Banca de DEFESA: DIEGO DIAS RAFAEL

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : DIEGO DIAS RAFAEL
DATA : 31/08/2018
HORA: 10:00
LOCAL: Programa de pós-graduação em Fitotecnia - sala 1
TÍTULO:

Influence of post-harvest application of gibberellin and ethylene on slope and quality parameters of Italian tomato in bunches grown in TOMATEC system

PALAVRAS-CHAVES:

Growth regulators, zone of abscision, fixation of fruits, coloration

PÁGINAS: 75
GRANDE ÁREA: Ciências Agrárias
ÁREA: Agronomia
RESUMO:

The present work aimed to evaluate the influence of the post-harvest application of gibberellic acid (GA3) and the combination of GA3 and ethylene on Italian tomatoes cv. BRS Nagai cultivated under TOMATEC system, aiming the commercialization of the fruits in the bunch. Physicochemical parameters, abscission process, enzymatic activity in the region of fruit abscission and evaluation of ZA formation by optical microscopy in tomato bunches during the storage period were evaluated. The tomato (Solanum lycopersicum L.) has spread all over the world, occupying a prominent place among horticultural products. The abscission process is defined by the separation of cells in the plant material being regulated by the hormonal balance in the region of abscision, regulating the activity of hydrolytic enzymes such as pectinamethylesterase (PME) and polygalacturonase (PG), responsible for changes in cell wall components. The influence of ethylene as an aid to the abscission process was verified, while gibberellin has been extensively studied in order to increase the fixation of fruits in different cultures. Due to the scarcity of jobs with post-harvest application of gibberellic acid (GA3) in tomato fruits, a preliminary experiment was carried out to verify fruit behavior as a function of the treatment used. Cachos de tomate cv. BRS Nagai were harvested at the mature green stage, containing 3 to 7 fruits per cluster. They were treated with 90 ppm GA3 by spray directed to the region of fruit abscission and stored at ambient conditions (24 ± 3ºC and 75 ± 4% RH) for 15 days. There was no significant interaction between treatment and storage period for any characteristics evaluated. For the main experiment, 4-fruits were harvested in the mature green stage. 90 ppm of GA3 was applied by immersion of the clusters for 2 minutes immediately after harvesting and stored under ambient conditions (24 ± 3 ° C ± 4.5% RH). The ethylene treatment was carried out on the first day of storage with application of 150 ppm and the bunches were kept in the box for 24 hours at a temperature of 24 ± 2 ° C and a relative humidity of 95 ± 5%. The results presented significant interaction between the treatments and the period evaluated only for the characteristics of instrumental firmness (N), resistance to tilt (N), coordinate of chromaticity a * and pH. Taking into account that in the present work the application of 150 ppm of ethylene exclusively aimed at the homogenization of the coloration of the fruits within the same bunch, it can be said that, visually, the combination of the regulators was interesting because it provided greater color homogeneity in fruits in the same cluster. To evaluate the formation of the abscission zone, standard clusters were collected with 3 fruits per cluster and treated in the same manner as described for the main experiment. ZA was evaluated by optical microscopy on days 2, 12 and 19 of storage. The obtained images make it possible to verify the influence of ethylene as favoring the formation of ZA and the process of abscision, whereas GA3 delayed the formation of the same, delaying the process of abscission.

MEMBROS DA BANCA:
Interno - 2181674 - LEONARDO OLIVEIRA MEDICI
Interno - 1219728 - REGINA CELI CAVESTRE CONEGLIAN
Externo à Instituição - OTNIEL FREITAS SILVA - EMBRAPA