Reproductive biology of Solanum sisymbriifolium Lamk . ( Solanaceae ) in Tripura , North-east India

Reproductive biology of angiosperms has its focus on MATERIALS AND METHODS phenology, pollination biology, pollen-pistil interaction and The present study was carried out on ten marked plants of breeding systems. These are valuable for basic and applied S. sisymbriifolium growing at Tripura University campus in research, having implications to ecological and evolutionary natural conditions. Observations were recorded every day on studies as well as agriculture and conservation biology. The flowering phenology, pollen biology, number of pollen and physiology of reproduction in most of the flowering plants is ovules/flower and pollen-ovule ratio and breeding system. closely under the control of environmental factors (Taiz and Flowering phenology—The number of flowers on ten Zeiger 2003). The environment in which an organism lives marked plants were counted periodically throughout the affects its reproductive success (Sedgley and Griffin 1989). flowering period. Initiation, peak and end of flowering were Environment exerts considerable influence on flowering, registered following the procedure after Dafni (1992). pollen fertility, in vitro pollen germination and fruiting in Number of open flowers/plant/day was counted. Time of plants (Shivanna 2003). opening of flowers, anther dehiscence, and stigma receptivity Solanum sisymbriifolium Lamk. commonly known as was recorded. Stigma receptivity was determined by “sticky nightshade” is an important medicinal plant belonging examining 100 stigmas at different stages of development for to the family Solanaceae. The plant is grows wild in the state stigmatic secretion. Formation of fruits was observed Tripura and it occurs mostly in dry places, as a weed along periodically in tagged floral buds on marked plants. The road sides and waste lands. Various medicinal properties are longevity of flowers was observed by the method after Gill et attributed to it particularly the fruits and flowers are used as al. (1998). analgesic, in the synthesis of corticosteroids and oral Pollen production/anther/flower—Mature anthers were contraceptives (Ferro et al. 2005). The ethanol extract of crushed in lactophenol-glycerine with aniline blue. A known leaves also shows neuro-pharmacological, anti-diarrheal, and dilution was placed on the grid and 10 replicate counts were cytotoxic activities (Serker et al. 2013). In spite of its made using a hemocytometer (Barrett 1985). Morphology of excessive use for medicinal purposes and wide distribution, pollen was studied after acetolysis (Erdtman 1960). The size this species is gradually decreasing due to habitat of the pollen grains (for radio symmetric ones the diameter in fragmentation and by increasing urbanization and the polar view, and for bilateral ones the polar and equatorial industrialization. So, there is an urgent need for its axes) was measured in glycerine jelly (Wodehouse 1935) conservation and it can be achieved by understanding its using standard ocular micrometer. reproductive biology. Floral biology of Solanum Meiosis—The young flower buds were fixed in 1: 3 acetic sisymbriifolium have been studied earlier (Biswas et al. 2013). alcohol for 24 h and meiotic behaviour was studied by squash However, reproductive biology of this medicinally important technique using 2% acetic carmine (Belling 1926). plant has not been studied so far in Tripura and therefore, the