Abstract
Wastes of pig, chicken and cow were sampled during composting process under the conditions of high temperature and forced aeration. Water-extracted solutions of the sampled composts were added to the agar culture solution of Solanum and Stewartia pollen to see the elongation reaction of the cultivated pollen tubes.
Contents of total nitrogen in naturally wind dried matters of pig and chicken were high (2.09 to 3.43%), while that of cattle was about 1.73%. Correlation coefficients between the lengths of the cultivated pollen of both sources and concentrations of NH4-N were negatively high (R2=0.59 to 0.80). NH4-N contents in the cow composts increased gradually with the progressing of composting. The fact that pH values of composts were all above 7.57, proved few amount of acids produced. There existed a positive high correlation coefficient between EC and NH4-N of the composts, showing that most of salts were NH4-N ions.
Therefore, it can be said that the gradual tone of suppression on the elongation of the cultivated pollen tubes was mainly due to the tendency of NH4-N in the composts. It proved that bioassay of pollen tube is useful for the evaluation of compost maturity.
