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31.
Claude Bakoumé Benjamin Adon Benoît Cochard Françoise Potier Tristan Durand-Gasselin Philippe Amblard 《Euphytica》2001,121(1):59-64
Following a survey involving wild oil palm groves in Côte d’Ivoire as a whole in 1968, 17 parents were chosen at Yocoboué (southernCôte d’Ivoire). Agronomic performance of the 17 parents was assessed through Deli × Yocoboué hybrids in 3 trials grown at La Mé (Côte d’Ivoire), Mondoni and La Dibamba (Cameroon).When compared to the Deli × La Mé progenies used as controls, the Deli × Yocoboué hybrids produced 91% for total bunch weight and86% for oil yields. However, the genetic variability within the Deli × Yocoboué progenies allows to select individual progenies as productive as the Deli × La Mé controls, for breeding purposes. A study of major agronomic traits led to the choice of parent YO 11 T , which combines the largest number of favourable traits. On average, Deli × Yocobouéprogenies have slower vertical growth and are susceptible to Fusarium wilt, except 2 parents (YO 3 T and YO 9 T), which seem to be resistant. 相似文献
32.
The potential influence of drying, liming, tilling, bacterial augmentation, and nitrogen fertilization on respiration of pond bottom soil exposed to air between crops was evaluated in laboratory studies using soil respiration chambers. The optimum soil moisture concentration for respiration was 12–20%, and further drying decreased soil respiration. Soil respiration was greatest at pH 7.5–8.0, and both calcium hydroxide and calcium carbonate were effective in enhancing respiration of acidic soil. Pulverization of soil to eliminate the hard surface crust formed on drying accelerated respiration, thus tilling of pond bottom soils would be expected to increase respiration. Nitrogen fertilization showed some benefit to soil respiration, but there was no value in bacterial augmentation. These laboratory findings provide background information useful to pond studies on bottom soil treatments. 相似文献
33.
Current payment for environmental service (PES) schemes face challenges in the form of evaluation of opportunity costs and ecosystem service delivery, high transaction costs, and difficulties in ensuring conditionality. Even when these conditions are met, PES may be undermined by a lack of inclusivity, leading to societal conflicts over land use. We propose a new PES-type approach that we call Landscape Labelling that seeks to overcome these problems by combining PES and product certification principles applied at a landscape scale with local benefits realized at the community level. 相似文献
34.
Forty-five soil samples were collected from aquaculture areas in 23 provinces of Thailand to include six soil orders and wide variation in physical and chemical properties. Soil-water microcosms were prepared containing 5 g of soil and 150 mL of distilled water. Microcosms were held on an oscillating table shaker (150 rpm) for 1 wk at 25 C in the dark. Water pH and concentrations of dissolved nutrients, total alkalinity, and total hardness were measured. Differences in properties within soil orders caused wide variation in composition of solutions and differences in concentrations of dissolved substances and pH were not related to soil order. Regression analyses revealed significant correlations between concentrations of soil nutrients extractable in dilute acid (0.05 N HCI plus O.025 N H2 SO4 ) or in neutral, 1 N ammonium acetate and aqueous concentrations. Regression coefficients usually were higher for dilute-acid extractable nutrients than for ammonium acetate extractable ones. Regression coeficients based on dilute-acid extractable nutrients follow: soluble reactive phosphorus ( r = 0.816); calcium ( r = 0.685); magnesium ( r = 0.470); potassium ( r = 0.959); sodium ( r = 0.977); manganese ( r = 0.462); boron ( r = 0.399). The correlation between soil and solution iron was not significant and aqueous concentrations of copper and zinc were below detection limit. Hardness was correlated with soil carbon ( r = 0.710) and soil pH was a good predictor of alkalinity ( r = 0.877). Soil pH and aqueous pH were highly correlated (r = 0.939). Findings suggest that soil characteristics can be used to predict pH and concentrations of several dissolved substances in soil-water systems under aerobic conditions. 相似文献
35.
The pH change in 40 ml of buffer caused by 20 g dry soil may be multiplied by 5600 to provide the lime requirement of mud in a fish pond. The buffer contains 10 g p-nitrophenol, 7.5 g boric acid, 37 g potassium chloride, and 5.25 g potassium hydroxide dissolved and diluted to 1000 ml with distilled water; the buffer pH is adjusted to 8.00. 相似文献
36.
37.
Sodium polyphosphate and triple superphosphate were used as sources of polyphosphate and orthophosphate, respectively, at equal P2O5 application rates in sunfish (Lepomis spp.) ponds. Filtrable orthophosphate and total phosphorus concentrations were generally higher in ponds treated with polyphosphate. However, differences between chlorophyll a concentration and net sunfish production did not differ between treatments (P > 0.05). 相似文献
38.
This case report describes a cat with metastasis of a bronchial adenocarcinoma to the abdominal skin. The cat had been treated with antibiotics and corticosteroids for several episodes of coughing when it acutely developed erythema, pustules and plaques on the abdominal skin. Diagnosis was based on cytological examination of fine-needle aspirates of cutaneous pustules, X-ray examination of the thorax and histological examination of skin biopsy samples. As the prognosis was poor, the cat was euthanased. Necropsy findings confirmed the diagnosis. Cutaneous metastases of lung carcinoma are rare in cats but have been reported in the digits with underlying bone involvement. To the authors' knowledge, this is the first report of metastasis of a feline bronchial carcinoma to the ventral skin. 相似文献
39.
Inge M. Hanssen Anneleen Paeleman Lieve Wittemans Kris Goen Bart Lievens Claude Bragard Alfons C. R. C. Vanachter Bart P. H. J. Thomma 《European journal of plant pathology / European Foundation for Plant Pathology》2008,121(2):131-146
Over a period of a few years, Pepino mosaic virus (PepMV) has become one of the most important viral diseases in tomato production worldwide. Infection by PepMV can cause
a broad range of symptoms on tomato plants, often leading to significant financial losses. At present, five PepMV genotypes
(EU, LP, CH2, US1 and US2) have been described, three of which (EU, LP and US2) have been reported in Europe. Thus far, no
correlation has been found between different PepMV genotypes and the symptoms expressed in infected plants. In this paper,
the genetic diversity of the PepMV population in Belgian greenhouses is studied and related to symptom development in tomato
crops. A novel assay based on restriction fragment length polymorphism (RFLP) was developed to discriminate between the different
PepMV genotypes. Both RFLP and sequence analysis revealed the occurrence of two genotypes, the EU genotype and the CH2 genotype,
within tomato production in Belgium. Whereas no differences were observed in symptom expression between plants infected by
one of the two genotypes, co-infection with both genotypes resulted in more severe PepMV symptoms. Furthermore, our study
revealed that PepMV recombinants frequently occur in mixed infections under natural conditions. This may possibly result in
the generation of viral variants with increased aggressiveness. 相似文献