出糙率、精米率和整精米率均下降,拔节期旱涝交替胁迫提高了稻米的整精米率,分别提高3.0%和2.4%,并显著降低了垩白率和垩白度。各胁迫处理均提高了稻米直链淀粉量,分蘖期重旱轻涝胁迫使得稻米的粗蛋白量较对照显著降低了7.6%。     

Effects of dietary lysozyme levels on growth performance,intestinal morphology,non‐specific immunity and mRNA expression in weanling piglets

The aim of the present study was to determine the effect of dietary lysozyme levels on growth performance, gut health and non‐specific immunity of weanling piglets. A total of 150 weanling piglets were allocated to six treatments. The piglets were fed the same basel diet supplemented with 0, 30, 60, 90 and 120 mg/kg lysozyme as well as antibiotics for 28 days. From day 14 to day 28 of dietary treatment, piglets fed 90 mg/kg lysozyme had greater average daily gain than piglets fed control diet. During the whole experimental period, piglets fed 120 mg/kg lysozyme tended to have greater average daily gain than piglets fed control diet. Compared with piglets fed control diet, piglets fed diets containing antibiotics and 90 mg/kg lysozyme had greater villus height to crypt depth ratio in duodenum and jejunum. Additionally, dietary supplementation of 60 and 90 mg/kg lysozyme as well as antibiotics enhanced the phagocytic activity of peritoneal macrophages in piglets. In conclusion, dietary lysozyme can accelerate the growth of weanling piglets by improving gut health and non‐specific immunity and supplementing 90 mg/kg lysozyme is as effective as antibiotics (20 mg/kg colistin sulphate + 50 mg/kg kitasamycin) in improving the growth performance of weanling piglets.     

The effect of lactic acid bacterial starter culture and chemical additives on wilted rice straw silage

Lactic acid bacteria (LAB) are suitable for rice straw silage fermentation, but have been studied rarely, and rice straw as raw material for ensiling is difficult because of its disadvantages, such as low nutrition for microbial activities and low abundances of natural populations of LAB. So we investigated the effect of application of LAB and chemical additives on the fermentation quality and microbial community of wilted rice straw silage. Treatment with chemical additives increased the concentrations of crude protein (CP), water soluble carbohydrate (WSC), acetic acid and lactic acid, reduced the concentrations of acid detergent fiber (ADF) and neutral detergent fiber (NDF), but did not effectively inhibit the growth of spoilage organisms. Inoculation with LABs did not improve the nutritional value of the silage because of poor growth of LABs in wilted rice straw. Inoculation with LAB and addition of chemical materials improved the quality of silage similar to the effects of addition of chemical materials alone. Growth of aerobic and facultatively anaerobic bacteria was inhibited by this mixed treatment and the LAB gradually dominated the microbial community. In summary, the fermentation quality of wilted rice straw silage had improved by addition of LAB and chemical materials.     

小菜蛾响应60Co-γ辐照的实验室种群生命表

为明确⁶⁰Co-γ亚不育剂量辐照对小菜蛾Plutella xylostella种群数量动态变化的影响,构建小菜蛾种群动态变化模型,在实验室条件下通过建立小菜蛾生命表获得种群特征参数、个体生理指标,预测亚不育剂量辐照对小菜蛾种群的影响。结果显示,亚不育剂量辐照组的羽化率显著高于完全不育剂量组,与空白对照组无显著差异,各处理羽化率无性别差异,亚不育剂量辐照组F1代孵化率显著低于空白对照组。亚不育剂量辐照组种群各阶段发育历期、存活率及繁殖力生命指标低于空白对照组。小菜蛾亚不育剂量辐照组世代平均历期(19.90 d)、世代净生殖率(2.35)、周限增长率(1.04 d-1)、内禀增长率(0.04 d-1)均低于空白对照组,而种群加倍时间(16.16 d)高于空白对照组。空白对照组世代平均历期、每日单雌产卵量与产卵时间均长于亚不育剂量辐照组。辐照组与对照组种群生命表参数对比,表明亚不育剂量降低了小菜蛾种群世代数和幼虫期的个体存活率,使F1代雌虫个体数减少。     

励磁功率单元主回路快速故障诊断策略

分析总结了发电机组励磁系统功率单元的故障类型和常见故障,通过Matlab仿真功率单元主回路故障类型,重点研究基于故障频谱分析的定量故障特征提取和故障分类,提出了一种快速针对功率单元主回路的故障诊断真值表法,最后通过实验平台验证故障类别,结果表明：该方法能够正确有效地诊断出功率单元主回路具体的故障晶闸管,为励磁系统功率单元故障诊断提供依据。