Effects Of Different Substrate Proportion And Fertilizer Amount On The Growth And Development Of Non-heading Chinese Cabbage

Non-heading Chinese cabbage（Brassica rapa ssp.chinensis）is a one-year or two-year-old leafy vegetable crop.The leaves are rich in minerals,vitamins,anthocyanins and other nutrients.It not only has a short growth cycle,is highly adaptable,and is also economical.The characteristics of high efficiency and high output occupy an irreplaceable position in the supply of vegetables in the market.With the improvement of people’s living standards and the rapid development of protected agriculture,non-heading cabbage is favored by more and more consumers and growers.The huge market demand has made the application of large-scale substrate cultivation more and more extensive,and the demand for common substrates such as peat and vermiculite is also increasing.However,due to its high price and non-renewable nature,many scientific researchers are now committed to develop other new cultivation substrates to reduce or replace peat as a cultivation substrate.In this experiment,"Purple Crown"non-heading cabbage was used as the experimental material.Coconut chaff and grass charcoal were mixed in different volume ratios,and then a certain amount of vermiculite and perlite were added to screen the best substrate ratio for cultivation of"Purple Crown",finally,add different amounts of new fertilizer-soy fertilizer according to the best substrate ratio,explore the most suitable fertilizer amount under the best substrate ratio,and compare the various substrate formulations by measuring the agronomic characteristics and agronomic quality of"Purple Crown".Comparing the pros and cons of fertilization,the results are as follows:The test results of the growth and development of"Purple Crown"non-heading cabbage with different substrate ratios show that the"Purple Crown"items of T3 treatment（grass:coconut bran:vermiculite:perlite=4:4:1:1）,the values of agronomic traits,physiological indicators,agronomic quality and gene expression related to anthocyanin synthesis are the highest.The growth trend of agronomic traits of"Purple Crown"is more obvious,in which plant height,stem thickness,root length,maximum leaf area,whole plant fresh weight and dry weight increased by 20.6%,24.9%,43%,39.2%,67.7%and 61.5%,respectively compared with the CK group.The physiological indexes of"Purple Crown"are also at their maximum,among which the root activity reaches 326.01 mg·g^-1·h^-1,the DPPH free radical scavenging rate is 62.5%,the total chlorophyll concentration is 48.97mg/L,and the total carotene concentration is 13.17 mg/L.The various agronomic qualities of"Purple Crown"are also relatively high,soluble protein content is 17.52 mg/g,soluble sugar content is 25.32 mg/g,vitamin C content is 62.24 mg/100g,anthocyanin is 78.83mg/100g,and the expression levels of genes related to anthocyanin synthesis were higher than those of other groups.In summary,"Purple Crown"non-heading Chinese cabbage is most suitable for growing in the cultivation substrate of grass charcoal:coconut chaff:vermiculite:perlite=4:4:1:1,and the p H of this group of substrates is 6.69 and EC value is637.52μs/cm,the bulk density is 0.57 g/cm³,and the total porosity is 83.16%.The values are all within the range of the most ideal cultivation substrate.Therefore,it can be recommended as a coco peat cultivation"purple crown"non-heading cabbage to reduce grass charcoal use the best matrix ratio of the amount.The effect of different fertilization rates on the growth and development of"Purple Crown"non-heading Chinese cabbage showed that the various agronomic characteristics,physiological indexes and agronomics of"Purple Crown"non-heading Chinese cabbage in group F4（soybean fertilizer:substrate=3:7）.Both the quality and anthocyanin-related gene expression were the maximum.Soybean fertilizer has obvious promoting effect on the agronomic traits of"Purple Crown"non-heading Chinese cabbage.The plant height,stem thickness,root length,maximum leaf area,fresh weight and dry weight of"Purple Crown"in group F4 are respectively higher than those in CK group.The increase was 31.46%,21.96%,47.1%,28.26%,21.6%and 45.3%.Under the treatment of F4 group,the various physiological indexes of"Purple Crown"were relatively high.Among them,root vigor increased by 38.1%,DPPH free radical scavenging rate increased by 4.48%,total chlorophyll content increased by 35.67%,and total carotene content increased.That’s35.56%.The agronomic quality of the"Purple Crown"cultivated in the F4 group is also relatively high.The soluble protein content has increased by 27.22%,the soluble sugar content is not the maximum,but it has also increased by 11.35%,and the vitamin C content has increased by 22.5%.The anthocyanin content increased by 22.49%,which significantly increased the content of the functional compounds of"Purple Crown",and the expression values of genes related to anthocyanin synthesis were higher than those of other groups.In summary,the fertilization rate of F4 group is the best fertilization rate for"Purple Crown"non-heading cabbage cultivation,and the substrate p H of this group is 6.58,EC value is876μs/cm,bulk density is 0.713g/cm³,total porosity is 76.93%,and the physical and chemical properties are all within the ideal cultivation substrate.Therefore,a new type of soybean fertilizer with a ratio of fertilization to substrate volume of 3:7 can be recommended as the best fertilization for non-heading Chinese cabbage,and coconut bran as the main substrate for cultivation.