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61.
为筛选SOCS6基因启动子区域单核苷酸多态性(Single nucleotide polymorphisms,SNP)并研究其对启动子功能元件的影响,选择品种差异较大的贵州荷斯坦奶牛和务川黑牛构建DNA池,直接测序筛选SNP位点.结果表明,SOCS6基因5'调控区存在4个SNP位点,分别为T-513G、C-401T、A-332G和T-180G.生物信息学软件预测得到SOCS6基因核心启动子区和CpG岛,SNP位点导致附近部分转录因子结合位点消失和新位点产生.多态性位点对转录因子结合位点有显著影响,但并不改变CpG岛大小. 相似文献
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福建省华安县茶园病虫害绿色防控措施及现状 总被引:2,自引:0,他引:2
华安县历来是福建漳州市的茶叶主产区(当前主栽品种是"红牙"铁观音,占99%以上)。近年来,全县茶叶产业迅速发展壮大,至今拥有茶园总面积15.6万亩,预计今年总产1.5万吨,产值可达15亿元。全县现有7000多家茶叶初制加工厂,100多家精制加工企业,茶叶加工、营销龙头企业30多家,茶叶营销网络遍布全国各地,转移劳动力4万多人,占全县农业总产值的65%,是我国第二大铁观音茶生产 相似文献
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It is very important to study eco-physiological processes of plants and to determine quantitative relations between accumulation, distribution of dry matter and environmental factors for regionalization, standardization and precision agriculture. Meanwhile, global changes, e.g., atmospheric CO2 concentration rising, global warming, and climate abnormity, have been effecting on agricultural productivity. This study provides a theoretical basis for predicting productive potentials and development trends in different agricultural regions. One-year-old black walnut (Juglans hindsii) seedlings were employed as subjects for setting up the dynamic models of dry matter accumulation and distribution, based on mechanistic models of photosynthesis, matter conservation and concentration gradient. Under optimum conditions of soil moisture and mineral nutrient, during the period of the canopy construction, the dry matter accumulation of the canopy conformed to logistic curves; but the accumulation of both total biornass and dry matter of stem-root could be divided into two phases: the first phase was exponential increase, the second was linear increase. The total biomass, dry matter of canopy and stem-root all presented a fluctuant increase, which was affected by the environmental factors. Ratio of daily increase of dry matter in the canopy and the steem-root (dWJdWs) was changeable along with growth periods and environmental factors. At the initial stage of the canopy forming, dW/dWs was larger, about 3.2 on average, which indicated that the photosynthetic product was mainly used to develop leaves; in the midterm, it was about 1.9, which indicated that the distribution of dry matter in the canopy and in the stem-root was relatively balanced; when the plant tended to stop growing, dWl/dWs decreased linearly, and the main distribution of dry matter moved to the roots. 相似文献
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菜黑斯象 (ListroderesobliquusKlug)又称蔬菜象鼻虫 ,属鞘翅目 ,象虫科 ,原产南美 ,近年传入我国。 2 0 0 2年春季昆明市郊区呈贡、西山、富民、石林等县 (区 )发现其危害甘蓝、白菜、青菜等十字花科作物 ,成为蔬菜产区的一种新害虫。形态特征 :成虫体 相似文献
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Based on the distribution of 64 locations in wattle natural distribution in Australia and the data collected from 61 plantations in 30 more countries, 5 important factors were selected for determining the suitable climatic requirements for the growth of wattle. The experience of plantation wattle in China for over 30 years has been summarized. According to the comparison of climate and geographic distribution of wattle in China and other countries, China is a suitable country for growing wattle. Based on the results of our investigation, a division of suitable areas for growing wattle in China was made. Key points of planting method in each area were suggested. 相似文献