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831.
SUMMARY

We have described the flowering and fruiting phenology of 14 accessions of six Opuntia species grown in Morocco: O. ficus-indica, O. robusta, O. aequatorialis, O. dillenii, O. leucotricha, and O. stricta. We also determined the physicochemical characteristics of their cladodes. For each accession, we used four-to-20 plants. Two systems were used to measure phenology: the extended Biologische Bundesanstalt, Bundessortenamt und Chemische Industrie (BBCH)-scale and the National Phenology Monitoring System. Five principal stages were described: the development of vegetatively-propagated organs (vegetative buds), the development of flower buds, flowering, fruit development, and fruit maturity. The number of vegetative buds varied significantly among the 14 accessions, while only four accessions produced flower buds. After reaching their final size, fruit lengths varied from 3.40–6.40 cm, while fruit diameters varied from 1.93–3.90 cm. The average cladode number differed significantly among genotypes and varied from 1.75–7.75. There were also significant differences in cladode length (13.75–30.63 cm), width (6.25–17.33 cm), thickness (0.65–1.38 cm), fresh weight (FW; 67.50–766.00 g), and dry weight (DW; 8.75–67.15 g) between species. Water content and ash content, as well as total protein and total sugar concentrations, showed significant differences and were within the ranges of 86.67–92.04% (w/w), 12.97–22.08g 100 g?1 DW, 4.64–11.56g 100 g?1 DW, and 3.22–12.51 g 100 g?1 DW, respectively. Our results will help in the development of agronomic management practices and improve the characterisation, valorisation, and use of cactus pear species grown in Morocco.  相似文献   
832.
This study aimed to evaluate in vitro grafting of Theobroma cacao where seedlings of the UF 677 genotype were used as the rootstock and apices or axillary buds of a Trinitarian genotype were used as scion. Three methods of grafting using scions from seedlings were evaluated. Apical grafts using apex and side grafts using apex displayed better graft success (95 and 80%, respectively). However, side grafts using axillary buds reached a greater height on average and a higher number of leaves per plant (1.76 cm and 3.72, respectively). Histological studies revealed new vascular elements at the graft union area. Side grafts with axillary buds provided the highest survival rate (82%) after the acclimatization step. A shoot of at least 1 cm with two leaves is required for plant survival after transfer to ex vitro conditions. Side grafting was carried out with axillary buds from adult trees and nursery plants. Only the grafts with buds from nursery grafted plants were successful, with a rate of 26%. Overall, side grafting with axillary buds is the most appropriate method for cacao micrografting. This method can be used for clonal propagation and for the establishment of in vivo and/or in vitro cacao germplasm collection.  相似文献   
833.
The effect of water deprivation on plant water status, photosynthetic gas exchange and fluorescence parameters in two different olive tree varieties (Olea europaea L. var. ‘koroneiki’, ‘Meski’) was studied. Two-year-old olive trees, grown in pots in greenhouse, were subjected to one of three drought treatments (i.e., mild, moderate and severe drought stress) and compared to control trees. Both the leaf water potential (Ψw) and the relative water content (RWC) of the two varieties decreased with increasing levels of drought stress. Koroneiki showed higher (less negative) values of Ψw and lower values of RWC than the Meski, particularly during severe drought stress.

Net photosynthetic assimilation and stomatal conductance declined with drought. This inactivation of photosynthetic activity was accompanied by changes in the fluorescence characteristics. The PSII maximal photochemical efficiency (Fv/Fm), the intrinsic efficiency of open PSII reaction centres (Fv′/Fm′), the photochemical efficiency of PSII (ΦPSII) and the total electron flow (Jt) decreased during the development of drought stress.

The non-quenching photochimique (qN) showed an increase in the response to water deficit. These observations are discussed in relation to the strategies developed to grow drought-resistant olive trees in arid areas.  相似文献   

834.
The effectiveness of reproduction of four Hungarian breeding lines 7, 8, W, and 0 of carp Cyprinus carpio was investigated. The highest percentage of ovulating females after Ovopel stimulation of ovulation (1/5 + 1 pellet kg?1 BW of females) was found in line 8 (100 %), in line 0, it was 86.21 %, and in lines 7 and W, the respective values were 73.68 and 76.47 %. It was noted that the breeding line significantly (P ≤ 0.05) determined the weight of the eggs (expressed in grams and percentage of female BW), the fertilization percentage, the percentage of living embryos after 24- and 36-h incubation, the total number of eggs, and the number of live embryos after 36-h incubation. The highest weight of eggs was obtained from females of line 7 (1,083.41 g) and line 8 (981.54 g), while the lowest weight was noted in the case of females of line W (804.94 g). The highest number of eggs was found in line 7 (722,300) and in line 8 (654,400). For these lines, the highest number of live embryos (36 h) was also found (624,400 and 622,200, respectively). Within each line investigated, the regression equations were derived in order to predict the weight of eggs (g), percentage of live embryos, and the number of live embryos after 36-h incubation.  相似文献   
835.
To evaluate neurological changes developing during paediatric Acute Lymphoblastic Leukaemia (ALL) therapy clinically and through electrophysiological Study of Somatosensory Evoked Potentials (SSEPs) changes in different phases of therapy. Thirty five-ALL patients with age range from 3-14 years were included compared to 30 healthy controls. History, neurological examination, complete blood counts, cytological examination of bone marrow aspirate and cerebrospinal fluid with Measurement of Serum Methotrexate (MTX) were done. The SSEPs were performed and patients subjected to another SSEP with measurement of serum MTX level before and 10 days after intra-thecal injection (IMTX). Clinical neurological findings in patients after induction were depressed deep tendon reflexes (43.3%), hypotonia (28.6%), lost pain sensation (28.6%), muscle weakness (17.1%) and movement disorders (17.1%). Percentage of delayed SSEPs after induction were at levels of brachial plexus (28.6%), spinal cord (68.6%), cortical conduction (31.4%), ERB-N13 Inter Peak Latency (IPL) (74.3%) and N13-N20 IPL (17.1%) in the studied patients. Significant prolonged latency of N13 (p = 0.005), N20 (p = 0.04) and IPL of ERB-N 13 (p = 0.005), N13-N20 (p = 0.01), Inter-Side Difference (ISD) of N13 (p = 0.01), ERB-N13 (p = 0.02) and N13-N20 (p = 0.03) after induction compared to values at diagnosis. Significant positive correlation were found between serum MTX after IMTX with N13-N20 IPL (p = 0.01), N20 ISD (p = 0.03) with significant prolongation in N20 latency, N13-N20 IPL and ISD of N20 compared to values before injection. ALL patients have prolonged latency of SSEPs at cervical cord and cortical levels which increased after IMTX due to axonal injury throughout the cord. SSEPs could be an early diagnostic tool for subclinical neuropathy.  相似文献   
836.
A study undertaken to determine theOnchocerca species infecting camels that live in the same localities as cattle in the Dinder Region, Blue Nile Province, Sudan revealed concurrent infections with the bovine parasitesOnchocerca armillata in the thoracic aorta, brachiocephalic trunks and brachial arteries andOnchocerca gutturosa in the ventral side of the lamellar parts of theligamentum nuchae. The microfilariae of both species had the same predilection sites in the skin of the ears, head and neck regions. Those ofO. gutturosa outnumber those ofO. armillata but both are smaller than the respective uterine microfilariae. Males and microfilariae of both species are smaller than those of cattle origin.Part of the work was carried out while all the authors were at the Department of Parasitology, Faculty of Veterinary Science, University of Khartoum, Sudan.  相似文献   
837.
838.
839.
In a field experiment carried out over 3 years, the nitrate content of herbage from perennial ryegrass (Lolium perenne) swards increased exponentially with nitrogen application rate, but herbage nitrate content appeared to reach potentially dangerous concentrations only when nitrogen application rates were greater than those needed to stimulate dry-matter production. Thus, on average over all the harvests, maximum yield could be obtained with annual application rates of 400 kg N ha–1 (six applications of 67 kg N ha–1) for perennial ryegrass and 300 kg N ha–1 (six applications of 50 kg N ha–1) for perennial ryegrass/white clover (Trifolium repens) swards, whereas the mean nitrate concentrations were 3340 and 2929 mg NO3 kg–1 dry matter (DM) respectively. Nitrate content, however, varied considerably from harvest to harvest, reaching maxima of 9345 mg NO3 kg–1 DM at 400 kg N ha–1 for perennial ryegrass and 6255 mg NO3 kg–1 DM at 300 kg N ha–1 for perennial ryegrass/white clover. The nitrate content of herbage from perennial ryegrass/white clover swards was always greater than that of perennial ryegrass swards receiving the same rate of nitrogen application, even though in the herbage from the mixed sward the nitrate content of white clover was usually less than half that of the perennial ryegrass component. The physical environment did not have a clearly interpretable effect on nitrate content, although herbage harvested in May had a much lower nitrate content than that harvested at any other time of the season. It was not possible to find a single multiple regression equation relating herbage nitrate content to nitrogen application and to other environmental variables that explained more than 60% of the variance in herbage nitrate, but it is suggested that, by reducing the later-season nitrogen applications from 67 to 50 and finally to 33 kg N ha–1 for perennial ryegrass and from 50 to 33 kg N ha–1 for perennial ryegrass/white clover, it would be possible to achieve over 90% of the maximum yield while reducing average nitrate content to <40% of that at maximum yield, with no samples containing more than 2300 mg NO3 kg –1 DM.  相似文献   
840.

The present study evaluated effects of the degree of hydrolysis and peptide profile of sardine (Sardinella sp.) protein hydrolysates (SPH) from muscle tissue wastes on productive performance, body composition, hematological parameters, biochemical parameters of metabolism, antioxidant response, and intestinal microbiology tilapia (Oreochromis niloticus). Diets containing three SPH with different degrees of hydrolysis (low: 5.5%; intermediate: 27.9%, and high: 62.5%) were compared to a control diet with fish meal. The experimental design was completely randomized with four treatments and five repetitions. One hundred eighty tilapia juveniles (6.16?±?2.0 g) were distributed in 20 polyethylene tanks of 70 l of useful volume and were evaluated during 56 days. No direct relationship was observed between the degree of hydrolysis of SPH and fish productive performance. Feed consumption was reduced in all diets with SPH (means 53.03 g) compared to the control group (65.91 g), which impaired fish growth and metabolic reserves. Feed utilization was affected by the SPH peptide profile. SPH with a more diverse peptide profile (mean 1.40) had a feed efficiency similar to the control diet (1.22). Changes in biochemical and metabolic parameters in tissues, oxidative response, and microbial populations were observed but may be associated with the low consumption of diets containing SPH. Results suggest that it is necessary to properly characterize hydrolysates and understand their composition before applying fish feed.

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