The main purpose of this research is to provide a theoretical foundation for the screening of drought-resistant soybean varieties and to establish an efficient method to detect the PSII actual photochemical quantum yields efficiently. Three soybean varieties were compared in this experiment after 15 d when they were planted in a greenhouse. These varieties were then exposed to light drought stress (LD) and serious drought stress (SD) conditions. With five times' measurement, chlorophyll fluorescence and soil-plant analysis development considered as the main basis for this study. Several parameters in SD conditions significantly reduced, such as net photosynthetic rates (Pn), stomatal conductance (Gs), PSII primary light energy conversion efficiency (Fv/FM), PSII actual photochemical quantum yields [Y(II)], photochemical quenching coefficient (qP) and non-photochemical quenching coefficient (qN). The soybeans in the seedling stage adapted to the inhibitory effect of drought stress on photosynthesis through stomatal limitation. Under serious drought stress, non-stomatal limitation damaged the plant photosynthetic system. The amplitudes of Pn and Y(II) of drought-resistant Qihuang 35 were lower than those of the two other varieties. Based on the data of this study, a new method had been developed to detect Y (II) which reflected the photosynthetic capacity of plant, R=0.85989, u=0.048803 when using multiple linear regression, and R=0.84285, u=0.054739 when using partial least square regression. of drought stress on photosynthesis and chlorophyll fluorescence images of soybean (Glycine max) seedlings. Int J Agric & Biol Eng, 2018; 11(2): 196-201.

Drought stress is a major environmental constraint for plant growth. Climate-change-driven increases in ambient temperatures resulted in reduced or unevenly distributed rainfalls, leading to increased soil drought. Carex duriuscula C. A. Mey is a typical drought-tolerant sedge, but few reports have examined the mechanisms conferring its tolerant traits. In the present study, the drought responses of C. duriuscula were assessed by quantifying activity of antioxidant enzymes in its leaf and root tissues and evaluating the relative contribution of organic and inorganic osmolyte in plant osmotic adjustment, linking it with the patterns of the ion acquisition by roots. Two levels of stress—mild (MD) and severe (SD) drought treatments—were used, followed by re-watering. Drought stress caused reduction in a relative water content and chlorophyll content of leaves; this was accompanied by an increase in the hydrogen peroxide (H2O2) and superoxide (O2−) contents in leaves and roots. Under MD stress, the activities of catalase (CAT), peroxidase (POD), and glutathione peroxidase (GPX) increased in leaves, whereas, in roots, only CAT and POD activities increased. SD stress led to an increase in the activities of CAT, POD, superoxide dismutase (SOD), and GPX in both tissues. The levels of proline, soluble sugars, and soluble proteins in the leaves also increased. Under both MD and SD stress conditions, C. duriuscula increased K+, Na+, and Cl− uptake by plant roots, which resulted in an increased K+, Na+, and Cl− concentrations in leaves and roots. This reliance on inorganic osmolytes enables a cost-efficient osmotic adjustment in C. duriuscula. Overall, this study revealed that C. duriuscula was able to survive arid environments due to an efficient operation of its ROS-scavenging systems and osmotic adjustment mechanisms.

This paper explores conceptions of islands in Ancient and Imperial China. From at least the 3rd Century BCE, mainland Chinese culture regarded islands as sacred, unapproachable fairylands, home to the elixir of immortality. This inspired a trend for voyages in search of mythological sacred islands as well as a landscape architecture trend for constructing artificial islands in imperial palace gardens. Over time, Taoism came to associate islands with the home of the gods, and Chinese Buddhism came to associate islands with dragon kings. As China's maritime activity increased, so, too, did fiction regarding islands of adventure. These conceptions of sacred islands and islands of adventure coexisted with the use of actual islands as places of political exile. By exploring island traditions in Chinese literature, this paper adds to our knowledge of how and why people throughout history have regarded islands and archipelagos as special. This paper also pursues a decolonial island studies by challenging some of the Eurocentric and imperialistic tendencies within the research field, which have led to a privileging of Western island metaphors and understandings.

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