Effects of Stem-leaf Returning on Physic-chemical Properties of Soil and Growth Performances of Next-cropping Pineapples
A field experiment was conducted to investigate the influence of shattered stem-leaf returning directly(RD) on the physic-chemical properties of soil and the growth performances of next-cropping pineapples.The obtained results indicated that bulk density of soil was decreased by RD treatment.Contents of organic matter,available P and available K of soil were increased in some degree when compared with the control.The activities of urease,catalase,acid phosphatase and invertase of soil were strengthened.In particular,significant difference was observed in acid phosphatase and invertase when compared with the control.RD treatment increased the population of bacteria and actinomycetes in soil.But the population of fungi was decreased when compared with the control.RD promoted the growth of next-cropping pineapple plants.The growth characteristics such as plant height,leaf length,number of green leaves,number of roots,and root length as well as the weight of aboveground and underground were higher than those of the control.The contents of chlorophyll a and chlorophyll b were increased.The contents of soluble sugar and protein of leaf were both significantly increased by RD treatment.And also,the vigor of the roots of pineapple of RD was markedly higher than that of the control.RD promoted the growth of pineapple fruits with increasing the transverse diameter,longitudinal diameter,weight per fruit and yield.