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Maturity Indices of Watermelon

Maturity Indices of Watermelon

Miss. Tin Tin Hla Assistant Manager

Myanma Agriculture Produce Trading Ministry of CommerceUNION OF MYANMAR

 

Myanmar • Neighbor to China, India, Neighbor to China, India,

Laos, Bangladesh, Thailand.Laos, Bangladesh, Thailand.

• 99°°.58’.58’ to 28°31’ to 28°31’ Latitude Latitude

• 9292°°.9’ to 101.9’ to 101°°.10’ Longitude.10’ Longitude

• Area : 676,756 kmArea : 676,756 km22

• Extended about 2361 km Extended about 2361 km

from north to southfrom north to south

• About 1078 km from east to About 1078 km from east to

westwest

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Climate• Three typical seasons

Rainy : mid- May to mid-October

Cool dry : mid- October to mid-February

Summer : mid- February to mid- May

• Annual rainfall : 2540-5080 mm in coastal & hilly regions.

: 760-1015 mm in central Myanmar

• Temperature : different ranges

: 30° - 40° C from coastal regions to

central.

: : 4° - 20° C in mountainous and plateau. 3

Importance of Agriculture for MyanmarImportance of Agriculture for Myanmar Importance of Agriculture for MyanmarImportance of Agriculture for Myanmar

Major Fruit Crops in Myanmar

• Mango• Banana• Melon• Pineapple• Papaya• Pummelo• Grape• Oranges

Market Display in Fruit Stall

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Production Status of Vegetables in Myanmar (2010-2011)

Sr. Name of Vegetable Sown Area (ha)Total Production

(ton)

1 Chili 129027 115467

2 Onion 70934 1029841

3 Garlic 28667 200565

4 Potato 36676 528977

5 Cabbage 28463 448752

6 Cauliflower 23432 310252

7 Lettuce 7758 52065

8 Mustard 33069 230898

9 Tomato 105934 1235571

10 Carrot 2313 23385

11 Radish 19808 249121

12 Watermelon 15073 203795

13 Bottle Gourd 19210 221344

14 Asparagus 372 1529

15 Other vegetable 225849 -

Total 746582 4851562

The price of muskmelon keeps going up in Muse 105th Mile Border Trade Zone in Muse District, Shan State (North).

• Last year about 150,000 tonnes of melons, worth US$1.5million, were exported, according to Fruit Association statistics.

• The current wholesale price of a melon ranges from K800ks to K2500ks, up from last year’s K800-K1500ks.

• Watermelons is grown all over the country, mostly in lower and upper Myanmar and other States and Divisions where weather conditions is sound and favorable.

• Renown for better eating quality of watermelons are those grown in Sagaing Region and Myingyan, upper Myanmar, and Kayan, Minhla and Tharyargone in lower Myanmar.

• The fruit now on the market is from Myingyan. Wholesalers say wet weather this year has reduced the harvest, and the quality has also been reduced by poor-quality fertilizer. Foreign cultivars from China and other Asian Countries are also introduced and grown widely along with Myanmar ones.

Introduction

Objectives of the study• In Myanamr, most of the watermelon growers, brokers, distributors and

buyers rely on traditional methods of determining the maturity of it by thumping it and listening the sound. Next is to see the tendril which will wilt and change from a healthy green color to a partially desiccated brown color. In addition to this, several destructive indices are also used on randomly selected fruit to predict harvest maturity of the remaining fruit in the field.

• Maturity, cultivar (cv), size, shape and soluble solids are among the characteristics that determine quality of watermelons. Because judgment of watermelon eating quality from external appearance is very difficult, there is a continuing problem of poor quality at the markets.

• It is generally accepted that there are good correlations between maturity, sugar content and soluble solids of melons as measured with a hand refractometer. The soluble solid content (SSC) of the watermelon juice is another measurement of harvest maturity and now it is the main objective of this study by using refractometer, to determine the right maturity indices for optimum eating quality

Methodology• Sampling : 3 lots of 5 watermelons each from

three varieties were obtained from commercial growers at Hlegu region ,Yangon Division. They were selected to represent the varying maturities and sizes.

• Measurements. Watermelons were measured as follows:

• a. Length —distance between stem and blossom ends.

• b. Diameter —largest equatorial diam at right angle from stem to blossom end.

• c. Rind thickness —width of no edible region at blossom end and on the side, midway between the two ends.

• For each lots of watermelon, samples of two longitudinal slices are taken, one from the side that touched the ground during growth and one from the opposite. Then samples from three regions of each slices, namely, the center, the top and the bottom ,are taken, crushed to pulp and juice are measured 3 times accordingly.

• The percent soluble solids of three regions from the side that touched the ground from first lot (855 variety) ranged from 9 (the center), 8.3(the top) and 8.2(the bottom) and averaged 8.5. The percent soluble solids of three regions from the opposite ranged from 10.3(the center),8(the top) and 8.2(the bottom) and averaged 7.8.

• The percent soluble solids of three regions from the side that touched the ground from second lot (164 variety) ranged from 8.5 (the center), 7.5(the top) and 8.5(the bottom) and averaged 8.2. The percent soluble solids of three regions from the opposite ranged from 9.3(the center), 7(the top) and 7.5(the bottom) and averaged 7.9.

• The percent soluble solids of three regions from the side that touched the ground from third lot (Myanmar variety) ranged from 9.5 (the center), 8.5(the top) and 8.2(the bottom) and averaged 8.7. The percent soluble solids of three regions from the opposite ranged from 9(the center), 7.5(the top) and 8.2(the bottom) and averaged 8.2.

Results • The three cultivars sampled are the principal ones currently grown in Hlegu and

the shape of each is a genetic characteristic that remains relatively constant for various melon weight ranges.

• All the samples from each lot are seen not too different in their correlations among the solids in different regions. It is found that the sweetest region is the center of each lot and the other two regions are more or less nearly the same in their soluble solids content respectively.

• Another significant indicator is that the percent soluble solids at the center of opposite slices of each lot are maximum in sweetness respectively.

• The soluble solids content of composite juice of each slice is similar to the center one and it can be assumed to represent the entire edible flesh.

Variety CenterBrix

TopBrix

BottomBrix

AverageBrix

855 9 8.3 8.2 8.5

Ground Touch

855 10.3 8.0 8.2 7.8

Opposite

164Ground Touch

8.5 7.5 8.5 8.2

164Oppositeou

9.3 7.0 7.5 7.9

Variety CenterBrix

TopBrix

BottomBrix

Comp siteBrix

GoldenCrown

9.5 8.5 8.2 8.7

Ground Touch

Opposite

9.0 7.5 8.2 8.2

Brix Chart (partial)

from International Ag Labs, originally produced by Dr. Carey Reams

Conclusion• From the study it is obvious that the common use of

traditional methods of watermelons growers to assess the maturity indices is relatively useful for their purpose. But to get the better eating quality of watermelons, it is very important to know the right harvest time.

• From my study I have known that watermelons are harvested at the right time and only a few watermelons are seen to be deviate from the range of percent soluble solids contents measured and this may be early harvested than the right time.

Constraints and lessons• For the most watermelon growers in Myanmar, they are not

able to use modern tools to make decisions when to pick the fruits except relatively for a few rich farmers. So they are still using the traditional methods.

• In addition to this, the climate change is a major problem and some plantations were severely submerged due to late and heavy rainfall. So I had a narrow chance to go and study thoroughly. I had to narrow the scope of my study and make the action plan as possible as I can.

• But I hope it can help me understand to know the real picture of watermelon growing in Myanmar to some extent.

Recommendation• Whatever it may be, I have a great chance to study the maturity indices of

watermelons as an action plan assigned by Mekong Institute in connection with the training on "Postharvest Practices" held on 28 March to 8 April 2011.

• From this training and other related information, I have much knowledge and experiences of postharvest practices which are very useful not only for me but also the fruit growers and other involved in this field. My country is still developing one and still lags behind some Asian countries in its respective fields including agriculture and horticulture so the country is trying to build all around capacity building, infrastructural building and human capacity building.

• So it is timely and good chance for me to take part in this training as a token of reward from Mekong Institute and I deeply appreciate it and thank for that. In the future, Mekong Institute, I hope, should continue its rendering of technical know-how to neighboring countries like mine in the field of post harvest practices in agriculture for the benefits of all of us.

Thanks

for

attention