The response of Kousa dogwood （Cornus kousa Buerg.） to extreme stresses was investigated by RGB image analysis in the hot, dry and windy summer in 2007 in Yamaguch, Japan. Results show that tip and margin leaf scorc...The response of Kousa dogwood （Cornus kousa Buerg.） to extreme stresses was investigated by RGB image analysis in the hot, dry and windy summer in 2007 in Yamaguch, Japan. Results show that tip and margin leaf scorch was observed on many Kousa dogwood trees and clearly dark brown defense barrier appeared on scorched leaves. The defense barrier withdrew back from distal to proximal gradually until successful control of scorching, and left a series of unsuccessful defense traces. By responsive analysis of leaf color homogeneity with RGB image analysis method, a sharp logistic equation was obtained for the relative green/luminance （RGL） value of scorched leaves. By the meteorological analysis, the occurrence of dogwood leaf scorch-back was almost synchronous with the aridity peak period. It sug- gested that during the sudden aridity increment the extreme water stresses induce the defense response of Kousa dogwood tree to shear the excessive transpiration leaf area, and prevent the rest of the trees from further water loss. Image pixet analysis showed that 40.2% leaf area of sampled dogwood trees was reduced through the partial leaf scorch-back by the end of August in 2007. In contrast, only 13.2% leaf area was reduced from the same trees in 2008, for the reason of sufficient precipitation during first half year. In any case, the Kousa dogwood trees indeed reduced their transpiration surface area and appeared a surface reduction pattern differing from those shedding leaves or withering all the aboveground. Based on desiccation process analysis, it is considered that the interaction of the leaf dried back and the self-defense response was the key of the transpiration surface reduction （TSR） of Kousa dogwood during sudden hot and droughty stresses.展开更多
As the human population increases globally,the food animal industry has not been spared from the monumental demand for edible animal products,particularly meat.This has necessitated the simulta-neous expansion of the ...As the human population increases globally,the food animal industry has not been spared from the monumental demand for edible animal products,particularly meat.This has necessitated the simulta-neous expansion of the productivity of the animal sector to meet the ever-growing human needs.Although antibiotics have been used in food animal production with commendable positive impacts on their growth performance,their sole contributive factor to the increasing incidence of antimicrobial resistance has ushered the strict restrictions placed on their use in the animal sector.This has handed a setback to both animals and farmers;thus,the intense push for a more sustainable antibiotic alternative for use in animal production.The use of plants with concentrated phytogenic compounds has gained much interest due to their beneficial bioactivities,including antioxidant and selective antimicrobial.While the reported beneficial activities of phytogenic additives on animals vary due to their varying total polyphenol concentrations(TPC),red osier dogwood(ROD)plant materials boast of high TPC with excellent antioxidant prowess and growth improvement capacities compared to some plant extracts commonly used in research.However,its adoption in research and commercial scale is still low.Thus,the present review aims to provide concise information on the dietary potential of ROD plant materials in animal feeding.展开更多
文摘The response of Kousa dogwood （Cornus kousa Buerg.） to extreme stresses was investigated by RGB image analysis in the hot, dry and windy summer in 2007 in Yamaguch, Japan. Results show that tip and margin leaf scorch was observed on many Kousa dogwood trees and clearly dark brown defense barrier appeared on scorched leaves. The defense barrier withdrew back from distal to proximal gradually until successful control of scorching, and left a series of unsuccessful defense traces. By responsive analysis of leaf color homogeneity with RGB image analysis method, a sharp logistic equation was obtained for the relative green/luminance （RGL） value of scorched leaves. By the meteorological analysis, the occurrence of dogwood leaf scorch-back was almost synchronous with the aridity peak period. It sug- gested that during the sudden aridity increment the extreme water stresses induce the defense response of Kousa dogwood tree to shear the excessive transpiration leaf area, and prevent the rest of the trees from further water loss. Image pixet analysis showed that 40.2% leaf area of sampled dogwood trees was reduced through the partial leaf scorch-back by the end of August in 2007. In contrast, only 13.2% leaf area was reduced from the same trees in 2008, for the reason of sufficient precipitation during first half year. In any case, the Kousa dogwood trees indeed reduced their transpiration surface area and appeared a surface reduction pattern differing from those shedding leaves or withering all the aboveground. Based on desiccation process analysis, it is considered that the interaction of the leaf dried back and the self-defense response was the key of the transpiration surface reduction （TSR） of Kousa dogwood during sudden hot and droughty stresses.
基金Natural Sciences and Engineering Research Council of Canada(34288),Canadian Poultry Research Council(38335),MITACS(38335),Dalhousie University(34741).
文摘As the human population increases globally,the food animal industry has not been spared from the monumental demand for edible animal products,particularly meat.This has necessitated the simulta-neous expansion of the productivity of the animal sector to meet the ever-growing human needs.Although antibiotics have been used in food animal production with commendable positive impacts on their growth performance,their sole contributive factor to the increasing incidence of antimicrobial resistance has ushered the strict restrictions placed on their use in the animal sector.This has handed a setback to both animals and farmers;thus,the intense push for a more sustainable antibiotic alternative for use in animal production.The use of plants with concentrated phytogenic compounds has gained much interest due to their beneficial bioactivities,including antioxidant and selective antimicrobial.While the reported beneficial activities of phytogenic additives on animals vary due to their varying total polyphenol concentrations(TPC),red osier dogwood(ROD)plant materials boast of high TPC with excellent antioxidant prowess and growth improvement capacities compared to some plant extracts commonly used in research.However,its adoption in research and commercial scale is still low.Thus,the present review aims to provide concise information on the dietary potential of ROD plant materials in animal feeding.
