Selection Of Substrate Compounds With Rice Husk As Raw Material Suitable To Tomato Cultivation

In this research, some biological and agricultural materials were chosen, such as fermented rice husk, mushroom scrap, corn cob and so forth, to be the substrates of tomato cultivation in plastic shed.The growth, yield, quality, nutrition absorption and distribution of tomato, changes of microbiology varieties and numbers in the substrates during different growth periods were studied and the physicochemical property of substrates, the pattern of nutrition absorption and distribution, the costs and benefits were analyzed, in order to provide tech support for tomato organic substrate culture. The five substrate compounds are as follows: A maize straw and wheat bran and regardless of slag with a ratio of 2:5:3; B rice husk and corncob and regardless of slag with a ratio of 5:2:3; C rice husk and maize straw and regardless of slag with a ratio of 5:2:3; D rice husk and corncob and regardless of slag with a ratio of 3:2:5; E corncob and wheat bran and regardless of slag with a ratio of 2:3:5. The main research results are as follows:(1) All physical and chemical features were all at the ideal range of tomato growth except porosity before cultivation. In the culture substrates, the content of quick effective P,K were far higher than CK. In the whole procedure of tomato cultivation, the PH and EC value in 5 different kinds of combined culture substrates all increased or decreased to some degree, but were generally under ideal range of tomato growth.(2) During the growth period after the last transplant, the height and stem width of tomato grown in compound B were no significant difference from CK, which of other compounds were all inferior to CK.(3) Different culture substrates had a great effect on tomato yield and fruit quality, among which, merely treatment B and C approached to CK. Compared with CK, organic cultivation could greatly improve the fruit quality, and treatment B was the most significant one.(4) During the whole growth period, the uptake of nutrients of tomato in the treatment B was largest. At the end of experiment, the content of K was noted higher than N and P in the different organs of plant, especially in the fruit. The contents of N,P,K in different organs in treatment B were all higher as compared to others.(5) The results showed that the quantity of bacteria ranked the first in different substrates, the quantity of actinomycete was the second, and fungus ranked the last. The quantity of bacteria and fungus of treatment A, B and C reached a peak in the early stage of fruiting, but that of bacteria and fungus of treatment D,E and CK reached a peak in the middle stage of fruiting. There were the largest number of bacteria in treatment C and that of fungus in treatment A. The quantity of actinomycete of 6 substrates all reached a peak in middle stage of fruiting, all of which, the number of actinomycete in treatment B was the largest. During the growth period of tomato, the number of bacteria and actinomycete were both larger than that of CK.(6) Among 5 culture substrates, the most economic benefit substrate was treatment B, which was 1.56 % more than CK. In addition, the culture substrates of all treatments were all agricultural and biological materials, so their economic benefits were much higher than CK.In summary, treatment B was the best substrate, which could be used to replace grass peat as organic culture substrate.