Indigenous Knowledge on Parent Adult Tree Locust, Anacridium melanorhodon melanorhodon (Orthoptera: Acrididae) at Ennohoud Locality, West Kordofan State, Sudan

Rahama*4

Kordofan, Sudan

respondents confirm that eggs were laid at June and the peak of eggs hatching occurred at August.

Keywords: West Kordufan; Acacia Senegal; Tree locust; Anacridium; Indigenous Knowledge

Introduction

Acacia senegal (L.) Willd. (Hashab) is an important woody tree species that gained, as a major source of Gum Arabic, a great socio-economic and environmental importance in the Sudan [1, 2]. Natural stands of the A. senegal is dominating, what is commonly known as, the Gum Arabic belt which is occupying the area between latitudes 10°–14°N, [3]. This belt is considered as an important biome that accommodates around one fifth of the Sudan’s population and two thirds of its livestock population in addition to other living components that enrich the biodiversity [4]. Gum Arabic is the most important product of this low input production system, which significantly contributes to domestic income and hard currency earnings for the Sudan. The country is accounted for production of more than 70% from the globally marketable Gum Arabic [5, 6, 7, 8, 9]. In Sudan, Kordofan region is historically very famous for the production of Gum Arabic, where Hashab tree is grown and 70% of the Sudanese Gum Arabic was produced [7].

Gum Arabic production is drastically decreased as Hashab tree faced multitude of environmental and biological constraints that lead together with other social factors to a rigorous deterioration in the natural stands of tree. As far as the biological constraints are concerned, insect attacks were implicated as the main causal agents in the decline of the Gum production [10]. Bashier EM [11] reported serious damage by the locust during season 1991/ 1992, where losses in Gum Arabic production were estimated at 86.5%. The effect of the tree locust was neglected or uncared for; however, this locust received a great attention as a pest of many crops in traditional rain- fed areas of western Sudan [12]. Adults were found throughout the year except in February, March and April and their number decreased with increase in rainfall and relative humidity [13]. Adults of the tree locust appeared in the field in May and high populations were recorded during the period from June to September reaching the peak in November [14].

The eggs laid in moist soil during rainy season around mid-July and the estimated average incubation period was 40 days [15, 16]. Eggs hatched giving nymphal stages that develop during August and early September. During the day adults normally roost in trees, and if disturbed, they will fly from branch to branch or to a nearby tree [17]. Symmons PM [16] reported that: during summer, eggs hatched during June-July whereas fledglings were observed in August-October. Most feeding and flight activities occur at night, both adults and nymphs roost on acacia trees [18].

Materials and Methods

A questionnaire was designed to interview rural communities involved in Gum Arabic production (Hashab garden owners and Tappers) for their experience with the tree locust infestation at West Kordofan State, Ennohoud locality in season 2013/2014. Pre-test was conducted to the questionnaire. 100 respondents were randomly selected from 5 clusters. Four (4) village councils surround Ennohoud town were randomly selected and Ennohoud Crop Market. 20 respondents were randomly selected from each village council. Interviews were conducted and data was collected and summarised for analysis.

Discussion

Rahama [14] Stated that adults of the tree locust appeared in the field in May and high populations were recorded during the period from June to September reaching the peak in November Safi [13] found that adults were found throughout the year except in February, March and April. The results of this study showed that the adult mature tree locusts arrived to the area during June and July; the tree locust then leaves the area in October. The results reported herein, obtained from interviewees, are more or less in line with what was earlier indicated by the above mentioned authors. The slight differences, however, may be attributed to the fact that such type of studies maybe influenced by fluctuation of environmental factors from place to place and from season to season.

The main activity of mature adult tree locust observed by was copulation. In June and July when the adults mature tree locust were observed, the main activity was copulation this was confirmed by Safi [13] and Rahama [14].

Conclusion

• Parent adults of the tree locust arrived from elsewhere to invade Acacia senegal trees in June - July, copulation, laying eggs these activities coincide with the effective rainfall.
• Infestation of Hashab trees with locust pose great impacts on taping date and losses inflicted by locust in Gum Arabic production estimated to be around 50%.

Recommendations

• To get a blemish free Gum Arabic produce and to reduce pesticides residues in Gum Arabic, phenology of both Hashab tree and the tree locust should be considered for better targeting of the pest during the locust management operations.
• An area wide monitoring program to pinpoint the origin of the locust invasion and to identify factors that trigger for local and trans-border migration is crucial if efficient control measure is to be applied.