Genetic Variability and Interrelationships among Morphological and Agronomical Characteristics in Rhizome Lotus (Nelumbo nucifera Gaertn.ssp.nucifera) Germplasms Effect of different nitrogen forms and their ratio on agronomical character,economic and quality of flue-cured tobacco Comparison on the Main Agronomical and Quality Characters between Japonica Cultivars with Different Panicle Types in Jiang-Huai Area