关键词: 北京地区, 北京地区, 野生景天, 繁育, 适应性

Abstract: According to the data obtained through quadratic rotated combination design on the basis of “five factors”-sowing date (x1), density (x2), nitrogen fertilizer (x3), keeps the bearing-branch number (x4), bearing-branch number of combs out bud (x5) et al, and “five levels”. By the agronomy measure, colony developments, cotton boll opening situation and the output constitution, the regression model of two objective properties was established, such as ginned cotton output and cotton ripe before frost. The result indicated the comprehensive agronomic is reasonable. Then, high yield and high quality colony developments on the crops were studied. And the management index of cottons’ growing, and change relations between the output factors from the situation of mature bolls’ distribution and the influences were found. Then, different output levels of output composition were simulated. The main directions of attack on gaining yield output have been defined. The optimum cultivation measurements of shorter growing period cotton for high output high economic benefit were that: sowed in may 22-23, density is 7300-7500, N 11.04-12.0 kg, keeps the bearing-branch to count 8.4-8.7, combs the flower bud of lower part bearing-branch.