Claim · model-written summary
In unheated ears, apical kernel endosperm had 24% smaller mature dry weight than basal kernel endosperm.
Zea maysVerbatim
e0“maize (Zea mays L.)”
e1“In controls, apical-kernel endosperm had 24% smaller dry weight at maturity”
e2“Apical florets of maize (Zea mays L.) ears differentiate later than basal florets and form kernels which have lower dry matter accumulation rates.”
e3“In controls, apical-kernel endosperm had 24% smaller dry weight at maturity, lower concentration of sucrose, and lower activity of ADP-Glc starch synthase than basal-kernel endosperm, whereas ADP-Glc-pyrophosphorylase (ADPG-PPase) activities were similar.”
e4“In tip-heated ears apical-kernel endosperm had the same growth rate and final weight as basal-kernel endosperm and apical kernels had higher sucrose concentrations, higher ADP-Glc starch synthase activity, and similar ADPG-PPase activity.”
e5“Total grain weight per ear was not increased by tip-heating because the increase in size of apical kernels was partially offset by a slight decrease in size of the basal- and middle-position kernels.”
Title
Zoe Kolovou PLANT PHYSIOLOGY 2013. doi:10.1104/pp.79.3.852
Other claims from this paper (18)
- Observation Apical maize florets differentiate later than basal florets.
- Observation Apical maize kernels have lower dry matter accumulation rates than basal kernels.
- Observation In unheated ears, apical kernel endosperm had lower sucrose concentration than basal kernel endosperm.
- Observation In unheated ears, apical kernel endosperm had lower ADP-Glc starch synthase activity than basal kernel endosperm.
- Observation In unheated ears, apical and basal kernel endosperm had similar ADPG-PPase activities.
- Intervention effect With tip heating, apical kernel endosperm had the same growth rate and final weight as basal kernel endosperm.
- Intervention effect Tip heated apical kernels had higher sucrose concentrations.
- Intervention effect Tip heated apical kernels had higher ADP-Glc starch synthase activity.
- Intervention effect Tip heated apical kernels had similar ADPG-PPase activity.
- Intervention effect Tip heating did not increase total grain weight per ear.
- Intervention effect Tip heating increased the size of apical kernels.
- Intervention effect Tip heating slightly decreased the size of basal and middle position kernels.
- Intervention effect Tip heating hastened some developmental events in apical kernels.
- Intervention effect ADPG-PPase activity reached peak levels earlier in tip heated apical kernels.
- Intervention effect ADP-Glc starch synthase activity reached peak levels earlier in tip heated apical kernels.
- Intervention effect Starch concentration began rising earlier in tip heated apical kernels.
- Intervention effect Tip heating did not shorten the period of starch accumulation in apical kernels.
- Mechanism The authors conclude that pre-pollination floret development alone does not determine the slower growth and smaller size of apical kernels.