The Study Of Factors That Corn Stalk Fermentation Substrate Inhibit Seeds Germinate And Ways To Improve It

With the corn stalk fermentation matrix as the main research object, this study aims to find the reason that why seeds are hard to germinate in the corn stalk fermination substrate, and find a suitable way to improve it, and finally make it perform well in seedling and become a new kind of nursery substrate replacing peat. The reason that corn stalk fermentation substrate inhibite seeds germinate well can be devided into four parts: the p H value is high, and EC value is high, too much organic matter(like aldehyde and phenol, etc.) and poor hydrophilicity. Up to now, there’s large quantities of reports about how to decrease the p H value and EC value, but the researches on reducing the content of organic matter or improving the hydrophilicity are few. This research mainly modified the corn stalk fermentation substrate by reducing the content of total phenol and improving its hydrophilicity. Then, a calendula and petunias seedling experiment was carried out to measure their germinatation rate, germinatation energy, plant height, number of leaves and length of roots. The main results were as follows:(1) The test result of aldehyde material’s content included in the corn stalk fermentation substrate are very few, lower than detection range, so we can see that they’re not inhibiting factors of seed germination. The content of vanillin and coumaric acid in corn stalk fermentation substrate are lower than those in peat, and it hasn’t ever appeared that peat substrate inhibitits seeds germinate in pratical application, so it can be concluded thar vanillin and coumaric acid are not the factors of inhibiting seeds germinate, or its content is too small, and it’s not enough to affect the seed germination, We detected 0.46 ug litac aldehtde in 1 g corn stalk fermination substrate, and think its content is not enough to inhibit seed germination.(2) The physical and chemical properties determination results of corn stalk fermentation substrate treated with potassium ferrate show that the p H value get lower than that which aren’t treated by potassium ferrate. The substrate changes from the original partical alkaline environment into neutral to acid environment, becoming beneficial to plant growth.. Its EC value increases. The higher EC value makes it more conducive to the growth of plants. Treated with potassium ferrate hans little effect on the bulk density and porosity of substrate. The bulk density and porosity of substrate are invariably in appropriate range that plant requires.(3) The determination results of total phenol content show that with the increase of dosage of potassium ferrate, the content of total phenol in corn stalk fermentation substrate is on the decline. Potassium ferrate can effectively reduce the content of total phenol in the corn stalk fermentation substrates. When 1 kg corn stalk fermentation substrates mixed in 2 g potassium ferrate, the content of total phenol in corn stalk fermentation substrate could be reduced to 0.16%.(4) After processing the corn stalk fermentation substrate with potassium ferrate, the calendula and petunias seedling test results show that their germination rate, germination energy, plant height, number of leaves, and length of roots are improved significantly. With the increase of dosage of potassium ferrate, it appeared an upward trend in the germination rate and germination energy. Potassium ferrate improve the quanlity of corn stalk fermentation substrate mainly throngh reducing its content of total phenol and decreasing its p H value. As the fact that potassium ferrate can increase the EC value, it’s not good to mix with too much potassium ferrate into corn stalk fermentation substrate.(5) The physical and chemical properties determination results of corn stalk fermentation substrate treated with polyglutamic acid show that water-holding porosity of corn stalk fermentation substrate increased after processed with polyglutamic acid. Its capability of holding water is markedly enhanced. The p H value decreases a little. There’s not too big change in density and EC value.(6) After processing the corn stalk fermentation substrate with polyglutamic acid, the calendula and petunias seedling test results show that the calendula and petunia seeds germination rate increases first with the increase of dosage of polyglutamic acid, but present downward trend when go on increasing polyglutamic acid. When mixing 0.25 m L polyglutamic acid into 1 kg corn stalk fermentation substrate, the seed germination rate gets highest, significantly higher than the seed germination rate of treatment 1(corn stalk fermentation substrate without the polyglutamic acid processing), even higher than the seed germination rate in peat substrate. The statistic results of calendula and petunia seeds germination energy in the 10 th day after sowing show that treatment 2 is also significantly superior to other groups. Calendula and petunia’s plant height, number of leaves and length of roots in second treatment are nearly same with those in the control group, and are superior to other treratments. Analysising various of indexes, it is concluded that corn stalk fermentation substrate are significantly improved by treated with polyglutamic acid, and show an better performance in seedling than peat.