Damage to crops byMicrotermes najdensis (Isoptera, Macrotermitinae)in irrigated semi‐desert areas of the Red Sea coast 1. The Tihama region of the Yemen Arab Republic

Abstract

Microtermes najdensis is widely distributed throughout irrigated cropping areas of the Tihama region in Yemen Arab Republic. It is subterranean and damages young and mature plants by penetrating the root system and ultimately the stem, causing wilting and death. Surveys showed that plant-mortality without termite control ranged from 2-63% (average 20-30%) in cotton and maize. Pepper, okra and tomato were attacked less severely (average mortality of 10-20%). Tobacco, sorghum, millet and most vegetables suffered little damage (less than 2% stand loss) whereas experimental crops such as groundnuts, wheat and sesame suffered severe losses. Insecticides were evaluated as pre-sowing soil treatments in cotton in two trials, one near Hudaydah and one near Zabid. At Hudaydah, Microtermes foraging began late in the season and there was little damage; plant mortality in untreated plots was 8.1-9.3%. At Zabid, foraging began earlier and mortality in untreated plots was 39.7-48.5%. Aldrin and chlordane at 1.0-2.0 kg/ha gave significant control with mortality at 0.0-0.5%, in all trials. There were no significant differences in yields at Gumeisha, but at Zabid untreated plots yielded 3200-3500 kg/ha, significantly less than 3700-4500 kg/ha on aldrin and chlordane treated plots. Lindane, HCH, diazinon, phoxim, chlorfenvinphos, isofenphos (except at 7.5 kg/ha) and chlorpyrifos were significantly less effective than aldrin and chlordane in preventing mortality, even at high dose rates (e.g. 18.2-28.2% mortality at Zabid with chlorpyrifos at 14.4 kg/ha). Wood baits placed on the surface between cotton plants at Hudaydah were effectively protected at peak foraging times in the aldrin and chlordane treatments; 0-5% of baits were attacked compared with 25-26% in untreated controls and 19-25% in lindane and HCH. Diazinon (13-27%), phoxim (41%), chlorfenvinphos (55%), isofenphos (17-21%) and chlorpyrifos (21-22%) gave less effective protection than aldrin (0%). Attack on baits at Zabid in chlorpyrifos plots (31-35%) was similar to that on untreated plots (34%).

Impact des termites dans les champs paysans de riz et de mais en savane sub-soudanienne (Booro-Borotou, Côte-d\'Ivoire)

“…Les résidus de culture restés au sol, source de nourriture, stimulent la recolonisation des champs par les termites champignonnistes (Wood et al, 1980 ;Tondoh, 1992 ;Mora et al, 1996 ;Sileshi et al, 2005). Par ailleurs, Wood et al, (1977Wood et al, ( et 1980 au Nigeria sur le maïs, Kumar & Veeresh (1990) en Inde sur le blé, Wood et al, (1987) au Yémen sur le coton ont montré que les attaques des termites sont peu importantes la première année (1-2%), mais qu'elles évoluent avec le temps sur les parcelles non traitées. Au niveau du maïs, le mode d'attaque des Microtermes, Ancistrotermes, Amitermes, Pseudacanthotermes, Trinervitermes est similaire à ceux observés par Wood et al, (1980), Cowie et Wood (1989) et Cissé (1991).…”

Termite (Isoptera) control in agriculture and forestry by non-chemical methods: a review

“…and Ancistrotermes spp. have diffuse subterranean nests and attack plants from below ground by entering the root system and tunnelling up into the stem, hollowing it out and frequently filling it with soil Sands, 1973aSands, , 1973bWood et al, 1987). These characteristic modes of attack grade into each other and one genus may adopt more than one of them.…”

Damage to crops bymicrotermes najdensis(isoptera, macrotermitinae) in irrigated semi‐desert areas of the red sea coast. 2. cotton in the Tokar delta region of Sudan

“…The relationship between foraging activity, plant mortality and yield loss varies with the kind of crop (Wood et al, 1987). For groundnuts in Nigeria, Johnson et al, (1981) found a relationship between stand and yield losses, while in cotton there appears to be no clear relationship.…”

“…Foraging activity in various termite species is influenced by irrigation (Wood et al, 1987), soil water content and rainfall (Ueckert et al, 1976;Johnson er al., 1981), temperature (Badawi ef a/., 1984) and possibly by internal activity rhythms (Bouillon, 1970).…”