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1.
Even though the respiratory system is one of the most accessible organs for diagnostic testing, it is not always easy to define chronic lower airway disease in the horse. Diagnostic procedures performed by first opinion veterinarians in the field are often restricted to taking the history and performing clinical examination. Respiratory tract endoscopy, tracheal or bronchoalveolar lavage, and blood sampling are sometimes used but other specific ancillary examinations are seldom performed in stable settings. Therefore, our objectives were to evaluate the diagnostic value of different techniques and examination types routinely used in the diagnostic workup of chronic equine lower airway cases in both stable and clinical circumstances. Another aim of this study was to estimate the prevalence of different chronic pulmonary disorders among horses admitted to a Hungarian referral clinic. According to the conditional inference tree method, age of the horse, history, clinical examination, respiratory tract endoscopy, and bronchoalveolar lavage cytology proved to be the most valuable tools to define pathology. It was also concluded that in 22% of cases, more specific ancillary diagnostic modalities, unavailable for the field veterinarian, were needed to establish the final diagnosis. According to our study, the most frequently diagnosed chronic pulmonary disorders in Hungary are of noninfectious origin, principally recurrent airway obstruction. Regardless of the cause, and interestingly including recurrent airway obstruction as well, these diseases occur primarily during the warm months.  相似文献   
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3.
Four snap bean varieties (green and yellow-podded) were grown in three water supplies (regularly irrigated, deficit-irrigated and non-irrigated) in order to examine the spectral reflectance at leaf and canopy levels, leaf area index (LAI) and their relationships with the yield and nutritional quality at the University of Debrecen, Debrecen, Hungary from 2011 to 2013. Under non-irrigated condition, the plant height decreased, SPAD values were high but LAI and normalized difference vegetation index (NDVI) were low. The difference in SPAD values was higher between the varieties during flowering under non-irrigated condition and it was more pronounced during pod development using deficit irrigation. In dry years, non-irrigated condition SPAD did not correlate with the yield but during pod development it was correlated with the dry matter content of the pods. The relationship of SPAD with protein and crude fiber content of pods was strongly dependent on the cropping years. Under deficit-irrigated condition, NDVI measured during flowering and pod development correlated closely with the yield where a higher NDVI (0.85) predicted either 6 or 9.5 t ha?1 of yield depending on the variety. Under this condition Serengeti variety with green pods was prominent based on the studied traits among the varieties.  相似文献   
4.
The 1BL.1RS wheat-rye translocation and a wheat-Triticum timopheevii chromosomal introgression carry the Sr31, Lr26, Yr9 and Pm8 genes and the Sr36/Pm6 gene cluster, respectively. The objective of this study was to determine the distribution and impact of these two translocations in 220 wheat varieties registered in Hungary in the last 35 years until 2005. The 1BL.1RS translocation was introduced into Hungary via wheat cultivars ‘Avrora’ and ‘Kavkaz’, which were registered in 1970. New 1BL.1RS cultivars developed in Hungary first appeared in 1982. After reaching a maximum frequency of 50.0% among cultivars registered in Hungary in 1994, their presence declined steadily to 13.3% by 2005. The Sr36/Pm6 cultivars first appeared in 1980. Their frequency quickly reached 31.8% (1983–1984), but then dropped to between 9.6 and 18.5% (1990–2005). The two main Hungarian breeding programs showed opposing trends in the exploitation of these two translocations. In Martonvásár, 1BL.1RS played a dominant role, being present from 1993 to 1997 in ca. 95% of the released cultivars, while at the same time the use of Sr36/Pm6 was marginal. Conversely, among the Szeged cultivars, Sr36/Pm6 was present at high frequency (44.7% in 2002) with a low share of 1BL.1RS. In artificial field inoculation tests (1985–2003) both of the stem rust resistance genes provided significant resistance in all the years, though Sr36 proved more effective than Sr31. While Pm8 was not effective, except for the last 2 years, Pm6 exhibited significant resistance against powdery mildew in most of the 18 years tested. These data may help breeders to assess the usefulness of wheat-rye 1BL.1RS chromosome translocations and the Sr36/Pm6 resistance gene clusters in their future wheat improvement programs.  相似文献   
5.
Abstract

Seedlings of four maize hybrids were grown hydroponically to investigate the impact of different N sources (Ca(NO3)2, (NH4)2SO4 and a 1:1 mixture of both) on (i) production and partitioning of root and shoot dry matter, (ii) concentration of soluble carbohydrates in roots and shoots and their partitioning to these plant parts, (iii) concentration of starch in the shoot, and (iv) N uptake. During the main phase of the experiments (duration 14d), the plants were grown in a greenhouse at 25/22°C day/night temperatures and a photoperiod of 16h. Nitrogen was supplied at three concentrations (2.8, 28, and 280 ppm). The root‐zone pH was 6.5. Under the lowest N supply, the N sources produced similar root and shoot dry matters. At the highest N level (280 ppm), NO3‐fed plants were superior. In contrast, the mixture of NH4 and NO3 ? was optimum at 28 ppm. More or less pronounced N form by N concentration interactions were also found in the concentration and distribution of soluble carbohydrates and in all remaing traits. There were almost statistically significant cultivar by N form interactions in shoot dry matter (P = 0.07) and total dry matter (P = 0.06), indicating the existence of considerable genotypic variation in sensivity to NH4‐N.  相似文献   
6.
Helianthus tuberosus agg., an herbaceous perennial plant from the Asteraceae family, is native to North America and was introduced as a crop to Europe in the seventeenth century. The status of this plant has been rather controversial in the Carpathian Basin. This paper reviews its taxonomy, chorology, and ethnobotany in this region, using data obtained from herbarium specimens, ethnobotanical surveys performed in Transylvania, and data published earlier, documenting the invasive features of the plant since the beginning of the nineteenth century. Our results suggest that (1) Helianthus tuberosus agg. has been present in the Carpathian Basin from the nineteenth century, (2) its taxonomy is problematic since the first part of the nineteenth century; (3) ethnobotanical surveys confirmed that the plant’s tuber has been locally used mostly as a food in Transylvania, collected from cultivation. Overall, Helianthus tuberosus agg. is both a ‘blessing and a curse’ at the same time, it is a valuable crop with beneficial nutritional value, and also an environmentally dangerous invasive element for the diversity of the flora of the Carpathian Basin.  相似文献   
7.
An abdominal cystic lymphangiomatosis in a Mt. Carmel blind mole rat (Nannospalax (ehrenbergi) carmeli) is described. This case was most likely due to a congenital abnormality with long-term compensation by the animal. The case describes the clinical course and subsequent postmortem examination. The death in the animal was caused by an abscess in the peritoneal wall and subsequent peritonitis.  相似文献   
8.
Two haploid induction media (190-0 and W14mi) were tested in isolated microspore culture of two triticale (X Triticosecale Wittmack) genotypes. The W14mi medium proved superior for the production of green plantlets in both genotypes. This basic medium (W14) was used to compare two doubled haploid production methods (isolated microspore culture and anther culture) with the same genotypes. The induction of androgenesis was more effective in isolated microspore culture than in anther culture. The number of embryo-like structures was 9.2 times higher in microspore culture (511.0/100 anthers) compared to anther culture (55.5/100 anthers) and the number of regenerant plantlets was also 3.4 times higher (anther culture—20.15/100 anthers; isolated microspore culture—67.6/100 anthers). However, the regenerant plantlets from isolated microspore culture were mainly albinos while predominantly green plantlets were regenerated from anther culture. The production of green plantlets from anther culture (16.8/100 anthers) was 2.9 times higher than from isolated microspore culture (5.8/100 anthers). The efficiency of anther culture was tested with eight winter triticale genotypes. The phenomenon of albinism did not hinder the green plant production in anther culture. Mean green plantlet production was 10.87/100 anthers. This value was two times higher than the number of albinos (5.01/100 anthers) and higher than previously published reports. The anther culture protocol described in this study is an efficient tool for the production of microspore-derived green plantlets in triticale.  相似文献   
9.
Effects of various aluminum (AlCl3) concentration and exposure times (6, 12, and 24 h and 3 d) on growth and potassium (K) transport were studied in two wheat species (Triticum aestivum L. cv. Jubilejnaja 50 and Triticum durum Desf. cv. GK Betadur) grown in low salt conditions hydroponically. In longer (3 d) Al exposure times at pH 4.1, the inhibition of root growth appeared at 10 μM Al3+ treatment in GK Betadur, and at 50 μM Al3+ treatment in Jubilejnaja 50. Shoot growth was not influenced by Al3+ treatment, except at 100 μM in 7 d experiments. In 6, 12, and 24 h Al3+ exposure times, at low pH, the K+(86Rb) influx in roots increased as the Al3+ concentration increased in the outer medium in both species. It also appeared in K+(86Rb) transport toward the shoots, except by higher Al3+ treatments of GK Betadur seedlings. At the same time, in longer‐term (3 d) Al3+ treatments, a striking inhibition were observed in K+(86Rb) influx and K+ concentration of roots and shoots. The K+concentration of roots and shoots measured at the end of 24 h Al3+ exposure times was significantly not affected by Al3+ treatment. Durum wheat proved to be more sensitive to the Al toxicity than common winter wheat.  相似文献   
10.
The present investigation aimed to study the leaf mineral composition of sweet cherry trees on different rootstocks, since the literature data on uptake efficiency of different rootstocks is inconsistent. Results confirmed the different uptake efficiency of rootstocks. The efficiency of ‘GiSelA 6’ root is emphasized in uptake and supply of leaves with nitrogen (N), phosphorus (P), potassium (K), zinc (Zn), boron (B), and manganese (Mn), but trees on this rootstock tend to develop calcium (Ca), magnesium (Mg), and copper (Cu) deficiencies. The Prunus mahaleb rootstocks on calcareous sandy soil are efficient supplier of N, P, K, Ca, Mg, Fe, and Cu, but this root tends to develop Zn, B, and Mn deficiencies. Prunus avium seedling as rootstock proved to be less efficient in supply of leaves by N, P, K, Ca, and Cu. Prunus fruticosa ‘Prob’ root showed tendency in developing several leaf nutrient deficiencies. The applied fertilizer program led to low nutrient levels or even deficiency symptoms in leaves.  相似文献   
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