No abstract

Taking the leaves of five Machilus species as a research object, they are Machilus oreophila, Machilus chinensis, Machilus microcarpa, Machilus lichuanensis and Machilus suaveolens. By measuring leaf surface area, cell length and width , the total dust retention, pH value of retention fluid and the content of Pb, Cr, Fe, Cu and Cd of metallic elements were measured, and compare the dust retention of five plant seedling leaves ability. The results showed that: the leaves of different kinds of Machilus have different dust abilities. Comprehensive analysis can be obtained from five kinds of Machilus dust ability in descending order of M. suaveolens > M. lichuanensis > M. chinensis > M. microcarpa > M. oreophila.   ********* In press - Online First. Article has been peer reviewed, accepted for publication and published online without pagination. It will receive pagination when the issue will be ready for publishing as a complete number (Volume 47, Issue 4, 2019). The article is searchable and citable by Digital Object Identifier (DOI). DOI link will become active after the article will be included in the complete issue. *********

The aim was to study exogenous GB on cold resistance of Phoebe microphylla. Taking one-year-old Phoebe microphylla seedlings as materials, effects of different concentrations (50. 100. 150 mmol•L -1 ) exogenous GB on cold resistance of Phoebe microphylla under low temperature. Under low temperature stress, foliar spraying of different concentrations GB significantly decreased malonaldehyde (MDA) content, Relative conductivity, and increased chlorophyll, Soluble protein, Soluble sugar, peroxidase (POD), superoxide dismutase (SOD) activities in Phoebe microphylla. Among 3 kinds of GB concentrations, 150 mmol•L -1 GB was the best for Phoebe microphylla on cold resistance. A certain concentration GB preprocessing mitigates the harm of low temperature stress on Phoebe microphylla seedling, and improves their ability of cold resistance.

Seedlings of Taxus chinensis var. mairei were used as experimental materials to study the adaptation of Piriformospora indica to this plant under water stress. The materials were divided into two groups, namely, with or without inoculation with P. indica. Each group was subjected to four different levels of water stress. Vitality and physiological and biochemical indexes of the roots of T. chinensis var. mairei were regularly measured. Under water stress, T. chinensis var. mairei had significantly decreased root vitality; root vitality was higher in inoculated roots than in uninoculated roots. Under intense water stress, the inoculated roots had a higher soluble sugar content than the uninoculated roots. Under water stress, T. chinensis var. mairei experienced decreased activity of aerobic respiratory metabolic enzymes. The activity of anaerobic respiratory metabolic enzymes and alcohol dehydrogenase initially increased and then decreased, whereas that of lactate dehydrogenase increased. The inoculated roots had a higher activity of respiratory metabolic enzymes than the uninoculated roots. As water stress was further intensified, the roots had significantly decreased activity of aerobic respiratory metabolic enzymes and significantly increased activity of anaerobic respiratory metabolic enzymes. The activity of respiratory metabolic enzymes decreased faster in the uninoculated roots than in the inoculated roots. This study demonstrated that Piriformospora indica plays a positive role in enhancing the antihypoxic ability of T. chinensis var. mairei, thereby alleviating plant damage due to water stress.