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The aromatic odor of Plectranthus hadiensis var. tomentosus has been found to have the potential to improve physical and mental health of people in indoor environment, but its effectivess is reduced for that the release of volatile organic compounds from plants is susceptible to indoor environmental changes. The purpose of this study was to investigate the response of volatile organic compounds released by P. hadiensis var. tomentosus to common indoor environmental changes, and to provide a scientific basis for its efficient and sustainable application in building a comfortable pro-biotic environment to improve the physical and mental health of indoor personnel. Thus, the effects of four typical indoor environmental factors, such as air temperature, air relative humidity, CO2 concentration and light variation, on the release of volatile organic compounds from P. hadiensis var. tomentosus were investigated in this study. And the dynamic headspace and gas chromatography-mass spectrometry techniques were used to analyze the volatile organic compounds in different indoor environments with an environmental control device based on mixed-level orthogonal array design. The results were as follows:(1)Among the four typical indoor environmental factors of air temperature, air relative humidity, CO2 concentration and light condition, CO2 concentration and air temperature had greater effects on the release of volatile organic compounds from P. hadiensis var. tomentosus, while the effects of air relative humidity and light were weak.(2)For P. hadiensis var. tomentosus cultivated under normal photoperiod, an environmental condition with CO2 concentration of 500 μmol·mol-1, air temperature of 25 ℃ and air relative humidity of 60% was the most suitable for releasing volatile organic compounds from P. hadiensis var. tomentosus in the absence of light. Under this environmental condition, the total amount of volatile organic compounds released by P. hadiensis var. tomentosus was 86.23 μg·L-1·kg-1, and the content of biological active components with potentials for the positive intervention of physical and mental health was 78.03 μg·L-1·kg-1. In summary, the results suggest that when the aroma plant P. hadiensis var. tomentosus is used to build an indoor pro-biotic environment to maintain or improve the physical and mental health of people in indoor, the environmental conditions should be controlled properly, especially CO2 concentration and air temperature, so as to fully and efficiently produce the positive health benefits from P. hadiensis var. tomentosus. [ABSTRACT FROM AUTHOR]

‘Baoshi No.1', ‘Wanxiang' and ‘Fuwan No. 8' are the new longan varieties(lines)introduced from Fruit Research Institute of Fujian Academy of Agricultural Sciences to Nanning City, Guangxi in 2017. In order to study the local growth and development, flowering and fruiting regularity ‘Shixia' and ‘Guiming No.1', the main cultivars in Guangxi, were used as control to study the growth and development, yield, phenological period, flowering and fruit dropping regularity, and the relationship between the number of female flowers and temperature and humidity. The results were as follows: The plant growth and yield of the three introduced longan varieties(lines)after high grafting were similar to those of ‘Shixia'. The single panicle of ‘Baoshi No.1' was the heaviest, followed by ‘Fuwan No.8', and ‘Wanxiang' was similar to that of the two main cultivars; the fruit maturity stage of ‘Fuwan No.8' was the latest and the longest growth stage was 196 d, which was 15 d longer than ‘Guiming No.1'. The flowering stage of ‘Baoshi No.1' was the longest and ‘Wanxiang' was the shortest. The order of male and female flowers blooming of the three new varieties(lines)was “male-female-male-female-male”. The meeting time of male and female flowers of ‘Baoshi No.1' and ‘Fuwan No.8' was longer, which was 18-19 d. The three new longan varieties(lines)had three peak stages of fruit dropping in Nanning, and the fruit dropping mainly occurred in the second physiological fruit dropping stage in June. The results showed that the numbers of female flowers of three new longan varieties(lines)were closely related to the temperature and humidity before flowering. Within a certain range of temperature and humidity before and after flowering, higher temperature and lower air humidity were beneficial to female flower blooming of ‘Baoshi No.1' and ‘Fuwan No.8', while lower temperature and higher air humidity were beneficial to female flower blooming of ‘Wanxiang'. On the whole, the three introduced Fujian longan varieties(lines)can normally bloom and bear fruit in Guangxi, ‘Baoshi No.1' is earlier, ‘Fuwan No.8' is the latest, the meeting time of male and female flowers is long, and the fruit-dropping rate is low. [ABSTRACT FROM AUTHOR]

In order to understand the dynamic variations of photosynthetic capacity of Rhododendron to adapt to environmental factors in different seasons. Rhododendron delavayi, widely introduced and cultivated, was planted in a 2-gallon plastic basin in the open field. The dynamic variations of photosynthetic characteristics and influencing factors in different growth phases were investigated by the technique of gas exchange and chlorophyll fluorescence. The results were as follows: The growth cycle of R. delavayi were almost overlaps with photosynthetic variation at Kunming area. The variations of photosynthetic characteristics reflected the variations of growth cycle. In the net early growth period from May to July, the photosynthetic rate(Pn)increased rapidly, the stomatal conductance(Gs)was the decisive factor affecting (Pn). The relative humidity of air(RH)had a significant indirect effect on (Pn) by affecting Gs and transpiration rate(Tr). The (Pn) and growth could be stimulated by increasing RH at this phase. In the peak growth period from July to October, the RH, (Pn) and Gs of R. delavayi were high and stable. However, lower air temperature(AT)in this phase was a unique climate character in Kunming area. Low AT became an important factor affecting photosynthetic capacity at this phase, and increasing AT could improve (Pn) and promote the growth of R. delavayi. In the late growth phase after October, AT and RH decreased rapidly, stomata closed gradually, the maximum quantum efficiency of photosynthetic system Ⅱ(Fv/Fm)and (Pn) were declined. Gs and Fv/Fm were the main factors affecting photosynthesis at this stage. Our results can provide important references for the scientific cultivation and popularization of R. delavayi. [ABSTRACT FROM AUTHOR]