A Gur,
Y Mizrahi,
RM Samish
One-year-old apple plants of several rootstock clones, and grafted plants belonging to several scion cultivare, were grown in sand cultures for eight to ten weeks under conditions of constant root temperatures.
The optimal root temperature for development of the root system was 25°C for most rootstock clones, but 30°C for M 7, and the clones differed widely in the degree of damage caused to their roots by supraoptimal root temperature. The scion cultivar in grafted plants also contributed to the relative susceptibility of the whole plant. The order of relative susceptibility of clones was not maintained when root tip expiants, instead of whole plants, were cultivated at various temperatures. The temperature optimum for elongation of root tip expiants was considerably higher than that for root growth in intact plants.
The chlorophyll content of leaves was reduced by supraoptimal root temperature, but the degree of chlorophyll reduction in the different clones was about the same when compared with that at optimal root temperature. At this temperature, however, the clones differed greatly in chlorophyll content.
A Gur,
Y Mizrahi,
RM Samish
One-year-old apple plants of several rootstock clones, and grafted plants belonging to several scion cultivare, were grown in sand cultures for eight to ten weeks under conditions of constant root temperatures.
The optimal root temperature for development of the root system was 25°C for most rootstock clones, but 30°C for M 7, and the clones differed widely in the degree of damage caused to their roots by supraoptimal root temperature. The scion cultivar in grafted plants also contributed to the relative susceptibility of the whole plant. The order of relative susceptibility of clones was not maintained when root tip expiants, instead of whole plants, were cultivated at various temperatures. The temperature optimum for elongation of root tip expiants was considerably higher than that for root growth in intact plants.
The chlorophyll content of leaves was reduced by supraoptimal root temperature, but the degree of chlorophyll reduction in the different clones was about the same when compared with that at optimal root temperature. At this temperature, however, the clones differed greatly in chlorophyll content.