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1.
M. Özgen 《Journal of Agronomy and Crop Science》1991,166(5):318-325
The purpose of this study was to compare responsiveness to environment as well as the stability of newly developed promising lines with traditional commercial cultivars. Subject research was conducted in Ankara between 1983-1989 on common and durum wheat cultivars and lines. Regression coefficient (b) was used as the criterion of genotypes' responsiveness to environment whereas deviation from regression (S2 d) and coefficient of determination (r2 ) were used as stability parameters. Each experiment year was regarded as an environment and yield average of each year was used as the environmental index.
In consequence of the research, it was determined that new varieties with high yield, adaptable to diverse environments could be developed by means of hybridizations between parents having different genetic characteristics which were provided from diverse ecological regions. 相似文献
In consequence of the research, it was determined that new varieties with high yield, adaptable to diverse environments could be developed by means of hybridizations between parents having different genetic characteristics which were provided from diverse ecological regions. 相似文献
2.
Two mungbean varieties, Guj-1 and PIMS-1 differing in their productivity potential, were examined to investigate their photosynthetic system at various stages of growth in relation to yield with two different dates of sowing. Vertical leaves were found to be beneficial. On the other hand, excessive leaf area during the later stages of growth may be detrimental to yield. Lower LAD at seedling stage and overall high NAR values may be reflected in higher grain yield. NAR declined as season progressed and this, in turn, may be related with increase in LAI. The grain yield was considerably more at the first date of sowing as compared to second date of sowing, the effect was being more pronounced in var. PIMS-1 . Various environmental factors recorded at two different dates of sowing and at various stages of growth indicated that these factors may have influenced the yield potential at two different dates of sowing. 相似文献
3.
《Livestock Production Science》2005,95(3):255-263
The aim of the experiment was to investigate the effects of cage floor and cage density on stress parameters of laying hens. A total of 162 brown laying hens (Hyline Brown), aged 34 weeks, were used in the experiment. Compact-type battery cages, with three floors, were used. Hens were allocated as one, three or five hens in each of 18 cages to obtain three different cage density groups of 1968, 656 and 393.8 cm2 floor area per hen, respectively. The same number of cages with different cage density were allocated to three different battery floors (first floor=top, second=middle, third=bottom) systematically. Values for body weight, mortality rate, egg weight, egg production, egg quality characteristics, egg yolk cholesterol content, the levels of blood plasma corticosterone, serum glucose, total cholesterol and triglycerides, the ratio of heterophils to lymphocytes (H-L ratio), antibody titers, claw length score, foot health score, plumage score and throat skin injuries were taken as indicators of stress. The values for egg weight (P<0.01) at the first floor were greater than the other floor levels. The group with five hens per cage had significantly lower mean estimates (P<0.01) than other groups with respects to body weight (P<0.001), egg production (P<0.001), egg weight (P<0.001) and plumage score (P<0.01), while significantly higher mean estimates for egg albumen index (P<0.01), Haugh unit (P<0.01), serum glucose (P<0.001), and H-L ratio (P<0.001). Serum cholesterol was higher in cages with one hen than that with five hens, whereas plasma corticosterone was lower. Antibody titers in cages with one hen was similar to that with three or five hens; however, those with three hens had higher titers than those with five hens. Values for egg breaking strength, yolk index, egg cholesterol content, and foot health score were not affected by cage density or floor. The results suggest that the allocation of three hens per cage had no measurable effect on health and welfare. 相似文献
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提出一种基于点云数据的NURBS曲面重建方法,针对数据点的分布不均匀性,进行非均匀B样条曲线控制点的反算,通过累积弦长法构造非均匀节点矢量,保证了曲面的插值精度和曲面重建的质量。 相似文献
7.
To study the effects of light, external nutrition, and hormones on the color changes of Aeonium aeonium "Halloween" leaves. In this study, the 1-year-old stem cuttings of the Aeonium aeonium "Halloween" were used as materials. The leaves were sprayed with 25mg/L methyl jasmonic acid, 3‰ potassium dihydrogen phosphate, and 1‰ calcium magnesium boron mixture for two consecutive times, with an interval of 3 days. The experiment consisted of CK (water control), LS, DS (dark culture for 1 week). After 1 week of treatment, the leaf color parameters and anthocyanin pigment content were measured every 7 days for 6 consecutive weeks. The results showed that the treatment time and method had a significant impact on the leaf color parameters. In terms of brightness value L, as the treatment time extended, all three treatments showed an upward downward upward trend. Among them, the highest value was reached after 2 weeks of treatment, gradually decreased after 3 weeks, and sharply increased again after 6 weeks; In terms of red green saturation a value, after 2-4 weeks of treatment, both LS and DS treatments were significantly higher than CK, and the effect significantly decreased after 5 weeks; Light has a significant impact on a value, with DS treatment showing a significant decrease in a value after one week of shading, and a sharp increase after re lighting; In terms of the b value of yellow and blue saturation, the change in CK value is relatively small with the extension of treatment time, while the fluctuation in LS and DS treatment is significant; In terms of color saturation c value, DS treatment significantly increased with the prolongation of treatment time, and there was no significant change in LS and CK treatment within 1-3 weeks. After 3 weeks of treatment, there was no significant difference between the three treatments; With the extension of treatment time, the anthocyanin content of each treatment showed a trend of first increasing and then decreasing. After 2-3 weeks of treatment, the anthocyanin content was higher, and gradually decreased after 4 weeks of treatment; Correlation analysis shows that anthocyanin content is highly significantly positively correlated with a and c values, and anthocyanin content is a key factor in the red color of Aeonium aeonium "Halloween". 相似文献
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梨树在自然水分亏缺下的生理反应 总被引:11,自引:0,他引:11
1994~1996年对梨树在自然水分亏缺和水分充足条件下的主要水分生理参数、气孔相对开张度(RSOD)、蒸腾速率(Tr)和光合速率(Pn)进行了比较研究。结果表明,梨树属于低水势耐旱类型,在自然水分亏缺下,其叶水势(ψw)显著降低,膨压(ψp)明显增高,而RSOD、Tr和Pn则无显著变化。梨树具有明显的渗透调节和一定的弹性调节作用,在中度水分亏缺下,其渗透调节能力△π100或△π0分别为0.44MPa和0.77MPa,弹性调节能力△|β|和△εmax分别为2.78和3.19。另外,在自然水分亏缺下,梨树叶片还具有较强的保水能力,反映在基本无变化的膨压消失点的相对含水量(R0)、叶表面水分散失率(WL0)和明显高于CK的一定ψw下的相对含水量(R)值以及无灌溉园较高的εmax或|β|等方面。 相似文献
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