TITLE:
Influence of Harvest Periods on Cassava (Manihot esculenta Crantz) Agronomic Traits and Physiological Response to Post-Harvest Physiological Deterioration
AUTHORS:
Astride Stéphanie Mouafi Djabou, Herman Pascal Kounty Ewane, Victor Jos Evina Eyamo, Franklin Tounkam Ketchiemo, Priscila Gonzales Figueiredo, Nicolas Niemenak, Libert Brice Tonfack
KEYWORDS:
Manihot esculenta, Harvest Period, Post-Harvest Deterioration, Agronomic and Biochemical Parameters
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.14 No.1,
January
31,
2023
ABSTRACT: Cassava (Manihot
esculenta Crantz) is the third largest source of calories in tropical countries and the sixth most important food crop in the World. However,
the short shelf life of its storage roots after harvest due to a rapid post-harvest
physiological deterioration (PPD) makes the roots to be considered as a risky
product to market. The objectives of this work were to investigate the
influence of two harvest periods on cassava agronomic parameters and their
physiological response to PPD. Three cassava cultivars 96/1414, I070593 and LMR
were selected for the experiment and harvested at 10 and 12 months after
planting (MAP). The response to PPD was assessed during storage at 0, 3, 8 and
15 days after harvest (DAH). Total proteins content, soluble sugars and starch,
total polyphenols compounds, polyphenoloxidase and peroxidase activities were
recorded during storage. Results showed large variation among the parameters at
the two harvest periods across the cultivars. High number of tubers was recorded in all the cultivars at 12
MAP and a significant increase in storage roots length was observed in 96/1414
and LMR from 10 MAP to 12 MAP (25 ± 5.1 to 41.3 ± 5.9 and 22.6 ± 3.3 to
27.9 ± 4.8) respectively. A reduction of about 49% of tubers weight was
observed in I070593 from 10 to 12 MAP while
an increase of about 36% and 11% were recorded in LMR and 96/1414
respectively. Tubers from I070593 showed less susceptibility to PPD when
harvested at 10 MAP compared to those from LMR and 96/1414 where less
susceptibility to PPD were recorded at 12 MAP. An increase in soluble sugars
content, total proteins content and peroxidase activity subsequently to a
decrease in starch content were recorded during storage from 8 to 15 days after
harvest especially at 10 MAP in I070593 and at 12 MAP in LMR and 96/1414. High
content of total phenolic compounds and less activity of polyphenol oxidase
were correlated to PPD susceptibility. This work opens a new insight issue of
the consideration of the appropriate harvest time of the cultivars as a tool to
better control the onset of postharvest physiological deterioration.