Study On The Growth And Development Of Blueberry Improved By Organic Materials And Ground Cover Plants

Vaccinium Linn.also called blueberry,is a genus of perennial shrub or small tree of Ericaceae.Spring flowers are white and resemble lily of the valley.The new leaves are slightly red.The ripe berries in summer are purple or blue.After the autumn frost,the leaves turn into bright red,which has high ornamental value.Blueberry is the fruit with the highest content of anthocyanins except black currant.It is also rich in VC,VE,folic acid,etc.It has the functions of improving vision and anti-cancer health care.In the past ten years,with the increasing demand of the market,the cultivation area has also been expanding all over the world.Soil pH and organic matter content are important soil conditions that affect the growth of blueberry.The purple soil distributed in southwest regions have high pH value,low organic matter content,and high viscosity.They are not conducive to the growth of blueberry,limiting the industrial cultivation of blueberry in the southwest region.Blueberry is native to North America.In order to expand the planting area,researchers have continued to improve the soil in regions outside North America,through adding peat,sawdust,and moss to increase organic matter content,and sulfur to reduce soil pH.However,peat and other resources are limited and expensive,and the long-term use of sulfur will destroy the structure of soil.Therefore,it has become a new research direction to look for low-cost environmentally organic materials and plant materials to improve blueberry cultivation soil.This experiment uses the south highbush blueberries cv.‘Misty’as the test material,adding different proportions of coir dust,rot leaves and rapeseed straw to the purple soil,selecting Trifolium repens L.,Chlorophytum comosum(Thunb.)Baker,Polygonum capitatum Buch.-Ham.ex D.Don cultivated with blueberry.This study focused on the effects of organic and ground covers modificate the physicochemical properties of purple soil and growth of blueberry.The main research conclusion are as below:1 Effect of adding coir dust,etc.on physicochemical properties of purple soil1.1 Effect on soil pH:Adding different proportions of coir dust in purple soil,When the ratio of coir dust to purple soil is 1:4 and 2:3,soil pH is stable within the range of4.5-5.5,the pH are lower than CK;With the addition of rot leaves,there is no significant difference in the change of pH with the CK;the addition of rapeseed straw had higher pH than CK.The results show:In the effective reduction of soil pH,the effect of coir dust is better than that of rot leaves and rapeseed straw.When the added amount of coir dust does not exceed two-thirds of the volume of the purple soil,the pH can be stabilized within the range suitable for the growth of blueberry.1.2 Effects on soil Bulk density and Porosity:When the ratio of coir dust to purple soil is 3:2,the bulk density,TP,ATP,and WFP are 2.6%,155.7%,220.4%,148.2%of CK significantly higher than those of CK and other reatments;There is no significant difference between the treatments of rot leaves and CK;The bulk density,TP,ATP,and WFP at ratio of rapeseed straw to purple soil of 1:4 are 91.5%,112.9%,134.2%,110.4%of CK,significantly different from CK.Research indicates:When the ratio of coir dust and rapeseed straw to purple soil is 3:2 and 1:4,have the effects of reducing the bulk density and increasing the porosity of purple soil significantly,but the effect of rot leaf is poor.1.3 Effects on soil organic matter,etc:When the ratio of coir dust to purple soil is 3:2,the content of organic matter is 14.6%higher than that of CK,ignificantly higher than CK and other treatments;when the ratio is 1:4,the effective potassium content is 26.4%higher than CK,the difference is significant;when the ratio of the rot leaf to purple soil is 2:3,the content of organic matter and ammonium nitrogen are reduced by 18.7%and38.1%compared with CK,and the difference is significant;when the ratio of rapeseed straw to purple soil is 1:4,the ammonium is significantly higher than that of CK and other treatments,which is 119.7%higher than CK;the ratio is 3:2,the content of available phosphorus is 13.5%higher than CK,and the difference is significant.Research indicates:the contents of organic matter and N,P and K in purple soil could be significantly increased by adding coir dust and rapeseed straw,but the effect of rot leaf is poor.2 Effect of adding coir dust,etc.on growth and development of blueberry2.1 Effect on plant height,etc of blueberry:When the ratio of coir dust to purple soil is 2:3,plant height,and branches are 229.7%,and 127.3%of CK,significantly higher than CK and other treatments;When the ratio of rot leaf to purple soil is 2:3,the plant height and diameter are 65.3%and 94.8%of CK;when the ratio is 1:4,the crown width and branches are 80.4%and 72.7%of CK,the difference is significant.The ratio of rapeseed straw to purple soil is 1:4,diameter and crown width are 153.2%and 111.7%of CK,significantly higher than those of CK and other treatments.The results show:adding the ratio of coir dust and rapeseed straw to purple soil is 2:3 and 1:4 can significantly increase the growth of blueberry plant;rot leaf will cause the growth of blueberry to be hindered.2.2 Effect on leaf area,etc of blueberry:When the ratio of coir dust to purple soil is2:3,leaf area and dry weight of louver are 60.5%and 63.3%higher than that of CK,significantly higher than those of CK and other treatments;When the ratio of rot leaf to purple soil is 3:2,leaf area and soluble sugar content ae reduced by 12.6%and 25.1%compared with CK,the difference is significant.When the ratio of rapeseed straw to purple soil is 1:4,the chlorophyll and nitrogen content of leaf are are 16.9%and 20.0%higher than CK,significantly higher than CK and other treatments.Research indicates:When the ratio of coir dust and rapeseed straw to purple soil is 2:3 and 1:4,significantly promote leaf growth,increase dry matter accumulation and improve leaf quality of blueberry significantly;but the effect of rot leaves is not good.2.2 Effect on percentage fruit-set,etc of blueberry:When the ratio of coir dust to purple soil is 2:3,yeild of bush,ratio of sugar to acid,and total anthocyanin increase by149%,46.2%,and 10.9%compared with CK,significantly higher than those of CK and other treatments.When the ratio of rot leaf and purple soil is 2:3,the percentage fruit-set and yeild of bush are significantly below than CK;when the ratio is 3:2,the ratio of sugar to acid and total anthocyanin decreased by 49.9%and 20.9%compared with CK,and the difference is significant.When the ratio of rapeseed straw to purple soil is 1:4,the percentage fruit-set is 49.0%higher than CK,significantly higher than that of CK and other treatments.Research indicates:When the ratio of coir dust and rapeseed straw to purple soil is 2:3 and 1:4,significantly promote the development of blueberry fruit;and the effect of adding rot leaf is not significant.3 The difference in the roots H~+excretion capacity of 5 ground covers and‘Misty’under different pH treatmentsThe H~+excretion capacity of 5 ground covers and’Misty’is determined by dyeing method.The results showed:after pH 7.5 treatment for 3 days,visible yellow halos appeared around the rhizosphere of Polygonum capitatum Buch.-Ham.ex D.Don and Chlorophytum comosum(Thunb.)Baker and last until 14 days,with the largest range and darkest color;a small yellow halo around the roots of Trifolium repens L.and Tagetes erecta L.emerged after 3 days,and disappear after 14 days.Phlox drummondii Hook.and’Misty’are treated around the rhizosphere for 3 days and 14 days without obvious yellow appearing.The results of the solution method showed that:after 14 days of treatment at pH 7.5,the solution pH values of the five ground covers all decreased,and‘Misty’increased.The largest decline is in Polygonum capitatum Buch.-Ham.ex D.Don,followed by Chlorophytum comosum(Thunb.)Baker,Trifolium repens L.,Tagetes erecta L.,and Phlox drummondii Hook,which is consistent with the results of dyeing method.The results showed:the order of root H~+excretion capacity is Polygonum capitatum Buch.-Ham.ex D.Don,Chlorophytum comosum(Thunb.)Baker,Trifolium repens L.,Tagetes erecta L.,Phlox drummondii Hook.,‘Misty’.According to the results of the study,Polygonum capitatum Buch.-Ham.ex D.Don,Chlorophytum comosum(Thunb.)Baker and Trifolium repens L.are selected as the auxiliary plant cultivated with blueberry.4 Effects of Trifolium repens L.and others ground covers on growth and development of blueberryAfter two months of cultivating blueberry with two substrates and Trifolium repens L.,Chlorophytum comosum(Thunb.)Baker m and Polygonum capitatum Buch.-Ham.ex D.Don,the soil pH can be reduced from 6.6 to 4.5;and there is no significant difference between CK which is application of sulfur.The plant height,diameter,branchesz,leaf area,leaf chlorophyll,nitrogen and soluble sugar content of blueberry cultivated with Trifolium repens L.are not significantly different from those of CK;plant height and diameter and branches of blueberry supplemented with coir dust and Chlorophytum comosum(Thunb.)Baker are significantly better than those of CK and other treatments,which are 162.5%,106.4%,123.1%of CK,leaf area and dry weight of louver are 116.5%and 136.4%of CK,chlorophyll,nitrogen and soluble sugar content are 107.1%,108.8%and 146.9%of CK,significantly different from CK.The height,diameter,and leaf area of the blueberry supplemented with coir dust and Polygonum capitatum Buch.-Ham.ex D.Don are 34.9%,65.8%,and 79.9%of CK,and difference is significant.Research indicates:using substrate of ratio of coir dust to purple soil is 2:3,cultivated with Chlorophytum comosum(Thunb.)Baker can effectively reduce soil pH to replace part of sulfur,and promote the growth and development of blueberry plants and leaves.