Relationship of N Deposition to Grain Yield and N Response of Three Maize Hybrids¹

Abstract

Three maize (Zea mays L.) hybrids were evaluated for their grain yield under different levels of spring‐applied anhydrous ammonia fertilizer. The N content in the vegetative tissues and grain was analyzed at the midsilk stage and at 60 days after pollination. Of the three hybrids tested, B14 ✕ Oh43 (intermediate type) responded to moderate levels of N fertility, B73 ✕ Mol7 (high‐fertility type) had a great response to additional N, and Pioneer 3732 (low‐fertility type) performed well under low levels of N fertilizer but reached maximum yield with only 67 kg N/ha. There are at least three factors affecting grain yield which distinguish the high‐fertility from low‐fertility type hybrids. These include 1) ability to absorb additional N fertilizer after the midsilk stage, 2) rate and duration of grain fill, and 3) rate of zein synthesis (kernel N sink) affected by N fertilizer. When the kernel genotpye of Pioneer 3732 was modified by pollinating with pollen from B73 ✕ Mol7, the developing F1 kernels not only had grain protein concentration higher than Pioneer 3732 F2 kernels but had dry matter accumulation kinetics complementary to Pioneer 3732 and B73 ✕ Mol7. This complementation resulted in larger kernels than those obtained with selfed kernels of either hybrid. This result indicates the kernel sink is more important than the vegetative source in affecting kernel weight and grain yield.

Cross-pollination effects on maize (Zea mays L.) hybrid yields

“…In an unreplicated trial, Tsai et al (1984) reported that Pioneer 3732with B73 x MolT pollen maintained a higher rate of biomass accumulation in the kernel, delayed physiological maturity, and increased kernel yield (20%) andkernel protein concentration, than when self-or sib-pollinated. In a replicated experiment over2 yr with these two hybrids, Tsai and Tsai (1990) In 1990, an attempt was also made to duplicate the unreplicated PM harvest published by Tsai et al (1984) (Tsai et al 1984;Tsai and Tsai 1990) was not found, nor was any increase in yield of the earliest maturing hybrid (Lx2) by pollen of the later maturing hybrids (Table 5).…”

“…In a replicated experiment over2 yr with these two hybrids, Tsai and Tsai (1990) In 1990, an attempt was also made to duplicate the unreplicated PM harvest published by Tsai et al (1984) (Tsai et al 1984;Tsai and Tsai 1990) was not found, nor was any increase in yield of the earliest maturing hybrid (Lx2) by pollen of the later maturing hybrids (Table 5).…”

“…A population of 60 200 plants ha-' was established in this study, typical of that currently used in the Corn Belt (Lamkey and Smith 1987), whereas Tsai et al (1984) and Tsai and Tsai (1990) to-plant competition. Russell (1984) and Carlone and Russell (1987) have shown that a large portion of the yield gain for maize hybrids ofthe 1980 era resulted from supertor performance at higher plant densities.…”

Direct and Residual Effects of Different Poultry Compost and NPK Fertilizer Applications on Drought-Tolerant Maize Production

“…According to Ayoade (2011), drought is a major factor responsible for crop production and productivity decline in the temperate and tropical regions of the world. The use of drought-tolerant maize cultivars with high yielding potential to cope with the present climate change scenarios (Schittenhelm and Schroetter, 2014) is therefore important since access to drought-tolerant maize variety may be the only alternative mitigating option available to resource-poor African farmers (Tsai et al, 1984).…”

Nitrogen uptake and redistribution during maturation of maize hybrids

“…Hybrid variations in the percentage of final N taken up by the mid-silk stage may range from 40% to 100% (Hanway 1962 Our earlier studies indicate that maize hybrids grown in the Cornbelt may be grouped into three categories. They include: (1) low N-response hybrids which require a relatively small amount of N fertiliser to reach maximum yield potential, and (2) intermediate and (3) high N-responsive hybrids which respond to moderate and large amounts of N, respectively, for higher yield potentials (Tsai C Y et al 1984). Other workers have found little difference in the N requirement for maximum yield of different maize hybrids (Bundy and Carter 1988; Gardner et a1 1990); however, it is not clear whether suppressive environments for high yield, high residual soil N, or a combination of both might account for the differences observed.…”