Climatic Adoptability /requirements of Banana

1. Climatic Adoptability /requirements of Banana Next End

2. introduction • The major banana growing areas of the world are geographically situated between the Equator and latitudes 200 N and 200S. • Climatic conditions in these areas are mainly tropical, with comparatively small temperature fluctuation from day to night and from summer to winter. • The banana growing areas of subtropics are situated between 200 and 300 North or south of the equator. • The main climatic characteristic in the subtropics are the wide temperature fluctuations between day and night and between summer and winter, the high and the low rainfall which is also poorly distributed. Previous Next End

3. Bananas perform very well under humid tropical conditions but can be cultivated successfully even under humid or semi arid sub tropical conditions. • The growth and yield of most of the varieties are better at a temperature range of 25-35°C though they can be cultivated at a temperature range of 10-40°C. • A suitable banana climate is a mean temperature of 26.67°C and mean rainfall of 10 cm per month. There should not be more than 3 months of dry season. • Under cooler climates the crop duration is extended. The shooting and bunch development gets affected at temperature less than 10°C. Cont. Previous Next End

4. The growth of the banana plant responds quickly, within a matter of an hour or two to changes in air temperature. All growth ceases as soon as the temperature of the surrounding air falls below 11° C. • As long as the temperature remains 11° C, no growth whatsoever takes place. As the air temperature rises above 11° C growth starts and the growth rate increases gradually at first, and then with rising temperatures, more and more rapidly. • The biggest increase in growth rate for every degree that the temperature rise appears to lie between approximately 19° C and 23° C. Cont. Previous Next End

5. The daily growth at 23° C is, in fact, about double that at 19° C. With further rise in temperature, the growth continues to increase, but more and more slowly as high levels of temperature are reached. • In the experiments conducted, no falling off or even leveling off of the growth rate was observed. • Cool weather and prolonged drought retard growth. Banana plants produce only one leaf per month in winter, 4 per month in summer. If low temperatures occur just at flowering time, the bud may not be able to emerge from the stem. Previous Next End

6. If fruits have already formed, maturity may be delayed several months or completely suspended. If only the leaves are destroyed, the fruits will be exposed to sunburn. • Smudging, by burning dry trash covered with green clippings to create smoke, can raise the temperature 2 to 4 degrees. • Flooding the field in advance of a cold snap will keep the ground warm if the brief chill weather is prevailed. • The brief frosts kill the plants to the ground but do not destroy the corm. A cooking banana, 'Plankel', survives winters in home gardens in northern India. Previous Next End

7. Banana is cultivated under different conditions in India. The temperature, Rainfall and Latitude details of banana growing states in India. Previous Next End

8. Banana comes up well at altitudes ranging from sea level to 1500 m above mean sea level. 'Dwarf Cavendish' and the 'Red' banana are particularly sensitive to cold, whereas the dwarf cultivar 'Walha', or 'Kullen', of India is successful up to 4,000 ft (1,220 m) in the outer range of the Western Ghats. • 'Vellavazhai' is extensively cultivated in the Lower Pulneys between 3,200 and 5,500 ft (975 and 1,616 m). • At higher altitudes, only few varieties like ‘hill bananas’ can be grown successfully as is being practiced in Pulney and Shevroy hills of Tamil Nadu. • They are prone to wind damage in areas where severe winds are experienced. In such areas ‘Dwarf Cavendish’ can be tried for cultivation. Previous Next End

9. Wind is detrimental to banana plants. Light winds shred the leaves, interfering with metabolism; stronger winds may twist and distort the crown. • Winds to 30 mph break the petioles; winds to 40 mph will topple a pseudostem that is supporting the weight of a heavy bunch unless the stem is propped, and may cause root damage in non fruiting plants that are not blown down; winds of 60 mph or over will uproot entire plantations, especially when the soil is saturated by rain. • Windbreaks are often planted around banana fields to provide some protection from cold and wind. Hot winds blowing in high speed during the summer month's shred and desiccate the leaves. Previous Next End

10. Cyclones and hurricanes are devastating and the latter were the main reason for the shift of large scale banana production. • Hail results from powerful convection currents in the tropics, especially in the spring, and does much damage to bananas. • Stagnation of water is injurious and may cause diseases like Panama wilt. In coastal areas of Andhra Pradesh and Tamil Nadu the cyclonic wind damages the plantations. • Hence it is advisable to select areas where mean temperature is around 25-30° C with a mean annual rainfall of 100 mm per month. Previous Next End

11. effects of low winter temperatures The problems which result in a banana plantation from low winter temperatures serve to only emphasize the importance of adequate heat as a factor, in banana production. The most important of these are 'choke throat' 'November dump' and frost damage. Previous Next End

12. choke throat Symptoms • Choke throat is a physiological disorder of bananas. It is also known as choke, choking or choked throat. • In its most severe form the bunch fails to emerge from the top of the pseudostem and instead bursts through the side of the pseudostem. • In less severe cases the top 1 or 2 hands become trapped in the throat of the plant leading to badly misshapen fruit.Because the bunch is not 'thrown' clear of the throat it is both difficult to cover with bunch covers and more susceptible to sunburn damage. • Bunches which experience difficulty in emergence usually have several leaves closely 'bunched' together at the top of the pseudostem. Previous Next End

13. Causes Choke throat is seasonal in nature. It is usually worst in the winter and early spring following cold weather. However, it can also occur following periods of water logging or severe water stress and following wind storms. Two factors contribute to the actual difficulty in bunch emergence. Firstly there is a reduction in the elongation of internodes of the true stem bearing the bunch inside the pseudostem (pseudo = false). Secondly, the stiffness of the leaf bases at the top of the pseudostem can prevent proper bunch emergence Previous Next End

14. Control • Select taller varieties, which are less susceptible to choke, throat, eg Williams. • Choose a warm environment, one which is well protected from frosts and strong winds. • North Queensland has less problems with choke throat than southern Queensland. Slopes facing the north and north west are usually warmer. Previous Next End

15. Control time of bunching to avoid cold weather prior to bunching. Plants bunching in the late spring to mid autumn are less affected. • Good on-farm drainage measures including mounding of rows. • Regular irrigation to avoid water stress particularly during hot-dry weather. • Higher nitrogen rates are thought to be beneficial Previous Next End

16. November dump • Cold temperatures also have a marked effect on bunch development. When the flower initiation occurs during the winter, a characteristically a peculiar bunch can be expected. • The November dump bunch is small and composed of hands of uneven size and often deformed fruits. • The smaller fingers on the hands are, in many cases, fuller at the flower end and thinner at the stalk end. • The flower end is often black, rough and cracked and during a good rainy season, fungal diseases further damage these fruits Previous Next End

17. Another common symptom is the cone-shaped protuberance at the flower end. • This protuberance is pale green in color. The amount of misshapen fruit as November-emerging bunches varies from year to year. • It must be stressed that November dump symptoms are caused by cold temperatures and they are not mineral deficiency or drought symptoms. • A good orchard practice is to cut down all the plants producing severe November dumps. Previous Next End

18. REFERENCE: • Veeraraghavathatham , D., M.Jawaharla, S.Jeeva and R.Rabindran. 1996. Scientific fruit culture. • Chattopadhyay, 1994. A text book on pomology. Kalyani publishers. Ludhiana. • Nakasone, A.Y. and R.E. Paul, 1998. Tropical fruit. CAB international publishing ltd. • Bal J.S., 1997. Fruit growing, Kalyani publishers. Ludhiana • Singh, S.P. 1995. Commercial fruits. Kalyani publishers. Ludhiana. Previous Next End

19. assessment 1. _________and prolonged drought retard growth. Cool weather. 2. The shooting and bunch development gets affected at the temperature ______ a). 10 - 20° C b). More than 20° C c). Less than 10° C 3. _______ and the 'Red' banana are particularly sensitive to cold.( Dwarf Cavendish') 4. _________ varieties are most susceptible to choke throat disorder. a). Tall varieties b). Dwarf varieties 5. November dump symptoms are caused mineral deficiency or drought symptoms (True/ False) Previous End