著者
Taku Yano Akiyoshi Morisaki Shun-ichiro Ito Masaharu Kitano
出版者
The Japanese Society for Horticultural Science
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.OKD-112, (Released:2018-07-21)
被引用文献数
2

To predict the seasonal vegetative growth of potted seedlings of Satsuma mandarin, the effects of initial plant conditions (age, shoot pruning), environment (greenhouse, greenhouse + shading, open-field culture), and pot size on growth were researched for 1.5–2.5 years. The growth pattern was evaluated using a curve fitting with the 4-parameter logistic (4L) model, biomass allocation, and classical (interval) growth analysis, and a generalized linear model analysis based on thermal time (tt). Growth delays from shoot pruning were confirmed by growth trajectories with the 4L model based on tt. Plant growth was positively affected by enlarging the pot size (from 20-L to 45-L), while shading significantly suppressed the growth of 45-L potted Satsuma mandarin seedlings in the greenhouse. In the growth analysis, the relative growth rate was not always determined by the net assimilation rate (NAR), which included both shoot-pruning and pot size effects. To predict the plant mass of Satsuma mandarin seedlings (MP), we proposed several generalized linear models using a log link function assuming that MP followed a Gamma-distribution. The best model to predict MP was selected based on Akaike information criterion (AIC) values, and contained explanatory variables for initial plant biomass, NAR, specific leaf area (SLA), leaf mass ratio (LMR), pot size, and tt. Some simpler models excluding NAR, but including SLA and/or LMR as explanatory variables, were more useful than a model lacking growth analysis parameters (NAR, SLA, and LMR).
著者
Taku Yano Akiyoshi Morisaki Kimiaki Matsubara Shun-ichiro Ito Masaharu Kitano
出版者
一般社団法人 園芸学会
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.OKD-051, (Released:2017-07-21)
被引用文献数
4

To establish cultural practice based on a consecutive growth model for potted 1-year-old seedlings of Satsuma mandarin (Citrus unshiu Marc.), growth analysis by classical and functional approaches was conducted under different light conditions and air temperatures over 2.5 years, and the active growth of potted seedlings in the greenhouse was investigated. Under the classical approach, the general change patterns of relative growth rate (RGR) and net assimilation rate (NAR) were hard to determine because of irregularities including quiescence of vegetative growth. Under the functional approach, plant mass modeled using linear, exponential, power-law, monomolecular, three-parameter logistic, four-parameter logistic (4L), and Gompertz functions showed significant correlations with the observed plant mass. 4L was the best model because it showed the highest r, and the lowest root mean square error and Akaike Information Criterion, so RGR and NAR were estimated by 4L. Analysis of the RGR components showed significant positive correlations between RGR and NAR. Analysis of covariance indicated the NAR costs for increasing RGR were lower in the greenhouse than in open culture; this was explained by differences in specific leaf area (SLA). Therefore, in greenhouse culture, growth was primarily enhanced by NAR as net photosynthesis and underpinned by SLA as a morphological trait improvement for the relatively low light intensity compared with open culture. A multiple regression model for NAR using the pooled data (n = 60) suggested solar radiation had a positive effect (P < 0.0001) and air temperature had a negative effect (P < 0.01) on NAR.