The anatomical structure of the tomato (Lycopersicon esculentum Mill.) pericarp was studied in the fruits of five determinant field cultivars. The fruits of the examined cultivars differed in their mechanical properties. Fruits of cultivars which are firm and resistant to injury (Kecskemeti 886j-2, Campbell 28), moderately firm and resistant (Atma, Wenus) and soft, susceptible to injury (line No 155/84) were examined. The pericarp of the cultivars which have fruits resistant to injury had an approx. 200 µm thick covering layer (epidermis plus cuticle plus hypodermis) whereas that of fruits susceptible to injury was only 100 µm thick. In the fruits resistant to injury the cuticle penetrated deeply into the hypodermis, the epidermal cells were flattened and the hypodermis was composed of 4 - 5 rows of cells. The tomato fruits resistant to injury had a thick cuticle layer on their tangential walls — whereas those more susceptible had a thick cuticle layer on these walls.
In recent years, the demand of chilli has tremendously increased due to its attractive market price and multifarious used in cooked and processed forms. At present people are much concerned about the fruit quality and yield. Therefore, attention is being paid for development of genotypes having high yield potential with desirable fruit quality characters in a short period of time. For this purpose, seeds of chilli were mutagenised with ethyl methane sulphonate (EMS) and diethyl sulphate (DES) to determine their mutagenic sensitivity in M1 generation. The increasing concentration of EMS and DES decreased in morphological and yield characters. The spectrum of mutation and induced variability for various quantitative traits were observed in M1 generation such as germination (%), plant height, primary and secondary branches per plant, days to first flowering, fruit length (cm), fruit girth (cm), total number of fruits per plant, number of seeds per fruit, seed weight per fruit (g), 100 seed weight (g) and pericarp: seed ratio showed variability in chilli with the effect of EMS and DES. The percentage of chromosomal abnormalities in different mitotic stages was significantly higher than that of the control in all the treatment concentrations.
Achene macro- and micromorphology and pericarp anatomy are described in four Polish species of Anemone (A. narcissiflora, A. nemorosa, A. ranunculoides, A. sylvestris). Biometric analysis showed that achene size varies greatly in all the studied species and is of limited diagnostic value. Three types of sculpture connected with the character of the indumentum were distinguished. The presence or absence of stomata on the achene style and the character of the hair base differentiated A. nemorosa and A. ranunculoides, which have the same type of pericarp ornamentation. The endocarp (number of layers and outline of its cells) was shown to be useful in the systematics of Anemone.
The development of the pericarp and its taxonomic value were studied in Potamogeton lucens, P. pusillus, P. crispus, P. pectinatus. The fruitlet of Potamogeton is drupaceous. Anatomical study and image analysis of developmental stages in the pericarps confirmed differences between species. The different degrees of pericarp sclerification, different positions of lignified cells in the pericarp, and numbers and types of pericarp layers have great diagnostic value. The vascular system of the Potamogeton flower and fruitlet, and the centrifugal direction of pericarp sclerification, do not have taxonomic significance within the genus Potamogeton. There are no significant differences in cell and layer size in Potamogeton fruitlets between the four species studied.
The research material used to evaluate the relationship between technological features of soft-flesh fruit involved the lines derived from the interspecific hybrid Capsicum frutescens L. x C. annuum L. The genotypes differed in their yielding, morphological features of fruit, technological efficiency and the content of capsaicinoids, which ranged from 20 to 770 and from 10 to 330 mg.kg-1, respectively, of capsaicin and dihydrocapsaicin in the pericarp, from 60 to 3870 and from 30 to 1550 mg.kg-1 in the puree produced as a result of mechanical separation of the soft tissue of the pericarp from the inedible parts (placenta, seeds, septa and the peel). There was found a negative correlation between the fruit average weight and length and the content of capsaicin in the pericarp and in the puree and for the capsaicinoids sum in the puree. The contents of the two compounds were positively correlated in each material researched, both when individual capsaicinoids were compared and when their sum was given.
The studies aimed at determining the levels and reciprocal proportions of capsaicinoids (capsaicin and dihydrocapsaicin) in the pericarp and puree obtained by the mechanical separation of the soft tissue from the inedible parts of fruits. The studied material involved a few lines, selected from the interspecies hybrid of Capsicum frutescens L. x C. annuum L., manifesting a soft-flesh tissue of pericarp in mature fruits. The quantitative estimation of capsaicinoids was conducted using HPLC. The capsaicin content in the studied lines ranged from 9 to 27 and from 20 to 387 mg. kg-1 in the pericarp and puree, respectively. For dihydrocapsaicin, the values ranged from 3 to 26 and from 6 to 155 mg. kg -1, respectively. Depending on the genotype group, the content of each of the compounds in the puree was 2.5- to about 10-fold higher than in the pericarp tissue. Both in the pericarp and in the puree the level of capsaicin was around 2.5-fold higher than that of dihydrocapsaicin.
Results of anatomical studies on the developing pericarp of selected wild roses are presented. Using SEM and CLSM, the changes in the pericarp structure of 5 species have been observed during its formation, from the flowering stage to fully ripe achenes. In the morphological development of the pericarp of Rosa species two main phases can be distinguished: the phase of intensive growth of the pericarp during which the fruit achieves its final shape and volume, and the subsequent phase of pericarp ripening when no significant morphological changes in the pericarp occur. Similarly, in the process of the anatomical development of the pericarp two phases are noticeable, however, during both stages, great internal changes proceed in the fruit. The first phase consists of intensive cell divisions and enlargement, gradual thickening of cell walls and formation of all pericarp layers. Due to these changes, the pericarp achieves its final anatomical structure. The second phase, involving the pericarp ripening, is manifested in the modification of cell walls, mainly by their quick thickening, but first of all by their lignification. The lignification of pericarp cell walls begins in the inner endocarp; it proceeds in the outer endocarp, later in mesocarp and finishes in the hypodermal cells of the exocarp. The epidermal cells remain alive the longest and their walls do not (or hardly) become lignified. The death of all cells finishes the pericarp ripening.
The establishment of certain morphological, physical and physiological criteria was considered and this might allow us to determine more precisely the maturation degree as well as the optimum harvest and sowing period of seeds. The criteria for assessing the maturation degree of seeds presented earlier (the completely formed embryo, the prominent endosperm with a normal consistency) can now be completed with a new criterion, namely the one referring to the slight tendency of the seesds tegument to get yellow. This is due to the fact that the seed completes its growing sooner than the pericarp. The fact was proved both by the greater decrease the fresh mass of the pericarp than that of the seed and by the greater decrease of the moisture content of the seed than that of the pericarp during the four examined ripening phases.