Origin and distribution
The kiwi fruit is native to China and has originated in the mountain ranges of south western China. It belongs to the family Actinidiaceae and known by various other names viz. kiwi berry, Chinese gooseberry, Mihoutao, Yangtao and grosella. It spread to Japan, Russia, Europe, USA and New Zealand in the beginning of 19th century and now grown at large scale in these countries including others like Iran, South Africa and Australia.
In India, kiwi fruit was introduced as an ornamental vine in 1960’s at Bangalore but could not perform well due to hot climate. Later in 1962, NBPGR introduced Allison variety from the USA and planted at its regional station Shimla.
Looking at its good performance and potential and new fruit more varieties were introduced from New Zealand. The material was established at Shimla and a large number of experiments on its propagation and production were conducted. Now kiwi is one of the major fruit crops in Himalayan region including north eastern states of Arunachal Pradesh, Sikkim and Meghalaya. There are only one wild species of Actindia i.e. A. callosa Lindl. var. callosa occurring in the Arunchal Pradesh and parts of Sikkim.
The plants are tiny, have large broad leaves and dioecious in nature, thus need a male plant as a pollinizer. It requires around 700 chilling hours with a temperature below 70C to break the dormancy of the buds. Kiwi vines attain full vegetative growth after 2 years but bear fruits 3rd year onwards. The flowers are borne in the axil of basal as four or five lateral buds on current season’s growth. Reproductive phase of kiwifruit is about thirty weeks starting from March to October. The fruits are oval with stiff hairs on the skin which is brown in colour and green inside.
Nutritional value and uses
Kiwi fruit is perhaps the best in terms of its nutritional quality amongst soft fruits. It is rich in vitamins and mineral and has proven antioxidant activities. Fresh fruits are consumed directly once they become soft. The seeds are used in making pastries, the fragrant flower in producing perfume, and leaves being rich in starch protein and vitamin C used as pig feed. Fresh fruits are combined with other fruits used to prepare salad and desserts and also in ice-cream, sherbet, jam and jelly
Kiwi farming cultural practices
Kiwi fruit grows well in sub-temperate, warm and humid climatic conditions at an altitude varying from 1200-18000 m while few varieties like Hayward may perform well up to 2000 m. It requires well drained sandy loam soil having good water holding capacity. Plants can be propagated by cuttings, grafting and budding, but cutting has proven to be the most rapid and suitable method of propagation. The cuttings of 0.5-1.0 cm thick with relatively short internodes and 15- 30 cm long are ideal.
Before planting in the nursery beds, cuttings should be treated with rooting hormone IBA having 3000 ppm concentration for 10 seconds. The rooting medium consist of FYM: sand: leaf compost: soil in the ratio of 1:1:1:1 has given highest rooting percentage in the mist chamber under controlled conditions. The success rate is low under open conditions, which, however, can be increased if the nursery bed is properly thatched or shaded with a shaded net. The cuttings should be placed in the wooden tray or nursery bed at a distance 8-10 cm for rows and plants apart. It is important to ensure sufficient moisture in the nursery particularly in the initial month i.e. March to June.
Generally, kiwi vines are planted at 5×5 m distance, however, the distance may vary from variety and system of training used. By and large, it is T-bar and Paragola systems, which are preferred for planting and training of kiwi vines. It has been found that we can accommodate a number of plants in T-bar than Paragola system without sacrificing yield and quality of fruits. The vines are planted in the field after the fall in February but utmost care should be taken to ensure the ratio of female: male which is normally 4-5:1 depending upon the topography of the orchard. It is mentioned here that pollen load play a greater role in the setting of more number of fruits and size of the fruit. It can further be enhanced the keeping bee colonies in the orchard.
Pruning of the vines during winters (in peak winters i.e. January) also contribute a lot to enhancing the productivity, because vines grow so much that they become overcrowded and unmanageable. It should be done in such a way that plenty of fruiting branches, which are generally one year old, are available to bear fruits. Further, the vines should not be pruned if the weather becomes warm because it starts bleeding from the cut points, which results into drying of vines.
The nutrients requirement of kiwi vines can be met externally by applying FYM and NPK in the ratio of 20 kg FYM and 500 g mixture of NPK per vine each year in winters. Kiwi fruit plant has shallow root system and due to vigorous vegetative growth, leaf size, it requires irrigation particularly during summer. The fruits mature in October-November but have hairs on the fruit surface which can be removed shaking the fruits in the jute bags. The fruits can be stored up to 4-6 weeks at ambient temperature and 4-6 months in cold storage at -0.60 to 0.0oC.
Presently, genetic resources of kiwi that are being maintained and widely cultivated in India include five pistillate varieties viz. Allison, Bruno, Hayward, Monty, Abbott and two stamintae varieties Allison and TomuriOther species such as A. arguta has also been characterised. It has small, glabrous fruits come in clusters. The average fruit weight was 9.20 g and TSS 19%. Other species of kiwifruit viz. arguta, A. polygama, A. callosa, A. arguta var. purpurea are found in China while A. callosa Lindl. var. callosa also occur in the Arunachal Pradesh and parts of Sikkim bordering China. It is mentioned that all the varieties available in India are green fleshed but yellow fleshed and red fleshed kiwi varieties has also been developed. Other commercial varieties include Zespri Gold, Greensill, Chiko, Saanichton-12, Hong Yang, Enza Red.
- National Bureau of Plant Genetic Resources Regional Station Phagli, Shimla