Desempenho de genótipos de canola submetidos a diferentes épocas de semeadura em três anos de cultivo

Abstract

The potential for grain yield, defined by genotype-environment interaction can be maximized through the appropriate choice of sowing time. The objective of this study was to evaluate the best sowing date of two canola genotypes in three consecutive years of growing in a wetland located in Slough Paraiba. The experiment was conducted in Areia - PB, in the years 2008 to 2010. The experiment was divided into sub-plots, the main plots nine sowing dates and sub-plots two different genotypes of canola. Were evaluated for agronomic parameters: the initial stand, onset and duration of flowering, emergence to harvest, weight of 1000 seeds and yield. The results showed a significant effect of sowing dates, genotypes, years and time-genotype interaction on-year crop productivity, and obtained satisfactory growth between periods of 07/04 and 02/07 in the three years of cultivation, suggesting that this period occurs in Areia climatic conditions favorable for the development of culture, promoting higher yield than those found in the major canola producing centers in Brazil. Still making a more secure for planting canola, best indicated is between 21 May to 02 July. Outside this period established, the risk of loss is high given the rise in temperature and decrease in water availability in the soil and can not get up to get success in germination time in 9 (05/09). In atypical years with drastic decrease in precipitation sowing should be delayed. To study the conditions of short-cycle genotypes are more recommended than genotypes long cycle, since the risks of long periods of drought is always high, especially from the month of July.