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近十多年来,国外核桃生产发展很快,总产超过了扁桃,居世界干果第一位。其主要特点是:选用良种,适地栽培,单产较高。以法国为例,1960年以后,大规模地建立了一批新的核桃种植园,栽植10—15年的一般亩产核桃330斤,管理好的亩产可达533斤。我国自张骞出使西域引回核桃,至今已有2,000多年的栽培历史。核桃栽培已从西部地区扩展到黄河流域和东北地区,形成为传统的出口商品。建国以后,我国也重视了核桃生产的发展,并加强了这方面的研究。按栽培株数计算,已居世界第一位。但单产和总产偏低,年产仅10万
In the recent ten years, the overseas walnut production has developed rapidly and the total output has surpassed Almond, ranking the first in the world for dried fruits. Its main features are: selection of elite, suitable for cultivation, higher yield. Take France as an example. After 1960, a number of new walnut plantations were established on a large scale. 330 kilos of walnuts were planted for 10-15 years and 533 kilos were managed well. Since China invited Zhang Qian to reclaim the walnut in the western region, it has more than 2,000 years of cultivation history. Walnut cultivation has expanded from the western region to the Yellow River and the northeast region, forming a traditional export commodities. After the founding of our country, our country also attaches importance to the development of walnut production, and strengthened the research in this area. Calculated by the number of cultivated plants, ranking first in the world. However, yield and total production is low, with an annual output of only 100,000