施肥水平及群体结构对茄子单株和群体效应的影响

研究了不同施肥水平及种植密度对茄子单株和群体效应的影响,结果表明:单株产量随着密度的增加而减少.密度对群体产量的影响与施肥水平有关.在低肥时,密度应小,高肥时可适当提高密度,品种才能获得高产稳产.随着密度的逐步降低,个体补偿效应和群体补偿效应下降,施肥水平越高,补偿效应下降越明显.     

棉田棉铃早着卵株率和百株卵量关系模型的建立与应用

通过调查研究建立安徽两大棉区棉田不同世代棉铃虫着卵株率和百株卵量关系方程,并对方程的准确性和应用该抽样方法的工效进行了检验与比较,认为该方法是一种有效的估值手段。     

Conductivity and photoconductivity in egg white

Activation energies of 1.47 to 2.94 electron volts were obtained in egg white. These values are too large to be consistent with the large observed currents if one uses a semiconductor model and indicate that the standard semiconductor model is inappropriate for this biological material.     

Bag cell control of egg laying in freely behaving aplysia

Neuroendocrine (bag cell) control of egg laying was studied in freely behaving Aplysia. Surgical lesions showed that bag cells are not necessary for egg laying, although they play a crucial role in its control, and that the pleurovisceral connectives are the afferent pathway to the bag cells. Recording in vivo showed that synchronous bag cell spikes progressively invade the network, leading to prolonged repetitive firing that initiates natural egg laying.     

Rapid evolution of egg size in captive salmon

Captive breeding and release programs, widely used to supplement populations of declining species, minimize juvenile mortality to achieve rapid population growth. However, raising animals in benign environments may promote traits that are adaptive in captivity but maladaptive in nature. In chinook salmon, hatchery rearing relaxes natural selection favoring large eggs, allowing fecundity selection to drive exceptionally rapid evolution of small eggs. Trends toward small eggs are also evident in natural populations heavily supplemented by hatcheries, but not in minimally supplemented populations. Unintentional selection in captivity can lead to rapid changes in critical life-history traits that may reduce the success of supplementation or reintroduction programs.     

Marine fish egg hydration is aquaporin-mediated

The positive buoyancy of marine fish eggs in sea water, allowed by hydration of the oocyte, is critical for their survival and dispersion in the ocean. We isolated an aquaporin, SaAQP1o, that belongs to a unique subfamily of aquaporin-1-like channels specifically evolved in teleosts and mainly expressed in the ovary. We further show that hormone-induced fish oocyte hydration is a highly controlled process based on the interplay between protein hydrolysis and the translocation of SaAQP1o to the plasma membrane, indicating a specialized physiological role for this aquaporin.     

肉鸭种蛋重与蛋形指数对孵化效果的影响

将肉鸭种蛋按蛋重、蛋形指数大小各分为5组,在相同条件下孵化.结果表明,蛋重、蛋形指数对受精率和早期死胚率无显著影响(P>0.05),蛋重为85.5～100.6g(D,E)组、蛋形指数为1.15～1.25(F)和1.59～1.69(J)组中后期死胚率显著升高;蛋重为75.3～85.4g时,受精蛋孵化率和入孵蛋孵化率最高,分别为91.4%～95.7%和85.3%～89.3%;蛋形指数为1.26～1.47时,受精蛋孵化率和入孵蛋孵化率最高,分别为90.9%～97.2%和86.7%～93.3%.     

人胎盘碱性磷酸酯酶基因在鸡蛋蛋清中的表达

利用PCR方法从pSEAP2-control质粒中扩增获得人胎盘碱性磷酸酯酶基因plap的cDNA,将其克隆到鸡输卵管特异性表达载体(pAB-Sig-SV40)的卵清蛋白基因调控区下游。通过脂质体精子载体法人工授精母鸡,收集鸡蛋、孵化。雏鸡出壳后,抽提鸡冠基因组DNA,采用PCR方法检测两组孵化后代中的嵌合体鸡,第1组母鸡(95羽)中plap的PCR阳性检出率为75%,第2组母鸡(128羽)的阳性检出性率为81%。经Western blotting检测,仅1只嵌合体母鸡所产鸡蛋蛋清中检测到plap产物的存在。     

饲粮蛋白质水平对鹌鹑产蛋性能和蛋品质的影响

采用单因子试验设计,将饲粮粗蛋白质(CP)设为6个水平,分别为16％、18％、20％、22％、24％、26％,将鹌鹑分为相应6个组,每组4个重复,每个重复20只鹌鹑,试验分2期进行,前期为6～33周龄,后期为34～41周龄,研究饲粮中蛋白质水平对产蛋鹌鹑产蛋性能和蛋品质的影响.结果表明:第1组鹌鹑后期产蛋量显著低于第2...     

中国洁蛋生产与消费的重要性及关键加工技术

综述了中国洁蛋生产消费的重要性研究进展,分析了洁蛋生产的现状及国外的生产情况,详细介绍了中国带壳鲜蛋的清洗、消毒、干燥、分级、涂膜保鲜等一系列的加工技术.     

Changes in soluble citrate of pigeon bone during egg laying

Accompanying the structural changes in medullary bone during the egg-laying cycle there are local increases in the concentration of soluble, citrate. Since citrate can form both soluble and insoluble compounds with calcium, it is suggested that this anion may have a regulatory function in bone apposition and resorption.     

微机自控禽蛋孵化厅的研究

大、中型孵化厅是由数个孵化间（箱）组成，我们以廉价的８倍微处理器Ｚ—８０ＣＰＵ为控制核心，以自行开发的ＦＴ—８０ＤＢＧ实时多任务操作系统为环境，结合控制盆上动态实时参数显示（各厅温度、湿度等）及各种状态显示（蛋架位置、报警信号等），可按要求通过打印机自动打印孵化报告。所以，在控制室可随时准确地了解到各个孵化间中不同类型禽蛋在不同孵化期的孵化情况，该设备具有操作简便，性能价格比高等优点。     

New advances in the science and use of Trichoderma spp.

Trichoderma spp. have been known for their strong abilities to produce extracellular enzymes, especially cellulases and glucanases by T. reesei, and also for their abilities to control plant pathogens. Most notably, a number of lines of evidence indicate that the agriculturally relevant strains are synergistic plant symbionts. As plant symbionts they possess the following characteristics: (a) they infect plant roots but cause the plant to restrict their growth to outer layers of the plant co…     

Unique envelope of a jellyfish ovum: the armed egg

The eggs of Bougainvillia multitentaculata are spawned with an envelope consisting of a single layer of cnidocvtes. The cnidocytes are surficial On eggs, cleavage stages, and young blastulae. During gastrulation, the cnidocytes are Incorporated intO the ectoderm and become an integral part of the planula.     

Reduced egg investment can conceal helper effects in cooperatively breeding birds

Cooperative breeding systems are characterized by nonbreeding helpers that assist breeders in offspring care. However, the benefits to offspring of being fed by parents and helpers in cooperatively breeding birds can be difficult to detect. We offer experimental evidence that helper effects can be obscured by an undocumented maternal tactic. In superb fairy-wrens (Malurus cyaneus), mothers breeding in the presence of helpers lay smaller eggs of lower nutritional content that produce lighter chicks, as compared with those laying eggs in the absence of helpers. Helpers compensate fully for such reductions in investment and allow mothers to benefit through increased survival to the next breeding season. We suggest that failure to consider maternal egg-investment strategies can lead to underestimation of the force of selection acting on helping in avian cooperative breeders.     

Nitrogen fertilizer recommendations based on plant sensing and Bayesian updating

Methods are available to predict nitrogen needs of winter wheat based on plant sensing, but adoption rates by producers are low. Current algorithms that provide nitrogen recommendations based on plant sensing implicitly assume that parameters are estimated without error. A Bayesian updating method was developed that can incorporate precision plant sensing information and is simple enough that it could be computed on-the-go. The method can consider producers prior information and can account for parameter uncertainty. Bayesian updating gives higher nitrogen recommendations than plant sensing recommendations using a plug-in method. These recommendations increase net returns over the previous recommendations, but not enough to make plant sensing profitable in this scenario.     

Active remodeling of somatic nuclei in egg cytoplasm by the nucleosomal ATPase ISWI

Cloning by the transplantation of somatic nuclei into unfertilized eggs requires a dramatic remodeling of chromosomal architecture. Many proteins are specifically lost from nuclei, and others are taken up from the egg cytoplasm. Recreating this exchange in vitro, we identified the chromatin-remodeling nucleosomal adenosine triphosphatase (ATPase) ISWI as a key molecule in this process. ISWI actively erases the TATA binding protein from association with the nuclear matrix. Defining the biochemistry of global nuclear remodeling may facilitate the efficiency of cloning and other dedifferentiation events that establish new stem cell lineages.     

城市道路植物景观综合评价模型构建与应用

为客观评价城市道路植物景观现状,选择9个重要评价因子,采用层次分析法,建立城市道路植物景观综合评价模型,并以杭州市14条具有代表性的主干道路绿地为对象进行研究.结果表明:植物物种多样性、植物景观空间构成、植物生活型结构多样性及植物景观地域特色是影响城市道路植物景观质量的主要因子;杭州市白沙路、白堤、之江路的植物景观综合...     

野生大豆G.soja主要性状的遗传参数

本文研究了一年生野生大豆 G.soja 的单株荚数、荚重、粒数、粒重、分枝数、秆干重、株高、百粒重8个数量性状的遗传参数。结果表明:各性状不同类型间F 值达显著或极显著,遗传变异系数较大,遗传力普遍较低,各性状间的遗传相关大部分呈密切的正相关,影响单株籽粒产量的主要因素是单株粒数。     

Biochemical approach to predicting chicken egg productivity

Injection of 17β-estradiol into chicks in a dose of 20 mg/kg increases the content of total protein, triglycerides, total calcium, and inorganic and protein phosphorus in blood plasma. A linear relation is found between the content of the phosphoprotein phosphorus and total calcium. It is suggested to use the total calcium level in blood instead of phosphorus when predicting chicken egg productivity as a simpler index in a methodological respect.