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[ Objective] The presnet paper aimed to understand flowering habits and pollen fenility of Pueraria lobata, and provide reference for improving the success rate of P. lobata cross pollination. [ Method] In Longzhou county, Guangxi, the bud development process of P. lobata inflorescences were observed every day after it was formed, marked the inflorescences that were about to open in the full bloom period, continuously observed the blooming process of the flowers and recorded the blooming time and weather conditions of the day. Triphenyl tetrazolium chloride (TIC) staining and 12 -KI staining were used to detect pollen activity of P. lobata at different bud stages ( half stretch period, presentation period, half period and blooming period), and the pollen with the strongest pollen viability was selected to carry out the pollen germination test according to the pollen viability measurement results. [ Result] In Longzhou county, Guangxi, P. lobata began to flower on October 16, reached the flowering stage on October 20, and the last flowering stage was from November 2 to November 5. The flowering time of P. lobata was mainly from 15: 10 to 15 :40 every day, and the flowering powder was affected by the weather conditions. Flowering was early when the weather was clear and the temperatute was high, while flowering was delayed when the temperature was low and cloudy and rainy. The pollen activity of P. lobata in different bud stages ( half stretch period, presentation period, half period and blooming period) detected by 12 -KI staining method were 82. l %,95. 3%,93. 5% and 92. 7%,respectively, which were significantly higher than TIC staining method ( P <0. 05, the same as below), and it was more suitable for the detection of the pollen activity of P. lobata. Most of the anthers of the P. lobata flower have already loosened their powder at the beginning of the presentation period, and the stigma was wrapped with large amount. The pollen vitality in the presentation period detected by 12-KI staining was the highest, reaching 95. 3%, which was significantly higher than the other three stages. The pollen quantity and pollen vitality remained at a high level from half stretch period to blooming period. In the medium containing 15 % sucrose, the germination rate of P. lobata pollen was the highest( 36. 23 % ), which was significantly higher than that of the other three sucrose concentrations. [ Conclusion]The 12 -KI staining method can quickly detect the pollen viability of P. lobata. The pollen viability of P. lobata was maintained at a high level from half period to blooming period, and the germination rate was the highest in the medium containing 15% sucrose in sunny weather. 12 -Kl staining method can be used to detect pueraria pollen viability rapidly. Pollen viability of P. lobata remained at a high level from bud opening stage to blooming stage, and pollen at a suitable period could be selected for cross-pollination according to weather conditions to improve the success rate of cross-pollination. [ABSTRACT FROM AUTHOR]

China is one of the five major distribution regions of Impatiens in the world, with more than 270 species distributed all over the country, especially in limestone areas such as Yunnan, Guizhou and Guangxi. In order to explore pollination ecology of Impatiens uliginosa, we conducted the following experiments: observing the floral traits and floral phenology, measuring the nectar volume and sugar concentration, counting pollen viability, deposition and removal, carrying out pollination treatments and recording floral visitors and their behavior. Results show that the average life span of a single flower is 3.23±0.68 d. The male and female phase lasted for 1.70±0.06 d and 1.53±0.63 d. The amount of nectar per flower is 6.97±0.47 ul and sugar concentration of nectar is 36.58±0.82%, respectively. Stigma is receptive on the first day of anthesis. Pollen viability is strongest on the second day of anthesis. The pollen-ovule ratio (P/O) is 3974.28±105.07. We investigated the contributions of different floral visitors. Bombus sp., Apis dorsata, Lobocla proxima, Ant sp. and Ephydra sp. are diurnal visitors. However, Bombus sp. is the most effective pollinator of I. uliginosa. Pollination treatments indicated that I. uliginosa is self-compatible but completely relies on pollinators for pollination. There is no restriction on pollination in the field and I. uliginosa can avoid inbreeding depression. This study is of great significance to enrich the biological data of pollination and protect the biodiversity of Impatiens. [ABSTRACT FROM AUTHOR]

Camellia pubipetala is an endemic and endangered species with small and isolated populations occurring only in karst regions in Guangxi of south China. To understand the reproductive biology of C. pubipetala and its possible influences upon its endangered status, its breeding system and pollination ecology were studied in the Longhushan (LHS) and Longzhao (LZ) populations of this species. The flowering duration of the C. pubipetala populations spanned from late January to early April and anthesis of a single flower usually lasted 5–7 days. This species is homogamous, and the pollen and stigma are viable throughout anthesis. Each bagged flower could secrete 141.5 μL of nectar at a sugar concentration of 25.0% during anthesis. The observed high pollen/ovule ratio, and the results of hand‐pollination experiments indicated that this species obligately outcrosses. Open pollination resulted in a significantly decreased fruit set (6.7%) and seed set (38.9%) compared to supplementary pollination treatment (23.3% and 64.7%, respectively), which is indicative of a pollen limitation in the process of pollination. The primary pollinator of C. pubipetala is the sunbird Aethopyga christinae and its visiting frequency is quite low, whereas the honeybee Apis cerana is only an occasional pollinator in wild populations. Low reproductive rates in C. pubipetala were found to be a consequence of few species of pollinators and their low visiting frequency. Pollen limitation may be a crucial factor that contributes to the endangered nature of this species. Artificial pollination and the release of pollinators are effective ways to increase the fruit and seed yield of this species. [ABSTRACT FROM AUTHOR]