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1.
通过田间试验在紫花苜蓿不同生育期内叶面喷洒硒肥和硒钴肥料,研究硒钴配施对苜蓿草地土壤肥力影响.结果表明,硒肥能够促进0~20cm土层中根系中根瘤菌的生长,改善表层土壤的结构性,促进0~10cm土层中速效氮和有机质含量的提高;硒钴配施不但能够增强硒肥功能,而且有利于提高0~20cm耕作层内速效钾的含量.  相似文献   

2.
在河南省沿黄滩区土壤以及气候条件下,通过叶面喷洒微肥来研究硒肥以及硒钴配施时不同生育期内苜蓿生长的调控以及对其土壤肥力的影响.结果表明,硒肥能够在抽茎期到开花期期间降低茎叶比,提高鲜干比,增加牧草产量.另外,硒肥能够促进0~20 cm土层中根瘤菌根系的生长,有助于0~10 cm土层中速效氮和有机质含量的提高;硒钴配施不但能够增强硒肥功能,而且有利于提高0~20 cm耕作层内速效钾的含量.  相似文献   

3.
在河南省沿黄滩区土壤以及气候条件下,通过叶面喷洒微肥来研究硒肥以及硒钴配施对不同生育期内苜蓿生长的调控以及对其土壤肥力的影响。结果表明,硒肥能够在抽茎期到开花期期间降低茎叶比,提高鲜干比,增加牧草产量。另外,硒肥能够促进0~20cm土层中根瘤菌根系的生长,有助于0~10cm土层中速效氮和有机质含量的提高;硒钴配施不但能够增强硒肥功能,而且有利于提高0~20cm耕作层内速效钾的含量。  相似文献   

4.
通过田间试验在紫花苜蓿不同生育期内叶面喷洒硒肥和硒钴肥料,研究硒钴配施对苜蓿草地土壤肥力影响。结果表明,硒肥能够促进0-20cm土层中根系中根瘤菌的生长,改善表层土壤的结构性,促进0-10cm土层中速效氮和有机质含量的提高;硒钴配施不但能够增强硒肥功能,而且有利于提高0-20cm耕作层内速效钾的含量。  相似文献   

5.
硒以及硒钴配合施用对紫花苜蓿生长的调控效应   总被引:4,自引:2,他引:2  
通过叶面喷洒硒肥以及硒钴配合肥研究其对不同生育期内紫花苜蓿生长的调控作用.结果表明:(1)2种微肥在苜蓿分枝期到开花期期间施用均能显著提高其茎叶比,降低鲜干比;(2)硒肥仅增加苜蓿营养生长期间的地上生物量,硒钴配合肥则显著增加苜蓿整个生长期间的地上生物量;(3)2种微肥均能够显著增加紫花苜蓿10~20cm土层中的地下生物量,有利于苜蓿对耕作层内土壤营养和水分的吸收和利用,其中叶面喷洒硒钴配合肥使10~20cm和0~50cm土层中的地下生物量比对照分别提高了18.9%和7.5%,比单施硒肥效果好;(4)硒肥以及硒钴配合肥对30~50cm土层地下生物量的生长有明显的抑制作用,影响到紫花苜蓿的抗旱能力且硒钴配合肥比硒肥的影响更大.  相似文献   

6.
在郑州黄河滩区紫花苜蓿草地上基施4种硒钴配施肥料(低硒低钴型、低硒高钴型、高硒低钴型和高硒高钴型)的田间试验,研究微肥基施3年后对土壤肥力的影响。结果表明:基施当年(2008)0~20cm土层中Se的有效含量平均提高了16.67%(P0.01),种植苜蓿3年后(2011);通过苜蓿吸收和富集,0~20cm土层中Se含量平均下降9.76%(P0.05);基施当年高钴肥料能使0~20cm土层中Co的含量平均提高8.24%(P0.05),种植苜蓿3年后,Co的含量平均下降5.74%(P0.05),土壤中Co的含量相对平衡,低钴肥料对土壤中钴的有效含量影响不显著(P0.05)。硒钴配施肥料会显著降低土壤中Cu、Mn和Zn3种微量元素的有效含量(P0.05),对土壤中Fe的含量影响不显著(P0.05)。试验结果提示,基施硒钴配施肥料,会降低土壤中速效钾的含量,但对土壤中碱解氮、速效磷以及有机质含量没有显著影响;硒钴配施还有降低土壤的容重和提高土壤孔隙度的作用,多次施用会破坏土壤的结构;4种硒钴配施肥料基施后能够显著影响土壤中硒的有效含量。  相似文献   

7.
硒钴配施对紫花苜蓿产草量和品质的影响   总被引:3,自引:1,他引:2  
在河南省黄河滩区,研究叶面喷洒硒肥以及硒钴配施,对紫花苜蓿产草量和品质的影响。结果表明:2种微肥在分枝期到开花期能够显著地提高苜蓿茎叶比,降低鲜干比,增加干物质含量;从开花期到成熟期能显著地提高其株高;硒肥仅能提高苜蓿营养生长期的产草量,而硒钴配施则能显著提高总产草量;硒以及硒钴配施不但能显著提高青干草中的硒钴含量,而且能显著提高Fe、Mn、Cu、Zn、Mo和B等微量元素的含量,其中以Se和Mo的提高幅度最大;硒钴配施能显著提高干草粗蛋白质、粗灰分和钙的含量,显著降低含水量和粗纤维含量,改善牧草品质。  相似文献   

8.
紫花苜蓿生长年限对土壤理化性状的影响   总被引:10,自引:0,他引:10  
2003~2005年在内蒙古民族大学试验农场连续3年测定了紫花苜蓿试验田土壤理化性状的变化.结果表明,随生长年限的增加,紫花苜蓿地0~30cm土层的土壤容重减小了0.026g/cm3,总孔隙度增加了1%,有机质的含量增加了0.8g/kg,碱解氮的含量增加了33.69 mg/kg,速效磷的含量下降了6.94 mg/kg,速效钾的含量下降了121.04 mg/kg.有机质的增加以10~20cm土层最为明显,碱解氮的增加在0~10cm和10~20cm两个土层均较明显,速效磷的减少在0~10cm土层最大,速效钾的减少在各土层均较为明显.说明紫花苜蓿高产栽培中必须重视磷、钾肥的施用,特别是要提高追施钾肥的水平.  相似文献   

9.
硒钴肥对苜蓿生长的影响   总被引:2,自引:1,他引:1  
在郑州沿黄滩区,研究叶面喷洒硒和硒钴肥(Na2SeO3·5H2O和CoSO4·7H2O)对苜蓿(Medicago sativa L.)地上、地下部生长的影响。结果表明:2种肥料从苜蓿株高15 cm开始,每隔15 d喷1次,每次用量分别为57和408 g/hm2,共喷4次,能显著提高分枝期到现蕾期的净光合能力和干物质生产速率(P<0.05);单施硒肥能显著增加从分枝期到现蕾期的有效光合叶面积,降低呼吸作用;硒钴配施能促进0~20 cm耕层苜蓿根瘤菌及根系的生长,但不利于30 cm土层以下的根系生长,虽然能增强苜蓿对表土养分和水分的利用能力,但影响其抗旱力。  相似文献   

10.
生草配合施用有机肥对省力高效梨园土壤的培肥效应研究   总被引:2,自引:0,他引:2  
为了推动果园生草在我国的推广应用,研究生草配合施用有机肥土壤管理方式对省力高效现代梨园土壤养分的作用效应,在冀中平原的“雪青”梨园,以常规清耕梨园为对照,研究省力高效梨园生草4年和生草8年的培肥效应,于2014年梨树萌芽期,在80 cm土层内分10 cm一层取样,分别测定不同土层的有机质、大量元素和微量元素含量,比较不同处理土壤营养元素的变化特征。结果表明,生草梨园0~50 cm土层有效养分含量均达到较高水平;与常规梨园相比较,这种管理模式短期(4年)增加了0~10 cm土层碱解氮、速效磷、有效锌含量和0~20 cm土层速效钾、有效铁含量,长期(8年)显著增加了0~10 cm土层有机质和碱解氮含量、0~20 cm有效铁和有效锰含量、0~30 cm速效磷和有效铜含量、0~40 cm有效锌含量和0~50 cm速效钾含量。显著降低了0~30 cm土层pH值,明显提高了河北省石灰性梨园土壤磷、铁、锌的有效性。长期生草配合施用有机肥能够增加上层土壤有效养分含量,生草8年后,0~50 cm土层速效磷、速效钾和有效锌占0~80 cm土层比重分别达到92%、82%和88%,为梨园提供充足营养的同时降低了环境污染的风险,有利于梨园土壤培肥和果园的可持续发展。  相似文献   

11.
基于我国农药信息网数据和新修订的《食品安全国家标准 食品中农药最大残留限量》(GB 2763 — 2021)中葡萄相关指标,结合葡萄生产实际,对我国葡萄上农药登记的现状及生产中农药的应用情况进行梳理,指出了存在的问题,分析了产生问题的原因,提出了相应建议,以期为我国葡萄的安全生产提供参考。  相似文献   

12.
Surgical sterilization of dogs and cats is a well-accepted measure for population control in some countries, but is considered unethical as an elective surgery in other countries. This is a review of what is known regarding positive and negative effects of gonadectomy surgery on individual animals and on societal management of unowned dog and cat populations.  相似文献   

13.
14.
Two experiments were conducted to evaluate the effects of sugar beet molasses (0, 8 and 16%) with or without lasalocid sodium (33 ppm) on rumen liquor and blood parameters of sheep, and on fattening reared Karagouniko breed lambs. In Expt. 1 six adult Karagouniko fistulated wethers were fed six different pelleted diets. The results showed that lasalocid decreased (P less than 0.01) total VFAs concentration in the rumen (7.1%) by reducing (P less than 0.001) acetic, n-butyric and iso-valeric acids while increased (P less than 0.001) propionic acid concentrations. The same trends were observed in molar proportions of the individual VFAs. The total VFAs production was also depressed by 13.75% when molasses were used at the level of 16%. No interaction among the main treatments was observed with the exception of L X M with 16% molasses where the propionic acid concentration decreased, and those of butyric and iso-valeric acids increased. Lasalocid did not alter the mean values of rumen liquor pH and ammonia nitrogen concentration while molasses increased the later parameter. No significant differences on dietary protein degradability were observed among treatments. Lasalocid reduced the beta-HBA concentration by 13% in the blood while molasses increased it (P less than 0.001). Free fatty acids' concentration was decreased by the molasses inclusion to the diets, while lasalocid didn't alter blood glucose concentration. Finally, the number of protozoa in the rumen liquor was reduced by 49 and 70% at 0 and 5 hours post feeding respectively with the addition of lasalocid to the diets, regardless of the use of molasses. In Expt. 2 utilized 86 weaned male Karagouniko fattening lambs, with initial mean LW 13 kg, for 60 days. They were assigned to six groups and fed ad libitum with diets of the same composition as in Exp 1. Lasalocid increased the growth rate by 8.6%, reduced feed consumption by 4.8% (P less than 0.005) and improved feed conversion by 11.8%. Molasses also improved growth rate by 16-34% and increased feed consumption by 15-22%. The interaction of L X M to feed consumption was significant (P less than 0.001). None of the treatments had an effect on carcass characteristics. Finally lasalocid showed its positive action when it was used in combination with molasses in ruminants' diets.  相似文献   

15.
1.?Using the so-called TOBEC (Total Body Electrical Conductivity) method, which allows the determination of egg composition in vivo, correlations between egg composition, hatchability and hatched chicks’ development were studied.

2.?A total of 1500 hen eggs (Ross-308) were measured by TOBEC, and eggs with extremely high (10%, n = 150), extremely low (10%, n = 150) and average (10%, n = 150) electrical conductivity values were chosen for further investigation.

3.?During the incubation period, it was observed that eggs with high electrical conductivity had a significantly higher mortality than eggs with low electrical conductivity.

4.?It was observed that both the increase in electrical conductivity at the same egg weight, and the increase in egg weight at the same electrical conductivity resulted in an increase in the hatching weight.

5.?It was found that the dry matter, protein and fat content of the chicks hatched from eggs with low electrical conductivity was higher at hatching than that of the chicks hatched from eggs with high electrical conductivity.

6.?At 42 d of age the liveweight of cocks and pullets hatched from eggs with low electrical conductivity was 3·2 and 8·2% higher than the liveweight of cocks and pullets hatched from eggs with high electrical conductivity.

7.?Because of the higher liveweight at slaughter, there was a significant superiority of the chicks hatched from eggs with low electrical conductivity in the case of the examined carcase traits at slaughter.

8.?Similar tendencies were found also in the ratios of carcase variables to liveweight, but the between group differences were not statistically significant in this case.

9.?Based on the results it was concluded that TOBEC seems to be a useful method for separating eggs with different composition.

10.?This could be a good starting point for further in vivo investigations in order to clarify the effect of egg composition on hatchability and further development.  相似文献   


16.
血根碱药理及毒理作用的研究进展   总被引:1,自引:0,他引:1  
血根碱(sanguinarine)作为一种苯菲啶异喹啉类生物碱,具有抗菌、抗炎、抗氧化、抗肿瘤、改善肝功能及诱导细胞凋亡等作用,同时对肝脏、心脏等具有一定的毒性。作者就血根碱对细菌、真菌和癌细胞的药理作用及毒性作一综述,为该药在临床中的有效合理应用奠定基础。  相似文献   

17.
A total of 260 New Zealand White growing rabbits were used to study the effect of diet on chemical composition of cecal contents and on production and composition of soft and hard feces. Eight diets varying in their acid detergent fiber (9.8% to 32.7%) and starch (13% to 30%) levels were evaluated. The diet affected (P less than .01) all the variables studied, except dry matter (DM) and molar proportions of volatile fatty acids on cecal contents. An increase of dietary crude fiber increased crude fiber level in cecal contents (from 11.58% to 26.53%). However, a relatively lower proportion of fibrous material was found in the cecal contents when rabbits were fed the more fibrous diets. This suggests that dietary fiber has a direct influence on the efficiency of particle separation in the digestive tract. Crude protein and volatile fatty acid concentrations of cecal contents decreased (from 30.14% to 19.65% and from 47.8 to 36.7 mmol/liter, respectively) when dietary crude fiber increased. This could be related to availability of energy to cecal microorganisms. Ammonia concentration of cecal contents was not affected by dietary crude fiber. Daily production of soft feces varied from 14.98 to 29.59 g DM/d, and the contribution of soft feces to total DM and to crude protein intake ranged from 10.6% to 15.0% and from 12.8% to 20.5%, respectively; these values were the smallest and the largest for the least and the most fibrous diets, respectively. From this study we conclude that dietary fiber has a major effect on the digestive processes in the rabbit and that dietary starch level has no influence on any of the variables studied.  相似文献   

18.
以黄芪多糖粉剂、黄芪多糖注射液作为免疫增强剂,以盐酸左旋咪唑为药物对照,通过给雏鸡添饲黄芪多糖粉剂和肌内注射黄芪多糖注射液后观察其对雏鸡免疫功能和生产性能的影响。结果表明,黄芪多糖粉剂、黄芪多糖注射液和盐酸左旋咪唑对雏鸡均有较好的免疫增强作用,黄芪多糖粉剂和黄芪多糖注射液在促进新城疫抗体效价方面作用相似,与盐酸左旋咪唑作用效果差别较小;在提高增重和E玫瑰花环形成率方面黄芪多糖粉剂和黄芪多糖注射液效果相当,但均优于盐酸左旋咪唑。  相似文献   

19.
壳聚糖是甲壳素脱乙酰基后的降解产物,具有抗微生物活性、激活淋巴细胞、提高免疫力、调节脂  相似文献   

20.
硅藻土共固定化淀粉酶和糖化酶的研究   总被引:2,自引:0,他引:2  
顾旭炯  刘璘  楼坚  张承丽 《饲料工业》2006,27(18):24-28
以糖化酶和α-淀粉酶为双酶体系、硅藻土为载体,用吸附法同时固定了这两种酶,得到的最适的共固定化条件为硅藻土(g):糖化酶(U):淀粉酶(U)=1:100:160,pH值4.5~5.0,温度5~15℃左右,缓冲液为柠檬酸缓冲液。共固定化酶的性质为:最适pH值为5.0;最适温度为55℃;米氏常数Km=16.830mg/ml;最大反应速率Vmax=1.500mg(/ml·min),其稳定性良好。  相似文献   

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