Preliminary Studies On Printing-sowing Key Technology With Applying In Non-heading Chinese Cabbage

The non-heading Chinese cabbage called Xiaobaicai(Brassica campestris ssp.chinensis Makino)origined from China,and is one of the most popular vegetables.Non-heading Chinese cabbage is cultivated with mixed soil,and the harvesting period is mainly concentrated on vegetable seedlings stage(also called Jimaocai).Due to the non-standard sowing technology,the seeds distributed uneven in the soil,resulting in the decrease of its uniformity for non-heading Chinese cabbage plants.The obove problems finally affected its appearance and commerciality.Therefore,it is essential for us to establish a new seeding technique for non-heading Chinese cabbage.Printing-sowing technology is a new technology developed in recent years.It has been successfully applied in rice breeding,but the application on vegetable cultivation has not been reported.In this experiment,we the non-heading Chinese cabbage variety ’Qinglan’ was used as material,and Jimaocai was taken as the harvesting form,we applied Printing-sowing technology to achieve even seeding of non-heading Chinese cabbage,and provided technical support for the application of Printing-sowing in vegetable cultivation.The main results are as follows:1.In order to explore the feasibility of Printing-sowing technology for non-heading Chinese cabbage,we used non-heading Chinese cabbage ’Qinglan’ as materials.Three experiments are as follows:(1)Printing-sowing paper materals screening and applying ways screening,The results showed that the tissue paper had adhered 4.310 seeds per cave,and the white paper had adhered 5.034 seeds per cave.The ability of the tissue paper to adhere seeds was significantly higher than that of white paper.The results also showed that the best treatment was facing soil,uncovered soil and tissue paper(T3),and it’s seedling rate was the highest.(2)Design test of roller template’s DoPP and IoPP.’DoPP’ means Diameter of Pore Points and ’IoPP’ means Interval of Pore Points.1600 plants/m2 was setted as seeding density So we designed two conbinations:A(DoPP 1.1mm,IoPP30mm),B(DoPP 1.4mm,IoPP40mm).The results showed that:the combination A adhered 1622 seeds/m2,the combination B adhered 1575 seeds/m2,both combinations are in accordance with the seeding density requirement.(3)Comparison test of seeding method in the same density,setting 4 combinations of mixed-soil spreading(CK1),liner spreading(CK2),combination A(A)and combination B(B),The results showed that the seedling rate and yields of CK were significantly higher than those of printing-sowing;there was no significant difference in growth index among treatments;the soluble sugar content of printing-sowing combination A was the best,while there was no significant difference in content of Vc,protein and nitrate among treatments.In summary,the two combinations are suitable for non-heading Chinese cabbage applying with printing-sowing technology,but they are needed to be improved.2.In order to explore the effects of different covering methods on the seedling and growth of non-heading Chinese cabbage,we used non-heading Chinese cabbage variety’Qinglan’ as material and we used tissue paper and combination B,setted up no cover(CK),single-layer of black shading net(B1),the double-layer black shading net(B2),single-layer white insect-proof net(W1),and the double-layer white insect-proof net(W2).The results showed that the white insect-proof net cover can significantly improve the seedling rate of non-heading Chinese cabbage printing-sowing.The single-layer white insect-proof net was the best in the autumn test,and the double-layer white insect-proof net was the best in the winter test;Shading net has a negative impact on the seedling and growth of non-heading Chinese cabbage.3.In order to propose a set of non-heading Chinese cabbage printing-sowing technical schemes with potential promotion and application value,we used non-heading Chinese cabbage variety ’Qinglan’ as material,and we used tissue paper.We setted 5 treatments in the experiment:conventional mixed-soil seeding technique(CK);combination A(DoPP1.1mm,IoPP30mm)+single-layer white insect-proof net cover(T1);combined A+double-layer white insect-proof net cover(T2);combination B(DoPP 1.4mm,IoPP40mm)+single-layer white insect-proof net cover(T3);combined B+double-layer white insect-proof net cover(T4).The results showed that the seedling rate of T1 and T2 was the highest.There were no significant differences in growth indexes among all treatments.The yield of T3 is significantly higher than CK,T1 and T2.The soluble sugar content of T2 and T4 was significantly higher than that of other treatments,and the nitrate content of leaves of T2,T3 and T4 was significantly lower than that of CK.The standard errors of the indicators of T1,T2,T3 and T4 are all smaller than CK,so the uniformity of non-heading Chinese cabbage which applied with printing-sowing is high.In summary,the printing-sowing has even seeding effect,and yield of the combination B+single-layer white insect-proof net cover is the highest,it’s even seeding effect is the most significant,and it can be applied as a set of non-heading Chinese cabbage printing-sowing technical scheme with potential promotion and application value.