TITLE:
Ecology of Upland Rice Plants and Seeds Subjected to Growth Regulator
AUTHORS:
Felipe Koch, Manoela Andrade Monteiro, João Roberto Pimentel, Cristian Troyjack, Ítala Thaísa Padilha Dubal, Eduardo Gonçalves Borges, Vinícius Jardel Szareski, Gustavo Henrique Demari, Lanes Beatriz Acosta Jaques, Ivan Ricardo Carvalho, Francisco Amaral Villela, Tiago Pedó, Tiago Zanatta Aumonde
KEYWORDS:
Oryza sativa L., Trinexapac-Ethyl, Leaf Area, Dry Matter, Seed Vigor
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.9 No.1,
January
16,
2018
ABSTRACT: 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.