Abstract:

In order to study the feasibility of utilizations of fermented Helianthus tuberosus straw（FHTS）as substrates，and to find a proper proportions of mixed substrate for soilless cultivation，the growing adaptability of tomato in mixed substrates with FHTS was researched. In the control group（CK），peat︰vermiculite = 2︰1；five treatments were set with the proportions of FHTS being 10%，20%，30%，40% and 50%. Physicochemical properties of the compound substrates were tested and effects for growth，quality，yield and disease resistance were carried out. The results showed that a higher proportion of FHTS resulted in lower bulk density（BD），total porosity（TP），and water retaining porosity（WTP）. However，water-holding capacity（WHC），aeration porosity（AP），void ratio（VR） were raised with the increasing proportion of FHTS. Plant height of 30% treatment was increased 8.22% than that of CK. Pn were first increased and then decreased with the increasing proportion of FHTS，and treatments of 10%，20%，30%，and 40% were 21.53%，17.72%，14.77% and 14.20% higher than that of CK，significantly. Disease index（DI）of CK（70.00）was higher than that of other treatments（35.72–51.98）. The content of soluble solids，vitamin C，soluble sugar，sugar acid ratio were first increased and then decreased with the increasing proportion of FHTS. And the amount of FHTS added was 20%–30%，the content of vitamin C，soluble sugar and sugar acid ratio were significantly higher than that of CK. Titratable acid of CK was higher than that of other treatments，and sugar acid ratio of 30% treatment was the highest and 110.39% higher than that of CK，significantly. Yield per plant of 20% and 10% treatments were 14.50% and 12.50% higher than that of CK. The observed consequences indicated that 20%–30% volume proportions of FHTS were suitable for tomato cultivation.

Key words: Helianthus tuberosus, straw, mixed substrates, tomato, culture substrate