Meeting: Regional Workshop on Sorghum Improvement in Eastern Africa, 17-21 Oct. 1982, Nazreth, ET | Meeting: Regional Workshop on Sorghum Improvement in Eastern Africa, 17-21 Oct. 1982, Debre Zeyt, ET | The table of contents for this item can be shared with the requester. The requester may then choose one chapter, up to 10% of the item, as per the Fair Dealing provision of the Canadian Copyright Act | Sorghum is by far the most important field crop in the Eastern Africa area and the Yemens. It is the traditional staple crop of the region and the vast genetic variability in sorghums found in the area is not paralleled by any other region. All the major sorghum ecological zones found worldwide are present in Eastern Africa and the Yemens. Therefore the sorghum germplasm and the crop improvement research in the region has worldwide interest. The sorghum improvement efforts underway in each of the national programs of the region have been mostly done in isolation with very little interaction between them. This workshop was effective in bringing together most of the active researchers from the national programs of the region. The Ethiopian Sorghum Improvement Project (ESIP) of Addis Ababa University (AAU) was in many ways responsible for the initiation and successful implementation of this workshop. Through the papers presented and the discussions underway throughout the workshop, the participants were able to get a good overall picture of the sorghum improvement situation in the region. These proceedings document the papers presented to and the recommendations passed by the workshop. It is hoped that these proceedings will be useful to all those interested in sorghum in Eastern Africa and the Yemens.

A sorghum/pigeonpea intercropping experiment carried out for 3 years on a deep Vertisol in India examined the response to five pigeonpea populations in a 150 cm bed and furrow system at three row arrangements per bed: (a) 1 row sorghum : 1 row pigeonpea : 1 row sorghum at 45 cm between rows (SPS); (b) 1 row sorghum : 2 rows pigeonpea : 1 row sorghum at 30 cm between rows (SPPS); and (c) 1 row pigeonpea : 2 rows sorghum : 1 row pigeonpea at 30 cm between rows (PSSP). The distance between outer rows of adjacent beds was 60 cm. Pigeonpea seed yield in the intercropping system responded to plant populations above the sole crop optimum of 40 000 plant/ha but the response for the combined yield of both crops was less because of decreasing sorghum yield. Maximum land equivalent ration and gross monetary returns were at 70 000 plants/ha for the SPS arrangement and at 40 000 plants/ha for the SPPS and PSSP arrangements. The greater number of pigeonpea rows in SPPS and PSSP produced more pigeonpea yield but less sorghum yield; this resulted in a net benefit for the SPPS arrangement though not for the PSSP arrangement. The sorghum intercrop reduced the total branch number in pigeonpea but had little effect on the number of pod-bearing branches. Intercropping also increased the harvest index of pigeonpea because the sorghum suppressed the early vegetative growth but was harvested before the reproductive phase.

Weed occurrence and competition, and grain yield of sorghum were studied under limited and optimum irrigations. With an increase in irrigation frequency an increase in weed dry matter was observed. When the weeds were allowed to grow up to 45 days or throughout the season Dactyloctenium aegyptium (L.) Richt, Digitaria ciliaris (Ritz) Koch, Digera sp., and Echinochloa colona (L.) Link dominated the system irrespective of the moisture regime. Variation in dominance of weed species was observed under the six weed removal treatments imposed. Weeds which (i.e. after 45 days) later emerged had little effect on the sorghum grain yield. Higher reduction in sorghum grain yield due to weeds was recorded under limited irrigations than under optimum irrigation situation, thereby revealing better competitive ability of sorghum given optimum irrigations. Approximately the same sorghum grain yield could be obtained by giving five irrigations and allowing the weeds to grow as that with three irrigations and keeping the sorghum weed free. Under limited irrigations the water use efficiency of the sorghum maintained weed free was twice that of weedy check

Extract: Sorghum formulated products (SFP) were developed that included sorghum, wheat and soy flours (SWSoy); sorghum, wheat, cowpea, and soy flours (SWCSoy); sorghum, wheat and cowpea flours plus peanut butter (SWCP); sorghum and wheat flours plus peanut butter (SWP); and sorghum and wheat flours plus peanut butter and soy flour (SWPSoy). Protein efficiency ratio (PER) was 2.37 for SWSoy. The PER for SWSoy diet was not different from the casein diet. Net Protein Ratio (NPR) values ranked the same as PER and correlated with NPR. The in vivo digestibility for SWSoy was 90.2% and 81.1% when in vitro method was used. Calculated values in SWSoy met the FAO essential amino acid pattern. The product had a PER above 2.1, contained over 25% of calories as fat, was 17.9% protein and had a net dietary protein/calories of 10% as recommended by the Protein Advisory Group in formulating high protein foods for children. (author)

Five varieties of sweet sorghum, Ramada, Roma, Rio, Wray and Keller were planted for observation on key pests and potential pests: and also observed on beneficial insects as the natural enemies of insect pests of the sweet sorghum. A key pest of sweet sorghum during seedling stage is a sorghum shoot fly and during growing stage is an aphid. Natural enemies of an aphid found on this experiment are one species of predatory syrphid fly and five species of coccinellid beetles as predators and also found one species of an aphid parasite.

Results obtained in the feeding trial of corn and sorghum showed that substituting corn with sorghum in the diet of broilers decreases its palatibility. Significant reduction in palatability was noted when 50% or more of corn was replaced by equal amounts of sorghum. Gain in weight and feed efficiency were not affected although a slight reduction in both parameters were noted as more of corn was replaced by sorghum. The crude protein digestibility of the rations were comparable except when sorghum replaced totally the corn in the rations. Dry matter digestibility decreased significantly when increasing level of corn was replaced by sorghum in the rations. Results obtained showed that replacing corn with rough rice in the diet of broilers did not significantly affect feed consumption, feed efficiency weight gain and crude protein digestibility. A significant reduction in dry matter digestibility however was noted when 50% of corn was replaced by rough rice

Sorghum is by far the most important field crop in the Eastern Africa area and the Yemens. It is the traditional staple crop of the region and the vast genetic variability in sorghums found in the area is not paralleled by any other region. All the major sorghum ecological zones found worldwide are present in Eastern Africa and the Yemens. Therefore the sorghum germplasm and the crop improvement research in the region has worldwide interest. The sorghum improvement efforts underway in each of the national programs of the region have been mostly done in isolation with very little interaction between them. This workshop was effective in bringing together most of the active researchers from the national programs of the region. The Ethiopian Sorghum Improvement Project (ESIP) of Addis Ababa University (AAU) was in many ways responsible for the initiation and successful implementation of this workshop. Through the papers presented and the discussions underway throughout the workshop, the participants were able to get a good overall picture of the sorghum improvement situation in the region. These proceedings document the papers presented to and the recommendations passed by the workshop. It is hoped that these proceedings will be useful to all those interested in sorghum in Eastern Africa and the Yemens.