| Factors influencing tissue culture of green pepper were investigated and an efficient plant regeneration system was established. Transformation of green pepper was obtained by Agrobacteri urn-mediated transformation of leaf discs. Antisense PLD y gene was introduced into green pepper. I. Construction of green pepper regeneration system (1) Inducement of shootBased on the former's researches, we induced green pepper shoot differentiation through cotyledon as explant and MS as basic medium. In this experiment, the effect of 6-BA/IAA ratio, GA3, AgNO3, seedling age, light/dark treatment, medium pH, surgar concentration, cotyledon density and different organic style were studied. Results showed that higher 6-BA/IAA ratio was benefit for the shoot differentiation. When 6-BA/IAA ratio was higher than 10 or equal to 10 and 6-BA concentration (>3mg/L) was relatively high, the differentiation frequencies was biger than 50%. It was difficult for low concentration of 6-BA (<3mg/L) to restrain the root's differentiation, thus 6-BA concentration had more influence in pepper shoot regeneration. Adding certain IAA to the medium was beneficial for green pepper's shoot differentiation. On the medium of MS + 6-BA 5.5mg/L + IAA o.5mg/L, the differentiation frequencies of shoot reached the maximal numerical value-80%. We determined that this medium was suitable for shoot regeneration of green pepper. GA3 had complex effects on shoot differentiation. On the one hand, it could shorten the time of shoot's produce about 3-5days, and burl of shoot had visible elongation. On the other hand, GA3 decreased the shoot differentiation frequencies to about 60%, and the shoot grew badly. We thought it was unnecessary to add GA3 to the shoot regeneration. In this experiment, we found that AgNO3 shorten the time of shoot's produce about 1-2 days. At the beginning of differentiation, shoot grew fast. Low concentration of AgNO3 had little effects on the shoot induction, high concentration of AgNO3 was unfavourable for the shoot induction. In this experiment, it was unnecessary to add AgNO3 to medium. Experiment showed that shoot differentiation frequencies reached the maximum value-80% when seedling age was lower than 15 days and bigger than 11 days, sugar concentration was 30 mg/L and cotyledon densitywas 10 patch per utensil. Shoot differentiation had higher adaptability to pH. The change of pH on the definate scope had no disbennifit influence on shoot regeneration. It was appropriate for pH 5.8 to induce shoot differentiation. Dark treatment and high illumination intensity of around 2000 lux was unfavourable for shoot regeneration of green pepper, and low illumination intensity of around 1000 lux benifitted to it. Brownen phenomenon existed in tissue cultures. Antioxidant and sorbent could alleviated of brownen phenomenon to some extent, but could not solved this problem fundamentally. It was essential choosing breed with low content of hydroxybenzene for pepper regeneration. High shoot differentiation frequency and high shoot differentiation value could be achieved on MS organic, B5 orGAnic and ZH orGAnic.(2) Elongation of shootElongation of shoot was the biggest difficulty in tissue culture of green pepper. Shoot grew bloomingly on the medium of MS+ 6-BA 5mg/l + IAA 0.4 mg/1. Addition of GA34mg/L, shoot could elongate finely. In the end, we determined that (6-BA 5mg/l, IAA 0.4 mg/1, GA3 4mg/L) was the fittest hormone combination of shoot elongation. Zh organic came into being based on the MS organic. The fomer has folic acid, biotin, while the latter has not. On the phase of shoot elongation, shoot elongation frequency on ZH organic was higher than on MS organic, which means that ZH organic indeed accelerated shoot elongation. So we determined that MS salt+ 6-BA 5mg/l + ZH organic* IAA 0.4 mg/1 + GA34mg/L was the fittest medium on the phase of shoot elongation. In addition, culture circumstance had great effect on the shoot elongation. Culture circumstance included rigidity of medium and atmosphere humidity in culture vess...
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