Photosynthetic characteristics of sugar beet cultivars KWS0143 and Beta464 were studied under alkaline conditions, including 0 (A0, control), 25 (A1), 50 (A2), 75 (A3), and 100 mM of mixed alkali (Na2CO3:NaHCO3, 1:2). A2, A3, and A4 reduced net photosynthetic rate (PN), stomatal conductance, and transpiration rate, but rose intercellular CO2 concentration. Reduction in PN occurred probably due to nonstomatal limitation. The decrease in efficiency of photosynthetic electron transport might be the main reason for the decrease of PN. The concentrations of photosynthetic pigments were significantly reduced by high (A3 and A4) alkalinity. Changes in chloroplast ultrastructure are the reason for the decrease in chlorophyll content. Sugar beet could resist injury from alkali owing to osmotic substances and antioxidant enzymes if alkaline stress was at a lower level. The better performance of KWS0143 under alkalinity might be associated with its more efficient osmotic and antioxidant systems to resist injury of photosynthetic apparatus caused by alkalinity.

Iron deficiency is the most common nutritional disorder, affecting over 30% of the world's human population. The primary method used to alleviate this problem is nutrient biofortification of crops so as to improve the iron content and its availability in food sources. The over-expression of ferritin is an effective method to increase iron concentration in transgenic crops. For the research reported herein, sickle alfalfa (Medicago falcata L.) ferritin was transformed into wheat driven by the seed-storage protein glutelin GluB-1 gene promoter. The integration of ferritin into the wheat was assessed by PCR, RT-PCR and Western blotting. The concentration of certain minerals in the transgenic wheat grain was determined by inductively coupled plasma-atomic emission spectrometry, the results showed that grain Fe and Zn concentration of transgenic wheat increased by 73% and 44% compared to nontransformed wheat, respectively. However, grain Cu and Cd concentration of transgenic wheat grain decreased significantly in comparison with non-transformed wheat. The results suggest that the over-expression of sickle alfalfa ferritin, controlled by the seed-storage protein glutelin GluB-1 gene promoter, increases the grain Fe and Zn concentration, but also affects the homeostasis of other minerals in transgenic wheat grain.