[Determination of nutrient elements in transgenic insect-resistant cotton tissues by three different spectroscopical methods].

In order to find out the effects of exogenous genes, such as Bt and Bt coupled with CpTI, on nutrition metabolism in transgenic plants, totally eleven types of nutrient elements in transgenic Bt (Z30) and Bt-CpTI (CCRI41 and SGK321) cotton were determined using methods of flame atomic absorption spectroscopy, flame atomic emission spectroscopy and spectrophotometry at flowering stage and boll-opening stage. The results showed that the chemical composition of plant nutrition in transgenic insect-resistant cotton differed in comparison with non-transgenic cotton counterparts related to varieties, tissues and stages. The content of total N in transgenic cotton changed most significantly.

[Amelioration effect of sand-fixing Hedysarum fruticosum plantations on soil nutrient contents and biological activities].

With adjacent semi-moving dune as the control, this paper studied the effects of 5-, 10- and 22-year old Hedysarum fruticosum plantations on the nutrient status, microbial biomass, and enzyme activities at the soil depths 0-10, 10-20 and 20-30 cm. The results showed that with the establishment of H. fruticosum plantation on moving dune, soil C, N, P and K contents and biological activities increased obviously with the increasing age of the plantation, and the increment was much higher at 0-10 cm than at 10-20 and 20-30 cm.