Effect Of Soil Compactness On Growth And Physiological Characteristics Of Ginger

The change of soil compactness influenced not only the soil physical character but also root's penetrate resistance, soil water content, soil air permeability and water fertilizer utilization etc, so, there is different productivity in different soil compactness. Therefore, this paper studied that soil compactness affected on growth, yield, quality and primary characteristics of ginger plant in order to ravel mechanism of soil compactness effect on ginger growth and provided theories foundation for superior quality high produce and soil improvement."Laiwu big ginger"was used in this paper, this experiment had three soil treatments according to soil bulk density ( T1:1.49 g/cm³,T2:1.36 g/cm³,T3:1.20 g/cm³)and studied effect on ginger growth, yield of soil bulk density and the changes of physiology bio-chemical of ginger. The experimental results were listed below:1. Compacted soil could restrain the growth of ginger plant. The soil of low bulk density, which had larger soil porosity and higher maximum water hokling capacity, could obviously promote the growth of ginger, and improve yield. The plant height, stem diameter, branch and leaf number of T3 were higher than T1 by 17.9%, 14.0%, 31.7% and 36.1% respectively in their final growth stage. The fresh weight of root, stem and leaf were higher by 43.3%, 24.4% and 28.1%. The yields of CK, T1 and T2 were 2534.2, 3017.7 and 3326.8kg/667m2 respectively at harvest.2. The soil compactness had a significant effect on the quality of ginger. The content of rhizome dry matter, starch and volatized oil went up with the increase of soil bulk density. The content of rhizome dry matter and starch of T1 were higher than these of other treatments, the content of dry matter of T1 was higher than these of T2 and T3 by 6.9% and 11.3%, the content of starch was higher 13.4% and 27.6%, the content of volatized oil was higher by 10.5% and 24.7%. On the contrary, the content of protein and amino acid decreased. The content of protein of T2 and T3 were higher than these of T1 by 49.3% and 53.0%, the content of amino acid were higher by 42.9% and 57.1%. The change of soil bulk density had little effect on the content of fiber, sugar and Vc.3. Compacted soil could accelerate senescence of ginger plant. Activity of roots reduced when soil compactness increased. The roots activity of T2 and T3 were higher than T1 by 11.9% and 20.3% at their highest point. NRase activity and chlorophyll content declined when soil compactness increased. T2 and T3 were higher than T1 obvisously in metaphase and anaphase.The NRase activity of T1,T2 and T3 were 295,339 and 381μg·g^-1·h^-1 on 30th Aug. The chlorophyll content of T2 and T3 were higher than T1 by 13.2% and 23.5% on 29th Sept. Electrolytic leakage and MDA content improved when soil compactness increased. Electrolytic leakage of T1,T2 and T3 were 20.2%,18.4% and 15.2%, MDA content were 12.3,11.0 and 10.2 nmol·g^-1·FW at their bloom growth period. SOD, POD, CAT activities reduced with soil compactness increased in prophase growth of ginger, but it was contrary in anaphase growth of ginger.4. The soil compactness affected ginger's photosynthesis and fluorescence ability. When soil compactness increased,photosynthetic rate, Gs, Tr and LWUE decreased. The photosynthetic rate of T1,T2 and T3 were 10.8, 13.0 and 14.0μmol·m^-2·s^-1 at their bloom growth period, T2 and T3 were higher than T1 by 20.4% and 29.6%. However, Ci and Ls increased. Light saturation point, CO₂ saturation point and apparent quantum yield(AQY), carboxylation efficiency(CE) decreased, light compensation point and CO₂ compensation point augmented. The Fv/Fm,ΦPSII and qP of ginger were also decreased.