Morpho-physiological classification of seeds and morphology of fruits and seedlings of Richeria grandis

Abstract The objective was to describe and characterize the fruit morphology, seeds, seedlings and germination of Richeria grandis. Mature fruits were collected from matrix trees located in gallery forests. After, morphological descriptions were performed. Biometric measurement of fruits and seeds were carried out. A total of 650 seeds were randomly separated, with 20% being used for germination and humidity testing on the same day of collection and the others stored for 5, 10, 15 and 20 days. The germination test was performed in a gerbox, conducted in a laboratory chamber of the type B.O.D (biochemical oxygen demand) with a photoperiod of 12h and a temperature of 25 ºC ± 1 ºC. Periodic observations were made to monitor the development of the seedlings until the first germinated seeds reached the full seedling stage. The fruit of R. grandis is a simple, dry, capsule type septifraga, dehiscent and schizocarpic, with average length of 16.24 mm and an average width of 8.57 mm. The seed is an ellipsoid shape, containing a sarcotesta and has an average length of 7.40 mm and an average width of 4.57 mm. R. grandis presents recalcitrant seeds, which emerge in a Phanero-epigene-foliaceous manner. The radicle breaks the integument on the second day after sowing, the collection is evidenced on the 10th day, separating the primary root from the hypocotyl. At day 16, the cotyledons expand from the forehead, positioned at a 90º angle to the hypocotyl. The protophyll and the epicotyl appear only after the 50th day, characterizing the complete seedling.

摘要 本研究旨在描述并表征大叶格脉树（Richeria grandis）的果实形态、种子、幼苗及萌发特性。成熟果实采自河岸林内的母树，随后开展形态学描述，并对果实与种子进行形态计量测定。共随机选取650粒种子，其中20%于采集当日用于萌发试验与湿度检测，剩余种子分别储存5、10、15及20天。萌发试验在发芽盒中开展，于生化需氧量（B.O.D）型实验室培养箱内进行，设置光照周期12h，温度为25℃±1℃。定期观测幼苗生长情况，直至首批萌发种子发育至完整幼苗阶段。大叶格脉树的果实为单生干燥蒴果，属室背开裂的分果，平均长16.24 mm，平均宽8.57 mm。种子呈椭圆形，具肉质种皮，平均长7.40 mm，平均宽4.57 mm。该树种产生顽拗性种子，萌发方式为显子叶出土叶状萌发。播种后第2天，胚根突破种皮；播种后第10天，相关结构显现，初生根与下胚轴发生分离。播种后第16天，子叶从顶端展开，与下胚轴呈90°夹角；播种后第50天，初生叶与上胚轴出现，至此幼苗发育完全。