Effect of Sucker Weight on Quality of Banana (Musa spp.) cv. Barjahaji (AAA)

A field experiment was undertaken at the Experimental Farm, Department of Horticulture, Assam Agricultural University, Jorhat during 2003-2004. The experiment was set in Randomized Block Design (RBD) consisting of three replications and eight treatments. The treatments comprised of T1: 500 g, T2: >500-1000 g, T3: >1000-1500 g, T4: >1500-2000 g, T5: >20002500 g, T6: >2500-3000 g, T7: >3000-3500 g and T8:>3500-4000 g.The results revealed that the quality parameters attributes were non significantly influenced by the treatments. It was evident that T4 showed highest weight pulp (73.41gm), non-reducing sugar (9.69%) and total sugar (13.13%), T5 highest peel weight (42.66gm), titrable acidity (0.23%), T1highest fruit moisture (74.17%) and reducing sugar (3.81%), T7 Highest pulp-peel ratio (1.79), T6 Total soluble solids(22.21%), T2 Sugar acid ratio (59.38).


INTRODUCTION
Banana is one of the most favourite fruits in India. Banana has a long period of domestication in India with its mention in Kautilya"s "Arthasastra" (250-300 B.C.) as well as in the paintings and sculptures of Ajanta and Ellora (300-400 B.C.) In many parts including Assam, the fruits as well as the plants are exclusively used in all auspicious occasions such as wedding, festivals and for worshipping God. It provides a more balanced diet than many other fruits, containing sufficient amount of carbohydrate, the source of energy and as such it is called the wholesome fruit. Owing to its multifaceted usesand high economic returns, banana is referred as "Kalpataru" (a plant of virtue) in India. Banana is also employed as medicine for curing many ailments in NE region. An acre of banana yields fifteen million calories of energy as compared to one million calories of energy produced by wheat (Madhava Rao, 1984).
It contains 61.4 per cent moisture, 1.2 per cent protein, 0.3 per cent fat, 0.7 per cent mineral matters, 27.0 per cent carbohydrate, 80 ppm Ca, 290 ppm P, 6 ppm Fe. It also contains traces of Vit-A, 150 mg Vit-B, 0.5 mg Nicotinic acid, 30 mg Riboflavin, 1 mg Vit-C and 67-137 calorific value per 100 g of pulp (Anon, 1979). Considering the nutritive value and fruit value of banana, it could be considered as "poor man"s apple".
India is considered the largest producer of banana in the world producing 15.07 million tonnes from an area of 0.49 million hectares (Chadha, 2001). Assam holds the fourth rank with an annual production of 600.8 thousand tonnes occupying an area of 43.3 thousand hectares (Bhattacharyya, 2001).The commercial banana is parthenocarpic and effectively seed sterile and is propagated by vegetative methods. Sucker is the major planting material for commercial expansion of banana. The weight of sucker has marked effect on crop duration, growth and yield. However information on the effect of sucker weight on banana fruit quality is not adequate under the agroclimatic condition of Assam.

MATERIALS AND METHODS
The experiment was undertaken in the Experimental Farm of Department of Horticulture, Assam Agricultural University, Jorhat-785013, during the year 2003-2004. The experimental soil was sandy loam in texture, well drained and having pH 5.5. The experiment was set out in Randomized Block Design (RBD) consisting of eight treatments replicated three times. The area of the experimental plot was 915.84 sq.m. and that of the individual plot was 5.4 m x 5.4 m (29.16 m 2 ). Suckers were planted at a spacing of 1.8 m x 1.8 m. The suckers of different weight range were considered as the treatments. The treatments consisted of T1 (<500), T2 (>500-1000), T3 (>1000-1500), T4 (>1500-2000), T5 (>2000-2500), T6 (>2500-3000), T7 (>3000-3500) and T 8 (>3500-4000). "Barjahaji", a high yielding commercial variety of banana in Assam was identified as the material for this study. Fingers are long and green even at ripening. Flesh is soft and smooth. Healthy suckers of uniform age (about 3 month) and different weights were selected as the planting material. Before planting the top portion of the selected suckers were removed at 30 cm from the corm. The weighed suckers were pared and pralinaged by dipping them in a clay slurry with Carbofuran 3G @ 40 g per sucker. The treated suckers were kept over night for suberization and planted in the field on April 8, 2003. Nitrogenous and Potassic fertilizers @ 240 g Urea (46% N) and 600 g Muriate of potash (60% K 2 O) per plant respectively were applied in three splits in third, fifth and seventh month after planting. The whole amount of phosphatic fertilizer @ 210 g Single Super Phosphate (16% P 2 O 5 ) per plant was applied in third month after planting.

Observations on the fruit quality Determination of fruit moisture
For determining moisture of the fruit, the middle fingers from the second hand were selected. The whole weight of the fruit was noted. Representative sample of about 20 g was taken and subjected to oven drying as per the method of Ranganna (1986). The difference between the initial and final weights of the sample gave the moisture content of the fruit and was expressed in percentage. Pulp and peel weight Mean weight of pulp and peel of five uniformly ripe fruits was recorded separately and expressed in gram (g).

Pulp-peel ratio
Pulp-peel ratio was calculated by the following formula.

Total soluble solids (TSS)
TSS of the fruits was determined by the Zeiss Hand juice Brix Refractometer and the result was expressed in per cent (%).

Titrable acidity
Titrable acidity, reducing sugar, total sugar and non-reducing sugar were estimated by adopting the standard method of A.O. A.C (1975).
For estimation of titrable acidity, 10 g pulp was ground in mortar and added 100 ml of distilled water and filtered. Ten ml of filtrate was titrated against 0.1 N NaOH using phenolphthalein as indicator. Titrable acidity was expressed in percentage in terms of anhydrous citric acid.

Reducing sugar
Four ml of saturated lead acetate and 2g of potassium oxalate were added to 10 g pulp which was already ground in a mortar and the volume was made upto 100 ml with distilled water, centrifuged and then filtered. The filtrate was titrated against 10 ml boiling Fehling"s solution mixture (5 ml of Fehling"s solution A+ 5 ml of Fehling"s solution B) using methylene blue as indicator. Deep brick red colour of the solution indicated the end point and the value was expressed in percentage.

Total sugar
From the solution of 100 ml made up for reducing sugar estimation, 25 ml of the solution was taken and 2.5 ml of concentrated HCl was added to it and kept overnight. The solution was then neutralized with 1 N NaOH, made upto 75 ml with distilled water and titrated against 10 ml boiling Fehling"s solution. From the titre value, percentage of total sugar was calculated as follows -Total sugar = (% sucrose + % reducing sugar) Sucrose% = (% Total inverted sugar -% Reducing sugar) x 0.95 Factor = 0.05 (mg of invert sugar)

Non-reducing sugar
Non reducing sugar was calculated from the difference between the total and reducing sugars.

Sugar-acid ratio
The sugar acid ratio was calculated by dividing the value of total sugar by titrable acidity.

Determination of fruit moisture
The data on fruit moisture are furnished in the Table 1. It revealed the non-significant differences in fruit moisture due to effect of various treatments. The highest fruit moisture content was recorded in T 1 (74.17%) followed by T 7 (73.99%). The lowest fruit moisture content was recorded in T 2 (72.25%) and followed by T 3 (72.46%) which was at par.

Weight of pulp and peel
The data on weight of pulp and peel are presented in Table 1.It was found to be nonsignificant due to various treatments. The highest pulp weight was recorded in T 4 (73.41g) followed by T 1 (73.39g) which were at par. The lowest pulp weight was recorded in T 3 (71.73g) and followed by T 6 (72.36g). Similarly the highest peel weight was recorded in T 5 (42.66g) followed by T 4 (42.53g) and were at par with each other. The lowest peel weight was recorded in T 7 (40.80g) and followed by T 6 (40.97g).

Pulp-peel ratio
The data on pulp-peel ratio of fruit are presented in Table 1. It showed non significant differences due to different treatments. The highest pulp-peel ratio was recorded in T 7 (1.79) and followed by T 2 (1.77) and T 6 (1.77). The lowest pulp-peel ratio was recorded in T 5 (1.70) followed by T 4 (1.73).

Total soluble solids (TSS)
The data on total soluble solids (TSS) are furnished in Table 1. The effect of sucker weight on TSS was found to be non significant. The highest TSS was recorded in T 6 (22.21%) followed by T 2 (22.19%) and T 4 (22.18%). The lowest was recorded in T 7 (20.45%).

Titrable acidity
The data on titrable acidity are presented in Table 1. The treatments showed nonsignificant differences on titrable acidity. T 3 (0.20%) showed the reduced titrable acidity of the fruit which was of similar magnitude with T 8 . The highest titrable acidity was recorded in T 5 (0.23%) which was followed by T 4 (0.22%).

Reducing sugar
The data on reducing sugar are shown in Table  1. It indicated non significant variation due to different treatments. The highest reducing sugar content was recorded in T 1 (3.81%) followed by T 4 (3.44%) while T 3 (3.10%) recorded the lowest reducing sugar content.

Non-reducing sugar
The data on non-reducing sugar are given in Table 1.It showed non significant influences due to effect of different treatments. T 4 (9.69%) produced the highest non-reducing sugar content followed by T 5 (9.44%) while T 3 (8.07%) treatment gave the lowest nonreducing sugar content among all the treatments.

Total sugar
The data on total sugar are presented in Table  1.It had non-significant influence on total sugar content in fruits. The highest total sugar content was recorded in T 4 (13.13%) and followed by T 5 (12.76%). The lowest total sugar content was recorded in T 3 (11.17%).

Sugar-acid ratio
The data on total sugar-acid ratio are furnished in Table 1.Non-significant differences in sugar-acid ratio were recorded due to different treatments. The highest sugar-acid ratio was observed in T 2 (59.38) treatment followed by T 8 (58.72) and T 4 (58.71) which were at par while T 7 (54.16) treatment registered the lowest sugar-acid ratio.

DISCUSSION Effect on fruit quality
It is interesting to note that the sucker weight did not exhibit any significant effect on the quality of fruit. In the present study, the TSS, pulp weight, reducing sugar, total sugar, titrable acidity, non reducing sugar and sugaracid ratio were not significantly influenced by sucker weight. Lower reducing sugar may be due to low conversion of sugars from starch under such environmental condition. The acidity was due to slow conversion of organic acid to sugar while TSS was due to slow deposition of solids and also slow conversion of organic acid to sugar. Low sugar acid ratio might be due to low proportional assimilation of acid to sugar in the fruits.
Data from the experiment revealed that the treatment T 4 obtained the highest pulp weight (73.41g), non-reducing sugar (9.69%) and total sugar content (13.13%). This result is supported by the findings of Norman (1976) in pineapple and Rodriguez and Irrizarry (1979) in banana. Prasanna and Aravindakshan (1985) had similarly noticed that the fruit quality characters namely TSS, acidity, total sugar, reducing sugar, non reducing sugar and sugar-acid ratio were not influenced by the sucker weight in banana cv. Palayankodan.

CONCLUSION
From the experiment it could be concluded that use of suckers weighing 1500-2500 g would be profitable proposition for good fruit quality of Barjahaji banana under the agroclimatic condition of Jorhat, Assam, India.