الفهرس 
Survey of arthropods associated with cowpea plantsOnly 14 pages are availabe for public view
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Abstract
Cowpea (Vigna unguiculata (L.) Walp.) is an important legume crop.
It is subjected to be infested by several insects in field and in storage. The present investigations were carried out both at the farm of Sakha Agricultural Research Station (SARS) Kafr El-Sheikh Governorate during two successive seasons 2012 and 2013 and in the laboratory at Department of stored products pests, Plant Protection Research Institute in the same station to study the following points: A. Field Studies 1. Survey of arthropods associated with cowpea plants. a… Harmful arthropods There were 19 species of insect pests affiliated to 14 family and 7 orders during the two study seasons. The main insect pests The major insect pests include, Etiella zinckenella, C. maculatus, Empoasca decepiens, Aphis craccivora, Bemisia tabaci, Nezara viridula and Melanagromyza phseoli,. The other insect pests Include Callosobruchus chinensis, Callosobruchus quadrimaculatus, Hylemya (Paregle) cinerella, Cicadulina sp., Sesamia cretica, Cosmolyce boeticus, Spodoptera littoralis, Vanessa cardui, Euprepocnemis plorans, Aiolopus strepens and Thrips tabaci. b... Beneficial arthropods The beneificial arthropods showed the presence of 19 species in 14 families and 7 orders during the two seasons. They include Coccinella undecimpunctata, Scymnus interruptus, Paederus alfierii, Cydonia vicina, Mantis religiosa, Sphodromantis bioculata, Metasyrphus corolla Orius sp., Polistes gallica, Dirhinus sp., Opius sp., Trissolcus bassalis, Allaxysta sp., Anisopteromales calendrae, Sphigigaster sp., Ischnura senegalensis, chrysopa carnea, Cueta variegate and Hemianax ephippiger. c…Visitor arthropods The visitor arthropods revealed the presence of families8 and 4 orders for the above mentioned period. While Mites represented by two families and two orders. These include Corticarnia carinulata, Nanophyes nitidulus, Anthicus bremi, Formiconus coerulepennis v. Synopterus, Chironomus sp., Sepsis fissa, Trupanea amoena, Scantius aegyptus, Apis mellifera, Tetranychus sp. and Amblyseius gossipi. 2. Shannon Weaner diversity index (S.W.) for arthropod species on cowpea during 2012 and 2013 seasons: It could be concluded that Shanon Weaner diversity indices for harmful arthropods and beneficial arthropods were higher in the 2nd season than in the 1st one with 2.447, 2.872, 2.370 and 2.842 for 2012 and 2013, respectively. While the diversity indices for visitor insects and mites had the highest values in the 1st season with 5.076 and 0.690 than in the 2nd one with 1.872 and 0.688, respectively. 3. Population fluctuations of certain cowpea insect pests and their relation to two weather factors: The results on mean population of insect pests explicated that seven important insect pests were found harbouring cowpea plants in Kafr El- Sheikh; Bemisia tabaci, Empoasca decipiens, Nezara viridula, Melanagromyza phaseoli, Aphis craccivora, Etiella zinckenella and Callosobruchus maculatus. 3.1. Population fluctuations of Bemisia tabaci Genn: During season 2012 population of individuals appeare with relatively low number (2.7insects/10leaflets)on July 24th, then the population continued increasing to peak on 21st of August with an average of 15 individuals /10 leaflets (T. max. 34.1oC, T. min 25.1oC and R.H. max. 83%, R.H. min 51.8%). After that the population decreased gradually. In 2013 season, Bemisia tabaci started to appeare with very few individuals (0.3and 0.7/10leaflets) on 16th and 23rd July, respectively, and then disappeared for a period of three weeks. The insect reappeared with few number (8.7/10leaflets) on 22 of August then increased to form one peak on September 7th with an average of 50 individuals/10 leaflets (T. max. 34.2, T. min 25.2 oC and R.H. max. 82.2%, R.H. min 58.1%). The population correlated positively but not significant during the two seasons, while the correlation with min. R.H. during 2012 correlated negatively. 3.2. Population fluctuations of Empoasca decipiens (Paoli): For 2012 season, the population of Empoasca gradually increased until it reached its highest density on July 31st and August 21 including 26.3 and 27.7 individuals, respectively then decreased. During 2013 season similar trend was noticed. In 2012 season, the population correlated positively with two weather factors, while min. R.H. had negative correlation coefficient values. In season 2013, the population correlated positively with temperature, while R.H. parameters had negative correlation. 3.3. Population fluctuations of Nezara viridula: For 2012 season, the population of insects began in relatively low number (7insects/10leaflets) on 31of July, then the number increased and peaked on August 21st with (11.6 individuals/10 leaflets (T. max. 34.1 oC, T. min 25.1oC and R.H. max. 83.0%, R.H. min 51.8%) after that the population gradually decreased. During season 2013, the insect appeared for the first time with two individuals /10leaflets)on 7 of August. Generally the population was low (ranged between 1.3-3.3insects/10leaflets) and recorded its highest density on the 14th of August with an average of 3.3 individuals/plant (T. max. 31.5oC, T. min 24.8oC and R.H. max. 79.0%, R.H. min 56.7%). In 2012 season, the population correlated positively with all parameters and negatively with min R.H. In 2013 season, the weather parameters had positive correlation on population, while min. R.H. had significant correlation. 3.4. Population fluctuations of Melanagromyza phaseoli: In 2012 season M. phaseoli infestation appeared in relatively low numbers in July 10th, then fluctuated and peaked during August14including(4 larvae/10 leaflets, T. max. 36.2oC, T. min. 25.7oC and R.H. max. 86.7%, R.H. min. 50.1% and peaked again during September (2.3 larvae/10 leaflets, on 10th of September (T. max. 33.5oC, T. min 23.4oC and R.H. max. 86.2%, R.H. min. 53.2%). In 2013 season the larvae appeared on August 7th with 0.6 larvae/10leaflets,then population increased gradually and peaked on September 7th of with (30.7 larvae per sample) (T. max. 34.2oC, T. min 25.2oC and R.H. max. 82.2%, R.H. min 58.1%). M. phaseoli larvae correlated negatively in 2012 season but not significant. Min R.H. as it correlated positively. In the 2nd season the larval population correlated positively but not significant.