Field Screening Of Recombinant Inbred Lines (Rils) Of Quinoa (Chenopodium Quinoa Wild.) For Resistance To The Pests

Quinoa (Chenopodium quinoa Wild.) cropping is very successful in Morocco. A breeding program was set up for 22 years ago to develop adapted, productive germplasm. Success of quinoa cultivation requires not only suitable germplasm but also sound production practices, including control of harmful pests that are likely to cause yield losses. The aims of current study were to (i) establish an inventory of quinoa pest’s species in five contrasting agroclimatic sites; (ii) assess the severity of pest damage; and (iii) screen 156 RILs for resistance to the predominant pests. Two trials were carried at Berrechid and Tiflet in 2017-2018, with three others at Bouchane, Meknes, and El Kebab in 2018-2019. The experimental design was a randomized complete block with four replicates. The insects were collected and inventoried during both experimental years. The pest impact was assessed through the percentage of injured leaf area at three heights of plant foliage, apical, median, and basal. The inventoried insects belonged to eight species and six orders. Aphis fabae, Myzus persicae (Homoptera) and Nezara viridula (Hemiptera), were classified as the most frequent species. Utetheisapulchella and Spodopetraeridani (Lepidoptera), were the least abundant. Tiflet and Berrechid recorded occurrences averaging 19.64 and 15.73%, respectively. Bouchane, Meknes, and El Kebab expressed an outbreak rate of 5%. ANOVA revealed very significant differences among sites, lines and, their interaction. The two-dimensional PCA graph identified four clusters. The PC1 axis gathers 64.34% of the total variability while the PC2 axis explains an additional 24.01%. The AMMI analysis revealed highly significant effects of the site, the genotype, and their interaction. The G×E explained 46% of the total variation, while the experimental site accounted for 28% and the genotype 26%.The examined RILs showed segregation for resistance and ranked from the most sensitive to the most resistant, such the C. berlandieri parent.