衡阳市紫色土区金槐嫁接育苗及高效栽培技术研究

Study on Grafting and Seedling-Raising and High-Efficiency Cultivation Techniques of Sophora japonica cv. Jinhuai in the Purple Soil Area of Hengyang City

摘要: 为破解衡阳紫色土区金槐嫁接成活率低、栽培产量不稳定及土壤贫瘠等产业瓶颈，以金槐优良品种(桂G9-1、桂G9-2)为研究对象，在衡阳县西渡镇陡岭村试验基地开展系列田间试验，系统探究嫁接育苗关键技术及紫色土栽培优化措施。通过设置基质类型、砧木密度、嫁接时间与接穗年龄等育苗试验，以及种植密度、追肥模式、冬季修剪时间等栽培试验，分析各处理对金槐嫁接成活率、植株生长量及槐米鲜质量的影响。结果表明：① 沙质壤土(黄心土:河沙 = 1:1)是国槐砧木育苗的最优基质，砧木适宜保留密度为株行距10 cm × 25 cm (40株/m²)；② 金槐枝接以3月采用1年生接穗成活率最高(96.7%)，芽接最佳时间为春季3月与秋季10月(成活率均达97%以上)；③ 紫色土栽培中，土层厚度 < 30 cm、30~50 cm、>50 cm时，适宜种植密度分别为2.5 m × 3 m、3 m × 3.5 m、3.5 m × 3.5 m；④ 最优追肥方案为尿素0.2 kg/株 + 复合肥(N:P:K = 15:15:15) 0.3 kg/株，成年树冬季修剪最佳时间为2月。研究明确了衡阳紫色土区金槐嫁接育苗与高效栽培的关键技术参数，为当地金槐产业提质增效及生态经济型林业发展提供科学依据与技术支撑。

Abstract: To address the industrial bottlenecks in the purple soil area of Hengyang, such as low grafting survival rate of Sophora japonica cv. Jinhuai, unstable cultivation yield, and poor soil fertility, a series of field experiments were conducted at the experimental base in Douling Village, Xidu Town, Hengyang County, with elite S. japonica varieties (Gui G9-1 and Gui G9-2) as the research objects. The study systematically explored the key technologies for grafting and seedling-raising, as well as the optimized cultivation measures for S. japonica in purple soil. Seedling-raising experiments (including different substrate types, rootstock densities, grafting times, and scion ages) and cultivation experiments (including different planting densities, topdressing modes, and winter pruning times) were designed to analyze the effects of various treatments on the grafting survival rate of S. japonica, plant growth, and fresh weight of Huaimi (flower buds of S. japonica). The results showed that: 1) Sandy loam (yellow subsoil:river sand = 1:1) was the optimal substrate for raising rootstocks of S. japonica (rootstock for Jinhuai), and the suitable rootstock retention density was 40 plants/m² with a plant-row spacing of 10 cm × 25 cm; 2) For branch grafting of S. japonica, the highest survival rate (96.7%) was achieved when using 1-year-old scions in March, while the optimal times for bud grafting were March (spring) and October (autumn), with survival rates both exceeding 97%; 3) In purple soil cultivation, the suitable planting densities were 2.5 m × 3 m, 3 m × 3.5 m, and 3.5 m × 3.5 m when the soil layer thickness was <30 cm, 30~50 cm, and >50 cm, respectively; 4) The optimal topdressing scheme was 0.2 kg urea per plant + 0.3 kg compound fertilizer (N:P:K = 15:15:15) per plant, and the best time for winter pruning of mature S. japonica trees was February. This study clarified the key technical parameters for S. japonica grafting, seedling-raising, and high-efficiency cultivation in the purple soil area of Hengyang, providing a scientific basis and technical support for improving the quality and efficiency of the local S. japonica industry and the development of eco-economic forestry.