Analysis of Genetic ×Environment Effect for the Main Econom ic Traits inBitter Gourd (Momordica charantia L. ) Genetic Variation and Individual Plant Selection of Main Economic Traits ofProgenies from the Second-generation Seed Orchards of Chinese Fir Effects of different mulching methods on physiological characteristics and economic traits in flue-cured tobacco Fiber Cell Morphology and Its Relationship with Economic Traits and Physical Properties of Ramie Wild Plant Correlation of main physiological characteristics and active componentsin cultivars of medicinal Chrysanthemum morifolium The Investigation and Comparison of Economic Traits of 95 Hazelnut Clones in Tieling