Correlation between morphoagronomic traits and resistance to ethylene action in ornamental peppers.

Abstract

The post-production quality of ornamental peppers can be shorted due to exposure to ethylene. The concentration of this phytohormone at 10 µL/L induces leaf, fruit and flowers abscission, ripening of climacteric fruits, organ senescence, seed germination and seedling growth. We evaluated the correlation between pepper morphoagronomic traits and resistance to ethylene on ornamental peppers. Two genotypes, one resistant (UFPB 132), a susceptible (UFPB 134), and two hybrids (DR x PN) were utilized (76 x PN) to assess the susceptibility or resistance to ethylene. The experimental design was completely randomized, with four replications. First, 19 morphoagronomic characteristics were analyzed when the plants had 30% of fruits at the ripe stage. At this stage, the pots were transferred to a room at 25oC with 8-10 µmol/s/m2 of white fluorescent light. Afterwards, the pots were placed in a 60-L container and treated with ethylene at final concentration of 10 µL/L. The plants were exposed to ethylene for 48 hours and then kept at room temperature for further analysis. Afterwards, the number of leaves and fruits was determined at time zero and after 144 hours after end of the ethylene treatment. The Pearson correlation was calculated for each pair of variables and submitted to t-test (p≤0.05). We observed high occurrence of a significant positive correlation (>0.95) between leaf abscission and the anther length, major fruit width, pedicel length, pericarp thickness and dry matter content of the fruits. No significant correlation between fruit abscission and morphological evaluated variables was found. These results show the possibility to use morphological measurements to select plants resistant to leaf abscission induced by ethylene, while for the abscission of fruits, No relation to the morphological parameters evaluated in this experiment was possible to be established.

Diversidade e seleção em população segregante de pimenteiras ornamentais (Capsicum annuum L.)

“…Estes resultados indicam que estas características são mais importantes para explicar a dissimilaridade entre os indivíduos estudados (Costa et al, 2020) e estas, devem ser priorizadas para auxiliar na seleção de genótipos superiores (Nascimento et al, 2015).…”

“…Por outro lado, características que contribuem pouco ou quase nada, dificulta a seleção, podendo estas serem descartadas, pois estes caracteres contribuem com um percentual muito baixo ou não contribuíram para a variabilidade detectada (Rêgo et al 2003;Nascimento et al, 2015).…”

“…O tratamentos fitossanitários foram feitos, quando necessário, durante todo o ciclo, a fim de minimizar os danos causados por pragas e doenças. Quando as plantas estavam prontas para comercialização, com pelo menos menos 50% de frutos totalmente maduros (Nascimento et al, 2015), foram realizadas as caracterizações.…”

Research Article Diallel analysis of quantitative characteristics in ornamental peppers

“…Regarding fruit dry matter content, according to Nascimento et al (2015b), there is a direct relationship between increase of this content and greater abscission of ornamental pepper leaves due to the deleterious effects of ethylene. The favorable negative ĝi values for fruit dry matter content were expressed by UFSJ 4, UFSJ 5, UFSJ 6, UFSJ 7 and UFSJ 8 genotypes (Table 4).…”