Effect Of Anti-transpirants On Growth And Yield In Soybean And Wheat

Anti-transpirants are chemical materials which can be applied on the transpiration surface of plant in order to restrain the water loss from transpiration. It includes 3 styles: Stomatal Closing Compounds, Film-Forming Anti-transpirants and Reflecting Anti-transpirants. Anti-transpirant is limited in applying on field crops due to its negative effects on environment. Recently supported by a 863 project, we developed several new kinds of anti-transpirant without toxicant. The effect of these new materials on crops is needed to be tested when compared with commercial one. The experiment was done from This study was conducted to test them.The experiment was done in the experimental base of the Chinese Academy of Agricultural Sciences in Beijing, China from June.2007 to Oct.2007 in soybean and Oct.2007 to June.2008 in wheat. The local soybean cultivar (Zhonghuang 33) was used in this study in 2007. Plant spacing was 20 cm and the row spacing was 45 cm. Seven treatments were carried out in this study; The local wheat cultivar (CA0045) was used in this study in 2008, And the row spacing was 30 cm. Six treatments were carried out in this study.The growth and eco-physiological characteristics had been determined during whole growth period of soybean and wheat, including photosynthetic rate, transpiration rate, stomatal conduction, relative leaf water content, chlorophyll content, biomass accumulation, yield and yield components. The results are as following: 1,In 2007, the photosynthetic rate, transpiration rate and stomatal conductivity in all materials showed obvious increase as compared with those in water treatment, indicating that all the testing anti-transpirants might have the positive contribution to soybean growth. The values obtained on 29 Aug. (10 days after spraying) were higher as compared those measured in other days.In 2008, the photosynthetic rate, transpiration rate and stomatal conductivity in all materials showed not such significant difference among treatmeats. The materials we used in 2008 were not exactly the same as we used in 2007, and also the plants were different too. These componds which did positive contribution to soybean growth may not act by the same way to wheat.2,In 2007, relative leaf water content and chlorophyll content of soybean were at the same level under different treatments. The same results were showed in 2008, which means without water stress the materials of anti-transpirant had not such positive contribution to the content of RLWC and chlorophyll in soybean and winter wheat.3,In the experiment of soybean, treatmen S1, S3 and S4 showed more dry matter accumulation in pod than other treatments. In treatment S1, S2, S3 and S4 ,the partition ratio of pod were higher as compared to other treatments. This might be one possible reason for the higher yield in these treatments. In 2008, treatments of all materials showed no significant difference in dry matter accumulation. Treatment W2, W3 and W5 showed more dry matter accumulation in weight of spike than other treatments. The partition ratio of weight of spike were lower in treatment WCK as compared with others.4,In 2007, the yields in all treatments with anti-transpirant of soybean were higher that that of water treatment. Treatment S1, S2, S3 and S4 had obvious higher yields as compared with others. The pod number and the total seeds number per plant may be the main reason of the higher yield of soybean.In 2008, treatments with anti-transpirant showed different effect on yield of winter wheat. We developed 4 kinds of anti-transpirant in 2008 which were not the same as the 5 kinds of anti-transpirant used last year on soybean. Treatments with new kinds of anti-transpirant showed higher yield compared with water treatment. The kernels of per spike may be the main reason of the increase of wheat yield.5,In 2007, the testing anti-transpirants all showed positive contribution to growth in soybean when soil water stress was not occurred. However, leaf applied with anti-transpirants did not show resistance in transpiration rate. The field water use efficiency increased in all treatments as compared with water treatment. In 2008, when soil water stress was not occurred, treatments with new kinds of anti-transpirant we developed showed higher yield compared with water treatment. The results in this study showed that the new developed anti-transpirants have positive impact on soybean and wheat growth when soil water is sufficient.