Tissue Culture Studies On Tetraploids Of Robinia Pseudoacacia

Compared with the common balck locust tree, The Tetraploids of Robinia pseudoacacia has many desirable traits,such as faster growing bigger leaves. wider and denser branch,it is regard as the key species for afforesting in deseart mountain,in certain degree ,tetraploid locusts are tolerant of a wide rang of soil types ,such as salty and alkaline soil , barren soil and so on.it owns the capacity of tolerant to drought, dusty and somky condition , they can withstand windy and sandy weather,at the same time, having a lump, its root can fix the nitrogen in the atmosphere, increase the organism in the soil and grain construction, improve soil quality, conserve water and soil, defend wind preserve the sand .It is the first preference for greening the surroundings of farms and rural communities The leaves of animal feed type of the Tetraploids of Robinia pseudoacacia imply a higher nourishment composition and they are the superior quality's woody animal feed. According to report, the Tetraploids has been successfully introduced into west China, the numbers of tetraploids introdued from foreign country were limited, They are propogated by grafting and cutting, but the propogating speed and coefficient is low, hence tetraploids plantplet supplys fall short of demand and inpede them from gengralizing. Realizing its fast and large scale of production is important to gain high propogating coefficient, supply high quality nusery stocks in bratches, speed breeding this good strains and meet the needs of forestry production. Few articles on the tetraploids have been reported. Purpose of this study is to setup fast propagating system of the tetraploids, Studys on tissue culture of two clones of tetraploids which offered by propagating center in shannxi province had been syetematically and thoroughly proceeded. The two clones which originate from Forestry beeding institute of Korea were introduced into China in 1997 from. Results of tissue culture of the two clones were as fllows.We proceeded the study of tissue culture on the Tetraploids of Robinia pseudoacacia .It is the first key technique of tissue culture to choose explant and to disinfect, the enunciation on the experiment study that the stem segment is the best explant for sterile shoot cutting,the young leave and the formation layer under skin department is best explant for organogensis; the best disinfection method of explant is: the stem segment is gradually soaked into 70% alcohol about 30s, then explant were surface sterilized by soaking in 0.1% HgCLj for about 10 mins, followed by repeared washing five times with sterilized water to remove the traces of sterilant.For induction of morphogenesis,prolifera-tion,MS(Murashige and Skoog,1962)having3% sucrose(as a carbonhydrate source)was used as basal medium.In the establishment of cultures, the results showed that stem segment with axillary bud growed wel 1 on MS mudium with l.Omg/L BA and O.lmg/L. In the multiplication and elongation of cultures, the results showed that K3 clone clumps of buds after giving them a duration treament of 0.5mg/LBA +0.1mg/L NAA+0.5mg/L, showed better elongation, but K4 clone showed better elongation with treament of l.Omg/L KT+ 0.5mg/LNAA+ 0.5mg/L BA, the cultures established on 0.5mg/LBA+0.5mg/LKT+0.1mg/LNAA gavemaximum multiplication of shoots for K3 clone, for K4 clone maximum number of buds was observed by regular subculture in 0.5 mg/L BA+1.0 mg/L KT+0.5 mg/L NAA.Calli were induced from immature leaves and the formation layer under skin department. Cultures on MS medium in combination with 0.3 mg/LBA and 0.5 mg/L2.4-D is optimal for the induction of K3 clone, but for K4 clones the concentration of 2.4-D is one times higher. The calli from immature leaves of K4 clones showed maximum differentiating rate on the cultures with 0.6 mg/LKT in accordance with 1.0 mg/LBA and O.lmg/LNAA, as compared with the calli from phloem, cultures on 0.6mg/LKT+1.0 mg/LBA+0.5 mg/LNAA showed maximum differentiating rate. But the optimal plant growth regulator in differentiating for leaf-derived...