Effects Of Organic Boron (GB) On The Growth And Development Of Soybean

Boron,as an essential nutrient element for plants,is one of the important factors limiting crop yield and quality.At present,the main ways of applying boron fertilizer are sprinkler irrigation and drip irrigation.However,in the actual production of water-soluble fertilizer,high concentration of boron precipitates easily with other elements.It is of great practical significance to increase the boron content of water-soluble boron fertilizer and reduce the precipitation.Organizing inorganic boron is an important technological measure to improve the boron content of water-soluble fertilizer.Organic boron and boric acid were used as test materials,and soybean was used as the test object.Pot culture,hydroponic and field test were conducted to figure out the difference between organic boron and inorganic boron.This study provides a theoretical basis for the research and development of organic boron fertilizer.The main conclusions of this paper are summarized as follows:?1?Soybean absorbed more organic boron than inorganic boron.When 1.8 mg boron was applied per kilogram of soil,the boron content of each part of the organoboron-treated soybean plants was higher than that of the inorganic boron treatment.At seedling stage,the boron contents of soybean roots,stems and leaves treated with organic boron?OBA?was 2.10 mg/kg,0.99 mg/kg and 1.71 mg/kg higher than that treated with inorganic boron?BA?,with the increase of 11.92%,8.36%and 4.78%,respectively.At maturity stage,the boron contents of soybean roots,stems,leaves,pods and beans treated with organic boron?OBA?were 1.36 mg/kg,0.31 mg/kg,4.15 mg/kg,1.69 mg/kg and 0.25 mg/kg higher than those treated with inorganic boron?BA?,with the increase of 10.62%,1.37%,4.43%,4.52%and 0.76%,respectively.When 6.9 mg boron was applied per kilogram of soil,the difference of absorption efficiency was greater,reaching a significant level.The hydroponic test which removed soil factors showed a similar trend.When the boron level was 0.5 mg/L,the boron contents of roots,stems and leaves of OB05 were 2.13 mg/kg,0.79 mg/kg and 3.92 mg/kg higher than those of B05treatment,with the increase of 16.09%,5.99%and 8.52%,respectively.When the boron level reached 5 mg/L,the boron contents of roots and leaves of OB50 treatment were 1.36mg/kg and 6.72 mg/kg higher than those of B50 treatment,with the increase of 3.41%and1.99%,respectively.?2?The content of reusable boron?free boron and semi-bound boron?in soybean treated with organic boron were higher than those treated with inorganic boron.The free boron,semi-bound boron and bound boron of leaves of organic boron treatment?OBA?were 0.11 mg/kg,0.01 mg/kg and 0.33 mg/kg higher than those of inorganic boron treatment?BA?when 1.8 mg boron was applied per kilogram of soil.The increase rates were 6.43%,1.13%and 14.67%,respectively.When 6.9 mg boron was applied per kilogram of soil,the contents of free boron and semi-bound boron of OBT were 2.26mg/kg and 0.33 mg/kg higher than those of BT,with the increase of 23.83%and 8.96%,respectively.The free boron content of OB05 and OB50 at the 10^th day were 0.18 mg/kg and 1.71 mg/kg higher than those of B05 and B50,respectively,with the increase of 9.77%and 6.29%.At the 30^th day,the free boron contents of OB05 and OB50 were 0.32 mg/kg and 0.46 mg/kg higher than those of B05 and B50,respectively,with the increase of 9.47%and 0.97%.?3?There was no significant difference in 100-bean weight between organic boron and inorganic boron treatments.When 1.8 mg boron was applied per kilogram of soil,there was no significant difference among the contents of protein,water,cellulose,fat,calcium,magnesium,iron and zinc between organic boron and inorganic boron treatments.When 6.9 mg boron was applied per kilogram of soil,the contents of protein and iron of organic boron treatment were significantly lower than those of inorganic boron treatment,but the fat content was significantly higher than that of inorganic boron treatment.There was no significant difference in other indicators.?4?Organic boron was more beneficial to the accumulation of root biomass than inorganic boron.Inorganic boron treatment?B05?had higher root length,surface area and bifurcation number than organic boron treatment,while average diameter of organic boron treatment was higher.The root biomass per plant of organic boron treatment?OB05?was 0.10 g/plant higher than that of inorganic boron treatment?B05?,with an increase of26.67%,reaching a significant level.This indicated that the roots treated with organic boron were thicker and less bifurcated,and had more biomass than those treated with inorganic boron.?5?Both of adsorption amount and desorption amount of organic boron in soil were higher than those of inorganic boron.This means that organic boron is less leachable in soil,and boron loss is reduced.The lag coefficient of desorption of organic boron is0.4791,which is less than 0.7352 of inorganic boron.Therefore,organic boron has better desorption reversibility and better aftereffect.?6?Compared with boron spraying at seedling stage,the effect of spraying at flowering stage was better.In the same spraying period,organic boron could improve the boron content in leaves more than inorganic boron and the mobility of boron to new organs was better as well.The boron content of leaves treated at seedling stage was measured at flowering stage,and the contents of free boron,semi-bound boron and bound boron of OBS treatment were still higher than those of BS treatment,increased by 0.60mg/kg,0.01 mg/kg and 0.22 mg/kg,respectively,with the increase of 12.63%,0.40%and4.19%.At maturity stage,the contents of free boron,semi-bound boron and bound boron of OBS treatment were 0.67 mg/kg,0.07 mg/kg and 0.27 mg/kg higher than those of BS treatment,increased by 15.20%,5.38%and 5.24%,respectively,and those contents of OBF treatment were 0.65 mg/kg,0.07 mg/kg and 0.17 mg/kg higher than BF treatment,with the increase of 14.20%,5.04%and 3.24%,respectively.In addition,by analyzing the quality indicators of soybean grains of the field test,the spraying period did not have a significant impact on them.