Serological studies on Corynebacterium pseudotuberculosis infections in goats in Baden-Wuerttemberg (Germany) and seroreactions on antigens used for newly developed enzyme-linked immunosorbent assays (ELISA)

In the present study, comprehensive data on the seroprevalence of Corynebacterium (C.) pseudotuberculosis infections in goats are presented for Baden-Wuerttemberg, a Federal State of Germany, for the first time. As a prerequisite, ELISAs based on a recombinant phospholipase D (rPLD) and whole cell antigens (WCA) were designed and validated yielding sensitivity values of 81% and 97% and specificity values of 98% and 99%, respectively. Immunisation trials in goats demonstrated a significant production of antibodies to rPLD but an evidently lower antibody production to WCA as determined in the corresponding ELISA. Moreover, immunisation with rPLD resulted in the formation of antibodies, which were also detected in the WCA ELISA. In contrast, this phenomenon was not observed with the rPLD ELISA after immunisation with WCA. Implementation of the rPLD and WCA ELISAs in a broad-based seroprevalence study in Baden-Wuerttemberg revealed positive reactions in both ELISAs in 13.2% of the 1771 goat sera tested. In 53.7% of 121 herds of which five or more animals were tested per herd there was at least one animal that showed a positive reaction in both tests.     

RETRACTED ARTICLE: Distribution of carbon,nitrogen, carbohydrate and calcium carbonate in aggregates of histosols in Shahrekord,Iran

Soil organic matter and its components play a key role in the stabilization of soil aggregates. This study aimed to investigate the distribution of organic carbon (OC), total nitrogen (TN), hot-water extractable (HWE) and dilute acid extractable (DAE) carbohydrates and CaCO₃ in water-stable aggregates in histosols of Shahrekord, Iran. Additionally, correlations between aggregate stability (mean weight diameter (MWD) values) and mentioned characters were also examined. Results showed that at all depths in all 18 profiles, larger aggregates contained more OC, TN and carbohydrate content than the smaller aggregates, whilst CaCO₃ had the opposite trend. OC, TN and carbohydrate fractions followed a consistent similar trend by aggregate size. The positive correlation between OC and TN within the aggregates was considerable. OC, TN, carbohydrate fractions and MWD significantly (P < 0.01) decreased with depth. Average concentration of CaCO₃ was almost the same in aggregates <4 mm at all depths. We observed very low values of ratios HWE:OC and DAE:OC in the study site. OC, TN and carbohydrate fractions each gave highly or very highly significant correlations with aggregate stability. We obtained significant, but weak negative correlation of CaCO₃ with aggregate stability (P = 0.05; r = ?0.23), implying that CaCO₃ is a disaggregating agent in these histosols.     

焉耆盆地不同生境白刺灌丛沙堆形态特征分析

以焉耆盆地的白刺纯林、白刺 红柳混合区和白刺 胡杨混合区的灌丛沙堆为研究区域,分析不同生境白刺灌丛沙堆的长、宽、高、面积、体积、株高等方面的形态特征和形态参数间的相关性。结果表明：（1）不同生境白刺灌丛沙堆形态参数分别为长度1.2~10.7 m、宽度1.2~6.3 m、高度0.5~2.4 m、面积1.2~50.1 m²、体积0.7~80.3 m³、株高0.6~1.6 m;（2）白刺沙堆各形态参数间具有极强的相关性,其中不同生境3个样地上的白刺沙堆长度与宽度间、沙堆面积与高度、沙堆体积与面积间都表现为极显著相关。以不同生境白刺灌丛沙堆形态参数间的相关性分析结果为基础,分别对不同生境白刺灌丛沙堆长度与宽度、高度与面积、面积与体积间进行回归方程拟合,结果显示：除了白刺 胡杨混合区沙堆高度与面积的拟合方程R²为0.3853较低以外,其余白刺沙堆各形态参数间的拟合方程R²均在0.7538~0.9895之间,说明沙堆的各形态参数间的关系非常密切。研究结果对提出防风固沙的生物措施具有非常重要的科学意义。     

Yield and quality response of drip irrigated green beans under full and deficit irrigation

The effects of different irrigation regimes on yield and quality of green beans (Phaselous vulgaris L.) irrigated with a drip irrigation system under field conditions in the Mediterranean region of Turkey were evaluated along two years. Irrigation regimes consisted of four irrigation intervals based on four levels of cumulative pan evaporation (Epan) values (I₁: 15; I₂: 30; I₃: 45 and I₄: 60 mm); irrigations occurred on the respective treatments when Epan reached target values, and three plant–pan coefficients as for irrigation levels (Kcp₁ = 0.50, Kcp₂ = 0.75 and Kcp₃ = 1.00). Irrigation intervals varied from 2 to 4 days in I₁, 5 to 7 days in I₂, 8 to 10 days in I₃ and 10 to 12 days in I₄ treatments in 2004 and 2005 growing seasons Both irrigation levels and intervals significantly affected the green bean yields. Maximum and minimum yields were obtained from the I₁Kcp₃ and I₄Kcp₁ treatments as 24,320 and 14,200 kg ha⁻¹ in the first, and 23,850 and 13,210 kg ha⁻¹ in the second experimental year, respectively. As the Kcp value decreased the total yields in each irrigation interval also decreased. However, with the longer irrigation interval (I₄), lower yields were obtained with all Kcp coefficients. Seasonal water use (ET) values in the treatments varied from 276 mm in I₄Kcp₁ to 400 mm in I₁Kcp₃ in the first experimental year, and from 365 mm in I₄Kcp₁ to 472 mm in I₁Kcp₃ in the second experimental year. Significant linear relations were found between green bean yield and seasonal ET for each experimental year. Irrigation intervals resulted in similar water use in the treatments with the same Kcp value. Water use efficiency (WUE) and irrigation water use efficiency (IWUE) values were significantly influenced by the irrigation intervals and plant–pan coefficients. WUE ranged from 4.33 kg m⁻³ in I₄Kcp₃ to 6.08 kg m⁻³ in I₁Kcp₃ in 2004, and varied from 3.62 kg m⁻³ in I₄Kcp₁ to 5.43 kg m⁻³ in I₂Kcp₂ in the 2005 growing season. Maximum IWUE was observed in I₂Kcp₁ (6.16 kg m⁻³), and minimum IWUE was in I₄Kcp₃ treatment (3.83 kg m⁻³) in the experimental years. Both irrigation levels and irrigation frequencies had significantly different effects on quality parameters such as fresh bean length, width, number of seed per pod and 100 fresh bean weights. In conclusion, I₁Kcp₃ irrigation regime is recommended for field grown green beans under the Mediterranean conditions in order to attain higher yields with improved quality.