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71.
小麦顶三叶与粒重关系的研究初报   总被引:1,自引:0,他引:1  
研究了小麦不同摘叶方式下 ,顶三叶与粒重的关系及不同类型品种之间的差异。结果表明 :顶三叶的摘除对粒重的影响大小排序为旗叶 >倒二叶 >倒三叶 ,整株摘叶对粒重的影响高于主茎摘叶 ;多蘖型小麦品种主茎摘叶后千粒重降低得少 ,与整株摘叶后千粒重降低率相比差距大 ,而少蘖类型降低得多 ,降低率相比差距小  相似文献   
72.
In this study, the arterial distributions of the aortic arches of three deer species (Axis axis, Ozotoceros bezoarticus and Mazama gouazoubira) were described. The animals were dissected immediately after being found dead. Latex injection method was used to observe the vascularization of the thorax. The branching pattern of the arteries of the thoracic aorta in O. bezoarticus was similar to domestic ruminants. In the M. gouazoubira and A. axis, there were no bicarotid trunk. Interestingly, the first branch of the brachiocephalic trunk was the left costocervical trunk in A. axis. Then, brachiocephalic trunk was divided into right and left subclavian arteries. M. gouazoubira and A. axis in contrast to O. bezoarticus were different when compared with other ruminants, and the absence of bicarotid trunk was more striking than previous reports.  相似文献   
73.
The objectives of the study were to evaluate haemodynamic changes and their relationships among ipsilateral (IPS) and contralateral (CONT) uterine arteries (UA) during different stages of pregnancy in Bos indicus cows. Multiparous pregnant cows (n = 40) having a gestation length 30.47 ± 0.54 (mean ± SD) days were randomly enrolled and subjected to Doppler ultrasonography sequentially at 1st, 2nd, 4th, 6th and 8th months of gestation. Blood flow indices including diameter of UA (mm), blood flow volume (BFVo, ml/min), blood flow velocity (BFVe, cm/s), time-averaged maximum velocity (TAMV, cm/s), pulsatility index (PI) and resistance index (RI) were recorded. Data were analysed with mixed models using the PROC MIXED procedures, and Pearson correlation coefficients were calculated using the PROC CORR statement in SAS. The final statistical models included the fixed effects of side of UA, gestation month and the interaction between side of UA and gestation month. Results revealed that the mean diameter of the UA (12.13 ± 0.22 vs. 10.09 ± 0.22), BFVo (1236.33 ± 0.55 vs. 770.41 ± 0.55), BFVe (17.18 ± 0.42 vs. 15.58 ± 0.42) and TAMV (17.11 ± 0.44 vs. 15.77 ± 0.44) was higher (p < .05) in IPS as compared to CONT side of the UA in cows. However, PI and RI did not differ between IPS and CON arteries of uterus in cows. A very high and positive correlation (r = .89; p < .05) existed between the diameter of UA and BFVo starting from 1st to 8th months of gestation in IPS as well as CONT sides of UA. Moreover, TAMV was highly and positively correlated (r = .91; p < .05) with BFVe throughout the gestation. In conclusion, these haemodynamic changes in the UA could be used as a valuable validity tool to differentiate the compromised pregnancy in Bos indicus cows.  相似文献   
74.
两种塑料暖棚猪舍的应用效果观测   总被引:1,自引:0,他引:1  
在青海省乌兰县舍外温度-6.30℃条件下,选用40头荣昌猪分作2组,每组20头,在自行设计的半开放-封闭式多用塑料暖棚猪舍与常用简易塑料暖棚猪舍内开展对比试验。结果表明,前者可显著提高舍内温度,降低舍内湿度,且育猪增重效果明显。  相似文献   
75.
国外土地整理实践对我国土地整理的启示   总被引:5,自引:0,他引:5  
土地整理在我国起步较晚,很多理论还不成熟。采用文献参阅法,从土地整理的发展阶段、内容和特点等方面介绍了德国、俄国和荷兰等国外土地整理的基本情况,并由此得出其对我国土地整理的启示:建立健全土地整理法律政策,重视土地整理的权属调整,拓宽土地整理融资渠道,重视土地整理中的生态环境保护,积极推动土地整理公众参与和高度重视土地整理规划等。  相似文献   
76.
1. An experiment was conducted to determine the individual and combined effects of two essential oils, oregano and garlic, on carcass characteristics, meat composition, colour, pH and sensory quality of broiler meat.

2. The diets were supplemented with no essential oil (control), oregano essential oil or garlic essential oil at 300 mg/kg and oregano essential oil at 150 mg/kg + garlic essential oil at 150 mg/kg.

3. Dietary oregano and garlic oil supplementation did not affect carcass yields, the relative weight of carcass parts, breast and thigh meat composition, pH or b* value of breast meat. Oregano + garlic oil supplementation significantly decreased the L* value. The a* value of breast meat in birds given a diet supplemented with oregano oil was lower than that in birds given a diet supplemented with garlic oil and oregano oil + garlic oil. The essential oil addition had no positive effect on the oxidative stability. There was no difference between the treatments in breast appearance.

4. The juiciness, flavour, oxidised flavour and acceptability of breast meat samples were affected by treatments.  相似文献   

77.
烯唑醇防治香蕉叶斑病试验   总被引:1,自引:1,他引:1  
 对烯唑醇防治香蕉叶斑病效果进行试验,结果表明,烯唑醇对香蕉叶斑病有显著的防治效果,而且对香蕉生长没有抑制作用,是一个防治香蕉叶斑病优良的杀菌剂,值得在香蕉生产上推广应用。  相似文献   
78.
Artemisia annua L. is an aromatic-antibacterial herb that destroys malarial parasites, lowers fevers and checks bleeding, and of which the secondary compound of interest is artemisinin. The objective of the present study was to determine yield, yield components and artemisinin content of A. annua L. grown under four nitrogen applications (0, 40, 80 and 120 kg ha−1) in the Çukurova region of Turkey in 2004 and 2005. Field trials were conducted at Çukurova University, Agricultural Faculty Field Crops Department. In the study, plant height, number of branches, fresh herbage yield, dry herbage yield, fresh leaf yield, dry leaf yield, essential oil content and artemisinin content (by high performance liquid chromatography, HPLC) were examined. By analysis of variance, nitrogen doses had no any statistical effect on the traits investigated except for artemisinin content. Artemisinin content of the dried leaves were significantly affected by nitrogen applications, which varied from 6.32 to 27.50 mg 100 g−1. Contents were from 120 and 80 kg ha−1 nitrogen for the years of 2004 and 2005, respectively.  相似文献   
79.
经对24个板栗新品系幼树的发枝结果习性进行观测,结果表明,新品系平均结果枝占当年萌发枝的50%以上,且连续结果性能好,达到国家板栗丰产选种标准.对24个板栗新品系幼树1年生健壮枝作轻剪、中剪、重剪和不剪(缓放)4种修剪方法的试验,结果表明,轻剪能显著促进幼树发枝和座果,中剪和缓放次之,重剪结实差,发枝少而壮.  相似文献   
80.
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