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Flowering is a concatenation of physiological complex processes in which various factors take place. The objective of the present work was to define the influence of the environment-genotypes interaction on the flowering of sugar cane, for its use in the genetic improvement of crops. 80 varieties were used for this purpose, which were planted in three representative areas of the Central region of Cuba (Guayos, Buenos Aires and Mayarí), and some flowering variables, interesting for the improvement of the crop, were studied (intensity, date and masculine fertility) during 12 years (from 1996 to 2007). Years were grouped for its similitude of bloomed varieties just like genotypes, the CLUSTER analysis was used in all cases. An ANOVA factorial (genotype, locality and year) was applied to all genotypes that bloomed at last one year in the three localities, in order to define the environment-genotype interaction of the flowering variables. In cases in which interaction occurred it was represented using the method of main additive effects and multiplicative interactions (AMMI). As a result, we found that locality was the main source of variation, the one that had the highest influence in the majority of flowering variable in the studied area. In this work we discuss interactions that are useful for its handling in the Genetic Improvement of crops. [ABSTRACT FROM AUTHOR]

The poor flowering and the differences in the date of exit of the flower in commercial varieties of sugar cane at Guayos's locality make hard the realization of crossbreedings, which is why objective of this work is to propose a strategy that it enable to increase them. Several experiments, that they executed themselves in areas of the seat of the National Center of Hybridization, located in Guayos got on for it and included two dates of plantation, two dose of fertilizers, two methods of sheets, use of irrigation and Ethrel in the inductive stage and Fitomás-E, in the stage after inductive of the flower. You used a control with the methodology in use of handling of the flower for this locality for all of the cases, and they measured the bloomed varieties, intensity of flowering and date or days to start of flowering, the one with which an analysis of variance was used and when it was significant the stockings through Tukey's proof compared . As a result it was found that flowering increased in with use irrigation, than the Fitomás-E you advanced the date of exit of the flower, in the meantime than July's and January's plantations, the cut of sheets, the application of Ethrel and of fertilizers, you delay it. These combined results can be used to enlarge the time of flowering and served as base stops a strategy that it enables proposes the quantity of crossbreedings at Guayos's locality increasing. [ABSTRACT FROM AUTHOR]

The frequency of occurrence of the atypical dry or rainy periods during the last years as a consequence of the global warming, it has put up to the establishment of a new conception for the evaluation and handling of the varieties of sugarcane of sugar (variety families). Under those new premises, 48 experiments in at random Blocks were designed and established, in four contrasting regions of the country. They were harvested during the whole year, with combinations of ages between 9 and 24 months. The variables t cane/ha, pol % in cane and t pol/ha were studied to determine if the studies of locations were necessary for the environment classification. Resulting that the Discriminant Analyses allowed to group the ages and the crop moments in each stump, with acceptable values (higher than 73%) of good classification, while the main components analysis offered the necessity to continue studying the cultivars in the four evaluated locations. [ABSTRACT FROM AUTHOR]

Harvesting of sugarcane at a proper time, by adopting right techniques, is necessary to make better use of the available genetic material. By determining the harvesting time period for each sugarcane variety to show its highest potential, both yield and sugar quality, higher levels of profitability are achieved. The aim of this study is to identify the harvest time of sugarcane cultivars, as well as the stability of the cultivars studied in five localities. The study was conducted at the Sugarcane Research Stations in Villa Clara, Sancti Spiritus, Camagüey, Holguin and Santiago de Cuba. Five experiments were planted (one for each locality), in a randomized complete block design with three replications under rainfed agriculture. Two harvest times were established, time 1 (M1), according to the harvest data from November to January (beginning of harvest), and time 2 (M2) taking into account the data collected from February to April (average stage- end of harvest). The discriminant analysis results allowed establishing two harvest times (November to January and February to April) in these five localities, where the effectiveness of each cultivar-Iocality-harvest time combination was higher than 74%. In general, it is advisable the use of cultivars C86-12 and C92-514 during M1 in these five localities, as well as the use of C90-530 in specific zones; and the use of cultivars C92-514 and C89-165 during M2. [ABSTRACT FROM AUTHOR]

The main breeding programs in the world have heeded sugarcane classification of test environments, so that the evaluation of genotypes across different environments is one of the most common practices for the recommendation of new cultivars to producers and as its stability. This study aimed to evaluate agroproductivamente varieties of sugar cane plantation plots cold, resistant to adverse conditions of water deficit and its stability in various environments. Under these new assumptions developed in this study Territorial Research Station of Sugarcane Villa Clara in the cold cycle, in a randomized complete block, the variables were percentage of pol in cane, tons of cane per hectare pol tons per hectare. The result was that the genotype C86-156 high agricultural yields and stable in all environments and high sugar content, so their harvest should be in the initial stage of harvest (December-January), and C89-147 which is the highest performance, but not stable environments. Identifies five test environments with specific genotypes, where November is characterized by C90-530 and C89-147, December by C86-56 January for C89-148, C86-156 by February and March by C85-102. [ABSTRACT FROM AUTHOR]