Thanh Toan Le et al., JVE, Journal of Vietnamese Environment
Fruit rot caused by Aspergillus niger or Colletotrichum musae is an important post-harvest disease on orange, chilli and Cavendish banana fruits.
The use of synthetic fungicides has been a traditional strategy for the management of the fruit rot disease, but these chemicals adversely affect human health and environment.
Therefore, the objective of this study was to evaluate the effects of CaCl2 on in vitro hyphal growth and in vivo lesion inhibition.
First, aqueous solutions of CaCl2 at three concentrations of 20, 40 and 60 mM were assessed for their inhibitory effect against hyphal growth in vitro.
Next, mature fruits were immersed into a solution of 20 mM CaCl2 for 20 - 30 s, then inoculated by a pathogen suspension at the density of 106 conidia mL-1 and observed for 12 days.
The results showed that 20 mM CaCl2 was the most effective concentration in antifungal assay to Aspergillus isolated from orange rot. The treatment of CaCl2 continued to gain efficacy on limiting lesions’ development on orange fruits until 12 days after inoculation (DAI).
On chilli, CaCl2 at concentrations of 20 and 40 mM inhibited well on the growth of Aspergillus hyphae isolated from chilli rot. However, calcium treatment was not effective on chilli fruits.
On Cavendish banana, solutions of CaCl2 at concentrations of 20, 40 and 60 mM highly limited fungal growth of Colletotrichum in vitro conditions.
The application of CaCl2 solution could inhibit anthracnose lesion length of Cavendish banana variety, but its efficacy did not prolong until 6 DAI.
In general, the good results were obtained from the 20 mM CaCl2 in almost all the studied assays.
Management of rot diseases on fruits by employing 20 mM CaCl2 could be suitable to replace the current hazardous agro-chemicals.
Efficacy of CaCl2 against some important postharvest fungi on orange, chilli and Cavendish banana fruits
Thanh Toan Le, Trong Ky Vo, Thi My Linh Nguyen, Phuong Linh Trieu, Van Toan Ngo & Huy Hoang Nguyen
College of Agriculture and Applied Biology, Can Tho University, 3/2 Str., Can Tho city, Viet Nam
JVE, Journal of Vietnamese Environment, Vol 10 No 2 (2018)