The effect of low P on stele (TSA) and xylem vessel (MXA) areas depended on the genotype and followed similar patterns as RXSA since these traits were correlated (for RXSA vs. TSA, r = 0.83, for TSA vs. MXA, r = 0.56), as previously reported (Kondo et al. 2000; Uga et al. 2008).
Since there were 63 patients with ePTH at 6 months and using the rule of thumb of 10 events per covariate, the 5 most statistically significant covariates (based on lowest P values) in the univariate analysis were entered into multivariable analysis.
However, genetic variation for the effect of low P on these traits has not been investigated.
There was no significant effect of low P on MXV and no significant genotype x P interaction.
The effects of low P on TSA varied from more than 33%% reduction in IR64 to more than 44%% increase in Azucena (Fig. 6).
Therefore, we selected 15 cm from the root tip as the sampling position for investigating the effects of low P on RCA and other root anatomical traits.
Although there was no significant overall genotype x P interaction, the effects of low P on %AA varied from no effect in IR64 and Basmati to an approximately 40%% increase in Azucena, Pokkali and Leung Pratew (Fig. 7).
Genotypes varied in the extent and sometimes the direction of their responses to low P, depending on the trait.
Superdosing reduced feed conversion rate (FCR) at all P levels (P < 0.05), although this effect was more pronounced on the low P diet, suggesting that sufficient P being released from the phytase itself to re-phosphorylate MYO and hence improve FCR.
On the high soil P site, A. senegal had significantly lower foliar (15N levels than neighboring non-leguminous species (Balanites aegyptiaca), while foliar δ15N values in A. senegal on the low P site exhibited no significant difference with our reference plant, B. aegyptiaca.
