Evaluation of powdery mildew disease resistance of eight sugar beet varieties using agronomic traits and ISSR markers.

Abstract

his research aimed to evaluate some sugar beet varieties ( Beta vulgaris var. saccharifera , L.) to powdery mildew disease resistance. Eight sugar beet varieties namely 9K887 (Shantala)-KWS, Allanya-KWS, B8141 (BTS Smart 9175), Melodia, LP17B4011, FD18B4018, ST21801 (Mourad) and Zeppelin were planted under field condition during two seasons 2018/2019 and 2019/2020 at the Experimental Farm, Sakha Agriculture Research Station, Agriculture Research Center (ARC), Egypt. Growth and yield traits for foliage and roots were measured, economic traits; Total soluble solids (T.S.S. %) and sucrose content were estimated . Molecular differentiation was carried b y using six primers of inter simple sequence repeat (ISSR) markers. Results of studied traits showed significant differences among studied varieties. The varieties of B8141, 9K887 (Shantala) and Allanya had good characters; low percentage of disease severity, high mean values of foliage, root traits and high sucrose content in contrast with Zepplin, St21801, Mourad and FD18B4018 varieties. Results of Inter simple sequence repeat (ISSR) markers detect that technique was effectively differentiative produce 39 bands. Twenty-three bands were polymorphic with an average 58.97% polymorphism percentage. Polymorphic information content (PIC) ranged from 0.545 to 0.885 with an average of 0.772. Resistant varieties; Melodia, B8141, Allanya-KWS and 9K887 Shantala-KWS were distinct by presence of polymorphic band (165bp) produced by HB-8 primer. While sensitive varieties; Zepplin, ST21801, FD18B4018and LP17B4011 were distinct by the presence of two polymorphic bands; (175 and 945bp) produced by 89B primer. The highest value of similarity 0.97 was found between ST21801 and Zepplin. While the lowest value 0.66 was found between B8141 and FD18B4018 varieties. So, Cluster analysis classified the studied varieties into four clusters. There was great harmony between growth and DNA results.