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61.
A preliminary nutrient cycling study quantified total and temporal nutrient inputs via litterfall and pruning residues in two agroforestry systems: (1) Coffea arabica (perennial crop)-Erythrina poeppigiana (leguminous shade tree); and (2) C. arabica-E. poeppigiana-Cordia alliodora with emphasis on the effect of the timber tree C. alliodora. The total annual input of litterfall plus pruning residues was similar in both associations. Total annual input from E. poeppigiana was less than half in the association with C. alliodora than without, but the litterfall from this latter species compensated for the loss. Large differences in the total annual nutrient input of K, Ca and Mg was found between associations, but not for N or P. The amount of nutrients recycled by the associated trees reached the recommended level of fertilizer required for coffee production. The inclusion of C. alliodora within the C. arabica-E. poeppigiana association resulted in a more evenly distributed annual nutrient input. 相似文献
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We studied the seasonal population dynamics of Xylosandrus compactus on Coffea canephora for 24 months from June 2013 to May 2015 at the National Coffee Research Institute, Mukono, Uganda. Every month, we randomly sampled 20 infested twigs from different coffee trees on each of three experimental blocks, and dissected them to count different stages of X. compactus per twig. We recorded monthly mean temperature and total rainfall. Seasonal fluctuations in numbers of different life stages of X. compactus inside C. canephora twigs over time were analysed with a general linear model. Ambient temperature and rainfall were used to predict changes in monthly mean counts by means of a multiple linear regression. The population of X. compactus varied significantly across months and its major peak occurred from May to August. This variability was poorly explained by prevailing weather conditions with only the number of dead females correlated negatively with mean monthly temperature. Therefore, it may be suitable to apply management interventions against X. compactus on C. canephora in Uganda prior to May–August of each year to prevent the pest from attaining damaging levels. Further research is necessary to better understand the effect of weather variables on population dynamics of this insect pest. 相似文献
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C. O. Omondi 《Plant Breeding》1994,112(3):256-259
General and specific combining ability effects for resistance to coffee berry disease (Colletotrichum coffeanum Noack sensu Hindorf) in Coffea arabica variety ‘Ruiru 11’ and its parents were estimated according to the North Carolina Design II. A set of nine male parents and eleven females were crossed in all possible combinations to generate ninety-nine single cross hybrids constituting the ‘Ruiru 11’ variety. The parents and their hybrid progenies were screened and the mean score data analyzed for possible genetic variation. The contributions of the parents to the total genetic variance were low hence the low narrow sense heritability (h2= 0.04). The male and female parents accounted for 9.36 % and 0.96 %, respectively, while their interaction effect accounted for 89.68 %. In the analysis of combining ability for resistance, ExB3.96 and Cat.90 exhibited significant negative general combining ability (GCA). Specific combining abilities (SCA) were negative and significant for Cat.86 × ExB3.99, Cat.127 × ExB3.116 and Cat.119 × ExB3.879 crosses. The implications of these results in selection for highly resistant ‘Ruiru 11’ progenies are discussed. 相似文献
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以云南Arabica咖啡(Coffea arabica)、兴隆Robusta咖啡(Coffea robusta Linden)和越南Robusta咖啡为原料,采用正己烷萃取其咖啡油脂肪酸,通过GC/MS分析生咖啡及不同焙炒度咖啡的脂肪酸组成。结果表明:云南Arabica咖啡总脂肪含量高于兴隆Robusta咖啡和越南Robusta咖啡总脂肪含量;咖啡油脂肪酸含量从高到低的3种脂肪酸依次为亚油酸(约40%)>棕榈酸(约30%)>油酸(约20%);焙炒程度对咖啡油脂肪酸组成没有显著影响。此外,3种咖啡中均含有少量的亚麻酸、花生酸和山嵛酸。 相似文献
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Oliveiro Guerreiro Filho Maria Bernadete Silvarolla Albertus Bernardus Eskes 《Euphytica》1999,105(1):7-15
The coffee leaf miner (Perileucoptera coffeella, Guérin-Méneville), is the most serious pest on coffee in Brazil. Coffee varieties with resistance to this pest have been developed in Brazil using genes from the Coffea racemosa Lour. species. Resistance to P. coffeella was studied in C. racemosa and in advanced breeding populations derived from BC3 and BC4 generations through artificial infestation of coffee leaves (laboratory) and natural infestation (greenhouse). Based on an analysis of variance carried out with notes attributed to lesions, two weeks after egg hatching, C. racemosa plants and BC4 progenies were classified in 3 groups according to their degree of resistance to the insect. The age of the leaves seemed to play a role in the expression of resistance of C. racemosa and of BC4 progenies to P. coffeella. The data seemed to show that resistance to P. coffeella derived from C. racemosa can be best explained by two complementary dominant genes. Segregations for resistance assessed in families obtained by selfing or open pollination or by back-crossing with a susceptible variety were similar to the expected segregation of 9 resistant: 7 susceptible or 1 resistant: 3 susceptible, respectively. The symbols Lm1, lm1, Lm2 and lm2 are proposed for the alleles. Consequences for breeding coffee varieties with resistance are discussed. 相似文献
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咖啡营养特性及营养诊断研究进展 总被引:3,自引:0,他引:3
饮料作物咖啡(Coffea)为茜草科咖啡属的多年生灌木或者小乔木,在我国主要种植于云南与海南两省。本文概述了咖啡的主要营养特性及咖啡营养诊断方面的研究概况,并指出咖啡营养诊断的研究方向。 相似文献
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