Cauliflower is a very important nutritious vegetable crop grown in Bangladesh in the winter season. Since it is a very delicious vegetable and there is a good demand of cauliflower due to different categories of recipes can be prepared from this vegetable; it has become a very popular vegetable in Bangladesh in recent years. Cauliflower is relatively a short duration decorative type crop and different types of varieties including extra early, early, mid season and late season varieties of cauliflower are now available in the market. And this is why the vegetable growers showing more interest to grow cauliflower in major part of the year (near about 8 months) in Bangladesh. Extra early season and early season cauliflower varieties are boon to the growers as their curds usually fetches higher price than the seasonal type. However, cauliflower seed production is very rare in Bangladesh though cauliflower seed production is a profitable seed business and huge quantity of seeds is usually imported every year to meet the growing market demand of cauliflower seeds. Naturally the seed price of cauliflower seeds is very high (TK. $ 625 to $ 820 per Kg) and as sufficient information regarding their sowing time, cultivation method of the foreign seeds remains unknown, many grower usually incur losses annually by growing this otherwise profitable crop. But, if it would be possible to produce cauliflower seeds locally in Bangladesh several critical problems regarding cauliflower production could be minimized. Not only that a huge amount of foreign currency could be saved annually which are being drained out every year for purchasing cauliflower
seeds from foreign companies. It can be mentioned here that cool season is very much essential for the production of cauliflower seed and as we have cool and dry season it is possible to produce seeds of cauliflower in Bangladesh locally using suitable variety/varieties and techniques as well. Therefore, an attempt was made to produce cauliflower seeds (early season type) at BRAC Agricultural Research & Development Centre (BARDC) using locally available varieties following curd scooping method in the Rabi season (winter season).
The techniques for the production of cauliflower seeds by this method has been described below:
Step-1: Selection of an early type cauliflower variety. In Bangladesh, for cauliflower seed production the most important criteria are selection of a suitable variety and setting a suitable growing period of the cauliflower targeted for seed production. It has been observed that early bolting type variety ensure good seed production in cauliflower. Naturally in Bangladeshi agro climatic condition a good early season variety is very much suitable for commercial seed
production.
Step-2: Sterilization. All the apparatus to be used for curd scooping i.e. knife; forceps etc. should be clean and have to be sterilized by wiping up these apparatus with rectified spirit. Hands should also be sterilized by the spirit.
Step-3: Selection of curd and removing the central portion of the curd. Morning is the best time for removing the core of the curd. A relatively matured large size half loose curd having the diameter of 18-22 cm (700 gm to 1 Kg; which has already lost the compactness of the curd) will be selected for this purpose (Fig.1). Now the central portion of the curd will have to be removed by cutting the core portion of the curd (2.50-2.75 cm. diameter from the centre) using a sharp knife.
Step-4: Cleaning. After removing the core portion of the curd the wounds will be cleaned gently by a piece of cotton sterilized with rectified spirit (Figs. 2 &3).
Step-5: Protection from fungal infection. In the same day at afternoon ‘Indofil’ or any other ‘Mancojeb’ containing fungicide (1 gm per litre) will have to be sprayed gently over the curd to prevent any damage of the curd due to fungal infection.
Step-6: Nursing. This is a very important step for cauliflower seed production. After removing the core portion of the cauliflower curd proper nursing will have to be provided for each plant through side dressing of chemical fertilizer and organic manure alternatively and supplying light irrigation. It is better to avoid flood irrigation during this stage rather gentle can irrigation should be ensured. At this stage oldest leaves will have to be removed to keep the plant more healthy.
Step-7: Supplementary pollination. At the time of flowering normal cross pollination can be supplemented manually by shaking plants with the hand besides allowing more insects as main pollinator. At this stage the abortive parts of the curd (i.e. the part of the curd which did not produce flower stalks) will be removed carefully by cutting them with sharp knife or blade.
Step-8: Disbudding & Staking. After the production of the desired number of siliqua the terminal part of each of the fruit stalks (peduncles) will be snapped to ensure better growth of the fruits and the seeds within it. At this stage staking will also be provided to the plants with suitable size sticks (Fig.7). Spraying of pesticides following a suitable schedule will keep the plant more healthy which is very much essential for cauliflower seed production as well.
Step-9: Harvesting. After the completion of proper ripening of fruits i.e. when the siliquas will fully ripen and become dry on fruit stalks; these dry fruits will be collected in net bags. After collecting fruits, all the fruits will be dried in the sun for 1-2 days. Finally the seeds will be collected by crumbling the dry fruits. Once the seeds are separated from fruits the properly mature seeds will be dried again for 1-2 days in the sun to keep the moisture level 7- 8% before storage.
Curd scooping is a very good technique for cauliflower seed production. By following this technique 25-30 gm. of good quality seeds from each plant can be produced. High quality healthy seedlings were produced from these seeds in the following year and standard size curds were also harvested from the plants raised from these good quality seeds.