Felipe Koch

Qualidade fisiológica de sementes de feijão tratadas com zinco

O trabalho teve como objetivo avaliar o efeito de doses de zinco aplicado em tratamento de sementes sobre a qualidade fisiologica de sementes de feijao e o teor foliar de micronutrientes. O trabalho foi desenvolvido na safra agricola 2014/2015, no laboratorio didatico de analise de sementes, no laboratorio de fertilidade e em area experimental, da Faculdade de Agronomia Eliseu Maciel, da Universidade Federal de Pelotas. Para a realizacao do experimento foi utilizado sementes de feijao cultivar BRS Expedito. Os tratamentos foram constituidos pelas seguintes doses aplicados via sementes com produto a base de Zn, nas doses de 0 (0g Zn), 100 (12,0 g Zn), 200 (24,0g Zn), 300 (36,00g Zn), e 400 (48,00g Zn) mL P.C.100kg -1 de sementes. Foram realizadas avaliacoes na emergencia, indice de velocidade de emergencia, teste de frio, comprimento de parte aerea e radicular, massa seca de parte aerea e radicular de plântulas e determinacao dos teores de micronutrientes. O tratamento de sementes com zinco promove aumento na expressao da qualidade fisiologica de sementes de feijao e tambem aumento no teor foliar do micronutriente.

Ecology of Upland Rice Plants and Seeds Subjected to Growth Regulator

The objective of this work is to verify the influence of the plant regulator trinexapac-ethyl on plant growth and physiological quality of upland rice seeds. We used an upland rice genotype, and the growth regulator was the trinexapac-ethyl. The experiment was completely randomized in a 4 × 8 factorial design related to four concentrations of the plant regulator trinexapac-ethyl [0 (without growth regulator), 0.25, 0.50, and 0.75 L c.p. ha-1] and 7 plant collection times [14, 28, 42, 56, 70, 84, 98 days after emergence (DAE)], with four replicates. To determine growth attributes, we evaluated total dry matter, dry matter production rate, relative growth rate, leaf area ratio, leaf matter, leaf area index, solar energy conversion efficiency and partition of assimilates. The physiological quality of the seeds was evaluated based on germination, first germination count, field emergence, emergence speed index and seedling dry matter. Plant growth was affected by the growth regulator. Total dry matter, dry matter production rate and solar energy conversion efficiency decreased, while leaf area index, leaf area ratio and leaf matter increased due to the effects of the growth regulator. The dry matter partition of plants changed in plants subjected to the growth regulator, with a delay in the targeting of assimilates to reproductive organs and a greater allocation to roots at the end of the cycle in plants subjected to the doses 0.50 and 0.75 L·ha-1 of growth regulator. Seed vigor was adversely affected by the growth regulator.