Morphological Studies on Seeds from 5 Species of Medicinal Rhododendron Reproductive biology characterististics of invasive alien plant Oenothera rosea Early Performances of Eight Provenances of Choerospondias axillaris Variation and Stability of Seed Yield, Fall-off Process, Seed Size and Form in Live Oak Preliminary Study on the Gaseous Nitrogenous Compounds Losses from Wheat Plant at Flowering and Seed Formation Stage