Variation in biological characteristics of purified pea ferritin (Fer) transgenic rice

Abstract After seven generations of self-crossing assisted by β-glucuronidase (GUS) detection, 26 homozygous transgenic rice lines were obtained. Transgene effects on iron content, agronomic traits, rice quality and stress tolerance were studied. The results indicated that the average iron content in the milled grain of the transgenic (pea ferritin, Fer) rice (Oryza sativa) was 10.37 μg/g among all the homozygous lines, and only four lines (Fer34, Fer36, Fer39 and Fer65) had significantly higher iron contents than that of the control, Xiushui11 (6.46 μg/g). Significant differences in main agronomic traits, such as days from sowing to heading, plant height, main panicle length, total grains of main panicle, seed setting rate, 1000-grain weight, and yield per plant were observed among some homozygous lines, but similar flag leaf length and number of panicles per plant were found. This showed that insertion of the foreign gene (Fer) had a slight impact on the main agronomic traits, but that the transgene had no negative effects. The quality traits of homozygous rice lines, such as the percentage of brown rice, milled rice and full milled rice, grain length, grain width, ratio of grain length and width, and amylose content were all similar to those of the control. However, variations were noticed in chalkiness, translucency, alkali spreading value and gel consistency among partial homozygous lines. Responses of homozygous lines to low and high temperatures were not significantly correlated with the iron contents, and resistance to rice blast (Pyricularia oryzae), bacterial blight (Xanthomonas oryzae) and brown planthopper (Niaparvata lugens) were enhanced with increased iron contents.