TROPICAL & SUB-TROPICAL FRUITS

Limes and Lemons

Lime or Acid lime (Citrus aurantifolia swing). Is more popular in India than lemon (Citrus limon). Acid lime is cultivated largely in Andhra Pradesh, Maharashtra, Tamil Nadu, Gujarat, Rajasthan, Bihar and to a limited extent in other states.

Lemons are grown only to a limited extent in homestead gardens. Limes are available throughout the year in some part or the other in our country. They are used as fresh fruit or for the preparation of pickles and beverages. They are rich in vitamin C, minerals and salts.

Climate: Areas with dry climate and low rainfall are best suited for growing limes. Lemons can be grown in heavy rainfall humid regions.

Soil: Lime and Lemon may be planted in medium black, loamy or alluvial soils having perfect drainage and devoid of calcium carbonate layer.

Varieties: Commonly grown acid lime cultivar is Kargzi lime, but recently identified four high yielding cultivars Vikram, Prumalini, PKM, and Sai Sharbati are now gaining popularity. Commonly grown lemon varieties are Assam lemon, Italian lemon, Pant lemon, Galgal and Eureka lemon, Sevilla and Malta lemon varieties are popular in South India.

Propagation: Acid lime can be propagated by seed, budding or air layer. Since it is highly polyembryonic, seedlings are true to type and resistant to diseases. Propagation by seedling is recommended. Budded plants on Jambheri or Gajanimma are used for planting lemons.

Planting: Pits of box 60 x 60 cm size are dug 5 to 6 meters apart each way and filled with 30 to 40 kg. Farm yard Manure or compost and Top soil along with 2 kg superphosphate. One year old, healthy seedlings of recommend acid lime variety of bud grafts of choice lemon variety is used for planting. Most ideal season for planting is the onset of monsoon (June - July) for both time and lemon. However, in heavy rainfall area September-October would be appropriate planting season.

Interculture: Low growing vegetables, leguminous or green manure crops may be grown as inter crops between young trees upto 4 to 5 years of their age. Area around plants may be kept weed free by weeding and hoeing regularly.

Care of young Orchids: Soon after planting plants be supported with bamboo stick and irrigated thoroughly. Main stem of the young sapling be topped at a height of about one meter from ground level within 25-30 cm from cut end 3-4 well spaced branches be allowed to grow in different directions to form main limbs of the tree. Plants be protected against pests and diseases by spraying with pesticides and fungicides regularly.

Special Horticultural Practices: Acid lime flowers and produces fruits almost all the year round, but there are three major flushes in June-July, September-October and January - February. These are known as Mrig Bahar, Hast Bahar and Ambia Bahar respectively. Fruits of September-October (Hast Bahar) flowering harvested during summer months are most remunerative. To achieve this, irrigation be suspended for 1 to 11/2 months before actual flowering. During this period field may be cultivated and applied with manure and fertiliser towards the end and irrigation be resumed. Plants be sprayed with 1000 ppm cycocil twice during September-October which has been found to increase the fruit yield two times than the normal yield.

Nutrition: For each completed year of growth till 5 years, 20 kg Farm Yard Manure, 100 g urea and 1 kg Superphosphate be applied per plant in two equal split doses in June and December every year. Fifth year onwards application of 40 kg FYM, 400 g N + 200 g P + 400 g K per plant in two split doses in June-July and September-October be applied. In addition, 150 g N be applied per plant 15 days after fruit set. Manures and fertilizers are applied in a circular trench 20-30 cm deep about a meter wide around the periphery of the tree. Manures are thoroughly mixed with soil, and the tree irrigated profusely.

Irrigation: Young plantation needs regular watering during post-monsoon period at an interval of 10-15 days and at 8-10 days during summer months. Water is applied around the periphery of the tree in a ring and basin system so that tree trunk should not come in direct contact with water. The irrigation is suspended for 1 to 11/2 months during Bahar treatment. It is resumed during flowering. Bearing trees should get regular watering at 10-15 days during summer and 15-20 days interval watering at 10-15 days during summer and 15-20 days interval during winter.

Plant protection:

The major pests affecting the Acid lime and lemon plants include Lemon butterfly, leaf eating caterpillars, whitefly, leaf miner and mealy bugs. These pests can be controlled by spraying with Monocrophos, Endosulphon or Phosphamidon 1.5 to 2 ml.per litre of water at an interval of 10-15 days. Instead of repeating the same pesticide different pesticide be used at each spray.

Among the diseases Gummosis and canker are very devastating. For control of Gummosis, use ring and basin system of irrigation to avoid contact of water with main stem so that the disease causing soil borne fungus will not attack the stem. If disease is seen remove the affected portion of bark and 1 cm of surrounding healthy bark with knife and apply Bordeaux paste (one part copper sulphate plus one part quick lime and sufficient water to make paste) thoroughly on the wound.

Canker is caused due to bacterial (xanthomonas sp.) infection, which develops considerably during rainy season. It appears as a minute yellowish-brown spots on stem, leaves and fruits which turn into corky brown specks. Affected leaves turn yellow and drop down. Remove all the affected parts and fallen leaves and burn them. Spray the trees with Bordeaux mixture 3:3:50 by using 1.5 kg copper sulphate plus 1.5 kg quick lime in 225 litres of water or 1250 gm of copper oxychloride in 500 litres of water also can be sprayed. Repeat, if necessary at an interval of 10-15 days.

Harvesting and yield: Maturity of citrus fruits depends upon the climatic conditions, nutrition, heat units and moisture availability. The period of maturity is shorter in acid lime (5-6 months) and longest in mandarin and sweet orange. The lime and lemon fruits are harvested when they just start changing. They are harvested in installments as they ripen. Major harvesting period in July-September and November-January.

Post harvest handling and Marketing: Harvested fruits are graded according to size and colour and packed in bamboo baskets or wooden crates lined with neem foliage. Sometimes fruits are packed in gunny bags and transported by rail or road to distant markets.

Ag.
Technologies
(Horticulture)