Fruit characteristic and flesh tissue feature of special firmness type processing tomato cultivar

Abstract: The object of this paper is to analyze fruit and flesh tissue of special firmness type processing tomato breeding lines. The breeding lines of WT-75 and WT-76 generated via open field were employed in this paper to evaluate the variance of fruit’s main quality traits, such as the content of fruit soluble solid, the content of total acid, the content of lycopene, compression resistance of per fruit, water content for flesh tissue, and the content of soluble pecti. Meanwhile, the characteristic of fruit flesh tissue between different materials using paraffin section and electron microscope technology was also analyzed. The results showed that the firmness of WT-75 and WT-76 gained by hand squeezing was ultra-hard compared to the soft fruit of control ZH-10. The compression resistance of per fruit of WT-75 and WT -76 tested by flat plate compression were 79.70 N and 77.71 N which were significantly (P<0.01) stronger than control ZH-10 level. Moreover, among all the fruit quality traits, the concentration of soluble pectin of WT-75 and WT -76 was significantly (P<0.05) higher than control ZH-10, and the content of soluble pecti of this three lines was 0.66 g/kg, 0.64 g/kg and 0.55 g/kg, respectively. The significant variance did not exist (P>0.05) among other fruit quality traits among different research lines. The results of paraffin section showed that the average fruit flesh cell area of WT-75 and WT-76 was 0.0376 mm2 and 0.0532 mm2 at 200 μm vision which was obviously smaller (P<0.01) and arranged so tightly than control ZH-10 whose average fruit flesh cell area was 0.089 9 mm2. The flesh cell size result from electron microscope observation was similar to the result from paraffin section. Moreover, when the fruits of three research lines stored under room temperature after 35 days, the rotted fruit percent of the control ZH-10, WT-75 and WT-76 was 64%, 93% and 33%, respectively. The degree of rotted fruit of WT-75 was higher than ZH-10 and WT-76. Furthermore, compared to control ZH-10 and WT-76, more lenticels were found on WT-75’s fruit flesh skin from electron microscope observation, which may be the main reason caused the fruits of WT-75 easily rotted under room temperature storage. The research results of main quality of fruit, characteristic of flesh and room temperature storage differences of special firmness type in processing tomato will provide theoretically support for screening the suitable parental lines for hybridization of processing tomato cultivar in the future.