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Gregarious flowering of Dendrocalamus sikkimensis clumps located at Kerala Forest Research Institute campus and Field Research Centre, Veluppadam, Thrissur, Kerala initiated in August 2009. Observations were made on floral morphology, anthesis, pollination, pollen viability and germination and post flowering behaviour. The flowers were dichogamous, protogynous and closed. The inflorescence was a large leafy panicle, with stiff nodose branches bearing large globose heads. Pollens were numerous and monoporate. Ovary was sub globular, hairy with club shaped stigma. Anthesis occurred from 6.00 am onwards. High pollen viability (92 %) was observed in acetocarmine staining and in vitro pollen germination ranged from 3-74 per cent. The pollination was anemophilous. Flowering was followed by abundant seed production and subsequent drying and death of the culms. [ABSTRACT FROM AUTHOR]

The study in relation to loral biology conducted at Ludhiana (central plain region of Punjab, India) exhibited that Jatropha curcas lowered for two seasons viz. April till June and July till November. Male and female lowers opened 7 to 10 days after bud formation. Fruiting was visible 26.5 to 30.2 days after bud formation. Fruit setting ranged from 37.0 to 61.6% and the anthesis of male and female lowers occurred between 0600 to 0700 hours and 0700 to 0800 hours respectively. Anther dehiscence was observed after 0800 hours. Flowers were unisexual and male and female lowers were produced in the same inlorescence but female lowers were bigger. The male to female ratio was 13.4:1. Mean number of pollen per anther was 122.3 and ranged from 61.9 to 195.1. Mean pollen viability was 71.6%. Results of the breeding system showed fruit setting of 93.2, 72.2, 36.2 and 79.2% in cross pollination, self pollination, apomixis and open pollination respectively. [ABSTRACT FROM AUTHOR]

Study of reproductive biology and pollination ecology helps in understanding the life history patterns of species. Such a study brings to light the bottlenecks, if any, on account of which the individuals of the species are not able to reproduce in nature and ultimately helps in planning appropriate conservation strategies for the species under threat. The present study was aimed at examining the morphological and reproductive variance in Berberis lycium, a threatened ecological specialist growing within shrubberies and open hillsides of the North-Western Himalayas in India. B. lycium displays three different variants. Flowering period ranges from February to September. Pollen viability as reported on fluorescein diacetate and acetocarmine treatments was highest for variant I, while maximum pollen output was obtained for variant III. Pollen pistil interaction is brought by the movement of anther towards stigma. Fluorescence microscopy of hand pollinated club shaped stigma shows that the germinating pollen form a ring over the receptive adaxial surface. Pollination syndrome is entomophily. Variant II attracts a significantly large number of pollinators from diverse insect families. Breeding experiments reflect that plants are self-compatible and cross fertile. Reproductive output (% fruit set) was highest for variant II followed by III and I, respectively. This investigation helped to understand the effect of different biotic and abiotic constraints on the phenology and reproductive biology of the plant. The information generated so will enable conservationists to design appropriate strategies for its long-term survival and sustenance in nature. [ABSTRACT FROM AUTHOR]