Aphids are considered one of the most economically important insect pests worldwide. Successful pest management systems are based on accurate and rapid pest species identification. Traditional morphological identification of closed aphid species may be considered an inaccurate taxonomic process. To overcome the disadvantages of traditional morphological identification, molecular techniques, related to DNA markers and based on polymerase chain reaction (PCR), were approached by using nine ISSRs primers to identify and diagnose fifteen common aphid species that disperse in the Egyptian agroecosystem. The examined ISSRs primers could success-fully discriminate the tested aphid species that reflected 61.39% polymorphism among them. Moreover, four banding patterns were considered unique bands that could characterize three aphid species (Aphis gossypii, Aphis nerii and Myzus persicae). The highest genetic homology (84.9%) was observed between species Rhopalosipum padi and Schizaphis graminum. In addition, each of A. gossypii and Aphis citricola were also genetically homologous species. In contrast, species Aphis craccivora and M. persicae were analogous genetically with a low similarity percentile (59.8%). High genetic di-vergence was observed also between A. nerii and M. persicae. Two alternative molecular branching taxonomic keys were proposed by subjecting the five highest polymorphic ISSRs primers and 29 banding patterns with different molecular sizes.

This paper aimed to examine the impact of climate change on wheat productivity in the five rains- fed districts: El-Negaila, Sidi Barrani, El-Daba'a, Marsa Matrouh, and EL-Alamain in the northern west coast of Egypt in which the cultivated wheat area represents about 41.4% of wheat area in Matrouh Governorate (1990-2019). The productivity is fluctuated between 1.167 to 13.38 Ardab/Fadden accompanied with the fluctuation in precipitation between 24.35 to 115.10 MM3/Season, and fluctuation of average difference between Max. Min. temperature from 8.07 to 7 ºC. Fully Modified Ordinary Least Square (FMOLS) technique was applied to investigate the relationship between wheat productivity and the independent variables (precipitation, temperature, cultivated area, labor and technology). OLS function showed that the model suffers from endogenity and heteroscedasticity. LLC and IPS statistics of panel unit root test proved that the included variables have unit root, i.e. they are non-stationary at level. Pedroni panel residual cointegration test confirmed the long run relationship between the first-order integrated variables [I (1)]. FMOLS function proved that natural climatic variables are the main determinants of wheat productivity, as a 1% increase in annual rainfall improves wheat productivity significantly by 3.3%, while temperature affects the wheat productivity negatively by 5.7%. The far west districts are the most affected by rainfall, as 1% increase of rainfall in EL-Negaila and Sidi- Barrani districts increase wheat productivity by 8.4%, 5.1% respectively. Results in all districts except EL-Negaila and Sidi Barrani showed the extent of labor intensification to enhance productivity, also all districts showed the importance of technical improvements. It is recommend adopting water policy as rain harvesting, building stone dykes and cisterns to provide: 355.5, 301.7, 287.9, 339.8, and 245.8 MM3/Fadden in El-Negaila, Sidi Barrani, EL-Daba'a, Marsa Matrouh, and EL-Alamain districts respectively to improve wheat yield to 12 Ardab/Fadden under drought climate of north coast