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121.
Breeding vervet monkeys in a closed environment 总被引:1,自引:0,他引:1
J V Seier 《Journal of medical primatology》1986,15(5):339-349
A breeding group of vervet monkeys produced 95 offspring over five years. Fetal wastage for 114 pregnancies was 16.7%. Uterine sizes were recorded for 103 pregnancies in various stages of gestation. This enabled diagnosis of pregnancy, estimation of stage of gestation, and prediction of parturition to within two weeks. Detailed observations were made on dental eruption, pelage development, and growth of 57 infants. 相似文献
122.
Brenda J. Biggs Michael K. Smith Kenneth J. Scott 《Plant Cell, Tissue and Organ Culture》1986,6(3):229-234
Cassava fertility and seed viability are frequently low, which can be a disadvantage in a breeding programme. An embryo culture method is described whereby embryonic axes are excised from mature seeds and placed on a culture medium containing 1.23 M indolebutyric acid (IBA) at 30°C under continuous light. The number of plants recovered by embryo culture was much greater than the number recovered from conventional seed germination procedures. 相似文献
123.
In a succession of seed harvests of carrot, the highest percentage and most rapid germination was obtained from seed harvested 51 days after anthesis (DAA) when dried by conditioning at 25°C and 60% RH for one week and from seeeds harvested 65 or 79 DAA with or without conditioning treatment. Seed from these harvests had reached maximum weight when dried, had embryos of maximum length and were considered mature. The germinaton of seed from these treatments was unaffected by a mixture of the gibberellins A4 and A7 (GA4/7) applied in the incubation medium. Seed harvested 37 DAA also gave maximum percentage germination when it was both conditioned and incubated in GA4/7 solution. Seed harvested earlier than this germinated poorly. Germination times of both mature and immature seed were reduced after storage for 18 months but there was no response to GA4/7.Abbreviations ABA
abscisic acid
- DAA
days after anthesis
- GA
gibberellin 相似文献
124.
Extract of alfalfa seed (ethanolic 50 % v/v) prevents the development of plaque formation and hyperlipidaemia in cholesterol
fed rabbits. It inhibits the elevation of serum total cholesterol, triglycerides, phospholipids, LDL-cholesterol and total
cholesterol/phospholipid ratio, while HDL-cholesterol/total cholesterol ratio increases, which is associated with a reduced
incidence of atherosclerosis. Further reduction in total cholesterol and phospholipid contents of liver and heart muscle are
suggestive of a beneficial role of the seed extract. The possible mechanisms of action are discussed. 相似文献
125.
A. Ma Fernández-Peralta J. J. González-Aguilera 《Plant Systematics and Evolution》1986,152(3-4):167-183
Six closely related taxa of the sect.Eusideritis of the genusSideritis (S. leucantha, S. pusilla, S. flavovirens, S. granatensis, S. biflora andS. osteoxylla) are analysed to elucidate their phylogenetic relationships and position within the sect.Eusideritis. Meiotic behaviour, karyotype features, size and fertility of pollen grains, DNA amounts and seed protein profiles are reviewed. A polyploid origin of the group (from x = 7) and the further diversification through dysploidy and chromosome repatterning is postulated.S. osteoxylla is apparently of hybrid origin. 相似文献
126.
Seed protein electrophoresis of four chromosomes races ofFestuca arundinacea, F. mairei and their progenitors showed variation in banding patterns. High protein similarities betweenF. arundinacea, F. mairei, F. scariosa, andF. pratensis indicate close phylogenetic relationships of these species. The ancestry ofF. arundinacea cytotypes could be narrowed to three diploid species:F. scariosa, F. pratensis, andF. rubra or to their close relatives. 相似文献
127.
R. BREGMAN F. BOUMAN 《Botanical journal of the Linnean Society. Linnean Society of London》1983,86(4):357-374
The mode of germination of representatives of 89 genera of the Cactaceae, 4 genera of Portulacaceae and 1 genus of Phytolaccaceae was studied. Most of the species of the Cactaceae germinate by means of a seed lid (operculum). In the Cactaceae studied 11 kinds of germination could be distinguished, 3 of which were with, and 8 without, operculum formation.
Opercula are restricted in their occurrence to the subfamilies Cactoideae (Cereoideae) and Pereskioideae and are not found in the subfamily Opuntioideae. Within the subfamily Cactoideae operculum formation was found to occur in all tribes and in all investigated subtribes. Opercula were also found in two genera of the related family of the Portulacaceae. In the Phytolaccaceae no operculum formation was observed. 相似文献
Opercula are restricted in their occurrence to the subfamilies Cactoideae (Cereoideae) and Pereskioideae and are not found in the subfamily Opuntioideae. Within the subfamily Cactoideae operculum formation was found to occur in all tribes and in all investigated subtribes. Opercula were also found in two genera of the related family of the Portulacaceae. In the Phytolaccaceae no operculum formation was observed. 相似文献
128.
A hitherto unknown hydroxy acid has been isolated from Blepharis sindica seed oil has been characterized as 9-hydroxydodecanoic acid by IR, NMR and mass spectral studies. The structure of this acid was further supported by its chemical transformations. 相似文献
129.
The fat of the seeds from the West African tree Pycnanthus kombo contains ca 20% of a hitherto undescribed compound. This compound was identified as 16(2′,5′-dihydroxy-3′-methylphenyl)-2,6,10,14-tetramethyl-2,6,10,14-hexadecatetraenoic acid, for which the name kombic acid is proposed. 相似文献
130.
S. J. Wallis 《International journal of primatology》1983,4(2):153-166
Gray-cheeked mangabeys live in multimale social groups. Two groups of these monkeys were studied extensively over a period
of 22 months, and a further eight groups were observed opportunistically. Data on the occurrence of sexual swelling infernales
were collected and the different phases of swelling and deflation are described in detail together with data on their duration.
The data were found to agree broadly with those presented by other workers on captive animals. Pre and postpartum swellings
are described. The majority of copulations was observed to occur at peak swelling and a specific gesture, the head flag, was
noted as a solicitation. The data on initiation of copulations show that the males initiated more copulations than the females.
However, female-initiated copulations ended in ejaculation more often than male-initiated copulations. The behaviors of the
mangabeys during precopulation and copulation were found to be broadly similar to those of the macaque. Copulations were observed
most often on the day of peak swelling;however, adult males were the only animals to copulate prior to peak swelling. Subadult male copulations were most often after
peak swelling. Masturbation was observed to ejaculation on two occasions. The data show gestation periods of between 184 and
189 days. A mean interbirth interval was calculated to be 33.33 ± 15.87 months. 相似文献