不同生物有机肥施肥方法对压砂西瓜生长及产量的影响

2009年在宁夏中卫香山乡采用田间试验的方法,比较了穴施和条施生物有机肥对压砂西瓜生长及产量的影响.结果表明:与条施生物有机肥相比,穴施条件下,西瓜生育前期叶面积指数增加了80％ ～ 119％；生育中后期主蔓长20.6 cm,增加25.4％；叶片数也较多；单瓜重增加了43％,中心糖含量和边糖含量分别提高了9％和8％；同...     

Fertilizer value of nitrogen in hen and broiler manure after application to spring barley using different application timing

The nitrogen (N) fertilizer effect of layer hen and broiler manure applied at different times on spring barley yield was studied in seven Swedish field experiments during 2005–2008. Two experiments had parallel field incubations to study N release after fertilizer application. The effect of total N in manure on N offtake was 30–40% that of mineral N, except in a dry year, when the effect was very low. Although the relative proportions of ammonium N, uric acid N and other N differed between the hen and broiler manure, the effect of total N was similar for both. In field incubations, mineral N decreased from 75 to 60% of total N applied in hen manure, whereas it increased from 20 to 50% in broiler manure, because of net immobilization and release, respectively. The limited fertilizer nitrogen replacement value, corresponding to only 30–40% of total N, could be as a result of ammonia volatilization after rather shallow incorporation with harrow. Net N release from broiler manure lasted for 6–8 weeks after application, after which it generally ceased. In some cases, manure application in early spring gave better yield effects than application at sowing, probably because of better synchronization of the N release with crop N requirements. The residual N effect on the N offtake in crop in the year after manure application was on average 3% of the total N applied, equivalent to a fertilizer replacement value of about 6%.     

油菜新品种宁杂1818氮肥运筹试验

以油菜(Brassica campestris L.)新品种宁杂1818为试验材料,以秦优7号为对照,研究不同氮肥运筹条件下,宁杂1818的植株长势和产量变化,旨在为深入了解宁杂1818的生长特性,建立宁杂1818高产、高效栽培技术体系提供理论依据。     

Do combined applications of crop residues and inorganic fertilizer lower emission of N2O from soil?

Emissions of N₂O were measured following addition of ¹⁵N‐labelled residues of tropical plant species [Vigna unguiculata (cowpea), Mucuna pruriens and Leucaena leucocephala] to a Ferric Luvisol from Ghana at a rate of 100 mg N/kg soil under controlled environment conditions. Residues were also applied in different ratio combinations with inorganic N fertilizer, at a total rate of 100 mg N/kg soil. N₂O emissions were increased after addition of residues, and further increased with combined (ratio) applications of residues and inorganic N fertilizer. However, ¹⁵N‐N₂O production was low and short‐lived in all treatments, suggesting that most of the measured N₂O‐N was derived from the applied fertilizer or native soil mineral N pools. There was no consistent trend in magnitude of emissions with increasing proportion of inorganic fertilizer in the application. The positive interactive effect between residue‐ and fertilizer‐N sources was most pronounced in the 25:75 Leucaena:fertilizer and cowpea:fertilizer treatments where 1082 and 1130 mg N₂O‐N/g residue were emitted over 30 days. N₂O (log_e) emission from all residue amended treatments was positively correlated with the residue C:N ratio, and negatively correlated with residue polyphenol content, polyphenol:N ratio and (lignin + polyphenol):N ratio, indicating the role of residue chemical composition in regulating emissions even when combined with inorganic fertilizer. The positive interactive effect in our treatments suggests that it is unlikely that combined applications of residues and inorganic fertilizer can lower N₂O emissions unless the residue is of very low quality promoting strong immobilisation of soil mineral N.     

Soil CO2 emission in sugarcane management systems

Sugarcane management systems affect soil attributes such as the carbon cycle. This fact has stimulated the sugar and alcohol industry to refine the sugarcane production systems by replacing the pre-harvest burning (PB) and manual harvest with mechanized harvesting followed by residue deposition. The aim of this study was to evaluate different management systems with respect to C cycling carbon dioxide and soil parameters (chemical, physical and biological) which were determined over the season. Three sugarcane cultivation systems were evaluated at the following periods: (a) PB, (b) 5-year green harvest and (c) 10-year green harvest. The results indicated that CO₂ emission was 36% greater in the 10-year sugarcane green harvest system than in the PB system. The bulk density and macroporosity were the factors that were most affected by the different sugarcane management systems and that significantly influenced soil CO₂ emissions. The principal component analysis showed that soil CO₂ emission was 18% influenced by base saturation (V%) and 14% by pH, especially in the PB area. Additionally, 19% was affected by carbon and macroporosity in the 5- and 10-year green harvest areas, respectively. From our results, it can be concluded that the most CO₂ emissions are in the areas of sugarcane green, this is due to the higher carbon concentration when compared with the area of burning sugarcane. The parameters that most influenced the CO₂ emissions were bulk density, porosity, macroporosity, pH and V%.     

Shelf-Life of Spanish Mackerel (Scomberomorus commerson) from Northern Australian Waters

Abstract

The shelf-life of Spanish mackerel caught by line fishing in Northern Australian waters was evaluated. Spiked fish were stored in ice either headed and gutted or left uncut and subjected to sensory, nucleotide, pH, histamine and microbial analysts and the rigor pattern recorded. There was little difference between the two product forms. Rigor in uncut fish lasted for 14 ± 9.8 hours and in headed and gutted fish for 19.6 ± 16.3 hours. Spanish mackerel retained good sensory quality for up to 14 days. The bacterial load reached 105 cfu/g by 18 days. K values were low for most of the storage time, < 40%. Histamine levels did not develop more than 10 mg/kg during storage. The pH of Spanish mackerel did not change much even though bacterial levels become high.     

有机无机生物活性肥料施用技术对蔬菜作物生长及产量的影响

田间试验结果表明:施用有机无机生物活性肥料能明显提高蔬菜作物长势,提高甘蓝抗根腐和烂心病能力。在等氮条件下,与常规对照相比产量基本持平,差异并不显著;但每666.7m2可节约成本24元左右,幅度达30,7%。椐统计分析,甘蓝最佳施肥置以100kg/666,7m2为宜,此用量可比常规对照增产9.3%,每666.7m2增加收入295元。在施用总量不变的条件下,减少有机无机生物活性肥料基肥比例,甘蓝则有碱产趋势。     

Altered vitamin D metabolic system in follicular cysts of sows

This study aimed to examine 25OHD₃ concentration in the fluid of follicular and follicular lutein cysts of sows in comparison with preovulatory follicles as well as immunolocalize vitamin D metabolic enzymes (CYP27B1 and CYP24A1) and determine their protein abundances in the cyst wall. We have shown for the first time that 25OHD₃ level in the fluid of both cyst types was significantly lower than in preovulatory follicles. Furthermore, we have demonstrated CYP27B1 and CYP24A1 protein immunolocalization and abundance in follicular and follicular lutein cysts. The abundance of protein for both metabolic enzymes was decreased in ovarian cysts when compared to preovulatory follicles. We propose that altered VD metabolism in ovarian cyst might associate with their formation in sows.     

抗菌肽粗提物对肉鸡生长性能、粪便微生物菌群结构及经济效益的影响

为分析抗菌肽粗提物对肉鸡生长性能、粪便微生物菌群结构及经济效益的影响,试验选择体重相近的21日龄白羽肉鸡600只,随机分成4组,每组15个重复,每个重复10只,1组为空白对照组饲喂基础日粮,试验2、3、4组在基础日粮中分别添加1.0%、1.5%、2.0%的抗菌肽粗提物,试验期为21 d。结果表明：（1）试验2、3、4组的平均采食均高于1组（P > 0.05）|试验3、4组的平均日增重较1组比分别提高11.0%、9.4%（P ＜ 0.05）,料重比较1组比分别降低18.5%、15.2% （P ＜ 0.05）|（2）试验3、4组粪便中大肠杆菌的含量较1组分别降低14.3%、18.0%（P ＜ 0.05）,试验3、4组粪便中乳酸杆菌、双歧杆菌的含量较1组比分别提高4.6%、6.7%、14.5%、12.3%（P ＜ 0.05）|（3）试验3、4组每只肉鸡经济效益较1组比分别提高19.3%、17.7%。综上,1.5%抗菌肽粗提物添加可以提高白羽肉鸡生长性能,改善粪便微生物菌群结构,提高其经济效益。 [关键词] 抗菌肽粗提物|白羽肉鸡|生长性能|粪便微生物菌群结构|经济效益     

Investigations of the maintenance system of the Konik Polski horse and its effects on fecal microbiota activity during the winter and summer seasons

Gastrointestinal microbiota play a key role in the nutrients digestion and hence maintaining animal health and welfare. The diet offered to the animals in captivity may differ considerably from that on natural pastures. In a stabled maintenance system, horses have a limited choice of habitat and feed. Time spend for feeding is relevant for equine welfare because the reduction of the time devoted for foraging may be responsible for inducing gastric inflammation and ulceration. Therefore, in the present study, it was hypothesized that fecal bacterial fermentative processes differ between free-roaming and stabled Konik Polski Horses (KPHs) with respect to microbial enzymatic activity, and thus the fecal concentration of short-chain fatty acids (SCFA), which can be further utilized for assessing the feeding behavior and welfare in free-roaming versus stabled horses. The SCFA concentration and profile, as well as the extracellular and intracellular activities of selected bacterial enzymes, were characterized in horse feces collected during the winter and summer feeding seasons. The results showed higher enzymatic activity and SCFA production in the feces excreted by free-roaming versus stabled horses, especially during summer. An increase in pasture plant diversity may be beneficial for the gastrointestinal microbiota and hence for maintaining health and welfare.