The Research Of Different Moisture Content On The Growth Status, Iron And Resistance Characteristics Of Caragana

This paper studied the effects of different moisture content on the growth status, iron content, chlorophyll content, MDA content, SOD activity, POD activity, CAT activity and crude fiber content of Caragana microphylla through pot experiment. The results showed that:(1) The plant height, root length, shoot dry weight, and root dry weight of Caragana microphylla increased first, and then decreased with the reduction of moisture content.The results showed that Caragana microphylla grows best under 30%-40% moisture content, and worst under the 60%-70% moisture content.(2) The order of iron content of Caragana microphylla was root>leaf>stem, and the content reached the highest on the 138d. The effect on root iron content was irregular under. Stem iron content was the largest under 40%-50% moisture content (88d) and 50%-60% moisture content (113d.138d, 163d?188d). Leaf iron content was the largest under 60%-70% moisture content.(3) The moisture content of Caragana microphylla's leaf and root decreases with the moisture content reduction, but were above 60% and 50% respectively.(4) The chlorophyll content of Caragana microphylla's leaf appears two peaks on the 113d and 163d respectively. With the decreasing of moisture content, chlorophyll content is the highest under 30%-40% moisture content (The chlorophyll content reaches highest under 40%-50% moisture content on the 188d). The chlorophyll content was lowest under 60%-70% moisture content on the 88d, and the chlorophyll content was the lowest under 50%-60% moisture content at the rest of time.(5) With the extension of Caragana microphylla's growth period, the MDA content of Caragana microphylla leaf appears two peaks on the 138d and 188d, and the MDA content were the highest under 20%-30% moisture content every time; SOD activity also appears two peaks on the 113d and 163d respectively; POD and CAT activity increased first and then decreased, and reached the largest on the 138d and 163d respectively. The activity of SOD, POD and CAT of 40%-50%,30%-40%,20%-30% moisture content increased at different degrees than 60%-70%,50%-60% moisture content.(6) With the extension of Caragana microphylla's growth period, the crude fiber content of Caragana microphylla's root and stem increased first and decreased afterwards and reached the largest on the 138d. With the decreasing of moisture content, root crude fiber content were the largest on the 88d, 113d and 138d under 50%-60% moisture content, and on the 163d and 188d under 40%-50% moisture content; while stem crude fiber content were the largest on the 88d and 113d under 20%-30% moisture content and on the 138d,163d and 188d under 40%-50% moisture content.