Why can't old shoots be used for grafting eggplant? Cause analysis
After eggplant flowers and sets fruit heavily, the root system's absorption function gradually declines. At this time, management should be strengthened to delay plant senescence, promote continued flowering and fruiting, and extend the harvest period. Fertilize in time, applying fertilizer once every 15-20 days, each time 10 kg of nitrogen-phosphorus-potassium compound fertilizer per mu, plus 15 kg of fully soaked and decomposed soybeans...
Using Turubamu (Solanum torvum) as rootstock to graft eggplant is indeed a good way to control eggplant root-knot nematode. It not only has good effect, low cost, and is simple and easy to carry out, but can also effectively control "dead plants" caused by eggplant Verticillium wilt, Fusarium wilt, root rot, and the like. But recently some vegetable growers and seedling suppliers, in order to save money on seeds, use old shoots from eggplant plants in the late growth stage as scions to graft eggplant, seeking huge profits from it, which has caused some problems in production. First, the survival rate of grafted seedlings is relatively low. If eggplant seedlings are used as scions for grafting, as long as the technique is up to standard and the measures are appropriate, the survival rate of grafted seedlings is generally above 90%, while grafting with old eggplant shoots under the same operation gives a survival rate of only 60%. Second, eggplant grafted with old shoots has low yield and poor market quality. According to the author's incomplete survey, in the same greenhouse under the same fertilizer and water management, compared with grafting with seedlings, grafting with old shoots reduced yield by 1500-2000 kg per mu, and reduced income by 4000-5000 yuan per mu.Analyzing the reasons, the author believes: First, old eggplant shoots have a high degree of lignification and poor vigor. After grafting with Turubamu, early compatibility is poor, various vascular tissues are not unobstructed, and the transport of nutrients and water is blocked. Second, the sprouting of old eggplant shoots all carries flower buds. The healing of grafted seedlings and flower bud differentiation proceed simultaneously, and competition for nutrients will lead to poor flower bud differentiation, thus causing low yield and poor market quality of eggplant. Third, old eggplant shoots often carry many pathogens. It is only because of environmental conditions that disease does not occur. After grafting with them, once the greenhouse environment is poor, various diseases will soon occur, which will undoubtedly increase the cost of disease control.