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Effect of maturity stage on content, color and quality of tomato (Lycopersicon lycopersicum (L.) Karsten) fruit
41-44.Views:480Soluble 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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General defense system in the plant kingdom III.
45-54.Views:168Our 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.
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Detergent induced pollen sterility in some vegetable crops
85-88.Views:141Efficacy of a popular synthetic detergent, Surf excel in some important vegetable crops viz. Okra or lady finger (Abelmoschus esculentus L.), chilli or red pepper (Capsicum annuum L.) and tomato (Lycopersicon esculentum Mill) was evaluated for inducing male sterility and hybrid seed production. Foliar sprays with aqueous solutions of Surf excel (1.0 and 1.5% w/v) in these crops induced complete pollen sterility. The treated plants showed a delay in flowering, a reduction in the number of flowers and fruits/plant, number of seeds/fruit resulting in a reduction in yield/plant. However, the male sterility thus induced was successfully exploited for hybrid seed production.
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Studies on the Tobamovirus resistance of the pepper (Capsicum annuum L.) cultivar Greygo
71-75.Views:155Resistance of the Hungarian pepper (Capsicum annuum L.) cultivar "Gre.ygo" to Tohamoviruses has been investigated. All plants of the population of Greygo proved to be resistant to tobacco mosaic and tomato mosaic viruses (TMV, ToMV), both represent the pepper pathotypes Po of Tohamoviruses. Individuals of Greygo, however, were found to be susceptible to pathotypes P12 and P123 of pepper mild mottle virus (PMMV). When inoculated with the XM isolate of dulcamara yellow fleck virus (DYFV, pathotype P1) the population of Greygo segregated in resistant and susceptible plants. These results as well as inoculations of the progenies of three TMV resistant plants clearly showed, that besides the resistance allele Li the cultivar Greygo possesses also an another allele. This allele, provisionally marked by L2g behaves like to the allele L2 characteristic to Capsicum frutescens cv. . Tabasco. Determination of the identity of the allele L2g to the allele L2 needs further genetic and pathological informations. Relations between the Tohamoviruses pathogenic to pepper and the alleles of the resistance gene L are outlined for the discussion.
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Study on the viruses of Petunia in Hungary
55-59.Views:133Virus susceptibility of 11 varieties of vegetatively propagated petunia against 2 virus strains (TMV-C/U1 and PVYNTN) were examined. Neither resistant nor tolerant varieties of petunia were found. The virus infection of the Petunia genus was examined in Hungary. The most common pathogens were the Tobacco mosaic tobamovirus (TMV) and the Tomato mosaic tobamovirus (ToMV), but the samples also contained Alfalfa mosaic alfamovirus (AMV), Cucumber mosaic ClIC11171014171S (CMV) and Potato Y potyvirus (PVY). Potato X potexvirus (PVX) was isolated in the varieties of trailing petunia for the first time.