Effects of shading on leaf physiology and morphology in the ‘Yinhong’ grape plants

Abstract

Shading is a practical measure to reduce the heat stress to grape trees in the summer. However, inappropriate shading will cause the reduction in leaf photosynthesis and consequently the retardation of growth for the plants or the loss of fruit yield and quality for the mature grape trees. In this study we have used 1-year-old ‘YinHong’ grape plants growing under different levels of shading, ranging from full sunlight 0% to 80% reduction, to investigate their growth, physiological and biochemical responses. The results show that shading rate =45% did not significantly affect grape growth. Shading over 45% reduction of the full sunlight, the growth of the grape plants were started to be inhibited. In addition, soluble protein content, the activities of catalase (CAT), peroxidase (POD) and superoxide dismutase (SOD), chlorophyll content, net photosynthetic rate (Pn), stomatal conductance (Gs), intercellular CO2 concentration (Ci), transpiration rate (Tr), PSII photochemical efficiency (Fv/Fm), PSII potential activity1(Fv/Fo) and photochemical quenching (qP) were decreased, whereas free proline, malondialdehyde (MDA) content, the non-photochemical quenching coefficient (qN) and the ratio of the palisade/spongy tissue were gradually increased. In particular, significant changes in plant growth, photosynthetic and the other physiological and biochemical characteristics were observed under a strong shading.

Technological Effectiveness of Chelated Micronutrient Fertilizers in Leaf Treatments Inducing Grapes Resistance to Biotic and Abiotic Stresses

“…Photosynthetic activity often plays a key role in plant resistance to adverse external environmental factors; the important role of the photosynthetic pigments concentration for crop formation and the accumulation of plant bioenergy in agroecosystems is known. Photosynthesis of grape plants, being the basis of the production process, depends on many natural and anthropogenic environmental factors being geographically and climatically related [21,22,23]. Of particular importance is the photosynthesis relevance for plants that are constantly exposed to stress [24].…”

Morphophysiological aspects of young Calotropis procera plants submitted to different shading levels

“…The Fv/Fm represents the energy conversion efficiency of light in the PSII reaction center, while the Fv/F0 ratio represents the activity of PSII. In this perspective, leaves of plants developed in full sun have a greater number of components of the photosynthetic apparatus, providing photosynthetic capacity per unit of leaf area [27].…”

Colored Shade Nets can Relieve Abnormal Fruit Softening and Premature Leaf Senescence of “Jumeigui” Grapes during Ripening Under Greenhouse Conditions

“…Wu et al 22 found that shading can prevent heat-stress damage of grape plants in summer. However, in our study, we examined perennial fruit vines and used a phased shading treatment to achieve ideal cooling and light transmission.…”