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41.
John Beer 《Agroforestry Systems》1988,7(2):103-114
The relative importance of N fixation, organic material inputs and nutrient inputs in litterfall, as justifications for including shade trees in plantations of coffee or cacao, is discussed. According to existing data, N fixation by leguminous shade trees does not exceed 60 kg.N/ha/a. However, these trees contribute 5,000–10,000 kg. organic material/ha/a.Comparisons are made between the leguminous shade tree Erythrina poeppigiana and the non-leguminous timber tree Cordia alliodora. The former, when pruned 2 or 3 times/a., can return to the litter layer the same amount of nutrients that are applied to coffee plantations via inorganic fertilizers, even at the highest recommended rates for Costa Rica of 270 kg.N, 60 kg.P, 150 kg.K/ha/a. The annual nutrient return in this litterfall represents 90–100 percent of the nutrient store in above-ground biomass of E. poeppigiana, and hence the consequences of competition with the crop should not be a serious limitation. In the case of C. alliodora, which is not pruned, nutrient storage in the tree stems, especially of K, is a potential limiting factor to both crop and tree productivity.It is concluded that, in fertilized plantations of cacao and coffee, litter productivity is a more important shade tree characteristic than N fixation.An early version of this review was presented at the CATIE-IUFRO meeting Los Arboles de Uso Multiple en Sistemas Agroforestales, June 1985, Turrialba, Costa Rica. 相似文献
42.
Anne Richter Alexandra-Maria Klein Teja Tscharntke Jason M. Tylianakis 《Agroforestry Systems》2007,69(3):175-182
Shade coffee including many tree species is known to support generally high biodiversity. Due to low coffee prices on the
world market, many farmers have abandoned their farms, thereby creating a new ecosystem type, which has attracted increasing
interest for biodiversity conservation. Here we used pyrethrum knockdown samples to compare the arthropod community on coffee
plants of six traditionally managed coffee agroforests with those of six abandoned coffee agroforests in coastal Ecuador.
We investigated eight randomly selected coffee shrubs per site, six of them inside and two at the edge. All arthropods were
identified to orders and beetles to morphospecies. We additionally sampled the vegetation to test for vegetation-mediated
effects on the arthropod community. The number of arthropod individuals was higher in abandoned than managed coffee, driven
by the abundance of Arachnida, Blattaria, and Heteroptera, and higher in the edge than in the centre of the abandoned agroforests.
Higher arthropod abundance appeared to be closely related to arthropod diversity, as shown for beetles (r = 0.79, n = 96). Contrary to expectations, predator-prey ratios in managed agroforests was as high as in the abandoned ones. In conclusion,
abandonment of coffee agroforests greatly encourages arthropod communities, in particular in the habitat edges, and therefore,
should be considered in landscape management for conservation. 相似文献
43.
对云南保山、思茅地区部分咖啡园土样的养分分析结果,大多数土样有效P明显缺乏,有效Fe明显偏高,部分土样交换性Ca、Mg偏低,反映出咖啡园土壤肥力减退的趋势。根据土样分析检测结果,推荐了相应的施肥方案。 相似文献
44.
45.
46.
A. Loureiro M.R. NicoleV. Várzea P. MoncadaB. Bertrand M.C. Silva 《Physiological and Molecular Plant Pathology》2012,77(1):23-32
Histological and ultrastructural studies were undertaken to compare Colletotrichum kahawae growth and the sequence of responses it induced in resistant and susceptible coffee genotypes. Coffee resistance was characterized by a restricted fungal growth associated with hypersensitive-like cell death and early accumulation of phenolic compounds, such as flavonoids (cytoplasmic contents) and hydroxycinnamic acid derivatives (cell walls). This accumulation of phenols in the cell walls preceded their lignification and thickening. In the susceptible genotype, a late accumulation of hydroxycinnamic acid derivatives in a number of cell walls and the encasement of some intracellular hyphae were also observed, but these delayed host responses did not prevent fungal growth and sporulation. 相似文献
47.
48.
小粒咖啡叶片解剖结构和综合抗旱性评价 总被引:1,自引:0,他引:1
以7个品种的小粒咖啡为供试材料,通过测定叶片厚度(LT)、角质层厚度(CT)、栅栏组织厚度(PT)、海绵组织厚度(ST)、气孔密度(SD)和叶片小脉密度(VD),并计算出叶片组织结构紧密度(MTR)、叶片组织结构疏松度(MLR)和气孔面积指数(SPI),分析其抗旱能力的差异,为小粒咖啡栽培和筛选抗旱性状提供理论依据。结果表明,所选9个抗旱性指标,品种间差异显著,运用主成分分析方法结果显示,PT和MTR载荷较高,是反映小粒咖啡抗旱性信息的主要因子,可以作为评价小粒咖啡抗旱性的主要指标。其中德热169、P7963和矮卡综合抗旱能力较强,CCCA24较弱,P2,德热296和铁毕卡居中。 相似文献
49.
采用盆栽试验,设置了4个灌水水平:SI充分灌水(75%~85%θF)、DI1轻度亏缺灌水(65%~75%θF)、DI2中度亏缺灌水(55%~65%θF)和DI3重度亏缺灌水(45%~55%θF)和4个施氮水平:高氮(NH)、中氮(NM)、低氮(NL)、无氮(NN),研究了亏缺灌溉和氮营养对小粒咖啡苗木的生长及形态指标和水分利用效率的影响。结果表明,增加灌水或施氮能促进小粒咖啡生长,提高各形态指标(株高、茎粗、叶面积和枝条长度)。与无氮处理相比,施氮可使干物质累积总量提高10.88%~37.49%,水分利用效率提高24.73%~33.01%。与重度亏缺灌水处理相比,增加灌水可使干物质累积总量提高68.01%~141.90%,水分利用效率提高22.48%~40.89%。低氮充分灌水处理可提高小粒咖啡苗木的形态指标,获得较高的干物质累积和水分利用效率。 相似文献
50.
Milene Silvestrini Michele G. Junqueira Andréa C. Favarin Oliveiro Guerreiro-Filho Mirian P. Maluf Maria B. Silvarolla Carlos A. Colombo 《Genetic Resources and Crop Evolution》2007,54(6):1367-1379
Genetic diversity among 115 coffee accessions from the Coffea Germplasm Collection of IAC was assessed using SSR markers. The germplasm represents 73 accessions of Coffea arabica derived from spontaneous and subspontaneous plants in Ethiopia and Eritrea, species center of origin and diversity, 13 commercial
cultivars of C. arabica developed by the Breeding Program of IAC, 1 accession of C. arabica cv. ‘Geisha’, 13 accessions of C. arabica from Yemen, 5 accessions of C. eugenioides, 4 accessions of C. racemosa and 6 accessions of C. canephora. Genetic analysis was performed using average number of alleles per locus (A), proportion of polymorphic loci (P), Shannon’s genetic index (H′ and G′ST) and clustering analysis. All evaluated species were distinguished by a cluster analysis based on Jaccard’s coefficient.
Differentiation between the cultivated plants of C. arabica and accessions derived from spontaneous and subspontaneous plants was observed. Spontaneous and subspontaneous accessions
from Ethiopia were separated according to the geographical origin: east and west of the Great Rift Valley. Cultivated plants
showed a low genetic diversity with a division in two groups: accessions from Yemen (H′=0,028) and Brazilian commercial cultivars (H′=0,030). The results agreed with previously reported narrow genetic basis of cultivated plants of C. arabica and supported the hypotheses about domestication of the species. This study also showed a significant genetic diversity among
accessions from Ethiopia and Eritrea present in the Germplasm Collection of IAC. This diversity is specially observed in accessions
from Sidamo (H′=0,143), Kaffa (H′=0,142) and Illubabor (H′=0,147) indicating their importance as source of genetic variability for coffee breeding programs. 相似文献