Effects Of Foliar Spraying With Wood Vinegar And Its Compound On The Growth And Yield Of Rapeseed

Wood vinegar is the acidic yellowish-brown liquid produced by further cooling and reflux of flue gas from burning agricultural and forestry wastes.It is widely used in agricultural production because it has similar properties as the plant growth regulator,besides the production materials are simple and easy to obtain.It was demonstrated that wood vinegar could increase the production of many crops by improving plant photosynthesis and stress resistance,but less research has been done on canola.Therefore,it is of considerable significance to carry out the application and basic theoretical research of wood vinegar on canola,to promote the green and efficient cultivation of canola,and to study the influence mechanism of wood vinegar on canola growth.In this study,we chose a major cultivated rapeseed variety(HUAYOUZA NO.9)as the research material and treated canola using Poplar wood vinegar.At first,to find the appreciate concentration for the application in canola production,we conducted a seeding experiment in the pots and treated seedlings with spraying different concentration wood vinegar at the 3-leaf stage and 8-leaf stage,respectively.Secondly,to screen the reasonable formula of wood vinegar and hormone compound,we conducted a pot experiment and a field over a growing season.We sprayed canola by mixing wood vinegar with GA,Sodium D-gluconate,Melatonin,2-4-D,6-BA,and Ethrel in the pot and field experiments at the seedling stage and wintering stage.The results of the seeding experiment showed that spraying vinegar solution diluted300 to 500 times can increase root dry weight by 3.04-41.98%,stem dry weight by 35.74-68.27%,dry leaf weight by 19.80-55.90%,total dry weight by 27.14-57.02%.At the same time,it can increase the plant height,root neck thickness,maximum leaf length,maximum leaf width,leaf area,and specific leaf weight.It should be emphasized that spraying vinegar solution diluted 400 times has the most apparent effect on canola growth,and the leaf area increase by 50.97-85.53%compared with CK,but spraying vinegar solution diluted 10 to 50 times can inhibit the growth of canola.Compared with different spraying periods,the three-leaf spraying treatment had more apparent effects on the growth of roots,stalks,and leaves,while the eight-leaf spraying treatment had a less promoting effect on roots.Besides,wood vinegar treatment can reduce the root and shoot ratio.The results of pot and field experiments during the whole growth period showed that the effective branch number,effective pod number,biomass,plant height,rhizome diameter,total leaf number,green leaf number and leaf photosynthesis of each plant under M treatment increased.The leaf area of each plant increased by 44.11%,and the leaf area index increased by 30.74%,respectively.At the low temperature of 2-6?in the bud stage,wood vinegar solution treatment can significantly increase the proline content by 167.42%,the content of peroxidase by(SOD)20.98%,and the net photosynthetic rate by 16.19%in the flowering stage.Finally,the economic yield per plant of rapeseed was 14.77%higher than that of the CK,and the field yield reached 2172.4 kg/hm~2,which was 10.41%higher than that of the CK.The treatment of T1,T2,and T3 in the compound of wood vinegar were better than that of wood vinegar alone.Among them,T1 had the best growth-promoting effects on canola.The economic yield per plant was 9.74%higher than that of treatment M,and the field yield was up to 2375.10 kg/hm~2,which was 9.33%higher than that of treatment M.In summary,spraying wood vinegar diluted by 300-500 times at the three-leaf stage and eight-leaf stage seedlings can significantly increase the plant height,root diameter,leaf area,and leaf weight and biomass of canola.Generally,it is better to apply the wood vinegar solution with 400 times diluted concentration at the three-leaf stage.The leaf area and photosynthetic rate of canola could be improved by spraying diluted 400 times of wood vinegar during seedling and overwintering period,the resistance to the low temperature of canola also could be improved,besides the aging rate of leaves in the flowering period was delayed,which was conducive to the accumulation of dry matter and the transport to bearing organs.The wood vinegar solution increased the number of effective branches and pods of canola and increased the yield of canola by increasing the source and expanding the reservoir.In the compound of wood vinegar,the indexes of the mixture of wood vinegar and Gibberellin were significantly better than that of the compound of wood vinegar and Gibberellin.