汇报人：张莹

指导教师：寇晓虹副教授

The Effects of Harvest Maturity on Storage Qualityand Sucrose-Metabolizing Enzymes During Banana RipeningThe Effects of Harvest Maturity on Storage Qualityand Sucrose-Metabolizing Enzymes During Banana Ripening

• abstract

• introduction

• Materials and Methods

• Results

• Discussion

Mature green “ Baxi ” banana were harvested at 60% and 80% maturity stages, and evaluate the effects of harvesting at different maturity stages on storage quality and changes in

sucrose-metabolizing enzymes(SPS.SS.AI.NI), fruit firmness, disease index, contents of starch, and total soluble sugars.e-

nzyme activities as sociated with sucrose metabolism was in-

vestigated under natural and accelerated ( treated with ethyl-

ene) ripening conditions.

1.abstract

1.abstract

Treated with ethylene:All the indexes were accelerated dramatically compared with untreated fruit with both 60% and 80% maturity.On the contrary, no significant differences in firmness, sugar, starch,disease index, SPS, SS, AI, and NI were observed between fruit harvested at 60% or 80% maturity.

Natural:Indexes with 80% maturity were significantly faster than those in fruit with 60% maturity.

Conclusion:storage quality and sucrose-metabolizing enzymes of banana fruit stored under natural conditions are related to harvest maturity stage; storage quality of fruit with lower harvest maturity is better than fruit with higher maturity. However, when fruit ripening is acceler-ated by ethylene, the harvest maturity stage has no influence on storage quality and changes in sucrose-metabolizing enzymes.

1.abstract

SPS: 6-P-F+UDPG→6-P-S+UDP

SS: S+UDP→F+UDPG

AI\NI: S+H20→G+F

←

合成蔗糖

两向

分解蔗糖

2.Introduction

Banana:difficult to store,quality and shelf life are limited by excessive fruit

softening and rotting during transport and storage.

When ripening,massive transformation of starch to sugars.

SPS has been suggested to be the key enzyme responsible for

sucrose accumulation in banana fruit.

Fruit maturity at harvest is one with the most impact on storage life.

3.Materials and Methods

Plant Materials and Treatments

Quality Assessment

Fruit Disease Index

Sugar and Starch ContentDetermination

Enzyme Extract ion and Assays

Statistical Analysis

4.Results

Banana Firmness

迅速下降P < 0.05

趋于一致P > 0.05

12Days 35Days

Disease IndexP<0.05

no significant differenceP > 0. 05

乙烯催熟下 10D达到 93自然条件下 80%—18D

60%—35D

StarchContent

Fig. 4 Effects of harvest maturity on starch content during storage in banana ripened naturally (a ) or ripened with ethylene (b). Vertical bars re-resent ±SE of three replications.

P < 0 .05

P > 0.05

Tss

Fig. 2 Effects of harvest maturity on TSS during storage in banana ripened naturally (a ) or ripened with ethylene (b). Vertical bars represent ±SE of three replications.

P > 0.05

Reducingsugar

Fig. 3 Effects of harvest maturity on reducing sugar during storage in banana ripened naturally (a ) or ripened with ethylene (b). Vertical bars represent ±SE of three replications.

P > 0.05

Fig. 5 Effects of maturity stages on SPS activity during storage of banana. Naturally ripened fruit (a) and of ethylene-treated fruit (b). Vertical bars represent ±SE of three replications.

SPS

Fig. 6 Effects of maturity stage on sucrose synthase activity(synthesizing) of banana during storage of fruit naturally ripened (a) and ethylene treated ( b ). Vertical bars represent ±SE of three replications.

SS-SP < 0 .05

NI

AI

P < 0 .05

P > 0.05

P > 0.05

5.Discussion

Our resul ts in this study show that stor age lif e of banana fruit with the

lower harvest mat urity (60%) was longer than that wi th the higher (80%)

harves t maturity.

Under natural ripening conditions, on the same storage day banana fruit

with the higher harvest maturity had higher disease indices,SPS activity,

rates of fruit softening, starch degradation, and total soluble sugar

accumulation than in fruit with the lower harvest maturity.

Our resul ts in this study show that stor age lif e of banana fruit with the

lower harvest mat urity (60%) was longer than that wi th the higher (80%)

harves t maturity.

Under natural ripening conditions, on the same storage day banana fruit

with the higher harvest maturity had higher disease indices,SPS activity,

rates of fruit softening, starch degradation, and total soluble sugar

accumulation than in fruit with the lower harvest maturity.

we suggest that the lower maturity is beneficial to extend the storage

time of banana fruit.

Once banana fruit is treated with ethylene, no significant difference

could be observed between 60% and 80%.

This work demonstrates that it is appropriate to harvest banana at

lower maturity stage and that it is beneficial to use accelerated ripening

method to improve the sugar content before marketing.

we suggest that the lower maturity is beneficial to extend the storage

time of banana fruit.

Once banana fruit is treated with ethylene, no significant difference

could be observed between 60% and 80%.

This work demonstrates that it is appropriate to harvest banana at

lower maturity stage and that it is beneficial to use accelerated ripening

method to improve the sugar content before marketing.

5.Discussion

My thoughts:

研究思路清晰，分别以采收成熟度为 60%和 80%的样品作为研究对象，通过分析淀粉降解度、 TSS含量、多种蔗糖代谢相关酶活性等成熟指标来研究采收成熟度与贮存期成熟变化的关系。相关性明显，实验结果应该是比较完美的。总体来说，实验较为简单，并无复杂设计之处。

My thoughts:

研究思路清晰，分别以采收成熟度为 60%和 80%的样品作为研究对象，通过分析淀粉降解度、 TSS含量、多种蔗糖代谢相关酶活性等成熟指标来研究采收成熟度与贮存期成熟变化的关系。相关性明显，实验结果应该是比较完美的。总体来说，实验较为简单，并无复杂设计之处。

Thank You~~~Thank You~~~