From the editor
It is believed that soil properties will be changed by using chemical fertilizer for a long period, resulting in lower potential crop yield. Amnart Suwanarit and his colleagues studied changes in soil properties in 20 annual applications of ammonium sulphate and triple super phosphate for corn productivity on oxic paleustults soil. At the same time, he studied the effect of using groundnut and other green manure for replacing chemical fertilizer and found that this method should need more consecutive years of application to accumulate the benefit of green manure on corn productivity.
DNA technology can help or supplement conventional breeding on classification of genetic background of materials used. Meanwhile, endo-toxin of Bacillus thuringiensis (bt) strains found in Thailand has been studied for further development. Plantlet growth as well as plant regeneration is also important for gene technology study and plant genetic modification. Details and results of these studies are presented in this issue.
Teerasak Manupeerapan
Editor
Teerasakm21@hotmail.com