On-site variety discrimination of tomato plant using visible-near infrared reflectance spectroscopy

The use of visible-near infrared (NIR) spectroscopy was explored as a tool to discriminate two new tomato plant varieties in China (Zheza205 and Zheza207). In this study, 82 top-canopy leaves of Zheza205 and 86 top-canopy leaves of Zheza207 were measured in visible-NIR reflectance mode. Discriminant models were developed using principal component analysis (PCA), discriminant analysis (DA), and discriminant partial least squares (DPLS) regression methods. After outliers detection, the samples were randomly split into two sets, one used as a calibration set (n=82) and the remaining samples as a validation set (n=82). When predicting the variety of the samples in validation set, the classification correctness of the DPLS model after optimizing spectral pretreatment was up to 93%. The DPLS model with raw spectra after multiplicative scatter cor- rection and Savitzky-Golay filter smoothing pretreatments had the best satisfactory calibration and prediction abilities (correlation coefficient of calibration (Rc)=0.920, root mean square errors of calibration=0.196, and root mean square errors of predic- tion=0.216). The results show that visible-NIR spectroscopy might be a suitable alternative tool to discriminate tomato plant varieties on-site.

Effect of Exogenous Lanthanum on Accumulation of Cadmium and Its Chemical Form in Tomatoes

In the condition that soil is polluted by Cd（20 mg·L-1）,two varieties of tomato（Lycopersicon esculintum Mill.）（plant high Cd-enriched variety（Yufen109）and plant low Cd-enriched variety（4641））treated with LaCl3 of different concentration（0,10 and 20mg·L-1）were determined for their effect on plant dry weight,anti-oxidase activity（CAT,SOD and POD）,tomato fruit Cd chemical form and Cd accumulation.The results show that 10 mg？L-1LaCl3 can increase dry weight of plant at various positions and can reduce the concentration of Cd of different forms.Spraying with LaCl3（10,20 mg·L-1）can reduce Cd concentration in leaves,stems,roots and fruits of tomato plants with lowering rates of 13.7%-31.9%,9.5%-30.6%,10.8%-44.5%and 19.4%-37.0%,respectively.Suitable amount of lanthanum（10 mg·L-1 LaCl3）can increase yield of tomatoes,reduce Cd accumulation in the fruit.In the two tomato varieties,Lanthanum and Cadmium react interactively,expressing to be coexisting of both synergism and antagonistic.