Research On Autotoxicity Of Lanzhou Lily Root Exudates And GC-MS Analysis Of Allelochemical

Lanzhou lily is placed in family Liliaceae and is a variety which comes from Lilium David, As only sweet lily in China, Its scales white plump, sugar content high and has very high value in edibleness and medicine which is welcome by consumers. With the increase of market demand, the cultivation area of Lanzhou lily is expanding year by year, The problem of continuous cropping obstacle caused by Root Self toxicity is also becoming more and more serious in production. In this experiment, two level bulbs of Lanzhou lily as root exudates collect material, and the three level bulbs of the Lanzhou lily as the self toxin receptor material, through timing and quantitative irrigation of different proportion of root exudates to study the effects of root exudates on the growth and physiological changes of Lanzhou lily seedlings. And using GC-MS analyzed the main component of Lanzhou Lily hydroponic 30 days of root exudates, through seed germination experiment discussed allelopathic activity of five potential allelochemicals. The main results were as follows:(1) The thirty days Lanzhou lily root exudates were collected with the method of hydroponic cultivation, Through feeding block experiment to study the proportion of different concentrations of lanzhou lily root secretion of lily seedlings, root morphology, seedling leaf chlorophyll content, antioxidant enzyme activity and osmotic adjustment substance content in lily seedlings leaves were investigated. The results showed that with the increase of concentration of root secretion, lily seedlings growth decreases, 25%, 50% of root secretion has different degrees of promoting effect on seedling growth, 75%, 100% of root secretion of seedling growth showed different degrees of inhibition and 100% of root secretion inhibition is the largest. Root secretion lily in seedling leaves superoxide dismutase, peroxidase(POD), catalase(CAT)activities increased,Root activity,chlorophyll, malondialdehyde(MDA) and proline(Pro) content decreased.(2) Five different organic solvents, petroleum ether, ether, aceticether, trichloromethane and methyl alcohol, were used to separate the lily root exudates, and using Gas Chromatograph-Mass Spectrometer-computer(GC-MS) technology for component identification. The results showed that 24 different types of compounds, including phenols, ketones, aldehydes, esters and alcohols, were detected in five groups. The petroleum ether group points detected in 6 kinds of substances, mainly for phenolic esters, such as 2,4-DTBP and DBP, relative contents were 15.38% and 37.02%, respectively; The ether part detected 10 substances, mainly for 2,2’-methylenebis(6-tert-butyl-4- methyl-phenol), BPA, 2,6-Di-tert-butyl-4-methlpyhenol, relative contents were 34.56%, 28.42%, 24.09%, respectively; The 7 kinds of substances were detected in the aceticether group, mainly for 2,2’-methylenebis(6-tert-butyl-4-methyl-phenol), BPA, and relative contents were 37.65%, 37.22%, respectively; Trichloromethane group detected in 7 kinds of substances, mainly 2,4-DTBP, palmitic acid, 2,2’-methylenebis(6-tert-butyl-4-methyl-phenol), and relative contents were 30.70%, 15.27%,13.58%, respectively; Methyl alcohol group detected only four kinds of substances, mainly for BPA and Bis(2,4,6-trimethylphenyl) ketone.(3) Through different concentration( 0.1mmol/L、1mmol/L、10mmol/L) of 2,4-DTBP, DBP, BPA, 2,2’-methylenebis(6-tert-butyl-4-methyl-phenol) and Palmitic acid treatment radish seeds, this paper studied the effect of this five potential allelochemical on the seed germination, seedling growth, antioxidant enzyme activity, So as to explore their allelopathy strength. The results showed that with the increase of this five substances concentration, the germination rate, germination index, hypocotyl length, radicle length and fresh weight of radish were inhibited. The 10 mmol/L of DBP has strongest inhibitory action, and compared to the control the inhibitory action on the germination rate, germination index, hypocotyl length, radicle length, fresh weight were 30% and 32.8%, 31.5%, 23%, 21.4%. At the same time, in the concentration range of 0.1-10mmol/L, SOD activity increased first and then decreased, the activity of POD increased, and the content of MDA increased.