Effects of Planting Density on Leaf Area and Productivity of Two Maize Cultivars in Nigeria

Abstract

Two maize cvs, FARZ 23 and FARZ 25, were grown at three densities (37,000, 53,000 and 80,000 plants/ha) in 1979 and 1980. Leaf area index (LAI) increased with increase in plant population and was at a maximum at mid-silk. Grain yield was highest at 53,000 plants/ha. There was no relation between LAI and grain yield but there was a positive correlation between LAI and total dry matter yield.Most farmers in the humid tropics grow their crops at wide and random spacings because of the system of cropping, which involves growing two or more crops together. These crops are introduced onto a piece of land at various times, and allowance is usually made for such introductions. However, as management practices improve and more farmers grow their crops sole, specific plant populations are more likely to be used.The situation in the ordinary farmer's plots is made even more complicated by his pattern of sowing 3-5 grains of maize per stand without thinning. Bartlett's (1980) survey of farming practice in the forest zone of Nigeria reported that one-third of farmers used a spacing of about 90 by 90 cm with 2-3 plants per stand; a smaller proportion (24%) reported a modified spacing of 90 by 60 cm; 15% used 75 by 75 cm; and none used the recommended 90 by 30 cm with one plant per stand. Such management practices are bound to affect the crop.The importance of plant density as a factor determining growth and yield of maize has been well established elsewhere (e.g. Ferry and Janick, 1971;Mock and Heghin, 1976;Moll and Kamprath, 1977;Milbourn et al., 1978) but only few reports are available from Nigeria (Fayemi, 1963;Chinwuba, 1967;Egharevba, 1977), where no definite recommendations are at present made. In a few research establishments and Ministries of Agriculture maize is grown at a population of 37,000 plants ha" 1 (90x30 cm), at which spacing improved maize varieties would probably not exploit the factors necessary for growth to the maximum. Hence this study examined the effect of density on growth and yield of maize.

Effects of density of planting and time of nitrogen application on maize varieties in different ecological zones of West Africa

“…The genotypes used in this study did not respondlo density beyond 53,333 plants-ha"' at Ikenne and Mokwa, though a response was obtained up to 79,999 plants-ha' 1 at Kaduna. The results of this study corroborate earlier findings of Remison and Lucas (1982) who recommended a planting density of 53,000 plants-ha-1 for maize production in the forest zone. The response up to 79,999 plants-ha" 1 obtained at Kaduna was similar to those that have been reported in temperate regions (Tollenaar, 1989 and1991).…”

“…The usual planting density in Nigeria, as an example, ranges from 18,000-55,000 plants-ha" 1 (Ebong, 1988). However, new varieties can be planted at higher density between 53,000-68,000 plants-ha' 1 (Remison and Lucas, 1982;Carolene and Russel, 1987). Ebong and Wahua (1991) observed that increasing the maize planting density per unit area of land enhanced the association of grain yield with its major yield components: number of cobs-planf', number of kernels-row 1 , and weight of 100 grains.…”

Growth responses of two varieties of Heliconia flowers to selected growth media in Port Harcourt, South-South Nigeria

“…The number of leaves was determined by counting. The leaf area was determined by multiplying leaf length by leaf width and a constant (0.75) (Remison and Lucas, 1982). Stem height was measured from the base of the plant to the tip of the terminal leaf bud with meter rule.…”

Nitrogen Level and Plant Density Effects on Different Agro-physiological Traits of Maize

“…The suppressive effect of higher density on number of cobs per plant has also been recorded by Putnam at al. (1986) and Ramison and Lucas (1982). Similarly nitrogen deficiency results in less number of cobs per plant of maize (Short at al., 1982).…”