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61.
F. Kidd C. West D. G. Griffiths N. A. Potter 《The Journal of Horticultural Science and Biotechnology》2013,88(3):179-191
The volatile oil contents of dried leaves of Majorana hortensis, Melissa officinalis, Ocimum basilicum, Origanum vulgare, Salvia officinalis and Thymus vulgaris reached maximum values in summer. Different harvest dates are required in order to obtain the highest yields of dried leaves ha-1, the highest levels of volatile oil in the dried leaves, and the highest yields of volatile oil ha-1. The upper parts of balm, oregano and sage plants yielded the most dried leaves, but the lower parts showed the highest levels of volatile oil in the dried leaves. 相似文献
62.
T. W. Griffiths 《Grass and Forage Science》1959,14(3):199-205
Various forms of magnesium compounds were applied to grassland managed under modern intensive conditions and the effects on yield and composition of the herbage were measured. Magnesium limestone increased both yield and magnesium content. Commercial magnesite (MgO) increased the magnesium content rapidly and also gave a small increase in yield. An annual dressing of magnesium sulphate had little effect on magnesium content and tended to depress yield after two years.
A marked seasonal effect exists in pasture magnesium content. Increasing the magnesium content had little effect on its distribution within the plant, but it tended to depress calcium and potash.
The results are discussed with special reference to recent research on the magnesium metabolism in dairy cattle. 相似文献
A marked seasonal effect exists in pasture magnesium content. Increasing the magnesium content had little effect on its distribution within the plant, but it tended to depress calcium and potash.
The results are discussed with special reference to recent research on the magnesium metabolism in dairy cattle. 相似文献
63.
Hao Tan Matthieu Barret Marlies J. Mooij Olivia Rice John P. Morrissey Alan Dobson Bryan Griffiths Fergal O’Gara 《Biology and Fertility of Soils》2013,49(6):661-672
Fertilisers, especially nitrogen (N) and phosphorus (P) supplies, are frequently used in agricultural soil management to attain high crop yields. However, the intensive application of these chemical inputs can decrease the quality of agricultural soils and increase the probability of environmental pollution. In this study, the impact of P fertilisation on the diversity of the soil bacterial community was assessed. For this, a culture-independent approach targeting 16 rRNA and phoD genes was used on DNA extracted from pasture soils subjected to three different P fertilisation regimes for a long-term (42 years). As alkaline phosphomonoesterase (ALP) is necessary for mineralisation of organic P, an inverse relationship between the level of potential ALP activity and soil available P was expected. Indeed, a lower ALP activity was observed in soil subjected to higher chemical P fertiliser input. Analysis of the prevalence of three divergent families of ALP (PhoA, PhoD and PhoX) in metagenomic datasets revealed that PhoD is the most frequent ALP in soil samples and was selected as the most representative ALP possessed by the soil bacterial communities. Diversity of the phoD phosphorus mineraliser group, as well as the total bacterial community, was both increased in response to long-term P fertilisation. Specifically, phosphorus fertilisation decreased the relative abundance of certain taxa, including Acidobacteria and Pseudomonas fluorescens. In conclusion, this study shows that P fertilisation affects the microbial diversity of soil ecosystems, which might potentially modulate the soil biogeochemical cycle. 相似文献
64.
65.
G. R. Cayley D. C. Griffiths R. Lewthwaite B. J. Pye A. M. Dewar G. H. Winder 《Crop Protection》1987,6(6):365-370
Different designs of electrostatic sprayer (based on hydraulic, rotary atomizer or electrodynamic principles) were compared with uncharged hydraulic sprayers for application of aphicides to sugar beet and swedes. On small plants, the underleaf cover given by low-volume electrostatic systems, ‘APE 80’ and ‘Electrodyn’, enabled effective use of contact-active pyrethroid insecticides. On large plants, electrostatic systems gave no advantage over hydraulic systems and all the systems required the use of aphicides with systemic or fumigant properties to give effective control. 相似文献
66.
67.
D Griffiths 《Acta veterinaria Scandinavica》1989,30(3):355-357
In the normal dog only 2 arteries leave the ascending aorta–the brachiocephalic trunk and the left subclavian artery. This communication describes 3 dogs, a labrador, a poodle and a german shepherd, in which 3 large arteries left the ascending aorta–firstly a trunk for both common carotid arteries, then a left subclavian artery and finally a right subclavian artery. 相似文献
68.
Exencephaly and hydranencephaly were diagnosed in two 6-week-old araucana chickens (Gallus domesticus) and one adult silkie bantam (Gallus domesticus). The chickens were presented with large, subcutaneous, cranial soft-tissue masses and exhibited neurological signs. There was partial aplasia of the frontal bones, resulting in herniation of the cerebral hemispheres. 相似文献
69.
70.
Griffiths GL Lumsden JH Valli VE 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1984,13(1):13-17
Fine needle aspiration biopsy was performed on 147 skin tumors in 119 dogs over a 4-year period. Both air-dried smears (Wright's stain) and wet-fixed smears (Papanicolaou's stain) were prepared from the aspirates from each tumor and the cytological diagnosis was correlated with histology. In 105 tumors, the cytological and histological interpretations agreed. Histologically, there were 36 stromal tumors, including 19 fibrosarcomas and nine hemangiosarcomas. Cytologically, 12 of the fibrosarcomas and five of the hemangiosarcomas were interpreted correctly as malignant tumors. All 11 melanomas and all 37 mast cell tumors were identified correctly cytologically, while nine of the 11 squamous cell carcinomas, 15 of 21 adenocarcinomas and eight of 19 mammary carcinomas were interpreted as malignant using aspiration biopsy. The fine-needle technique also identified 16 dogs with metastases to the regional lymph nodes before surgical biopsies were undertaken. Benign tumors were incorrectly described as malignancies in only three cases. 相似文献