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Damage to crops by Microtermes najdensis (Isoptera, Macrotermitinae) in irrigated semi-desert areas of the Red Sea Coast. 2. Cotton in the Tokar Delta region of Sudan(Abstract. Microtermes najdensis is a major pest of cotton in the Tokar Delta of Sudan, where it causes damage by penetrating and hollowing the roots and entering the stems. Attack usually occurs late in the growing season. The efficacy of aldrin and less persistent insecticides was evaluated in a series of trials in different areas of the delta from 1982 to 1986. Plant mortality and yields varied widely among sites and years. Application of aldrin gave up to 132% increase in yield in some trials but in others no differences were detected. Treatment of seed with aldrin was more cost-effective than a planting-hole treatment. Residue levels (aldrin, dieldrin) were low in soil, cotton (seed, fibre and foliage), well water, and crops planted in plots treated with aldrin in previous seasons. Termite attack in trials of other insecticides was very low, and the efficacy of these could not be evaluated. There was no clear relationship between termite foraging activity and either plant mortality or yield.

The food‐selection of the termite Microtermes traegardhi (Sjost.), a major pest of sugarcane in the Sudan, was tested towards food previously soaked in different sugar solutions. Glucose, fructose and sucrose were chosen, as these were the principle sugar types detected in sugarcane extracts. The sugar‐content of sugarcane of different age was estimated and the significance of this in the termite infestation of the plant was discussed. Zusammenfassung Zur Rolle des Zuckergehalts bei der Nahrungswahl der Termite Microtermes traegardhi (Sjost) Unter normalen Ernährungsverhältnissen bevorzugten die Arbeiter der Termite M. traegardhi eine Nahrung (getrocknete Hirsestengel), die mit 20 %iger Zuckerlösung durchtränkt worden war. Die Reihenfolge der Bevorzugung war dabei: Fruktose, Sucrose, Glukose. Die Nahrungsaufnahme, die nach Zufügung von 20 % Zuckerlösung stark zunahm, sistierte auf einem hohen Niveau, wenn noch höhere Zuckerkonzentrationen verwendet wurden. Der Zuckergehalt von Zuckerrohr stieg mit dem Alter der Pflanze sowie bei Trockenheit an. Diese 2 Faktoren bedingen die Anfälligkeit des Zuckerrohrs gegen den Fraß der Termite.

Fruit flies belonging to the order Tephritidae are the most notorious pests that attack various fruit and vegetable species, causing severe economic losses. Guava orchards at Elfaki Hashim; North of Khartoum, (Khartoum State) and Elsawagi Elgenobia (Kassala State) in the middle and east of Sudan respectively were selected to assess the response of some Tephritids to water extracts (WE) of mango, guava, apple, cucumber, and ready-made juice of mango (Crystal®; Crystal Industrial Co. Ltd, Araak Group; crystal@araak.com) against Torula yeast (a standard fruit fly attractant) and water (control) baited in locally made traps. The trial was performed as Randomized Complete Block Design (RCBD) replicated 3 times for 5 consecutive weeks at each site. Highly significant differences were recorded between attractants and the interaction between attractants and times (weeks) on trapping different species of fruit flies. Five species of fruit flies; Ceratitis capitata, Bactrocera dorsalis, Zeugodacus cucurbitae, Ceratitis cosyra, and Ceratitis quinaria, were found to respond positively to all tested materials at both sites. The greatest number of C. capitata flies was caught by traps equipped with ready-made Crystal® mango juice at the Elfaki Hashim site. The mean number of B. dorsalis attracted to the WEs of mango and guava at Elsawagi Elgenobia site was statistically identical to that of the same species lured to Torula yeast, 83.7, 70.3, and 111.5 flies /trap/week, respectively. Attractants extracted from botanicals are cost-free and easily prepared by farmers for mass trapping of fruit flies. More studies regarding active ingredients, doses, and the number of traps utilized per area should be considered.