## 3 Discussion
Temporal Effects of Bacterial Inoculation Show Accelerated Growth Rates at the Early Stage of Plant Growth Depending on Root Type and Temperature Condition  
Although the growth stimulation imparted by the bacteria was a prominent trend, the difference between the inoculated and the control ones varied at different stages of the plants' development--initially increasing and then decreasing at certain timepoints. Under the ambient condition, the effect of the bacterial inoculation on the root lengths and growth rates showed early in the root development, and the stimulation effect increased up to a certain timepoint depending on the root type (Figure 2b-d,g-i). For example, the stimulation on the primary roots increased up until 9 DAI and until 12 DAI for the 1 storder lateral roots, while the 2 nd-order laterals showed continuous growth and bacterial stimulation until 21 DAI. After these time points (except for the 2 nd lateral roots), the stimulation effect declined although there were still significant differences between the inoculated and non-inoculated plants. This outcome, in part, corroborates the result that was found by [PERSON] et al. 2013 [46]. They found that drastic changes occurred, including accelerated plant growth in Arabidopsis in their inoculation study at 13 days after sowing them. However, although the strain PsJN accelerated the growth rate during the first half of the plants' development, the growth rates then levelled off and the plant size converged with that of the non-inoculated plants. In our study, it may be as well that if the plants were allowed to grow further, a similar outcome might have taken place. For the shoots, their study demonstrated that the larger rosette areas of the PsJN-inoculated plants during the first half of their life cycles are correlated with the larger leaf areas, rather than there being an increase in the number of leaves. This illustrated that the bacteria PsJN acted as PGPR by accelerating the growth rates, and thus producing bigger plants [46]. The accelerated growth in the early stages of the inoculated plants, which can be attributed to the various mechanistic effects of the bacteria, may provide beneficial effects to the plants including improved nutrient acquisition and/or a direct effect on the plant metabolism [46]. On the other hand, based on the living theory that longevity is negatively correlated with the metabolic rate [95], the rapid growth that occurred during the early stages of life may be associated with a reduced longevity and an impaired future performance [96]. This may be the case with heat-stressed plants, where the accelerated growth rates, particularly during the early growth stage, are generally followed by an earlier reproductive and flowering stage. The GrowScreen-Agar II Is an Efficient Platform for Plant Cultivation, Non-Invasive Phenotyping, and Root and Shoot Trait Characterization  
The GrowScreen-Agar II platform provided an efficient growing system that enabled a more natural growth to take place for the Arabidopsis roots and shoots as compared to the conventional \"closed-plate\" setup. The previous version of this platform was compared to the already existing phenotyping setups in [52]. Notably, the strategic design of the agar plates allowed the unobstructed, open-air growth of the shoots which still is a distinguishing feature, also, in the newer systems. This is also a trait in another recent platform GLO-Roots [97; 98] which has a similar \"open-top\" approach, while the MultipleXLab [99] one sticks to the conventional \"closed-plate\" system. Having access to the leaves opens the potential for the non-invasive monitoring of the plant's physiological parameters such as chlorophyll fluorescence and gas exchange, i.e., net photosynthetic rate, stomatal conductance, and transpiration, which are important indicators of the plant's response to the climate and environmental changes (e.g., [4; 100; 101]).