Hormonal extracts of cherry tomato fruits (Lycopersicon esculentum Mill.) cv. Small Fry at different stages of fruit development and maturation were bioassayed for their auxin, gibberellin, cytokinin and growth inhibitor activities. In general, the levels of endogenous growth promoters were much higher in the young developing fruits than in the more mature fruits. Free cytokinin levels were highest in the first two weeks of development then declined rapidly. However, cytokinin activity in the ribotide fraction, after treatment with alkaline phosphatase, decreased during thefirst three weeks of development then increased rapidly over the following four weeks. Auxin levels increased during early development to reach a maximum in three‐week‐old fruits after anthesis. Gibberellin levels during the first two weeks of development were much lower than those of auxins and cytokinins, but then increased to reach a peak in the fourth week after anthesis. A growth inhibiting substance with Rf similar to that of abscisic acid was found in the acidic fraction of the fruit extracts. This inhibitor increased gradually during fruit growth and development and reached a peak at the age of five weeks which coincides with the green mature stage.

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SUMMARYExperiments were conducted to study the effect of plant injection with growth regulators on the dormancy of onion bulbs cv. Elba Globe. Application of abscisic acid induced early senescence of the leaves and prolonged the rest period of the bulbs. This effect was partially overcome by subsequent applications of gibberellin, auxin or cytokinin and totally overcome with the application of a mixture of the three hormones. Maleic hydrazide application prolonged the rest period by inhibiting both sprouting and rooting of the bulbs throughout the storage period. This inhibitory effect was not overcome by the subsequent application of auxin, gibberellin, kinetin, or their combinations. Ethephon application increased rooting of bulbs and partially overcame the effect of abscisic acid on dormancy.

Changes in growth, endogenous levels of hormones, ethylene evolution and cellulytic and pectolytic enzyme activities of cherry tomato fruits (Lycopersicon esculentum Mill. cv. Small Fry) were assayed from anthesis through ripening. After anthesis, growth of cherry tomato fruit follows a three‐dimensional and sigmoid growth pattern which consits of cell division, cell enlargement, mature green, pink and red stages. Cytokinins and auxins were abundant and reached their peak during early development (cell division). Gibberellin levels were more prominent during the period of cell enlargement and reached a peak before the green mature stage. Levels of abscisic acid increased gradually during maturation and reached a maximum in the advanced green mature stage. Respiration pattern was characterized by a climacteric peak at the pink stage. Ethylene production remained less than 2 μl/kg fresh weight an hour until shortly before mature green stage, then rose rapidly to a maximum at pink stage. Activities of cellulytic and pectolytic enzymes were first detected at the green mature stage and increased rapidly during fruit ripening.

Genetics of flower Color in winka Catharanthus roseus (L) G.Don were investigate by inheritance two types(strains) of plants with different flowers color were used in this study, violet (V) and White (W) color as parents, to determine the number of genes involved. This study was conducted at the Department of Chemistry &Biology at the Faculty of Education, University of Kassala, kassala State, Sudan, during: the autumn, seasons for two years 2010-2012. First the two parents were covered to ensure self pollination. Reciprocal cross has been carried out between the two inbred parents. The study showed that a single pair of genes is probably involved in flower colour and that gene for violet color is incompletely dominant over that for white color. The reciprocal crosses gave the same results indicating no role of cytoplasmic genes in the inheritance of these colors.