| dc.creator |
Elisante, Filemon |
|
| dc.date |
2020-09-22T12:15:38Z |
|
| dc.date |
2020-09-22T12:15:38Z |
|
| dc.date |
2020-04 |
|
| dc.date.accessioned |
2022-10-25T09:19:46Z |
|
| dc.date.available |
2022-10-25T09:19:46Z |
|
| dc.identifier |
https://dspace.nm-aist.ac.tz/handle/20.500.12479/939 |
|
| dc.identifier.uri |
http://hdl.handle.net/123456789/94913 |
|
| dc.description |
A Thesis Submitted in Partial Fulfilment of the Requirements for the Degree of Doctor of
Philosophy in Life Sciences of the Nelson Mandela African Institution of Science and
Technology |
|
| dc.description |
Pollination services by insects contribute to production in 75% of food crop species. When
promoted through agro-ecological intensification (AEI), pollination can narrow yield gaps in
smallholder farming systems. The study evaluated the contribution of insect pollinators on
common beans (Phaseolus vulgaris L.) yields, and the knowledge gaps pre and post-training of
smallholder farmers (n=300) in pollinators and field margins in a bean agro-system were
investigated. Also, the role of field margin as a refuge for flower-visitors, and how plants and
pollinator richness and diversity can influence strength of pollination networks in three agro
ecological zones were investigated. Baseline and end-line surveys, pollinator exclusion and
fluorescent dye-experiments, insects and vegetation surveys were carried out to obtain data for
each specific objective of the study. While the majority of farmers were unaware of pollinators
and their importance as pollinators before training, the end-line survey one year after training
showed an increase in knowledge. The majority of farmers subsequently recognized honeybees,
hoverflies and solitary bees, by names and their role as crop pollinators and natural enemies (for
the case of hoverflies). Higher yield based on pods per plant and seeds per pod on open pollinated
and hand pollinated flowers were significantly recorded compared with plants from which
pollinators had been excluded suggesting that pollinators contribute significantly to crop yield.
Similarly, it was found that field margin plants are essential in supporting higher number of
pollinator taxa and can influence their richness in adjacent bean field. Collectively these results
showed that improving understanding among smallholder farmers of ecosystem services and their
ecological requirements are both feasible and essential for conservation of insect pollinators, which
are important for optimising yield in this production system, and that crop margin vegetation
provides habitat for these ecosystem service providers. Field margins with high plant diversity
displayed extended and more robust pollination networks compared to those with low plant
diversity, and consequently these habitat strips should be managed with sensitivity for pollinating
insects and for the stability and persistence of plant-pollinator interactions in this agro-system. |
|
| dc.format |
application/pdf |
|
| dc.language |
en |
|
| dc.rights |
Attribution-NonCommercial-ShareAlike 4.0 International |
|
| dc.rights |
http://creativecommons.org/licenses/by-nc-sa/4.0/ |
|
| dc.subject |
Research Subject Categories::NATURAL SCIENCES |
|
| dc.title |
Assessing the potentials of agricultural ecosystem pollination services to improve bean yield in smallholder farming systems |
|
| dc.type |
Thesis |
|