苹果树改劣换优时要防止产生高接病自１９８３年以来，我县山区苹果生产发展很快，但因缺乏周密规则，盲目地发展了一些劣质品种，而适销对路的优质品种却极少，因此很多果农改接为以红富士为主的优良品种，从而取得了一定成效，然而发现改接后的果树出现很多病症，造成一... Since 1983, the production of apples in mountainous areas of our county has developed rapidly. However, due to the lack of thorough rules, some poor-quality varieties have been blindly developed while the high-quality varieties that are marketable are extremely poor Therefore, a lot of fruit growers changed to good varieties mainly based on red Fuji, which achieved certain results. However, many diseases of fruit trees after the change were discovered, resulting in a ...