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Appreciation of ethrel on ripening dynamic and on the content of ingredients in processing tomato (Lycopersicon lycopersicum (L.) Karsten) varieties
33-35.Views:134Tomato (Lycopersicon lycopersicum (L) Karsten) is an important crop cultivated in Hungary. Ethrel has been used to advance maturity and promote uniform ripening of processing tomato since 25-30 years in Hungary. The aims of the present study were 1) to evaluate the effects of two different ethrel concentrations on ripening rate, 2) to investigate lycopene content of different maturity stages, 3) to test the effect of ethrel on lycopene content. It is important to note that the experimental year (in July and August) was very rainy and cool. Ethrel was applied at two rates: 1500 and 3000 ppm. The results clearly indicate that Ethrel can be a useful and effective tool of maturity-enhancement, under present circumstances. Ripening concentration increased significantly by Ethrel. In spite of this, Ethrel treatments did not affect lycopene content of examined varieties significantly. The quality of tomato products are characterised by their lycopene content. Colour is highly important quality factor of food products. The range in lycopene contents from all samples evaluated was 48.7 to 113.0 mg kg-1 fresh weight. Also correlations between lycopene content and colour (a*/b*, and chroma) were investigated also.
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Effect of seedling quality on growth, yield and quality of tomato (Solanum lycopersicum L.)
64-72.Views:213A two trial greenhouse experiment was carried out at Rwanda-Israel Horticulture Centre of Excellence located at Mulindi Station to evaluate seedling quality on growth, yield and quality of tomato. The seedlings were grown in different growing media and produced seedlings with varying quality indices. The growing media of peat moss 100% (T2) and sand + goat manure + carbonized rice husks 50%: 10%: 40% (T8) were revealed in seedlings with the highest mean quality indices of 31 and 28 respectively, while sand 100% (T2) presented the lowest quality indices during both trials. The transplants were planted in polybags filled with 2:1 of topsoil and kitchen manure arranged in a randomized complete block design (RCBD) with four replications. Collected data were subjected to analysis of variance and means were separated using HSD test at a 5% level of significance. The results revealed that the seedlings grown in T1 (S1) and T8 (S8) consistently presented tomatoes with better growth performance and yield. S1 and S8 produced mean yield of 93.59 and 92.35 t/ha respectively while S2 had the lowest yield with 53.86 t/ha. The fruit produced from seedlings grown in T4 (S4) had the highest mean sugar acid ratio of 5.88 but not significantly different from 5.61 and 5.44 of S1 and S8 respectively. Hence, there was a positive relationship among seedling quality and growth and yield performance of tomato but not in fruit quality.
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Effect of maturity stage on content, color and quality of tomato (Lycopersicon lycopersicum (L.) Karsten) fruit
41-44.Views:456Soluble solids (Brix°), carbohydrate, organic acid, lycopene, polyphenols and HMF content of indeterminate round type tomato Lemance F1 fruits were measured in six ripeness stages from mature green to deep red stage. Color of fruits was determined by CIELab system. The L*, a*, b* values were received directly and used to calculate from which the a*/b* and the chroma were calculated. The Brix', carbohydrate, lycopene and HMF content were the highest in the 6111 stake (deep red). Carbohydrate contents constitute nearly 50% of the Brix°. The mature green stage had the lowest acid content but in subsequent stages it was fundamentally unchanged. Polyphenol content changed little during fruit ripening. Lycopene content changed significantly during maturation and accumulated mainly in the deep red stage. Analyses showed that a*/b* was closely correlated with lycopene and can be used to characterize stages of maturity in fresh tomatoes.
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Relationship between flowering, fruit setting and environmental factors on consecutive clusters in greenhouse tomato (Lycopersicon lycopersicum (L) Karsten)
111-116.Views:125The main season of greenhouse tomato begins late winter or early spring in the northern Temperate Zone. During this period decisive environmental factors affect flowering and fruit setting.
In the present experiments, progress and dynamics of greenhouse tomato flowering and fruit set were examined in 1999 and 2001 spring. The beginning and the end of flowering and fruit set, the number of flowers and fruits set in each cluster were recorded. Flowering and fruit set characteristics were analysed with respect to the accumulated PAR and temperature were calculated for each cluster. One flower required 31.3 mol M-2 of accumulated PAR and 38 °C of sum temperature as an average for anthesis. One fruit required 27.9 mol m-2 of accumulated PAR and 33.3 °C of sum temperature as an average for fruit setting.
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General defense system in the plant kingdom III.
45-54.Views:153Our observations regarding the symptoms not fitting into, significantly differing from the hypersensitive defense system, which we noticed during the judgment of several plant species, symptoms provoked on several million plants have constituted a unified entity. They have provided evidence for the existence of a different plant defense system. We called this so far unknown basic response of plants to biotic effects as general defense system. This system defends them from the attack of numerous microbe species in the environment.
The evolutionary intermediate phase between the general and the specific, the two defense systems is the susceptible host—pathogen relation. The vertical resistance system of plants escaping from the susceptible host—pathogen relation, based on specific hypersensitive reaction also suggested the existence of a more original, general defense system and the susceptible host—pathogen relation developed as a result of the collapse of that system.
The evolutionary relation of the two defense systems is proved by the only recessive inheritance of the older general defense system and in the majority of cases dominant hereditary course of the specific defense system. In our experiences, the modifying genes of the recessive general defense system, in most cases, are behind the specific defense systems, which are known to have monogenic dominant hereditary course and react with hypersensitive tissue destruction. This seemingly striking genetic fact is explained by the following: the general defense system less dependent on environmental effects regulates much faster pathophysiological reaction than the specific resistance genes strongly dependant on environmental effects coding dominant hypersensitive reaction.
The general and specific defense reactions, the processes excluding the microbes attacking plants with compacting of cell growth and tissue destruction, which mean two opposite strategies, building on and regulating each other constitute the entity of resistance to plant disease.