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1.
The plants of field bean var. Nadwiślaνski were detopped after about 1 month since the beginning of flowering and after that all flower buds were removed from some plants. The effect of a change in the trophic balance on the setting and subsequent growth of root nodules was studied.
The removal of pods had the greater effect on the increase in the weight of the remaining organs than the detopping of plants. Detopping retarded the ageing of the plants and delayed the phase of the greatest reduction of the number of pods. The detopping of plants revealed their considerable compensative possibilities in terms of production of the pod weight and the potential of leaves for biomass production. The data obtained indicate that plant detopping may disturb the root–bacteria exchange of signals, necessary to initiate the nodule development, while the further growth of nodules depends, above all, on the amount of available photosynthates.
A very high correlation between the dry weight of the whole plant to the dry weight of leaves ratio and the weight of nodules was observed. It proves the importance of the trophic balance of the plant for the root nodule weight production.  相似文献   
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Abstract. The repeated application of pig slurry to agricultural soils may result in an accumulation of salts and a risk of aquifer pollution due to nitrate leaching and salinization. Under Mediterranean conditions, a field experiment on a sandy loam soil (Typic Xerofluvent) was performed with maize (Zea mays) in 1998, 1999 and 2001 to study the effects of applying optimal (P1) and excessive rates (P3) of pig slurry on soil salinization, nitrate leaching and groundwater pollution. The rate of pig slurry was established considering the optimal N rate for maize in this soil (170, 162 and 176 kg N ha?1 for 1998, 1999 and 2001, respectively). Pig slurry treatments were compared to an optimal N rate supplied as urea (U) and a control treatment without N fertilizer (P0). The composition of the slurries showed great variability between years. Mean NO3? leaching losses from 1998 to 2001 were 329, 215, 173 and 78 kg N ha?1 for P3, P1, U and P0 treatments, respectively. The amount of total dissolved salts (TDS) added to the soil in slurry application between 1998 and 2001 was 2019 kg TDS ha?1 for the P1 treatment and 6058 kg TDS ha?1 for the P3 treatment. As a consequence, the electrical conductivity (EC) of the slurry‐treated soils was greater than that of the control soil. The EC correlated significantly with the sodium concentration of the soil solution. Over the entire experimental period, 2653, 2202 and 2110 kg Na ha?1 entered the aquifer from the P3, P1 and P0 treatments, respectively. The P3 treatment did not significantly increase grain production in 1999 and 2001 compared with that achieved with the optimal N rate treatment (P1). This behaviour shows the importance of establishing application guidelines for pig slurry that will reduce the risk of soil and groundwater pollution.  相似文献   
4.
杨学 《中国麻业》2004,26(5):225-227
从亚麻细菌病的发生、发展、危害及病原茵特性到病害综合防治,进行了系统研究,明确了该病的发生与品种抗性、耕作栽培等诸方面的关系,为病害防治提供了理论依据;明确了种子带茵是该病害主要侵染源和传播途径,同时建立综合防病体系。  相似文献   
5.
通过对哺乳仔猪群、保育群、育成群各月死亡率的统计分析发现,冬季低温对哺乳仔猪群、保育群死亡率的影响远远大于夏季高温的影响。冬季低温对保育群的死亡率影响最大,而对育成群几乎没有影响。夏季高温对不同猪群的死亡率有不同程度的影响力。不同猪群对温度反应的快慢、强度及持续期各不相同。  相似文献   
6.
李明丽  鲁绍雄 《家畜生态》2004,25(4):241-244
猪胚胎死亡直接影响着母猪的产仔数,并进而影响着养猪生产的经济效益。因此,在深入研究猪胚胎死亡规律及其影响因素的基础上,通过有效的措施降低胚胎死亡率,对提高母猪窝产仔数和经济效益具有十分重要的意义。本文综述了影响猪胚胎死亡的遗传、环境、营养和疾病等因素,并对生产实践中如何通过综合预防措施降低猪胚胎死亡率进行了初步探讨。  相似文献   
7.
采取新鲜血液压片相衬观察和末梢血液涂片染色镜检法,对河南省新乡地区3000头猪附红细胞体病发病情况进行了调查;并且对体温升高、镜检附红细胞体感染强度为 病猪的血液,分别用光学显微镜、扫描电子显微镜进行形态观察和血液生化指标检测.结果表明:猪附红细胞体病的发病率为46.33%,死亡率为13.88%,隐性感染率为55.93%(755/1350).在光学显微镜下观察,红细胞呈现菠萝样;染色血片观察附红体在红细胞表面及边缘呈各种形式排列,可见强折光性发亮的圆形小体;扫描电子显微镜观察.附红体寄生的红细胞凹陷区,有大、小球体,有的小球体与大球体相连.血清胆红素、白蛋白、尿素氮、谷丙转氨酶、谷草转氨酶增加,血糖、血清总蛋白、超氧化物歧化酶活性下降.  相似文献   
8.
采用PCR-RFLP-ApaⅠ方法检测高坡猪GH基因-119~ 486 bp片段的多态性,探讨了不同基因型对其部分生产性能的影响。结果表明:产生2个等位基因A(449 bp)和B(316 133 bp),其频率分别为0.54和0.46;3种基因型:AA、AB和BB,其频率分别为0.26、0.56和0.18;除6月龄腹围和背膘厚外,其余指标值均以BB基因型最高,AA基因型的6月龄腹围和瘦肉率与BB基因型相比差异显著(P<0.05),其他指标在各基因型间差异均不显著(P>0.05)。表明,A可能是小型猪的有利等位基因,B则可能是大型猪的有利等位基因。  相似文献   
9.
为探究不同氨基酸菌肥施用量对茶树生长和土壤肥力含量的影响,以鸿雁12号茶树为研究对象,采用田间微区试验的方法,设置了不施用氨基酸菌肥作对照组(CK)和氨基酸菌肥施用量分别为75 kg·hm-2(T1)、150 kg·hm-2(T2)、225 kg·hm-2(T3)和300 kg·hm-2(T4)的处理,研究不同氨基酸菌肥施用量对茶树生长、茶叶品质及土壤肥力的影响。结果表明:氨基酸菌肥施用后能显著增加茶叶芽头密度及茶叶产量,提高茶叶中氨基酸含量和土壤中碱解氮含量。试验6个月后与CK相比,T4组的芽头密度显著增加了63.4%,茶叶产量显著增加了71.5%;T1~T4处理茶叶中氨基酸含量分别增加了9.73%、6.41%、7.57%和13.2%,土壤中碱解氮含量分别增加了25.0%、36.0%、46.0%和37.6%。综上,氨基酸菌肥的施用能提高茶叶产量及品质,改善茶园土壤环境质量,为茶园生产的合理施肥及优质高效生产提供数据参考。  相似文献   
10.
This review is devoted to the study of the biological activity of polyether ionophores produced by bacteria, unicellular marine algae, red seaweeds, marine sponges, and coelenterates. Biological activities have been studied experimentally in various laboratories, as well as data obtained using QSAR (Quantitative Structure–Activity Relationships) algorithms. According to the data obtained, it was shown that polyether toxins exhibit strong antibacterial, antimicrobial, antifungal, antitumor, and other activities. Along with this, it was found that natural polyether ionophores exhibit such properties as antiparasitic, antiprotozoal, cytostatic, anti-mycoplasmal, and antieczema activities. In addition, polyethers have been found to be potential regulators of lipid metabolism or inhibitors of DNA synthesis. Further study of the mechanisms of action and the search for new polyether ionophores and their derivatives may provide more effective therapeutic natural polyether ionophores for the treatment of cancer and other diseases. For some polyether ionophores, 3D graphs are presented, which demonstrate the predicted and calculated activities. The data presented in this review will be of interest to pharmacologists, chemists, practical medicine, and the pharmaceutical industry.  相似文献   
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