SUCCESSFUL POLLINATION OF APPLES Farmers in the Himalayas go to great lengths to ensure pollination of their apple crops by Uma Partap, ICIMOD, Nepal

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1 SUCCESSFUL POLLINATION OF APPLES Farmers in the Himalayas go to great lengths to ensure pollination of their apple crops by Uma Partap, ICIMOD, Nepal Himachal Pradesh is in the north-west Indian Himalayas and is known as the 'Fruit State' of India. Apples are the main cash crop of the State, accounting for over 80% of total fruit production. Trees are planted in the mountainous Districts of Kinnaur, Kullu, Shimla and parts of Solan, of which Kullu and Shimla Districts are the major apple producing areas. During the past few years apple production in Himachal Pradesh has been declining continuously. Information gathered by the Beekeeping Project of ICIMOD has shown that this decline in productivity is due to pollination failure. A study was conducted to investigate the problem. In recent years the best apple crop was in Since then there has been a serious decline in productivity (farmers estimate 50%) due to pollination failure. The various reasons are discussed here. LACK OF POLLINISERS A few years ago the farmers had many apple varieties: Commercial, Golden, Jonathan, Red Gold, Kali Devi, Red and Royal Delicious. These provided compatible pollen to other varieties and good fruit set. Since 1980 because of the better market value of Royal Delicious, farmers have uprooted other varieties and planted Royal Delicious on a large scale. All new orchards have been planted only with Royal Delicious. However, Royal Delicious is completely self-sterile and requires pollen from other compatible or polliniser varieties for fruit set to occur. Appropriate ratios of apple pollinisers do not exist and some farmers have no polliniser trees. Farmers are now aware of the need for pollinisers, for good yields and apple quality, and are planting pollinisers. Some farmers are grafting pollinisers on to Royal Delicious trees. Farmers in Shimla District have grafted a polliniser variety called Snowdrift, selected from crab apple, a wild apple variety. Snowdrift acts as the bouquet and has a long flowering period of more than a month, providing pollen to many other varieties, whether early or late blooming. The main polliniser varieties now planted in Kullu District include Kali Devi, Commercial and Golden. In Shimla District the most commonly used polliniser varieties are Golden, Red Gold, Tydemann and Early Worcester. Short-term solution Farmers place polliniser branches in plastic bags filled with water and hang these on Royal Delicious trees. This type of pollination management is called 'Bouquet Pollination', and the polliniser branches 'Bouquets'. Bouquet pollination was first started by Mr Gulab Singh in 1994 in Kullu District. Previously fruit set in his orchard had been down to only 10%, but using bouquet pollination he obtains excellent fruit set. All the farmers in nearby villages went to Mr Gulab Singh s orchard to investigate his pollination management. They were very impressed and the following year all used bouquet pollination as a short-term solution for polliniser management. It increased fruit yield by about 50%.

2 Unexpected problems 1. Some farmers who do not have enough polliniser trees are stealing polliniser branches from other orchards. There are many cases of such theft. As a result whenever farmers see somebody with scissors, they chase the intruder away. We met one farmer in the Manali Valley carrying a load of blooming polliniser branches. We asked him to stop as we wanted to photograph him with these branches. He was afraid and told us that he brought these branches from his own orchard and was going to hang them in his uncle's orchard. 2. The large-scale use of plastic bags for hanging pollinisers in trees has led to a four-fold increase in the price of plastic bags! LACK OF POLLINATORS Lack of pollinating insects due to the heavy use of insecticides over the past decades is another factor. Farmers have been spraying pesticides eight to ten times each season including the blooming period of apple trees. Bees, butterflies, and moths on apple flowers have all disappeared. Hiring honeybees for pollination Insect pollinators are still needed to transfer the pollen grains from the polliniser to the main variety. For this purpose farmers are renting honeybees (Apis cerana and Apis mellifera). The Department of Horticulture rents Apis mellifera colonies at the rate of Rs250 per colony, (Rs200 as security and Rs50 as rent). Private beekeepers charge Rs800 (Rs500 as security, and Rs300 as rent). Honeybees for rent The number of bee colonies available for rent from the Department of Horticulture is low and the demand for bees is very high. Therefore, to provide bee colonies for a number of farmers, very weak colonies are offered, with only one or two frames covered with bees. Some commercial beekeepers migrate their bees to the Indian plains during winter until June. They are not interested to bring their bees back earlier for apple pollination because they obtain abundant honey from berseem and sunflower in the plains. These crops bloom for long periods and produce much more nectar than apple. The beekeepers earn much better money from the sale of honey, than by renting bees for apple pollination. Now these beekeepers are being encouraged to rent their bees for pollination by increased rental fees. Farmers are ready to pay any price for hiring bees: some farmers hire Apis cerana in log hives at the rate of Rs300 per colony. The State Government is making efforts to encourage farmers to keep their own bees for pollination and has created the Beekeeping Development Office (BKDO), within the Department of Horticulture. BKDO sells an Apis mellifera bee colony at the highly subsidised rate of just Rs300: the market price is over Rs2000. Dr YS Parmar University of Horticulture and Forestry also provides bee colonies free of charge to apple farmers and offers training on how to use bees for pollination. In Kullu District, there is only one commercial beekeeping farm, Yama Bee Farms, renting Apis mellifera for pollination. In Shimla there are more commercial beekeepers who rent out bees for apple pollination.

3 Need for training apple growers to manage bees Farmers have a great awareness of the role of honeybees in pollination, but they have no knowledge of bee behaviour. They want to keep bees at any cost: a farmer stole a honeybee colony from a neighbour one night and kept it in his orchard in the hope that the bees would pollinate his apples during the night. Early in the morning, he put the bee colony back in the owner's orchard! Use of pesticides Farmers would spray chemicals even if there is no disease to prevent the outbreak of apple scab and red apple mites. They are now aware of the harmful impact of insecticides on natural pollinators, and have reduced pesticide application from ten, to five or six sprays a year, usually using the least toxic chemicals. They spray pesticides when insect pollinators are not present - a week before or after apple flowering. Some large-scale farmers are controlling apple pests through biological pest control - rearing various predator insects against the pests. Hand pollination Some farmers in Shimla District are very progressive and are hand pollinating their apples to ensure the flowers are adequately pollinated. According to them this is most important to ensure the quality and yield of apple. They can afford to hire labour for hand pollination of their orchards. Anthers are picked from the flower of the polliniser variety at the balloon stage (partially open flowers) and dried at 22 C overnight to release the pollen grains. These are mixed up with a little white flour or skimmed milk powder and applied to flowers of the main variety (within two days of flowers opening) with the help of a brush. Between 20 and 50 flowers are hand pollinated on one branch and then honeybees transfer this pollen to other flowers of the branch. The role of honeybees is crucial in apple pollination, both in hand pollination of the crop and polliniser management, either by grafting, or hanging pollinisers on the main varieties. CLIMATE CHANGE Climate change during the past eight years has played a critical role in apple pollination failure. There are rains during the flowering season which affect pollination by wind and insects. Low temperatures also adversely affect fruit set in apple. Temperature management If there is a possibility of frost the farmers collect grasses and burn them in the orchards to raise the temperature by a few degrees. Some farmers in Shimla District spray the orchard with pure water at midnight to avoid frost the following morning. Farmers also spray chemicals such as borax, TSO or some alternative insecticides on a limited scale to delay flowering by about one week to prevent flowering when the temperature is very low. To date the farmers have no remedy to prevent rain during apple flowering! CONCLUSION Apple farmers in Himachal Pradesh are now well aware of the need for pollination and are making all possible efforts to ensure pollination occurs: managing pollinisers and pollinators, and opting for strategies to avoid the effects of low temperatures or frost on pollination and fruit set. Government institutions in the State have an explicit mandate to educate the apple farmers on how to achieve good yields, but they have limited resources to cope with the large-scale extension needed in this area.

4 Acknowledgements The author wishes to express sincere gratitude to Dr Harish K Sharma, Dr K C Thakur, Dr R Kumar, Dr Neelima R Kumar, Professor D R Gautam, and Professor L R Verma. The author is also thankful to the farmers of Kullu and Shimla Districts. Financial assistance from the Federal Chancellery of Austria through Austroprojekt to carry out this study is acknowledged. This research was undertaken in Kullu and Shimla Districts during April Over 50 farmers were interviewed and completed questionnaires. 1 $US = Rs40 PHOTOGRAPHS UMA PARTAP Bouquet pollination : a short-term solution which provides pollen immediately Farmers in Shimla District believe hand pollination is the most reliable method The number of bee colonies used for pollination is too small

5 Grafted polliniser branch which will take at least two years to produce flowers