Effect of variety mixtures on cowpea vegetable leaf and seed yields in a traditional cowpea/maize intercropping system in the semi-arid tropics of Uganda
| dc.contributor.author | Okonya, Joshua S. | |
| dc.date.accessioned | 2026-02-17T07:57:28Z | |
| dc.date.available | 2026-02-17T07:57:28Z | |
| dc.date.issued | 2009 | |
| dc.description | Dissertation | |
| dc.description.abstract | Cowpea is considered to be one of the top four leafy vegetables in Uganda grown for both its seed and leaves. Vegetable leaves are more popular than seed in the Eastern and Northern parts of the country and are a source of protein and micronutrients for the resource-poor subsistence farmers. Cowpea is usually grown in intercrop with maize, sorghum, cassava or mung bean but sole cropping is also practiced by several farmers. Most farmers in Soroti and Kumi districts continue to grow landraces (‘Ecirikukwai’ and ‘Ebelat’) because no improved varieties have been successfully bred/promoted. Erratic rainfall, low soil fertility and insect pests are among the most important constraints to cowpea production in Uganda leading to low seed yields (200-400 kg/ha) while leaf yield levels had never been assessed. Agronomic strategies to optimise both leaf and seed yields like through the use of variety mixtures are long overdue. Variety mixtures containing up to four cowpea varieties were grown in intercrop with maize during the first cropping season of 2008 at NaSARRI, Serere, Kikota village and Kogili village in Eastern Uganda. The results of these three experiments indicated that: accumulated dry matter leaf yield from 3-4 harvests and seed yield ranged from 34.7 to 70.9 kg/ha and 33.4 to 551.2 kg/ha, respectively. There was no significant difference between accumulated leaf yield of mixtures and the means of their respective component varieties. Though not significant, mixtures had both positive (4.3 to 111.4%) and negative (3 to 72.5%) effects on seed yield. Seed and leaf yield did not always increase with increasing number of component varieties in a mixture. The leaf-harvesting strategy employed by farmers enhanced seed yield in some but not all the treatments. Seed yield components like pod number, seeds/pod and 100- seed weight were not significantly affected by leaf-harvesting. On average, leaf yield was more stable in plots with mixtures than those with single cowpea varieties. Levels of leaf protein and iron ranged from 27.9 to 34.8% and 164.1 to 796.3 pg/g, respectively. Cowpea leaves were ranked first by farmers from the region among the top four leafy vegetables of spider-flower, amaranth and white cabbage. | |
| dc.identifier.uri | https://www.suaire.sua.ac.tz/handle/20.500.14820/7326 | |
| dc.language.iso | en | |
| dc.publisher | Sokoine University of Agriculture | |
| dc.subject | Variety mixtures | |
| dc.subject | Cowpea vegetable leaf | |
| dc.subject | Cowpea vegetable seed | |
| dc.subject | Yields | |
| dc.subject | Traditional cowpea | |
| dc.subject | Traditional maize intercropping system | |
| dc.subject | Semi-arid tropics | |
| dc.subject | Uganda | |
| dc.subject | Nigna unguiculata | |
| dc.subject | African leafy vegetables | |
| dc.subject | agrobiodiversity | |
| dc.subject | defoliation | |
| dc.subject | nutritional quality | |
| dc.subject | Soroti district | |
| dc.subject | Kumi district | |
| dc.title | Effect of variety mixtures on cowpea vegetable leaf and seed yields in a traditional cowpea/maize intercropping system in the semi-arid tropics of Uganda | |
| dc.type | Thesis |