不同有机物对铁皮石斛试管苗生长发育的影响     

周江明 《勤云标准版测试》2005,(5)

研究不同有机物浸提液对铁皮石斛试管苗生长的影响。在相同的培养条件下，以8种含有不同有机物的培养基培养试管苗，60d后对试管苗的各种性状进行记录统计，并与对照（没加有机物提取液）进行比较分析。结果不同的有机物浸提液对试管苗的影响效果不一样。壮苗以加入白萝卜提取液、CH和CM为佳，生根以加入香蕉提取液为佳，要提高繁殖系数以不加有机物为佳。  相似文献   

覆盖免耕在休闲期的节水和生育期的调温效应   总被引：10，自引：2，他引：8  

姚宝林  景明  施炯林 《甘肃农业大学学报》2005,40(2):208-211

对免耕覆盖、秸秆还田和常规耕作在休闲期的节水效果研究表明:在夏季休闲期,免耕覆盖比常规耕作多贮水30.62mm,比秸秆还田多23.91mm;在冬季储水灌溉期间,可将储水定额从2100m3/hm2减少到600和975m3/hm2。对春小麦生育期土壤表层,5、10、15、20和25cm处温度变化观测发现:免耕覆盖土壤温度在气温较低的8:00可以提高土壤表层温度,在气温较高的14:00可以减缓土壤温度的升高,而在19:00气温降低时可以减缓土壤温度的降低,使土壤温度一直保持在一个稳定的状态,这有利于调节农田小气候,创造作物良好的生长环境。  相似文献   

溴隐停对惠州麻肉种鸡产蛋性能的影响     

黄炎坤  程璞  王娟娟  司玉亭 《勤云标准版测试》2006,(12)

研究目的在于探讨多巴胺受体激动剂(溴隐停)对地方良种肉鸡繁殖性能的影响。方法从628只28周龄健康的“惠州麻”黄羽肉种鸡群中随机选取1组鸡笼内的40鸡作为实验组,其余的作为对照组。实验组鸡群喂服溴隐停,每只鸡每天1.25mg,连用4d,停用4d后再用4d,对照组不使用。结果在4周的实验期内实验组和对照组的产蛋率分别为83.86%和69.96%;破蛋率分别为1.28%和1.69%,畸形蛋率分别为4.33%和1.19%;实验组平均每只鸡的产蛋总数比对照组多3.89个、合格种蛋数多3.26个;药物处理对平均蛋重无显著影响;使用溴隐停能够提高鸡血液中的雌激素水平。结论溴隐停能够通过抑制地方良种肉鸡体内促乳素的合成与分泌,减少抱窝现象的发生,提高其繁殖性能。  相似文献   

利用生物工程提高乳锌含量技术     

苟日升 《山西农业大学学报(自然科学版)》2005,25(3):278-279

文章利用生物转化工程原理将硫酸锌加入牛饲料间接强化牛乳进行了试验观察,效果转好。强化后牛乳无外观质量变化,乳锌经一个高峰期四周后处于稳定状态,其含量可满足婴幼儿生长发育的需要。同时,还提出了硫酸锌强化饲料的适量剂量。并就乳牛饲龄、胎次、体重、产乳期对乳锌的影响和强化方法进行了探讨分析。通过此项研究,为解决目前缨幼儿缺锌问题,开发了一个吸收率高、副作用小、安全可靠的补锌源。  相似文献   

尕海地区弃耕地土壤可溶性盐分测定     

陆家宝 《青海畜牧兽医杂志》1995,25(3):21-22

１９９０～１９９３年在柴达盆地尕海地区弃耕地进行土壤可溶性盐分测定，测定结果，该地区土壤盐分组成为氯化物－硫酸盐和硫酸盐－氯化物，大部分地区耕层盐分含量小于１０ｇ．ｋｇ＾－１，少部分盐荒地表层含盐量高达７０ｇ．ｋｇ＾－１，牧草生长季节中，土壤盐分含量最低期在６月份。  相似文献   

SS-1型声速实验仪的研制     

陶灵虎 《扬州大学学报(农业与生命科学版)》1987,(4)

本文阐述了SS—1型声速实验仪的原理、结构和测量方法。波动学和分子物理学是物理学中的重要组成部分,"声速的测量"和"Y值的测量"两个实验有助于学生对波动相位的空间分布、谐振动的合成、李萨育图、能量按自由度均分原  相似文献   

碧峰峡森林土壤性状研究   总被引：1，自引：0，他引：1  

李叔南  夏建国 《四川林业科技》1995,16(4):13-19

碧峰峡不仅是旅游景点,还是多学科研究的天然“实验室”,地处雅安亚热带区,原始森林植被保护完好,土壤垂直分布明显,地质现象复杂,也是大熊猫、金丝猴出没之地。经研究结果：土壤呈酸性,自然肥力高．经相关分析结果：土壤有机质含量和ＣＥＣ等有关理化特性的相关性,较物理性粘粒与ＣＥＣ间更加显著。  相似文献   

Preliminary results of using in vitro axillary and adventitious buds in mutation breeding of Chinese gooseberry     

Xiao-Shan Shen  Jue-Zhen Wan  Wei-Yi Luo  Xiao-Ling Ding 《Euphytica》1990,49(1):77-82

Summary Aseptically cultured shoots of Chinese gooseberry exhibited growth disorder and morphological aberrances, and some died after being exposed to sufficient gamma-ray irradiation. The death rate was dose dependant and the LD₅₀ was 80–90 Gy and 50–60 Gy respectively for cv. Hayward and clone 4. All petiole explants irradiated with gamma-ray could form calli as the control, but the rate of differentiation of adventitious shoots of the petiole explants decreased and was dependant on dose. Sensitivity of the shoot or petiole explants to gamma-ray irradiation varied with species. Gamma-ray irradiation did not deter either the 2-node segments from producing axillary shoots M₁, M₂, and M₃ or the advantitious shoots originating in the petiole explants and the M₃ shoots from forming advantitious roots. Therefore, using aseptically cultured axillary or adventitious buds for mutation breeding of Chinese gooseberry is feasible. A bacterium surviving in the explants lessened the efficiency of these two in vitro techniques in mutation breeding of Chinese gooseberry.Abbreviations IAA 3-indole acetic acid - IBA -indole butyric acid - MS Murashige & Skoog (1962)  相似文献   

The fate of fluroxypyr in the soil in an oil palm agroecosystem   总被引：1，自引：0，他引：1  

MUHAMAD HALIMAH  YEW A. TAN  BIN S. ISMAIL 《Weed Biology and Management》2005,5(4):184-189

A study on the fate of fluroxypyr in Malaysian agricultural soils was carried out under natural conditions in an oil palm plantation. Three experimental plots in the oil palm estate were selected and three types of treatments were administered, namely fluroxypyr at the recommended dosage, double the recommended rate, and the untreated control. Residues of fluroxypyr in the soil, water, and oil palm leaf were monitored at regular intervals up to 90 days after treatment (DAT). The recovery of fluroxypyr in the water and soil samples ranged from 91–102% when fortified at 1–25 p.p.b. and 91–98% when fortified at 4–50 p.p.b. The recovery from the oil palm leaf ranged from 76–114% when the oil palm leaf sample was fortified at 0.05–1.0 p.p.m. The results showed that fluroxypyr leached down to 50 cm depth at 1 DAT when the plots were treated with either dosage. However, fluroxypyr was not detected in the soil residue at 14 and 21 DAT. Fluroxypyr was not detected in the oil palm leaf samples irrespective of the rates of herbicide application or sampling intervals. The residue of fluroxypyr was detected in water from a nearby stream up to 5 DAT at levels ranging from 0.06–0.21 µg L⁻¹. This result suggests that fluroxypyr persists for a short period in the soil and water ecosystems, but not in the oil palm leaf.  相似文献   

Environmental assessment tools for the evaluation and improvement of European livestock production systems   总被引：1，自引：0，他引：1  

Niels Halberg  Hayo M.G. van der Werf  Randi Dalgaard 《Livestock Production Science》2005,96(1):33-50

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