Maize yield losses attributed to the stemborer; Chilo partellus (swinhoe) (lepidoptera: crambidae), in the Eastern agro-ecological Zone of Tanzania
| dc.contributor.author | Mgoo, Victor Hango | |
| dc.date.accessioned | 2026-09-01T05:15:05Z | |
| dc.date.available | 2026-09-01T05:15:05Z | |
| dc.date.issued | 2005 | |
| dc.description | Dissertation | |
| dc.description.abstract | Lepidopteran stem borers are generally considered the major biotic constraint to increased maize production in Tanzania and elsewhere in Africa. The exotic stem borer, C. partellus, is by far the most important species causing serious damage to maize and sorghum in the eastern zone of Tanzania. The effect of four nitrogen rates (0, 50, 75 and 100 kg Nha'1) on stem borer damage, growth and yield loss of maize was assessed in two seasons in two locations Kibaha and Morogoro. The results show that nitrogen had a positive effect on growth variables, mainly stem diameter, plant height and yield, and negative effect on stem borer damage and stem tunneling. At Kibaha the percentage yield loss due to natural stem borer infestation decreased with increasing nitrogen application from 52.75 % to 19.38 % in the 0 kg Nha‘’and 100 kg Nha’’rates, respectively. There was no stem borer infestation at Morogoro during the first season. During the second season, yield loss decreased from 27.09 % in the 0 kg Nha’1 to 14.84 % in the 100 kg Nha’1 rates at Kibaha, and from 13.19 % to 0.40 % in 0, and 100 kg Nha rates, respectively, at Morogoro. During the second season of 2003, maize fields were surveyed at the vegetative growth phase to asses stem borers abundance and distribution and at harvest for stem borer damage and yield loss. At vegetative stage, C. partellus was the dominant stem borer accounting . for 98.58 %, while S. calamistis accounted for 1.42 % of the population. During harvesting time, there were more S. calamistis (64 %) than C. partellus (36 %). Results from on-farm surveys showed that stem borer tunneling rec'-jced grain yield of infested plants by 10.14 %. A 16.63 % yield loss was found in plants with more than 15 cm tunnels. Stem diameter, plant height, and stem tunneling were found to be the key variables affecting maize grain yield. | |
| dc.description.sponsorship | International Center of Insect Physiology and Ecology (ICIPE), Nairobi, Kenya and Kibaha Tanzania | |
| dc.identifier.uri | https://www.suaire.sua.ac.tz/handle/20.500.14820/7945 | |
| dc.language.iso | en | |
| dc.publisher | Sokoine University of Agriculture | |
| dc.subject | Chilo partellus (swinhoe) | |
| dc.subject | Agro-ecological Zone | |
| dc.subject | Tanzania | |
| dc.subject | Lepidopteran stem borers | |
| dc.title | Maize yield losses attributed to the stemborer; Chilo partellus (swinhoe) (lepidoptera: crambidae), in the Eastern agro-ecological Zone of Tanzania | |
| dc.type | Thesis |