GROWTH , YIELD AND QUALITY OF BANANA ( MUSA SAPIENTUM L ) INFLUENCED BY DIFFERENT BANANA VARITIES / LINES AND PLANTING TIME

A study was carried out to find the optimum planting time and suitable variety on quantity and quality of fruit of banana at the Regional Agricultural Research, Station, Ishurdi, Pabna, Bangladesh during 2009-2010. Six planting time viz, 15 September, 15 October, 15 November, 15 February, 15 March and 15 April and three varieties cv. sabri, ITC-1441 and BARI-kala-1 were used. The plant of 1 November planting were shorter in height (250cm) minimum crop duration was recorded in February planting (328.7 days) while it was maximum in September planting (454.2days). Among planting time, October planting time had higher bunch weight (19.5kg). Significantly higher bunch weight (15.3kg) was obtained from BARI-kala-1. In case of planting time and variety interaction October planting and BARI-kala-1 produced higher bunch weight (23.6kg) and number of finger per bunch (200). It was concluded that October planting and BARI-kala-1 combination is the best in Ishurdi region of Bangladesh


INTRODUCTION
Banana (Musa Sapientam L) is the best known tropical fruit.It is one of the economically important fruit crops grown in Bangladesh both in homestead and commercial farms (Ahmed 1984).The area under banana in Bangladesh is about 58,000ha and the annual production is about 1,004,520t (BBS 2009).
Banana planting is done all the year round in order to secure better prices during off-season.Its market price greatly fluctuates in different month which directly affects the farmer's income (Haque 1984).Sometimes, flesh of banana plant is found to have hard lumps.Due to this, it is very difficult to cultivate banana in Ishurdi region.Cool weather and prolonged drought retrial growth banana plants need at least 25mm (1.0in) of water per week of good growth, more under some conditions for optimum development (Robinson, 1996).Khan (2002) and Hoque (2004) postulated the avoiding of cold weather in December to January and high rainfall in July to August for planting banana.In southern Queensland the optimum time of planting is between September and mid December (Broodly 1994).The season of planting of banana varies between the various states.Banana are grown all through the year, while the peak season vary in different parts of the country and regions.In view of the different divergence of climatic and soil condition in our country.Inspite of its unique postion among the fruit crops of Bangladesh, limited studies have been regarding yield potential of different varieties under different agro-ecological zone of the country have been conducted.Scientist have different opinion and recommendation about planting season of banana.Therefore, the present study was aimed to find out the most suitable variety and optimum planting time for the best growth and yield of banana in Ishurdi region of Bangladesh.

MATERIALS AND METHODS
The experiment was conducted at the experimental field of Regional Agricultural Research Station, Ishurdi, Pabna in Bangladesh during 2009-2010.Three banana varieties viz; sabri, BARI kala-1 and ITC-1441 and six planting times 15 th September, 15 th October, 15 th November, 15 th February, 15 th March and 15 th April were included in this trial.The experiment was laid out in RCBD (Factorial) with three replications.Experimental area is situated at 24.03 0 N latitude and 89.05 0 E longitude at an elevation of 16m above sea level, with mean annual rainfall of 1775mm.The warmest (36 0 c max.) and coldest (10.3 0 c max.) months are June and January, respectively.Experiment plot was clay loam in texture belonging to high Ganges River flood plain under AEZ 11.The selected plot was well drained having pH value 8.5.Plot size was 4m*4m which included four plants per plot.The sucker were planted in pits or 60cm 3 size.Pits were filled with top soil and thoroughly mixed with farmyard manures @ cow dung 85 tons, TSP-1500kg, and gypsum 60 kg per hectare during land preparation.The plants were side-dressed with urea and MP @ 1540 kg and 1850kg ha, respectively, in four installments starting from two months after planting.Weed control measures were adopted in field accordingly.All management practices such as hoeing, mowing, mulching, irrigation, desuckering, propping, spraying, fungicides and insecticides were done according to recommendation.Data in respect of vegetative characteristics, quantitative and qualitative contributing characteristics of fruits were recorded.Banana bunches were harvested with a curved knife when fruits were fully developed, 75 percent mature, angles were becoming less prominent and fruits of per hands stated to change their colour from dark green to light green.The bunch after harvest were kept at room temperature (13.2 0 c) for ripening.Weight of selected bunches was measured just after harvest.TSS percentage was determined by hand refractometer (ATAGO IN Brix 0-32% Japan).The flesh of banana was taken in tip of refractometer.In refractometer scale was 0-32, where dark colour was arise in scale.The data were analyzed statistically means were separated by DMRT.

Varietal effect of growth parameter
A highly significant variation was observed among the varieties/lines in respect of pseudostem height (Table 1).Maximum pseudostem height (3.1m) was obtained from local sabri.This result are in agreement with the findings of Ghose et al. (1992).BARI-kala-1 produced minimum pseudostem height (1.8m).ITC-1441 produced the maximum number of green leaves per plant (13.5) at shooting stage.This corroborated with the findings of Hoque et al. (2007).The highest number of yellow leaves (3.4) are found in sabri and lowest (2.8) in ITC-1441.Maximum number of sucker (8.7) was produced by sabri and lowest (7.2) in BARI-kala-1 at shooting.The base girth of the banana varieties/lines ranged from 55 to 73.0cm.The base girth of sabri was significantly highest (73cm) as compared to other varieties/lines which was  et al. (1992).

Planting time effect on vegetative growth
The results in respect of vegetative growth are presented in  Hoque (2006) and Haque (1984).
Maximum number of yellow leaves (4.1) was found in February planting while the minimum (2.7) was found in October planting.September planting had more number of suckers (14.7) compared to other plantings.The results is in agreement with the findings of Ghose et al. (1992).Planting time did not influenced on base girth at shooting.October planting had the maximum top grith (39.8cm) which was statistically identical to September and November planting 39.3cm and 39.4cm, respectively.September planting had longer duration (454.2days) while February planting took least duration (328.7days).This result corroborated with the findings of Ghose et al. (1992).Crop may vary due to edaphic, climatic and management factors.It is very complex to explain.However, while all the factors are similar in all the treatments, it might be the difference in edaphic and climatic factors at different stages of plant growth which ultimately determine crop duration.

Quantitative and qualitative related factors effect on varieties
Quantitative and qualitative contributing characteristics of varieties differed among the treatments for pseudostem weight, number of bunch, single fruit weight, bunch weight, fruit length, fruit breadth, yield (t/ha), weight of flesh, weight of skin, TSS% and edible portion (Table 3).(1992).The highest number of fingers per bunch (170) was obtained from October which was significantly differed from the others treatment.The longest fruits were recorded in November planting (13.5cm) which was statistically identical to October planting (13.2cm).October planting had the fruits of maximum breadth (12.3cm) closely followed by November (12.3cm),March (12.2cm) and April (12.2cm).October planting stood first (47.4t/ha) against minimum yield from April planting (34.9 t/ha) (Table 4) which was statistically differed from the others.The results were in support of Hoque (2006).
Weight of flesh was highest in October Interaction effect was also significantly in case of pseudostem weight, number of hand

CONCLUSION AND RECOMMANDATION
From the above result of the experiment it may be inferred October planting and BARI Kala-1 combination is the most suitable for banana production in Ishurdi region of Bangladesh.

Table 2 .
Early shooting (242. 2days) was found in February planting.Similar results were reported by Bahri et al. 2002.The late shooting was recorded in September planting (375.2days).February planting had the maximum pseudostem height (262.8cm) which was statistically identical to September, March and April Planting 260.2cm and 259.7cm, respectively.Maximum number of green leaves was found in October planting (14.6) which was significantly differed from the other plantings.The results are in agreement with the findings of

Table 2 : Vegetative growth of banana as affected by planting date
Sabri produced the highest pseudostem weight (2.6kg) while the least (2.1kg) was recorded in ITC-1441.The highest number of hands per bunch (10.3) was obtained from ITC-1441 which was statistically differed from the others.The fruits of BARI-kala-