Effects Of Continuous Cropping On Growth And Physiological Characteristics In Cotton And Regulating Effect Of Sulphur Fertilizer On Continuous Cropping

In this experiment, Shuo-Feng738was useing as material. Through the researchedby morphological, physiological and biochemical indicators of cotton on cropping andnon-continuous cropping, to showed up the effect of continuous cropping influence onthe growth, development of the cotton; through the researched by influence of differentamounts of sulfur fertilizer on biomass and yield of cotton on cropping cotton field, toshowed up the regulatory effect of Sulfur fertilizer on continuous cropping; through theresearched of the influence of cotton seedling growth and development by the three mainallelochemicals in cotton humus: linoleic acid, palmitic acid and dibutyl phthalate, toshowed up the influence of Allelochemicals on the growth, development of the cottonseedling. In order to reduced the continuous cropping barrier, which provides the theorybasis to the continuouce production of cotton. The main results were showed as follow:1. The continuous cropping has the obvious adverse effect on the cottons growth.Consequently, plant height and stem diameter decreased, the quantity of fruit branchesand fruit nodes decreased, the abscission quantity and abscission rate of squares and bollswere increased, the quantity of fruit nodes and ratio of bolls on the upper fruit brancheswere decreased, the ratio of diameter in distal and proximal decreased, the soluble sugarcontent decreased, the Proline content and Malondialdehyde content increased,Peroxidase activity increased. Continuous cropping increased the expulsion rate of bolls,decreased the physiological activity and membrane structure stability of cotton functionleaf, decreased the photosynthesis and yield formation.2. The continuous cropping obvious decreased the dry matter accumulation, andincreased the distribution proportion of reproductive organs. In full-bloom stage, Thecontinuous cropping decreased the leaf nitrogen distribution proportion and ground shootpotassium distribution proportion, increased the reproductive organ nitrogen andpotassium distribution proportion. In boll opening stage, the continuous croppingcontinuous cropping decreased the nitrogen phosphorus and potassium accumulation, ofthe leaf and reproductive organs, but increased the nitrogen and potassium distribution proportion of reproductive organ.3. The influence to quantity and lint percentage of pre-summer bolls and summerbolls by continuous cropping were not obvious, but decrease the single boll weight. Thecontinuous cropping decreased the quantity and lint percentage of autumn bolls, lead tothe yield reduction,2011decreased by9.72%,2012decreased by7.52%.4. In the high concentrations, Linoleic acid, Palmitic acid and Dibutyl phthalateinhibited the cotton seedling growth, which include the growth of cotton shoots and rootand decreased root activity, at the same time, they increased superoxide dismutase andhydrogen peroxide activity, and the MDA content. The growth of had improvement in thehigh concentrations.5. Sulfur fertilizer can increased the reproductive organ nitrogen phosphorus andpotassium accumulation and every organ potassium accumulation. Proper concentrationsof sulfur fertilizer increased the quantity of summer bolls, the result of the quatity of totalbolls improvement lend to the output increased. Low concentration of sulfur fertilizerwas increased by10.64%in2011, low concentrations of sulfur fertilizer treatment and ahigh concentration of sulfur fertilizer treatment were increased by5.66%and4.07%.Showed that amount of sulfur fertilizer can contribute to the yield increased, the yieldreached98.89%and97.72%of non-continuous cropping in two years,can reduced theadverse effect to the yield significantly which caused by the cotton continuous cropping.Although high concentration of sulfur fertilizer increased the yield, but theyield-increasing effect declined.