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In this research, reliability for disease severity assessment was compared for two different digital imaging quantifying techniques (ImageJ and Leaf Doctor applications) and visual assessments included ImageJ (IJ), Leaf Doctor (LD) applications, and visual assessments (VA) for the downy mildew of lettuce and Cercospora leaf spot of chard. Samples of infected chard leaves with symptoms of Cercospora leaf spot disease and lettuce leaves with symptoms of downy mildew were randomly collected from a field and a grocery in Al Anbar Governorate, Iraq. Each leaf was shot with iPhone 8 plus, provided with Dual 12 MP Camera, f1. 8, 28mm (wide), and f 2.8 (telephoto). The percentage of the diseased tissue of each shot was subjected to visual analysis and the ImageJ (IJ), Leaf Doctor (LD) applications. The measurements for them were subject to statistical analyses. Generally the results revealed a compatibility in the performance of the evaluated methods for the both diseases. There was positive and significant correlation coefficients between the measurement results of the VA and the LD for the downy mildew of lettuce (r= 0.664 ) and the Cercospora leaf spot of chard (r = 0.8990 ). Regarding the correlation between the IJ measurements and that of either VA or the LD revealed to be weak for both diseases. There were also linear regressions obtained only between the VA and the LD measurements (R2 = 0.441 for downy mildew and R2 = 0. 809 for Cercospora leaf spot). The results of other experiment indicated positive correlation coefficients between the upper and lower disease severity measurements regardless the assessments methods for both diseases. The highest correlation coefficients and linear regression were found for the AV measurements (r =0. 936, R2 = 0.876 and r = 0.996, R2 = 0. 992 for lettuce and chard respectively) followed by that of the LD (r = 0.908, R2 = 0.824 and r = 0.835, R2 = 0.697 for lettuce and chard respectively). This research indicates that the LD application is easier, faster and more reliable and accurate for disease severity measurements regardless the disease and its severity.

The Red Palm Weevil (RPW) Rhynchophorus ferrugineus (Olivier) is well-known as serious insect pest of date palm and other palm species. The pest was firstly recorded in Iraq in 2015. This study was confirmed the identification of this pest using molecular diagnostic (PCR and sequence analysis) and investigate the genetic relationship by comparison of the sequences with other recorded copies worldwide. The results confirmed the identity of the R. ferrugineus (Olivier) molecularly. Ten copies of mitochondrial COI gene of Iraqi samples (MF092880.1- MF092889.1) were firstly registered in National Center of Biotechnology Information (NCBI). The sequences comparison of Iraqi sample genes with worldwide genes showed high similarity with Chinese and Mediterranean COI copies especially the Tunisian one, which may assumes that they were descended from the same origin. The study concluded that the invention of this insect to Iraq could be occurred directly from farms in border area between Iraq and Kuwait or by infested offshoot that imported from other countries.

Wilt death disease on date palm tissue culture offshoots is a new interested phenomenon observed in Iraq since a several years, represented by fungal disease infecting plants in pots and/or soil, causing graduate wilt starts from down fronds to the top, ending with death.  The survey results revealed that infection percentage ranged from 4% in Abulkhaseeb district to 4.5% in Al-Seeba area with no significant differences among infected orchards (P-0.369), while the death percentage was 6.2% in Al-Seeba area comparing with 2.4% Abulkhaseeb with no significant differences too (P=0.368). The isolation results confirmed that Fusarium solani was the main isolated fungus from all root samples. Five isolates of F.solani (MLA5, MLA6, MLA7, MLA9 and MLA10) were identified at morphological and molecular levels then deposited in NCBI gene bank under the registration numbers (MG932641.1-MG932645.1). The present study recorded F.solani as a causal fungus of wilt and death disease on date palm tissue culture offshoots for the first time in Iraq.

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