Effects Of Exogenous Selenium Fertilizer On The Growth Of Two Common Forages

In order to study the effect of selenium on forage growth,alfalfa(Medicago sativa L.)and chicory(cichorium intybus L.)were used as research objects in this paper.according to the level of selenium-enriched soil in China,the effects of different concentrations of inorganic and organic selenium fertilizers on forage growth and soil were studied by applying inorganic selenium fertilizer-sodium selenite and organic selenium fertilizer-selenomethionine based on pot experiment.The results were as follows:1.Application of different kinds of exogenous selenium fertilizer can significantly improve the germination rate of forage(p<0.05),and it will be increased with the increase of exogenous selenium concentration;The stem/leaf ratio of alfalfa with medium concentration of exogenous selenium was higher than that of the control and other concentrations,and the leaf/stem ratio was the highest 114.70%.Exogenous selenium had no significant effect on plant height and aboveground biomass of forage grass.Among them,the application of organic selenium fertilizer had a good effect on the growth of grass.2.Application of exogenous selenium fertilizer with different concentrations could significantly increase the content of crude protein,crude fat and crude ash of forage(p<0.05),and it was increased with the increase of exogenous selenium concentration.When sodium selenite was applied,the content of crude protein and crude fat in forage was higher than that of selenomethionine,and the maximum content of crude protein in alfalfa and chicory was 19.43% and 21.02%,respectively.The maximum crude fat contents of alfalfa and chicory were 7.74% and 2.66%,respectively.The crude ash content of alfalfa reached a maximum of 18.14% when selenomethionine was applied,and that of chicory reached a maximum of 15.97% when high concentration sodium selenite was applied.Among them,the application of inorganic selenium fertilizer had a good influence on the nutritional quality of forage.3.The application of exogenous selenium fertilizer can significantly increase the total selenium and inorganic selenium content of forage(p<0.05),and it will be increased with the increase of exogenous selenium concentration.Application of above medium exogenous selenium fertilizer can make the forage meet the seleniumenriched forage standard.The effect of sodium selenite on total selenium and inorganic selenium content of alfalfa was higher than that of selenomethionine,with the maximum values of 0.2335 mg/kg and 0.1471 mg/kg,respectively.The total and inorganic selenium contents of chicory when selenomethionine was applied were higher than that when sodium selenite was applied,the maximum values being 0.1711 mg/kg and0.1411 mg/kg,respectively.Application of exogenous selenium fertilizer could increase the organic selenium content of forage grass,and with the increase of exogenous selenium concentration,the organic selenium content also increases.Among them,application of medium and high concentration exogenous selenium fertilizer could significantly increase the organic selenium content of alfalfa(p<0.05),and high concentration selenomethionine could significantly increase the organic selenium content of chicory(p<0.05).With the application of exogenous selenium fertilizer,the organic selenium conversion rate of alfalfa increased with the increase of application concentration,but chicory decreased with the increase of application concentration.The conversion rate of organic selenium in feed with selenomethionine was higher than that with sodium selenite.4.The effect of exogenous se fertilizer on the soil planted with different forage grass is quite different.Application of exogenous selenium fertilizer improved the organic matter in the soil where chicory was planted,but the difference was not significant with the control(p>0.05).The total phosphorus content in the soil planted with alfalfa when exogenous selenium fertilizer was applied was significantly lower than that of the control(p<0.05).When inorganic selenium fertilizer sodium selenite was applied,the soil p H of alfalfa planting area decreased but the change was not significant(p>0.05).Exogenous selenium fertilizer can promote the absorption of phosphorus by plants,but has little effect on the physical and chemical properties of other soils.