No abstract

ABSTRACT. In this study, 2 approaches were adopted to obtain good single-strand conformation polymorphism (SSCP) data for autotetraploid alfalfa; primers were added to PCR products, and fluorescent-labeled primers were utilized. PCR-SSCP conditions for a 331-bp fragment in the coding region of polygalacturonase-inhibiting protein gene 2 in alfalfa (MsPGIP2) were optimized, and the results showed that the best SSCP gel pattern could be obtained when the loading mixture was made by mixing 1 µL PCR products, 0.2 to 0.8 µL unlabeled primers (50 µM) and 4 to 16 µL loading buffer. Furthermore, the use of the fluorescent-labeled primers resulted in 2 separated electrophoresis images from 2 complementary single DNA strands, thus making the determination of alleles and idiotypes a relatively easy task. In addition, the results of sequencing prove that the determination 10185 ©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 13 (4): 10184-10193 (2014) Detecting the alleles of MsPGIP2 by improved SSCP technique of alleles and idiotypes were accurate based on SSCP analysis. Finally, a total of 9 alleles with 18 SNP sites were identified for MsPGIP2 in the alfalfa variety 'Algonquin'. In conclusion, MsPGIP2 possessed great genetic variation, and the addition of primers to the PCR products in combination with the fluorescent labeling of primers could significantly improve the sensitivity and resolution of SSCP analysis. This technique could be used for genetic diversity detection and marker-assisted breeding of useful genes in autopolyploid species such as alfalfa.

In order to explore the effect of using two different afforestation tree species to improve soil in coastal saline-alkali land, the method of combining field sampling and indoor analysis and test was adopted. The physical and chemical properties of soils planted with Rhus typhina and Robinia pseudoacacia forest were determined. The results showed that afforestation could improve soil structure, decrease soil bulk density and increase soil fertility. To reduce soil salinization, the soil physical and chemical indexes of Robinia pseudoacacia plantation were better than those of growing Rhus typhina forest, so the planting area of Robinia pseudoacacia plantation in Dagang area could be increased. Planting Rhus typhina forest could also improve the soil in this area, but its effect was lower than planting Robinia pseudoacacia plantation.

In order to obtain the embryogenic callus of raspberry, the friable calluses of raspberry were used as materials to be treated by different time of starvation and desiccation, and were further cultivated and induced embryoid. By use of embryogenic observation, the embryogenic degree of callus could be determined. The results showed that the embryogenic degree of calluses which were treated by starvation for 6 days was the highest, and the desiccation treatment had no effect on embryogenic degree of calluses. Therefore, appropriate starvation treatment can facilitate the transformation of non-embryogenic callus into embryogenic callus. The results of this experiment could provide reference for callus embryogenesis induction of other plants.