Establishion Of Mature Embryos Regeneration System And Determination Of Relevant Physiological Indicators In Barley

Barley （Hordeum vulgare L） is the fourth largest crop in China, which is used as themain raw material for beer industry, and it plays an important role in the development ofnational economy. Establishing a regeneration system of barley is based on the theory thatliving plant cell have all omnipotent quality and it can redifferentiate a new plant through thephase of callus. It provides a foundation for many other researches, especially the transgenetechnique, which depends on a highly stable regeneration system. In order to optimize aregeneration system of tissue culture from mature embryos in barley and select ideal genotypesfor transgenic research，five barley varieties （Ganpi3, Ganpi4, Ganpi6, Marine and Belana）were selected to determine the influence of genotypes, media and seed cuttings on the embryoderived callus induction and plant regeneration. The changes of physiological indexes and theendogenous phytohormones content was studied in the process of barley regeneration.Compared the difference of physiological indexes between regenerated seedlings andcultivation seedling during the same period.The main results are as follows:1. A total of55SSR markers were used to analyze the genetic difference among these5varieties, showing some differences among them. Cluster analysis demonstrated that ganpi3,ganpi4, ganpi6were grouped together; marine and Belana were grouped together. The callusinduction rate, regeneration rate of mature embryo were significant different in5barleyvarieties. Callus induction rate of Belana is higher than others. Among the five barley cultivarsGanpi3, Ganpi4, Belana were identified with good performance in callus induction and plantregeneration. Media A₃、B and C2were suitable to the plant regeneration. The callusinduction rate of seed scraping broken and seed cutting longitudinally was higher than that ofcutting laterally.2. With the growth of callus, there was a same trend in the activities of SOD, POD, CAT.The SOD, POD, CAT activities was at a low level in the first7days, and then graduallyincreased with the growth of callus, and after a period of time, gradually reduced untildifferentiated seedlings. MDA content was at a lower level （≤9.114umol/g） in the callusgrowth process. There was significant difference on the content of all kinds of physiologicalindexes among variety of regeneration seedlings.the regular pattern of physiological indexesbetween regeneration seedlings and cultivation seedlings at the same period were similar.3. When the barley mature embryo callus in7¹4ds, GA₃and IAA content sharplyrose to a peak, but ABA and ABA/IAA ratio was relatively low. When callus after successive transfer into the redifferentiation period, the content of ABA had increased, but the content ofIAA and GA₃had a downward trend. At the same time, ABA/IAA ratio was increases. TheABA/IAA ratio reached to the highest adventitious is the best time to bud differentiation.