Preliminary Application Of Vermicompost Compound Substrate In Marigold Seedling Production And Cultivation

With the rapid development of intensive, scaled and commercialized breeding industry, the production of fecal waste has increased dramatically and become the major resource of organic agricultural solid waste. The technology of decomposing organic waste using earthworms is advancing. It has been used to treat cow dung in various degrees. To decompose cow dung using earthworm has an advantage over traditional composting in that the product is clean and odorless. Vermicompost, the product of digestion, is an substrate for soilless cultivation thanks to its excellent physical, chemical and biological characteristics. The increasing cultivation of Marigold, an important ornamental and medicinal flowers, demands high amount of cultivation substrates. Currently the major substrate used is peat, which is non-renewable. Therefore, it is urgent to study and develop an alternative substrates too meet the needs of mass production.This study was aiming at investigating the effects of vermicompost-based substrates on seedling and cultivation of marigold. It included four parts.1, Effects of vermicompost complex media on marigold germination and root growth. Seven treatments and a control were prepared to study difference in seedling emergency. CK: 60%peat+ 20%perlite+20%vermiculite,T1:60%vermicompost+20% perlite+20%vermiculite,T2:0%vermicompost+50%vermiculite,T3: 75%vermicompost+ 25% vermiculite, T4: 50%vermicompost+ 50%perlite, T5: 75%vermicompost+ 25%perlite, T6: pure vermicompost, T7:substrate with all elements. Number of seedling emerged were recorded, based on which an emergence curve was made. Roots characteristics were measure at two-leaf stage. 2 Application of vermicompost composite matrix in marigold plug seedlings. Treatments including CK:60%peat+ 20%perlite+20%vermiculite, T1: 60% vermicompost+ 20%perlite+ 20%vermiculite, T2: 50%vermicompost+ 50%vermiculite, T3:75%vermicompost+25%vermiculite,T4:50%vermicompost+50%perlite,T5: 75% vermicompost+ 25%perlite. Stem diameter, height, fresh and dry weight of both above- and under-ground parts were determined and seedling index was calculated. Five seedlings of each treatment were chosen, transferred to pots, and grown in ordinary garden soil. Ten days later, leaf number, leaf length, branch number and chlorophyll content were measured.3 The effect of vermicompost composite matrix amended with nutrient solution on marigold plug seedlings. All treatments except T6A and T7 were added nutrient solution regularly. CK: 60%peat+20%perlite+20%vermiculite, T1A: 60%vermicompost +20%perlite+20%vermiculite, T1B: 60%vermicompost+ 20%perlite+ 20%vermiculite, T3A: 75%vermicompost+ 25%vermiculite, T3B: 75%vermicompost+ 25%vermiculite, T6A: pure vermicompost, T6B: pure vermicompost, T7: substrate with all elements. Plant height, stem diameter, leaf number, stem length, fresh weight and dry weight of over- and underground parts were measured and seedling index calculated. Some physiological characteristics including soluble sugar, chlorophyll and root activities were determined.4 The application of vermicompost in marigold cultivation. Control (CK) treatment contained substrate with all elements; the rest treatments had different ratios of garden soil to vermicompost : 100/0(treatment code is 100), 75/25(treatment code is75), 50/50 (treatment code is50), 25/75(treatment code is25), 0/100(treatment code is0). Each treatment was prepared with (code~)or without adding nutrient solution. Branch number, leaf number, plant height, stem diameter, chlorophyll and other physiological indicators were measured every other week. Starting from initial bloom stage, number and diameter of flowers, as well as plants crown were recorded regularly. SPSS statistical software was used to analyze the data. The results are as follows:1 In control germination of marigold seeds started earlier than in other treatments. In comparison, when treated with vermicompost-based substrates seeds germinated later, but grew faster after germination. There was no difference in germination rate. Roots of marigold seedlings in CK treatment were long with more branches, but smaller in diameter and not strong enough. Marigold seedlings of T6 and T7 treatments had strong taproot but few branches, which was not good for nutrient uptake and growth. In general, marigold seedling roots of T1-T5 treatments shared excellent growth index.2 At four-leaf stage, height, stem diameter, leaf number and leaf length of plants treated with vermicompost were significant higher than CK treatment. Seedlings grew in substrates with vermicompost were stronger and had large higher matter accumulation than control. T3 and T4 treatments were among the best and were better than the rest in all index. In the late cultivation stage, branch number of plants in T3 treatment were significantly higher than the rest.3. Adding nutrient solution increased plant height, leaf number, stem diameter and matter accumulation. Moreover, root activity was improved by adding nutrient solution. There was no significance in Chlorophyll content of each treatment. The soluble sugar content in plants of T6 was mch higher than that of other treatments.4. Higher vermicompost in cultivation substrates increased number of branches, leaves, crown area, and flower numbers, with 25% vermicompost is 25% as the optimum.It is feasible to replace peat with vermicompost as basic substrate for marigold's seedling, cultivation and large-scale production.