Fruit parthenocarpic

Schijlen EWGM, de Vos CHR, Martens S, Jonker HH, Rosin FM, Molthoff JW, Tikunov YM, Angenent GC, van Tunen AJ, Bovy AG (2007) RNA interference silencing of chalcone synthase, the first step in the flavonoid biosynthesis pathway, leads to parthenocarpic tomato fruits. Plant Physiol 144 1520-1530... 

The pericarp of developing fruit have been shown also to be sites of GA biosynthesis [150-152,158]. Indeed, work with Citrus indicates that the ability of fruit to set parthenocarpically depends on the levels of active GAs produced in the ovary [159]. As discussed above, seeds may stimulate GA biosynthesis in fruit such as pea, that require the presence of fertilised seeds to develop normally [124,150,151]. 

Endogenous auxins are involved in fruit set and growth. Normally, fruit will not develop if the flower is not pollinated and fertilization occurs. In some plants, fertilization of one egg cell is sufficient but in others, such as melons and apples, several seeds must be fertilized. By treating the female flower parts with auxin it is possible to produce parthenocarpic fruit (fruit produced without fertilization) such as seedless tomatoes and cucumbers (30). 

Unless pollination occurs, growth of the ovary usually stops hormones, including GAs, have been detected in the pollen of various species. Moreover parthenocarpic development of the fruit can be induced by treating many species with hormones. 

Seasonal changes in fruit diameter, colour development of the peel (estimated from colour charts) and soluble tannins of persimmon fruits of the cultivars Hiratanenashi (PVA, a parthenocarpic type Fig. 7A) and Jiro (PCNA Fig. 7B) were studied ca.every 10 days at Tsuruoka City in the north of Japan. Soluble tannins in the fruit flesh were measured by the Folin-Denis method. In Tsuruoka, both cultivars usually bloom, starting early in June. 

Fig. 7A,B. Fruits of persimmon. A Hiratanenashi astringent and parthenocarpic. B Jiro nonastringent...

Pandoifini T, Rotino G, Camerini S, Defez R, Spena A (2002) Optimisation of transgene action at the post-transcriptional level high quality parthenocarpic fruits in industrial... 

Soon after the introduction of synthetic auxins it was discovered that they would induce parthenocarpic development of fruits in many species (Table 5.1). 

Table 5.1. Parthenocarpic development of fruit induced by growth substances...

Since the pattern of hormone activity in the developing fruits of seeded and naturally parthenocarpic fruit is similar and only one phytohormone treatment is necessary in the chemically induced parthenocarpic fruits, it seems most probable some phytohormones act as inducing agents starting the filling of metabolic sinks , while others like abscisic and jasmonic acids stop protoplasmic growth (Dathe et al. 1981). Thus the role of plant hormones in fruit development remains obscure. 

Barker WG, Collins WB (1965) Parthenocarpic fruit set in the lowbush blueberry. Proc Am Soc Hortic Sci 87 229-233... 

Garner WW, Allard HA (1923) Further studies in photoperiodism the response of the plant to relative length of day and night. J Agric Res 23 871-920 Gil GF, Martin GC, Griggs WH (1972) Fruit set and development in the pear Extractable endogenous hormones in parthenocarpic and seeded fruits. J Am Soc Hortic Sci... 

Knox RB, Evans LT (1968) Inflorescence initiation in Lolium temulentum L. XII. An autoradiographic study of evocation in the shoot apex. Aust J Biol Sci 21 1083-1094 Kotob MA, Schwabe WW (1971) Induction of parthenocarpic fruit in Cox s orange pippin apples. J Hortic Sci 46 89-93... 

Mainland CM, Eck P (1968) Induced parthenocarpic fruit development in highbush blueberry. Proc Am Soc Hort Sci 92 284-289 Mann LK (1942) Effects of photoperiod on sex expression in Ambrosia trifida. Bot Gaz 103 780-787... 

Siwek, P., Capecka, E. (1995). Yielding fruit quality of some parthenocarpic cucumber cultivars grown under direct cover low tunnel protection. Folia Horticulturae, 11(2), 33-42. 

There are two different types of seedlessness in grapevines, viz parthenocarpy and stenospermocarpy. Parthenocarpy refers to the development of fmit without fertilization. The process produces a sterile fruit that lacks seeds. This means that the pollination results in a production of berries that are completely seedless (Colova-Tsolova et al., 2003). Parthenocarpic seedless berries are mostly small. 

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