Studies On Characteristic And The Establishment Of Tissue Culture Regeneration System Of An Early Strain Of Lotus

An early maturing lines of Lotus (Lotus corniculatus L.) is a new strain selected from Mirabal (Lotus corniculatus L.cv. Mirabal).To study the developmental growth characteristic and productive performance of early maturing lines of Lotus and tissue culture regeneration system can provide evidence for production application of early maturing lines of Lotus and application of transgenic and other biotechnology of Lotus. The result showed:1 The natural height of early maturing lines of Lotus is significantly lower than the natural height of Lotus'original population, the difference between natural height and absolute height of early maturing lines of Lotus is 18.78cm, but the difference between natural height and absolute height of Lotus'original population is 5.29cm, this shows that the creeping of early maturing lines of Lotus is better than the creeping of Lotus'original population. In close-planting cultivation, during the whole growth period the branch number of early maturing lines of Lotus don't change significantly, but the length branch change greatly in the whole growth period, it is very important to the grass yield. With the branch stretching and turf height increasing, natural height can restrict the growth and development of lateral branch, and can decrease the grass yield per plant. The average pod number (211.35) per plant of early maturing lines of Lotus is significantly more than the average pod number (155.29) per plant of Lotus'original population. The average seed number per pod of early maturing lines of Lotus is more than the average seed number per pod of Lotus'original population. From above indicated that the seed yield of early maturing lines of Lotus is higher than other lines.2 The correlation and path analysis of 11 agronomic characteristics were studied with per plant of Lotus and the correlation and path analysis of 7 agronomic characteristics were studied with per plant seed yield in Lotus. The results showed that the correlation between yield(Y) of per plant and branch length(X2),branch nodes(X3),branch stem diameter(X4),the number of sub-branches(X5),sub-branch length(X7),sub-branch nodes(X8),sub-branch stem diameter(X9) is extremely significant, and the correlation between yield of per plant and branch number(X1), natural height(X11) is significant,while other two characteristics including length of branch leaf stalk(X5), length of sub-branch leaf stalk(X10) were not correlated significantly to the yield. The correlation between seed yield(Y) per plant and seed setting rate(X5), pod length(X6), seed number per pod(X7) is extremely significant, and the correlation between seed yield per plant and branch number(X1), inflorescence number of pod setting per branch(X4) is significant, while other two characteristics including inflorescence number per branch(X2), floret number per inflorescence(X3) were not correlated significantly to the yield. The result of path analysis showed that the influence of 11 characteristics on yield is: branch length(1.1216) > branch nodes (0.3463) > sub-branch length (0.1146) >branch number (0.1064) > branch stem diameters (0.0846) > sub-branch nodes (0.0342)> sub-branch stem diameters (0.0289) > sub-branch number (0.0216) > length of sub-branch leaf stalk (-0.0436) > length of branch leaf stalk (-0.0654) > natural height (-0.7482).The influence of 7 characteristics on seed yield is: seed number per pod (0.4335)> inflorescence number of pod setting per branch (0.2411)>seed setting rate (0.2193)> floret number per inflorescence (0.2125)> pod length (0.1369)>branch number (0.1300)> inflorescence number per branch (-0.2617).It is difficult to harvest the Lotus seed because of the growth period of Lotus between the different plants have significant difference, and the initial flowering and the final flowering of a plant is different, it leads to the time of seed maturation is inconsistent. Lotus is very easy to loose pod mouth. With the seed becoming mature, more and more seeds loose pod mouth, it leads to more and more seed losing. With the harvest time delaying, the harvested mature pod number is increase, but after it increases to some extent, it begins to decrease. In this test, the maximum peak number of harvest pod is 64.9% in July 12th. The seed number of loose pod mouth and the mature seed number can restrict the quality and quantity of the harvested seed of Lotus. During the yellow ripe stage, the harvested seeds have advantages of large-grain, heavier 1000-grain weight and high yield. The maximum yield of harvested seed is 536.5kg/hm2 in July 12th. The seed yield and 1000-grain weight increased gradually with the time before July 12th.The optimum harvest date is at July 12th, because the mature seed loose pod mouth, it leads the seed yield and 1000-grain weight decreased gradually with the time after July 12th. Although the germination characteristics of Lotus seed of green ripe stage is worse than the germination characteristics of Lotus seed of other mature period, it has rather high seed practical value. The Lotus seed is easily to loose pod mouth, so we can harvest earlier.3 The regeneration is an important characteristics of perennial grass, the most perennial grass can regenerate after mowing and grazing. The regeneration of early maturing lines of Lotus is a performance of viability, and it can measure economic performance. In this test, the early maturing lines of Lotus is test material, plant height, regeneration rate, branch number of regeneration, regeneration intensity and plant weight as observation index, and mainly analyze the plant regeneration. The main results are the following: The characteristics of plant first-cut shows great variability. The coefficients of variation for branch number and plant weight is 32.07%,22.16% respectively; the coefficients of variation for plant height and regeneration intensity is 5.74%, 18.84% respectively;The coefficients of variation for regeneration total weight, regeneration branch number and regeneration intensity is 34.71%,32.55%,24.38% respectively; the coefficients of variation for regeneration plant height and regeneration rate is 12.98%, 18.75%. For the annual grass yield, the first-cut and the second-cut occupies the major proportion. The first-cut is 58%, the second-cut is 25%, the third-cut is 17%.