Ethylene production as a possible indicator of wound healing in roots of several sweet potato cultivars

Abstract

Fleshy roots of 18 sweet potato cultivars were wounded and cured for 12 days . Significant differences were found between cultivars for ethylene production, cell lignification, and wound periderm formation . Average ethylene production, the number of days ethylene was produced, or the day of peak ethylene production showed nonsignificant and low (r2 = 0 .40) correlations with cell lignification or wound periderm formation ; however, multiple regression analysis indicated statistically significant and moderate correlations between selected daily ethylene production and cell lignification (r 2 = 0 .74) and wound periderm formation (r2 = 0 .73) . These observations suggest that measurement of ethylene produced by wounded sweet potato roots may be useful in helping screen large numbers of sweet potato breeding lines and their progeny for the ability to produce lignified and wound periderm cell layers . Wound healing, however, is only one aspect of good storage capability in sweet potato cultivars .

Shelf life extension of sweetpotato (Ipomoea batatas (L) Lam) storage roots using household-level storage methods

“…However, in our present study, OFSP-2, though had the highest lignification score, did not store better than OFSP-1 and WFSP (Figure 4). Our findings support previous suggestions that other factors aside from lignification (Amand and Randle, 1991;Walter et al, 1989) could be responsible for sweetpotato shelf life extension of the cultivars investigated in this study.…”

“…Curing encourages the formation of lignified/suberised wound periderm tissue at the wound sites which reduce moisture loss and microbial infection, reducing root decay (Ravi et al, 1996;Ray and Ravi, 2005;Sowley and Oduro, 2002). However, other factors aside from wound healing through lignification are considered in selecting cultivars with good storage potentials (Amand and Randle, 1991;Walter et al, 1989). Although found to be beneficial, curing is hardly practised by farmers in the tropics but may occur naturally where ambient conditions are moist and warm (Ravi et al, 1996;Woolfe, 1992).…”

Sweetpotato cultivars differ in efficiency of wound healing

“…The thickness of the wound periderm may vary according to the cultivar. Morris and Mann (1955) found thicknesses varying from 4 to 10 layers while Walter and Schadel (1983) and St Amand and Randle (1991) reported thicknesses between 5 and 6.7 layers. Walter and Schadel (1982) considered a wound periderm needed to be approximately 4.2 cell layers thick to be effective against water loss and pathogen invasion.…”

“…Some variability has been found among sweetpotato cultivars in the rate of wound healing (Strider and McCombs, 1958;St Amand and Randle, 1991). However, very little is known about the wound healing characteristics of African germplasm, how this relates to shelf-life and also how the process is affected by sub-optimal humidities.…”

Shelf life extension of sweetpotato roots using household-level storage method

“…Curing encourages the formation of lignified/suberised wound periderm tissue at the wound sites (Tomlins et al, 2010) which reduce moisture loss and microbial infection, reducing root decay (Ravi et al, 1996;Ray and Ravi, 2005;Sowley and Oduro, 2002). However, other factors aside from wound healing through lignification are considered in selecting cultivars with good storage potentials (Amand and Randle, 1991;Walter et al, 1989). Although found to be beneficial, curing is hardly practised by farmers in the tropics but may occur naturally where ambient conditions are moist and warm (Ravi et al, 1996;Woolfe, 1992).…”