[Objective] Iron deficiency is one of the most important crop element deficiencies in the Loess Plateau of northwestern China. The selection for crop cultivars that are tolerant to low iron levels could be one of the ...[Objective] Iron deficiency is one of the most important crop element deficiencies in the Loess Plateau of northwestern China. The selection for crop cultivars that are tolerant to low iron levels could be one of the approaches to solving the problem and improving crop production. [Method] Three major apple root stock species （Malus prunifolia, Malus sieversii and Malus baccata） were selected to evaluate their tolerance to iron defciency in hydroponic system. A 3×2 factorial pot experiment was conducted with three replicates in a greenhouse at Gansu Agricultural University, Lanzhou, China. [Result] The SOD, POD and CAT activities in roots and stems of the 3 root stock species in Fe-defcient Hoagland solution decreased, however Malus sieversii got the less reduction and had better root architecture and growth than the other species. The aboveground biomass, plant height, chlorophyll content, total root length and lateral root number were correlated positively with iron-defciency stress tolerance. The species’ tolerance to iron-defciency from high to low was M. sieversii’s〉M. baccata’s〉M. prunifolia’s. Moreover, the improvement of some morphological features such as root length, above-ground biomass, plant height and lateral root number in apple could be conducive to breeding cultivars with tolerance to iron-defciency stress. [Conclusion] Malus sieversii had better tolerance to iron-defciency stress than the others in this study.展开更多
The root development of Actinidia chinensis planUets was studied in exposure to environmental stress of mechanical vibration at respectively 1 Hz, 2 Hz, 3 Hz, 4 Hz and 5 Hz. The plantlets exposed to vibration stimuli ...The root development of Actinidia chinensis planUets was studied in exposure to environmental stress of mechanical vibration at respectively 1 Hz, 2 Hz, 3 Hz, 4 Hz and 5 Hz. The plantlets exposed to vibration stimuli at all those frequencies have a larger total number and a larger total length of roots and a smaller permeability of root plasma-membrane, compared with those cultivated in an environment without vibration stress. Vibration at respectively 1 Hz, 2 Hz, 3 Hz and 4 Hz enhances root activity and the 3 Hz vibration is the most favorable. There is an obvious negative correlation between root activity and permeability of root plasma-membrane. The effects may be explained by the likelihood that mechanical Vibration at an appropriate frequency facilitates roots＇ absorbing water and minerals which are indispensable to inducing and synthesizing in roots some active substances favorable to growth. Nevertheless, overstress damages the integrity of root plasm-membrane, increases the permeability, and results in the disability of protecting root cells.展开更多
基金Supported by University Research Project of Education Dpartment(2018A-035)~~
文摘[Objective] Iron deficiency is one of the most important crop element deficiencies in the Loess Plateau of northwestern China. The selection for crop cultivars that are tolerant to low iron levels could be one of the approaches to solving the problem and improving crop production. [Method] Three major apple root stock species （Malus prunifolia, Malus sieversii and Malus baccata） were selected to evaluate their tolerance to iron defciency in hydroponic system. A 3×2 factorial pot experiment was conducted with three replicates in a greenhouse at Gansu Agricultural University, Lanzhou, China. [Result] The SOD, POD and CAT activities in roots and stems of the 3 root stock species in Fe-defcient Hoagland solution decreased, however Malus sieversii got the less reduction and had better root architecture and growth than the other species. The aboveground biomass, plant height, chlorophyll content, total root length and lateral root number were correlated positively with iron-defciency stress tolerance. The species’ tolerance to iron-defciency from high to low was M. sieversii’s〉M. baccata’s〉M. prunifolia’s. Moreover, the improvement of some morphological features such as root length, above-ground biomass, plant height and lateral root number in apple could be conducive to breeding cultivars with tolerance to iron-defciency stress. [Conclusion] Malus sieversii had better tolerance to iron-defciency stress than the others in this study.
基金Funded by the Natural Science Foundation of China (No. 39770206).
文摘The root development of Actinidia chinensis planUets was studied in exposure to environmental stress of mechanical vibration at respectively 1 Hz, 2 Hz, 3 Hz, 4 Hz and 5 Hz. The plantlets exposed to vibration stimuli at all those frequencies have a larger total number and a larger total length of roots and a smaller permeability of root plasma-membrane, compared with those cultivated in an environment without vibration stress. Vibration at respectively 1 Hz, 2 Hz, 3 Hz and 4 Hz enhances root activity and the 3 Hz vibration is the most favorable. There is an obvious negative correlation between root activity and permeability of root plasma-membrane. The effects may be explained by the likelihood that mechanical Vibration at an appropriate frequency facilitates roots＇ absorbing water and minerals which are indispensable to inducing and synthesizing in roots some active substances favorable to growth. Nevertheless, overstress damages the integrity of root plasm-membrane, increases the permeability, and results in the disability of protecting root cells.
