Host preference by the twig borer Xylosandrus compactus (Coleoptera: Scolytidae) and simulated influence of shade trees on its populations

2017 ◽  
Vol 37 (03) ◽  
pp. 183-188
Author(s):  
James Peter Egonyu ◽  
John Baguma ◽  
Isaac Ogari ◽  
Gladys Ahumuza ◽  
Gerald Ddumba
Keyword(s):  
Tree Species ◽  
Host Preference ◽  
Coffea Canephora ◽  
Real Field ◽  
Shade Trees ◽  
Alternate Host ◽  
Shade Tree ◽  
Field Situation ◽  
Generalized Linear Modelling

Abstract Xylosandrus compactus (Eichhoff) is a serious pest of Coffea canephora and Theobroma cacao in Uganda and also attacks several common shade tree species often associated with these crops. Seedlings of 10 common hosts of X. compactus were screened for preferential infestation by X. compactus, with a view to analysing the potential role of the shade trees in escalating incidence and damage by the pest. The experiment was conducted for 8 weeks in a garden of mature C. canephora infested by X. compactus that served as a natural source of infestation for the seedlings. The seedlings that became infested by X. compactus were counted weekly and the counts subjected to generalized linear modelling. Results show marked host preference by X. compactus, with T. cacao and C. canephora being the most preferred, while Eucalyptus sp. and Albizia chinensis being the least preferred. Four simulated scenarios of incidence and damage by X. compactus on a preferred crop such as C. canephora are discussed. It is suggested that it is most unlikely for unpreferred alternate host shade tree species to markedly increase populations of X. compactus on shaded preferred host plants. However, these simulations, which are based on results from potted seedlings, need to be validated in a real field situation, taking into account other ecological parameters that are likely to influence pest populations.

scholarly journals Arbuscular mycorrhizal fungi associated with shade trees and Coffea arabica L. in a coffee-based agroforestry system in Bonga, Southwestern Ethiopia

Afrika Focus ◽  
2013 ◽  
Vol 26 (2) ◽  
pp. 111-131
Author(s):  
Tadesse Chanie Sewnet ◽  
Fassil Assefa Tuju
Keyword(s):  
Arbuscular Mycorrhizal Fungi ◽  
Tree Species ◽  
Mycorrhizal Fungi ◽  
Arbuscular Mycorrhizal ◽  
Am Fungi ◽  
Shade Trees ◽  
Coffee Production ◽  
Shade Tree ◽  
Significant Difference ◽  
Cordia Africana

In a first step to understand the interactions between Colfea arabica L. trees and mycorrhizae in Ethiopia, an investigation of the current mycorrhizal colonization status of roots was undertaken. We sampled 14 shade tree species occurring in coffee populations in Bonga forest, Ethiopia. Milletia ferruginea, Schefflera abyssinica, Croton macrostachyus, Ficus vasta, F. sur, Albizia gummifera, Olea capensis, Cordia africana, Ehretia abyssinica, Pouteria adolfi-friederici, Pavetta oliveriana, Prunus africana, Phoenix reclinata and Polyscias fulva. Coffee trees sampled under each shade tree were all shown to be colonized by arbuscular mycorrhizal fungi (AM fungi). Four genera and 9 different species of AM fungi were found in the soils. Glomus (Sp1, Sp2, & Sp3 & Sp4), Scutellospora (Sp1 & Sp2) and Gigaspora (Sp1 & Sp2) were found under all 14 shade tree species, whereas Acaulospora (Sp1) occurred only in slightly acidic soils, within a pH range of 4.93-5.75. Generally, roots of the coffee trees were colonized by arbuscules to a greater degree than those of their shade trees, the arbuscular colonization percentage (AC%) of the former being higher than the latter (significant difference at 0.05 level). Though differences were not statistically significant, the overall hyphal colonization percentage (HC%) and mycorrhizal hyphal colonization percentage (MHC%) were shown to be slightly higher under coffee trees than under their shade trees. However, the differences were statistically significant at 0.05 level in the case of HC% values of coffee trees under Pouteria adolf-friederici and MHC% under Cordia africana. Spore density and all types of proportional root colonization parameters (HC%, MHC%, AC% and vesicular colonization percentage, VC%) for both coffee and shade trees were negatively and significantly correlated with organic soil carbon, total N, available P, EC and Zn. Correlation between arbuscular colonization for coffee (AC%) and organic carbon was not significantly positive at a 0.05 level. Incidence of specific spore morphotypes was also correlated with physical and chemical soil properties. Results indicate that AM fungi could potentially be important in aforestation and help to promote coffee production activities in Ethiopia providing an alternative to expensive chemical fertilizer use, and would offer management methods that take advantage of natural systems dynamics that could potentially preserve and enhance coffee production.

scholarly journals Investigation of Shade Tree Species Used in Tea Garden in Bangladesh

2020 ◽  
Vol 18 (1) ◽  
pp. 219-237
Author(s):  
MA Rahman ◽  
ZR Moni ◽  
MA Rahman ◽  
S Nasreen
Keyword(s):  
Tree Species ◽  
Gliricidia Sepium ◽  
Growth And Yield ◽  
Shade Trees ◽  
Shade Tree ◽  
Pests And Diseases ◽  
Tea Plants ◽  
The Right ◽  
Tephrosia Candida ◽  
Tea Leaf

The shade trees are an integral component of tea cultivation in Bangladesh. The shade trees are essential for modulating the environment of the tea ecosystem, enriching the soil fertility, reducing temperature and the evaporative capacity, conserve soil moisture and helps in the control of certain pests and diseases which are positively thermotropic in nature. The shade trees provide partial shade to the tea plants, which is important for improving the quality of the tea leaf. The right type of shade trees and their proper management is a prerequisite for successful tea crop growing. For this persists, a floristic exploration of shade trees was carried out at fifteen tea gardens in Chattogram and Moulvibazar District of Bangladesh from November 2017 to December 2018. During the investigation, a total of 44 species of Angiosperm representing 31 genera of 9 families was enlisted. For every species, scientific name, vernacular name, status, and necessary photographs are mentioned. In the assessment, the Fabaceae family shows the highest number of shade trees comprising 19 genera and 31 species. The most common permanent shade tree species among the tea gardens are Albizia odoratissima, A. chinensis, A. lebbeck, A. lucidior, A. procera, and Derris robusta. Indigofera teysmannii is frequently using as a temporary shade species in all investigated tea gardens. Cajanus cajan, Tephrosia candida, Tephrosia candida, Gliricidia sepium, Erythrina lithosperma and Desmodium gyroides species are also used as temporary shade trees in many tea gardens. Further investigations, however,are required to find out the right type of shade tree species on the growth and yield of tea plants in tea cultivation areas of Bangladesh. SAARC J. Agri., 18(1): 219-237 (2020)

The Biology of Adelges cooleyi (Gill.) (Homoptera: Phylloxeridae)

1959 ◽  
Vol 91 (10) ◽  
pp. 601-617 ◽  
Author(s):  
Margaret E. P. Gumming
Keyword(s):  
North America ◽  
Pseudotsuga Menziesii ◽  
Tree Species ◽  
Picea Glauca ◽  
Douglas Fir ◽  
Alternate Host ◽  
Shade Tree ◽  
Engelmann Spruce ◽  
Shelter Belt ◽  
Adelges Cooleyi

Adelges cooleyi (Gill.) causes galls on spruce in the forests and on shelter-belt and shade-tree plantings in Alberta. The alternate host is Douglas fir, on which the injury is less conspicuous. The tree species affected are white spruce, Picea glauca (Moench) Voss, Engelmann spruce, P. engelmanni Parry, and blue Douglas fir, Pseudotsuga menziesii (Mirb.) Franco. A. cooleyi is indigenous to North America.

scholarly journals Arbuscular mycorrhizal fungi associated with shade trees and Coffea arabica L. in a coffee-based agroforestry system in Bonga, Southwestern Ethiopia

Afrika Focus ◽  
2013 ◽  
Vol 26 (2) ◽  
Author(s):  
Tadesse Chanie Sewnet ◽  
Fassil Assefa Tuju
Keyword(s):  
Arbuscular Mycorrhizal Fungi ◽  
Tree Species ◽  
Mycorrhizal Fungi ◽  
Coffea Arabica ◽  
Arbuscular Mycorrhizal ◽  
Am Fungi ◽  
Shade Trees ◽  
Coffee Production ◽  
Shade Tree ◽  
Coffea Arabica L

In a first step to understand the interactions between Coffea arabica L. trees and mycorrhizae in Ethiopia, an investigation of the current mycorrhizal colonization status of roots was undertaken. We sampled 14 shade tree species occurring in coffee populations in Bonga forest, Ethiopia. Milletia ferruginea, Scheffiera abyssinica, Croton macrostachyus, Ficus vasta, F. sur, Albizia gummifera, Olea capensis, Cordia africana, Ehretia abyssinica, Pouteria adolfi-friederici, Pavetta oliveriana, Prunus africana, Phoenix reclinata and Polyscias fulva. Coffee trees sampled under each shade tree were all shown to be colonized by arbuscular mycorrhizal fungi (AM fungi). Four genera and 9 different species of AM fungi were found in the soils. Glomus (Sp1, Sp2, & Sp3 & Sp4), Scutellospora (Sp1 & Sp2) and Gigaspora (Sp1 & Sp2) were found under all 14 shade tree species, whereas Acaulospora (Sp1) occurred only in slightly acidic soils, within a pH range of 4.93-5.75. Generally, roots of the coffee trees were colonized by arbuscules to a greater degree than those of their shade trees, the arbuscular colonization percentage (AC%) of the former being higher than the latter (signifIcant difference at 0.05 level). Though differences were not statistically signifIcant, the overall hyphal colonization percentage (HC%) and mycorrhizal hyphal colonization percentage (MHC%) were shown to be slightly higher under coffee trees than under their shade trees. However, the differences were statistically significant at 0.05 level in the case of HC% values of coffee trees under Pouteria adolf-friederici and MHC% under Cordia africana. Spore density and all types of proportional root colonization parameters (HC%, MHC%, AC% and vesicular colonization percentage, VC%) for both coffee and shade trees were negatively and significantly correlated with organic soil carbon, total N, available P, EC and Zn. Correlation between arbuscular colonization for coffee (AC%) and organic carbon was not significantly positive at a 0.05 level. Incidence of specific spore morphotypes was also correlated with physical and chemical soil properties. Results indicate that AM fungi could potentially be important in aforestation and help to promote coffee production activities in Ethiopia providing an alternative to expensive chemical fertilizer use, and would offer management methods that take advantage of natural systems dynamics that could potentially preserve and enhance coffee production. Key words: aforestation; agroforestry, coffee groves, ecology, integrated production systems, rhizosphere, sustainable agriculture, symbiosis 

scholarly journals Shade tree timber as a source of income diversification in agroforestry coffee plantations, Peru

2019 ◽  
Vol 342 ◽  
Author(s):  
Lenka Ehrenbergerová ◽  
Zuzana Šeptunová ◽  
Hana Habrová ◽  
Ronald Hugo Puerta Tuesta ◽  
Radim Matula
Keyword(s):  
Tree Species ◽  
Agroforestry Systems ◽  
High Potential ◽  
Farm Income ◽  
Potential Contribution ◽  
Shade Trees ◽  
Individual Tree ◽  
Timber Volume ◽  
Coffee Plantations ◽  
Shade Tree

Coffee is traditionally grown in agroforestry systems. Shade trees in coffee plantations provide important ecosystem services, and their timber may also be a good source of income for coffee growers. However, key information on the value of shade tree timber and its potential contribution to the income of coffee growers based on empirical data is lacking. The income that could be obtained from shade trees was estimated for three coffee plantations with different shade tree species. To estimate the marketable timber volume of standing trees, allometric equations were developed. Our results showed that the value of the shade tree timber varied significantly. It represented only 2-3% of the annual coffee farm income on the coffee plantation dominated by native Inga spp. On the other hand, the plantation predominantly shaded by Eucalyptus trees had high potential annual (50-68% of plantation income) and total (92-96% of plantation income) timber value, followed by the plantation shaded predominantly by Pinus (32-49% of plantation income for annual timber volume and 89-94% of plantation income for total timber volume). It is evident that shade trees may be a good economic reserve for coffee growers when exotic Eucalyptus or Pinus tree species are planted. However, using individual-tree data, it was found that the relatively rare native shade tree Retrophyllum rospigliosii, which was found in almost all plantations, has a high timber value and a large timber supply, making it a shade species with high potential for agroforestry.

Characterization of non polar-polar solvent extracts from some tea plantation shade tree leaves with special reference to antioxidant and antibacterial activities

2020 ◽  
pp. 15-21
Author(s):  
Arindam Ghosh ◽  
Soumya Majumder ◽  
Sumedha Saha ◽  
Malay Bhattacharya
Keyword(s):  
Cardiac Glycosides ◽  
Polar Solvent ◽  
Reducing Power ◽  
Scavenging Activity ◽  
Shade Trees ◽  
Crude Fibre ◽  
Shade Tree ◽  
Dpph Scavenging Activity ◽  
Dpph Scavenging

Beneficial properties of shade trees of tea plantations other than their medicinal properties have been extensively studied. This research was initiated to explore the properties of some shade trees with special emphasis on their antioxidant and antibacterial properties. Leaves from shade tree like Dalbergia sissoo (DS), Cassia siamea (CS), Derris robusta (DR), Leucaena leucocephala (LL), Acacia lenticularis (AL) and Melia azedarach (MA) were used for the study. Characterization of shade tree leaves by determination of moisture, crude fibre and ash content and tests of non polar – polar solvent extracts for steroid, tannins, cardiac glycosides and coumarin, free radical scavenging, ferric reducing power, NO scavenging activities, quantification of Flavonoids and antibacterial activity were conducted. The average moisture, crude fibre and ash percentage of shade tree plants were found to be 62.95, 11.28 and 1.86 respectively. Methanol, ethanol, acetone and ethyl acetate respectively proved to be the most potent solvent for various phytochemical extractions as it gave positive results for tests like tannin, steroid, cardiac glycosides and coumarin. AL (91.46%), DR (92.69%), LL (94.32%) and MA (93.34%) leaf extracts showed a high level of DPPH scavenging activity in their water extracts. In DS (88.11%) and CS (83.23%) maximum DPPH scavenging activity was observed in Diethyl ether and Methanol extracts respectively.  Acetone extracts were more active than the water extracts in exhibiting ferric reducing power and NO scavenging activity. Summation of the quantity revealed that DS showed maximum presence of flavonoids and acetone as most potential for isolation of flavonoids. The decreasing order of summative antibacterial activity was recorded in DS, followed by CS, DR, AL, MA and LL. Chloroform showed the highest summative inhibition zone followed by ethanol, ethyl acetate, diethyl ether, acetone, water,  hexane, benzene and methanol. The antioxidant and antibacterial potential of shade trees were established.

scholarly journals Co-occurrences of tropical trees in eastern South America: disentangling abiotic and biotic forces

Plant Ecology ◽  
2021 ◽  
Author(s):  
Emma-Liina Marjakangas ◽  
Otso Ovaskainen ◽  
Nerea Abrego ◽  
Vidar Grøtan ◽  
Alexandre A. de Oliveira ◽  
...  
Keyword(s):  
South America ◽  
Tree Species ◽  
Large Scale ◽  
Environmental Filtering ◽  
Limiting Similarity ◽  
Phylogenetic Relatedness ◽  
Biogeographical Regions ◽  
Dependent Processes ◽  
Occurrence Of Species

AbstractSpecies co-occurrences in local communities can arise independent or dependent on species’ niches. However, the role of niche-dependent processes has not been thoroughly deciphered when generalized to biogeographical scales, probably due to combined shortcomings of data and methodology. Here, we explored the influence of environmental filtering and limiting similarity, as well as biogeographical processes that relate to the assembly of species’ communities and co-occurrences. We modelled jointly the occurrences and co-occurrences of 1016 tropical tree species with abundance data from inventories of 574 localities in eastern South America. We estimated species co-occurrences as raw and residual associations with models that excluded and included the environmental effects on the species’ co-occurrences, respectively. Raw associations indicate co-occurrence of species, whereas residual associations indicate co-occurrence of species after accounting for shared responses to environment. Generally, the influence of environmental filtering exceeded that of limiting similarity in shaping species’ co-occurrences. The number of raw associations was generally higher than that of the residual associations due to the shared responses of tree species to the environmental covariates. Contrary to what was expected from assuming limiting similarity, phylogenetic relatedness or functional similarity did not limit tree co-occurrences. The proportions of positive and negative residual associations varied greatly across the study area, and we found a significant tendency of some biogeographical regions having higher proportions of negative associations between them, suggesting that large-scale biogeographical processes limit the establishment of trees and consequently their co-occurrences.

scholarly journals Beyond feasibility—the role of motivation to implement measures to enhance resilience

2021 ◽  
Vol 26 (5) ◽  
Author(s):  
Luzian Messmer ◽  
Braida Thom ◽  
Pius Kruetli ◽  
Evans Dawoe ◽  
Kebebew Assefa ◽  
...  
Keyword(s):  
Food Security ◽  
Conceptual Framework ◽  
General Framework ◽  
Rural Livelihoods ◽  
Weather Forecast ◽  
Reduced Tillage ◽  
Shade Trees ◽  
The World ◽  
Cocoa Farmers

AbstractMany regions around the world are experiencing an increase in climate-related shocks, such as drought. This poses serious threats to farming activities and has major implications for sustaining rural livelihoods and food security. Farmers’ ability to respond to and withstand the increasing incidence of drought events needs to be strengthened and their resilience enhanced. Implementation of measures to enhance resilience is determined by decisions of farmers and it is important to understand the reasons behind their behavior. We assessed the viability of measures to enhance resilience of farmers to drought, by developing a general framework that covers economic-technical and psychological-cognitive aspects, here summarized under the terms (1) motivation and (2) feasibility. The conceptual framework was applied to cocoa farmers in Ghana and tef farmers in Ethiopia by using questionnaire-based surveys. A portfolio of five specific measures to build resilience (i.e., irrigation, shade trees, fire belts, bookkeeping, mulching, early mature varieties, weather forecast, reduced tillage, improved harvesting) in each country was evaluated with a closed-ended questionnaire that covered the various aspects of motivation and feasibility whereby farmers were asked to (dis)agree on a 5-point Likert scale. The results show that if the motivation mean score is increased by 0.1 units, the probability of implementation increases by 16.9% in Ghana and by 7.7% in Ethiopia. If the feasibility mean score is increased by 0.1 units, the probability of implementation increases by 24.9% in Ghana and by 11.9% in Ethiopia. We can conclude that motivation and feasibility matter, and we improve our understanding of measure implementation if we include both feasibility and motivation into viability assessments.

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