February 4, 2002	Monday	Ziqa’ad 20, 1422

AN INFORMAL survey was carried out about the citrus production system during which open-ended interviews were held for each category of citrus, Sampling-frame was prepared and interviews were recorded in which 125 citrus growers replied to questions.

During the survey, it was learnt that there was a lack of information among growers in respect of propagation of methods, planting material, varieties, farm-yard manure, fertilizer, insects, pests and diseases. An attempt has been made here to present the relevant information briefly in these regards.

Planting: Swingle has classified the genus citrus into three independent genera: citrus,poncirus and fortunella. He put 16 species under citrus, four under fortunella and one species under poncirus. These three genera can be distinguished in general from each other by their leaf and ovary characteristics. The important factors in planting material such as, genetic characteristics, growing conditions, pre-harvest environment and time of harvesting have great impact on post-harvest longevity of fresh fruits. The genetically improved planting material, when grown under ideal conditions and harvested at optimum stage of maturity can be kept for a longer period.

Methods: Citrus varieties can be propagated by both sexual and asexual methods. Generally, rootstocks are propagated through seeds and most commercial varieties are propagated by various asexual methods.

With the help of seed: Choice of best root-stock is very important because it affects productivity, quality and precocity of the scion trees. Most seeds are polyembryonic and produce seedlings true to type nursery. Fruit seed extraction is taken from vigorous tree by the first week of September and seeds are sown in September or in February-March. Sowing earlier or later affects germination adversely, as such early or late sowing rate should be increased. Around 70-80 per cent of rough lemon seeds germinates. Temperature is the main factor that affects the germination but maturity of seed, species, soil conditions and method of sowing also affects seed germination. Seeds are sown on well-manured and well-prepared and raised seed beds located in a warm place in well-drained soil.

Seedlings should be protected from frost if sown in September and from heat if sown in February-March. These seedlings are ready for transplanting in 6-12 months. Transplanting of seedlings should be done in September-October or in February-March.

Budding: Budding is a method of asexual propagation in which only one bud is removed from the scion variety and is inserted by a special technique in the stock seedling. Budding may be done any time during spring (Feb- March) and autumn (Aug-Oct) when the bark slips freely or when both the stock and scion plants show active growth. The bud should be selected from a healthy and productive tree. The buds will unite