Acessibilidade / Reportar erro

Wheat breeding: X. Heritability estimates and associations of tolerance to aluminum toxicity and grain yield with other agronomic characteristics in wheat

High grain yield potential, and Al sensitive cultivar Alondra S-46 was crossed with standard height, low grain yield potential, Al tolerant cultivars IAC-5, BH-1146 and C-3. Parents, F1's, F2's and reciprocal backcrosses were tested for their seedling reaction to 6 ppm of Al3+ in nutrient solution. Grain yield, plant height, number of spikes per plant, number of spikelets per spike, number of grains per spike, number of grains per spikelet, 100-grain-weight and spike length were determined for the same populations at maturity. Narrow sense heritability estimates were high for spike length, number of grains per spike, 100-grain-weight, and plant height; moderate for number of spikes per plant and number of spikelets per spike; and low for the rest of the agronomic characteristics under study. Additive effects were the main source of genetic variation for spike length, plant height, number of grains per spike and 100-grain-weight. Grain yield of the studied populations was significantly correlated with all the agronomic characteristics under study except the number of spikelets per spike. Tolerance to Al3+ toxicity was not associated with plant height (except for the population from the cross Alondra S-46 x IAC-5), grain yield and number of grains per spikelet (spike fertility). The results suggested that there is a possibility of selecting plant types that combine Al3+ tolerance, semi-dwarf height levels and high yield potential, to be grown on acid soils


Instituto Agronômico de Campinas Avenida Barão de Itapura, 1481, 13020-902, Tel.: +55 19 2137-0653, Fax: +55 19 2137-0666 - Campinas - SP - Brazil
E-mail: bragantia@iac.sp.gov.br