| The proportion of waterlogging in the natural disaster has increased in recent years, which was found to be dominant in the plain area of the middle and lower Yangtze River Basin.Peach is one kind of waterlogging untolerance deciduous trees,which belongs to Rosaceae. It is sensitive to waterlogging, which can cause fallen leaves, fruit drop and even death. Maotao, which is mainly choosed as the peach rootstocks in South China region, but it got bad waterlogging tolerance. Therefore, waterlogging has become the main restrict factors of the peach industrial development in the Southern rainy area. In this study,’Maotao’(Amygdalus persica L.),’Dongxixiaoxiantao’ and ’Zhenxuan1’was used as materials, effects of tolerance and physiological response of three peach rootstocks were studied under waterlogging, the main factors contain morphological characteristics, waterlogging Index, malonyldialdehyde, superoxide dismutase and peroxidase.and then the tolerance and physiological response of three peach rootstocks could be analyzed. Moreover, on this basis, tissue culture of shoot-tips was carried out by using stems of ’Zhenxuan1’,’Dongxixiaoxiantao’and’Maotao’ as the external plants. Effects of different sterilization methods, base midum, kinds and concentration of phytohormone on the primary culture,multiplication culture and rooting culture were studied. The main results were as follows:1. Through the survery of the three seedling peach rootstocks, we found that the plant of’Zhenxuan1’ suffered the lighter injury than others, which was the most tolerant to waterlogging,’Maotao’ was sensitive and ’Dongxixiaoxiantao’was moderate one. It was found that a tiny amount of leaves of ’Maotao’ wilted on the3rd day. On the day of5th,the leaves began to crisp and the fraction of lower leaves turned to shed, on the7day, the leaves got withered; some of lower leaves of ’Dongxixiaoxiantao’ began to wilt on the5th day, it got crisped on the7th day; but the leaves of ’Zhenxuan1’began to wilt slightly on the7th day.The difference of physiological indices of three peach rootstocks under flooding stress, would be relevant to rootstock’s waterlogging tolerance. It showed that the root activity, chlorophyll content and chlorophyll fluorescence parameters of three peach rootstocks all decreased,’Zhenxuan1’got the minimum decrease compared with ’Dongxixiaoxiantao’ and ’Maotao’; The leaves cell membrane permeability and the change of MDA purity have increased trends. Among those,’Zhenxuan1’increased the most minimum amplitude compared with ’Dongxixiaoxiantao and ’Maotao’; A tendence of the activity change of SOD and POD, which increased firstly and then decreased under waterlogging.The SOD and POD activity of ’Zhenxuan1’maintain a higher level.2. The shoot-tips culture system was established initially through the screening of different impact factors of the first, proliferative culture and rooting culture. The75%alcohol30s and the0.1%HgCl23min was the best sterilization treatment for primary culture, the higher survival rate was found when explants of three materials were sampled from the bottom part of plant, the MS+6-BA0.5mg/L+IBA0.2mg/L was the best first culture for ’Dongxixiaoxiantao’and ’Zhenxuan1’; The MS+6-BA1.5mg/L+IBA0.2mg/L was suitable for the multiplication culture of ’Maotao’ and ’Zhenxuan1’, The MS+6-BA1.5mg/L+IBA0.5mg/L was the best for’Dongxixiaoxiantao’ multiplication; The1/2MS was the most suitable medium for rooting culture, The1/2MS+IBA1.0mg/L was fit for ’Maotao’ and ’Zhenxuan1’,1/2MS+IBA0.5mg/L was the most suitable for’Dongxixiaoxiantao’. |
