The optimal drainage line of potted flowers of soilless culture

Water is the source of life. China ranks No.13 among the water shortage countries. The most of the water is utilized in agriculture, while the utilization rate of irrigation water is only 40%, so it is very important to study on the theory and technology on high efficient water utilization. The purpose for this study is to find out the optimal drainage line on potted flowers through the analysis of experimental results of Aglaonema modestum and Rhododendron simsii Planch in different drainage lines.

Screening of High-quality Substrate for Soilless Culture of Begonia cucullata Willd.

In order to investigate a better soilless culture medium and the possibility of grass clippings as alternative substrate for peat moss to grow Begonia cucullata Willd. in pots, the seedlings of widely cultivated B. cucullata were grown in pots with eight types of soilless substrates： T1（peat： perlite=1：1）, T2（peat： perlite： pine bark=1：1：1）, T3（corn stover： perlite： pine bark=1：1：1）, T4（corn stover： perlite： pine bark=2：1：1）, T5（grass clipping： perlite： pine bark=1：1：1）, T6（grass clipping： perlite：pine bark=2：1：1）, T7（vermiculite： perlite： pine bark=1：1：1） and T8（vermiculite： perlite： pine bark=2：1：1）, respectively, in a shade house of Shanghai Chenshan Botanical Garden to evaluate plant growth performance. The results showed that the stem diameter of B. cucullata increased significantly from day 30 to day 60 after potting,and the plant height, leaf number and leaf area increased largest from day 60 to day 90 after potting in all treatments. The growth of plants performed best in T6,with the highest branch number, leaf thickness, flower number, aboveground fresh and dry weights and relative chlorophyll content. Therefore, the substrate with grass clipping： perlite： pine bark=2：1：1 was the best culture medium for growing B. cucullata in this study, and the grass clippings could replace peat moss as alternative substrate for growing B. cucullata in containers.

The Effect of Photosynthetic Active Radiation and Temperature on Growth and Flowering of Ten Flowering Pot Plant Species

Hibiscus rosa-sinensis, Rosa sp. (miniature roses), Sinningia speciosa, Gerbera hybrida, Kalanchoe blossfeldiana, Hydrangea, Begonia x hiemalis, Calceolaria, Cyclamen persicum and Pelargonium domesticum were grown at six photon flux densities (85, 130, 170, 215, 255 and 300 μmol·m-2·s-1, PFD) during lighting periods of 20 h·day-1 at three air temperatures (18°C, 21°C and 24°C) in midwinter at latitude 59° north. This corresponded to photosynthetic active radiations (PAR) ranging from 6.1 to 21.6 mol·m-2·day-1. Time until flowering decreased in all species except Cyclamen when the temperature increased from 18°C to 21°C, particularly at lower PFD levels. A further increase in temperature, from 21°C to 24°C, clearly decreased time until flowering in six of the ten tested species. Generally, this represented a reduction in the time until flowering between 20% and 40%. The dry weight of the plants at time of flowering increased up to 170 μmol·m-2·s-1 PFD (12.2 mol·m-2·day-1 PAR) in Hibiscus, miniature rose, Kalanchoe and Pelargonium, while the dry weight reached a maximum at 85 to 130 μmol·m-2·s-1 PFD mol·m-2·day-1 (6.1 to 9.4 mol·m-2·day-1)in the other species. Based on the present results a PAR level of 6 to 8 mol m-2·day-1 is recommended for Calceolaria and Cyclamen, of 8 to 10 mol·m-2·day-1 for Sinningia, Gerbera, Kalanchoe, Hydrangea and Begonia, of 10 to 12 mol·m-2·day-1 for Pelargonium and of 12 to 15 mol·m-2 day-1 for Hibiscus and miniature roses.