MAIZE: METHOD OF SOWING & IMPORTANCE OF THINING AND GAP FILLING

Maize (Zea mays) is the most important cereals crops after wheat and rice which belongs to family Poaceae. It is recognized as the “Queen of cereals” crops because of its demand and widely acceptability .Maize is the second stable food crop of hilly region of Nepal more than 80 %crop grown in the hills (70% in mid hill and 10 % in high hill). Three purpose of maize cultivation is as human food, feed for poultry and livestock. Maize has significant quantities of vitamin A, nicotinic acid, riboflavin and vitamin E. Maize plants are erect and height varies from 1.5 to 3m according to varieties. The cultivation time of maize varies from place to place due to different in climatic condition .Maize is day neutral plant so can be grown in three season. The current maize growing area of Nepal requires 17508 MT of seed rate at 20 kg/ha but the seed replacement rate is very low. Maize contribute 3% to national GDP and 7 % to AGDP ( FAO 2009).There is great scope for increasing maize production in Nepal if proper quality seeds and improved cultivation techniques are applied.

SEEED RATE: Maize is non-telling crops it can’t compensate for lost space so it should be maintain in such a way that final plant population will between 60 to 70 thousand per hectare.

SEED SELECTION AND TREATMENT: Seed should be selected based on the length of growing season and availability of optimum moisture regime. If the farmer wants to use their local product germination test should be done.

METHOD OF SOWING MAIZE

Method of sowing plays important roles in the establishment of crops. For the better crop production it requires suitable soil condition which can be obtained by best tillage operation and sowing method .Appropriate sowing method has various advantages like better intercultural activities, uniform irrigation, and management of insects, disease and pest. Maize is sown by different method of tillage operation and establishment. There are some of the methods of sowing maize describe as:

BROADCASTING: Broadcasting is the process of random scattering of seeds on the surface of seedbeds. It is mainly found in Terai and inner Terai region. It is done both manually and mechanically. In manual broadcasting uniformity of seed depends upon skill of the man. After seed broadcasted it is covered by doing tillage at shallow depth by the local plough cultivar planking. In this method there is difficult in performing in intercultural operation.

Sowing behind the plough: It is very common method used in village. A man drops the maize seeds in the furrow behind the plough .It can be done by device known as malobansa. It consist of wooden hopper attached to hallow bamboo attached with local plough .A man drops the seeds through the funnel and other man handles the plough and bull locks . This method is slow and laborious.

Dibbing: Dibbing is the process of placing seed in holes made in seed bed and covering them. The instrument used for dribbling the maize are dibbler, jab planter, push planter. This is very time consuming process which is suitable for small scale farming. Seed rate is less compare to other.

Drilling: Dropping the seeds in furrow lines in a continuous flow and covering them with soil is done in drilling method. It is done by seed drill machine and maize planter under conventional tillage, minimum tillage or zero tillage.

Bed planting: On non –uniform lands this method is most suitable for successful cultivation of maize crop. In this method machine prepared bed at uniform spacing (generally 60 cm). Sow seed at central row of bed and cover seed with soil simultaneously in a single pass of machine. Under temporary excess soil moisture due to the heavy rain, the furrows will act as drainage channels and crop can be saved from excess soil moisture. Irrigation water can be saved to tune of 20 -30 %.

INTERCULTURAL OPERATIONS IN MAIZE

Successful crop production mainly depends upon the cultural and intercultural operation. Different types of intercultural operation are performed during the growth of maize plant like weeding, earthing up, thinning and gap filling detasseling, leaf stripping which makes the growth and development of plant in effective way.

THINNING AND GAP FILLING

Higher or lesser plant both hamper in the productivity of the maize. Thinning is done when there is dense plant population. It is mostly done in broadcasting method of sowing at seedling stage 15 to 20 days. Thinning out is also done between tasseling and silking stage if there is failure in tasseling and silking in maize plant. High plant population in maize field reduces in crop yield due to intra crop competition. Plant may suffer from shortage of space, light, air moisture for individual crop plant and fall to grow as productive. Thinning means practice of keeping only one healthy plant removing another plant from each spot. After sowing several frungivorous and granivorous animals and birds feed on many seeds and some seed fail to established them in new environment and dies. It may cause low germination rate. Some of the area may contain empty space. In case of missing spot found the transplantation should be done after enough watering.

IMPORTANCE OF THINNING AND GAP FILLING

1) Thinning and gap filling maintain uniform plant population throughout the maize field.

2) Thinning helps to control competition for nutrition, water, sunlight as a result plant developed well.

3) If the plants don’t have plenty of air circulation they may be attacked by the disease. Thinning and gap filling plant can replace the diseased plant with healthy.

4) Less plant means less production. So empty spacing can be filled by transplanting new plant.

Thinning plant is not very easy but it must be done. Farmer feel difficult to thinning out the plant but a poor harvest will be more devastating than killing a few now. Both thinning and gap filling ensure ideal plant population and best utilization of sunlight, space, nutrient moisture etc. which ultimately increase yield.

Writer: Rakshya Gyawali (Student, Bsc. Ag IAAS Paklihawa Campus)