云南引进紫花苜蓿品种的品比试验研究

在云南不同气候条件下,对国外引进的25个紫花苜蓿Medicago sativa品种的产量表现和部分品种的营养成分进行分析、总结和评价,结果表明,最优良的品种为西玛罗紫花苜蓿,其次为猎人田紫花苜蓿.旨在为云南及相似气候环境大面积种植紫花苜蓿的品种选用提供参考.     

Production of irrigated Trifolium repens L. under a cutting regime in the subtropical region of Gauteng,South Africa

Abstract

The productivity of Trifolium repens L. cv. Ladino, under irrigation in the subtropical region of Gauteng, South Africa, is unknown. The performance of T. repens was determined over five years (1981/1982 to 1985/1986), at two defoliation frequencies, four levels of nitrogen (0, 400, 800 and 1 600 kg N ha^?1 ‐ total applied over five years), and either the removal or recycling of harvested material. Frequent, compared to infrequent defoliation, resulted in higher dry matter (DM) yields from the second year onwards. Dry matter yields were positively affected by the recycling of material, compared to no recycling. A mean DM yield of 191 ha^?1 in the first year and 12 t ha^?1 in the final year, was obtained. The highest DM yields occurred during October for all years and lowest DM yields from January to March. The first and final year showed similar peaks (late October) and troughs (March till April). Crude protein (CP) content of the herbage was influenced more by frequency of defoliation than recycling of material, where the highest CP content in any year was obtained from frequent defoliation. Nitrogen fertiliser applied up to a total of 1 600 kg N ha^?1 over five years had no effect on either DM yield or crude protein content. This study has shown that T. repens could be a productive pasture for at least five years in the subtropical region of Gauteng, South Africa. Productivity and quality of T. repens were enhanced by a defoliation interval of less than five weeks and when soil high fertility was maintained by recycled plant material.     

中蜂来源的微孢子虫对意蜂工蜂的侵染性研究

为探讨中蜂来源的微孢子虫对意蜂的侵染性,本试验将纯化自中蜂的微孢子虫,以每只蜂1×105个和5×105个孢子的接种量,分别给2日、5日、8日、11日龄无微孢子虫感染的意蜂成年工蜂接种,在30℃±0.5℃,65%～80%RH,黑暗中隔离饲养10日后,各日龄工蜂的平均感染率达86.3%～100%,每只蜂中肠的平均产孢量为5.60×105～3.39×106个。在两接种量下,2日、5日龄意蜂工蜂的产孢量均显著(P<0.05)高于8日、11日龄的产孢量。试验首次证实了中蜂来源的微孢子虫对意蜂成年工蜂具较强的侵染性。     

北大营示范场黑麦草引种与品比试验研究

利用1998年2－11月在云南省北大营示范场引种的10个黑麦草品种的观测资料，统计分析了在高、中、低3种施肥水平下黑麦草的累计产量、月平均产量及其生长速度的变化规律，研究了影响产量的主导因子及其监测模型。结果表明，在10个品种中，伯生（Bison Intermdiate）及安巴瑟（Embassy）具有良好的生产性能。黑麦草产量主要受气候、土壤肥力及品种等因素的影响，其中测草盘高度、降水量、蒸发量、日照时数和牧草生长天数等5个因子，可以较好地模拟、评估黑麦草产量的变化动态。     

Influence of feeding Tinospora cordifolia peripartum on lactation parameters in crossbred cows

For studying the effect of dietary supplementation of guduchi (Tinospora cordifolia) peripartum on lactation an investigation was conducted on 15 pregnant Karan Fries crossbred cows which were divided into two groups: treatment group of eight cows which were supplemented with guduchi at 60 g/day for 45 days prepartum and 120 g/day for 45 days postpartum; control group of seven pregnant cows which were not supplemented with guduchi. Jugular blood samples were collected from all cows during the periparturient period for analysis of various blood cell and plasma parameters. A significantly higher total leukocyte count, lymphocyte count, neutrophil count and neutrophil/lymphocyte ratio was recorded in the guduchi supplemented treatment group in comparison to untreated control cows throughout the experimental period. The increase of milk production over 305 days of lactation due to guduchi supplementation was significant (p < 0.05). A significant (p < 0.05) reduction in somatic cell count was also observed during the experimental period. Milk composition (fat, protein, lactose and SNF) was similar (p > 0.05) for both the groups. Plasma non esterified fatty acid (NEFA) concentrations were significantly higher (p < 0.01) in cows supplemented with guduchi throughout the course of study. Plasma concentration of growth hormone in the treated cows was also significantly higher beginning on the day of parturition up to 3 weeks postpartum (p < 0.05) in comparison to unsupplemented group.     

纳罗克非洲狗尾草种子产量因子与产量的通径分析

采用多因素裂区试验设计,通过大样本相关、通径和逐步回归分析后,结果表明,纳罗克非洲狗尾草Setaria sphacelata cv. Narok的6个种子产量因子对种子产量的直接贡献大小排序为：x4（单位长度小花数）>x6（千粒重）>x1（花序长）>x2（单位面积生殖枝数）>x3（单位长度小穗数）>x5（单位长度种子数）,说明提高单位长度小花数、千粒重和花序长是最有效提高纳罗克非洲狗尾草种子产量的途径,其次提高单位长度小穗数、单位长度小花数和单位面积生殖枝数。     

不同品种类型玉米不同器官和全株生物产量比较

本试验旨在比较不同品种类型玉米(Zea mays)不同器官和全株的生物产量,以提高玉米定向培育的选择效率。选择32种具有代表性的玉米优良品种为试验材料,根据淀粉性质、籽实外形、成熟性质和用途4种分类方法,分别对完熟期玉米的籽实、玉米芯、苞叶、叶片、叶鞘、茎秆及全株的鲜物质、风干物质、干物质以及粗蛋白质和总能产量进行比较。每个品种选择5个地块,每个地块选取10株玉米。结果表明:玉米的籽实、玉米芯、苞叶、叶片、叶鞘、茎秆和全株的鲜物质、风干物质、干物质、粗蛋白质和总能产量不同品种类型间差异均显著(P0.05)。根据淀粉性质、籽实外形和成熟性质分类不足以区别不同品种类型玉米的不同器官和全株生物产量(P0.05)。按用途分类,不同品种类型玉米不同器官和全株生物产量(玉米籽实的风干物质、干物质和总能产量除外)均差异显著(P0.05),表现为饲用玉米红粒玉米普通玉米糯玉米。对广泛种植的普通玉米和饲用玉米进行比较,设定普通玉米产量为100.0%,则饲用玉米籽实、玉米芯、苞叶、叶片、叶鞘、茎秆和全株的鲜物质产量分别为121.9%、164.2%、175.5%、149.0%、151.7%、168.8%和149.9%;风干物质产量分别为107.9%、143.7%、155.1%、139.4%、126.1%、162.0%和129.1%;干物质产量分别为107.5%、143.4%、155.0%、139.5%、125.7%、162.0%和129.21%;粗蛋白质产量分别为119.0%、142.9%、181.5%、161.6%、122.0%、137.4%和131.7%;总能产量分别为107.7%、143.8%、155.0%、139.4%、126.1%、162.0%和129.1%。玉米籽实干物质、粗蛋白质和总能产量占玉米全株的比例,普通玉米分别为47.75%、57.87%和48.49%,饲用玉米分别为39.72%、52.36%和40.48%。由此得出,普通玉米全株饲喂是"粮改饲"的最基本的策略,而饲用玉米籽实和全株生物产量都高于普通玉米,种植饲用玉米可以增加30%左右的土地利用。     

不同播期夏播小豆产量性能动态指标与光温水效应

为探讨光、温、水等气象因子对夏播小豆产量的影响,达到合理利用气象资源、进一步挖掘小豆增产潜力的目的,以中晚熟小豆品种花小豆(V1)和中早熟品系德红5261(V2)为材料,设T1(6月17日)、T2(6月22日)、T3(6月27日)、T4(7月2日)和T5(7月7日)5个播期,形成不同的光、温、水生长环境,对夏播小豆产量...     

固态发酵复方中药防治奶牛乳房炎的效果及对生产性能的影响

本研究采用枯草芽胞杆菌和产朊假丝酵母按等比例制作固态发酵复方中药,并对复方中药发酵前后对奶牛乳房炎及生产性能的影响进行了对比分析.结果表明,与空白组相比,复方中药发酵前后均可显著降低奶牛乳房炎的发病率(P＜0.05),可提高牛奶的乳蛋白率(P＞0.05)和乳脂率(P＞0.05),可显著提高奶牛产奶量(P＜0.05),添加复方中药制剂组和发酵的复方中药制剂组的产奶量分别较空白组提高了0.72kg/d和2.64kg/d;经发酵后的复方中药制剂在降低奶牛乳房炎发病率、改善乳品质和增加产奶量等方面的效果均优于未发酵的复方中药制剂(即普通中药制剂);复方中药经发酵后,有利于提高中药的利用率及药理活性.     

论甘南高原生态建设与可持续发展战略

简述了甘南高原区的自然地理特点,分析了甘南高原区的主要生态环境问题及其成因;指出甘南高原的生态地位十分重要,其生态环境严重恶化的状况已直接威胁到本区域乃至黄河、长江流域社会经济的可持续发展,大力开展生态保护与生态建设已刻不容缓,提出了甘南高原区生态保护、生态建设与可持续发展的对策建议。