Growth and yield of highland maize in Mexico

Abstract

The growth and yield of five highland varieties of tropical maize were studied. Grain yields were between 4-7 and 8-8 t/ha. Crop growth rates (C) increased to a maximum of between 25 and 35 g/m 2 /day at silking and then declined. Grain growth rates (maximum 21 g/m 2 /day) exceeded current C during most of the grain-filling period.After silking, when C exceeded grain growth rate, dry matter accumulated in the stem and husk, resulting in an increase of from 200 to 600 g/m 2 . Later, as grain growth rate increased and exceeded current C, some of this accumulated material was incorporated into the grain, and stem weight decreased. A comparison of the dry weight changes after flowering in these varieties with those reported for a hybrid that yielded 12 t grain/ha indicates that the smaller yield of the Mexican varieties was associated with smaller grain growth rates and the incorporation into the grain of a smaller fraction of the dry weight produced after flowering. These results suggest that the capacity of the grain 'sink' to utilize assimilates limited yields in the tropical varieties.

Effect of plant density and detopping following silking on cob growth, fodder and grain yield of maize (Zea mays)

“…is > 2-5, the additional DM produced is stored in the By using short-statured plants or by lowering stem. Goldsworthy & Colegrove (1974) reported plant height mechanically from 2-8 to 1-8 m and by mobilization of stored reserves during the linear keeping plant population density between 48000 and phase of grain growth of maize. Langer (1979) also 65000/ha, a 66 % increase in grain yield was achieved mentioned that maize as well as other cereals possesses more than enough photosynthetic capability and thus * Present address: Agronomy Division, BARI, the surplus photosynthate is stored in the form of Joydebpur, Gazipur 1701, Bangladesh.…”

Growth and yield of lowland tropical maize in Mexico

“…The procedure for measurement of leaf area and dry weight was the same as that described in an earlier report of a similar study of highland maize varieties (Goldsworthy & Colegrove, 1974). The methods of analysis used to describe changes in dry weight (W) and leaf area index (L) with time (t) were also the same as those described in the earlier paper.…”

Source-sink relationships in maize grown in a cool-temperate area

“…Among grain crops, the sourcesink relationships have been studied more extensively in wheat and barley (Tollenaar, 1977). Some authors have reported that grain yield was limited by the sink capacity (Bingham, 1967;Evans and Rawson, 1970); others have concluded that yield was limited by the source (Welbank et al, 1966;Simpson, 1968), whereas Fischer (1975) and Stoy (1976) (Yamaguchi, 1974;Goldsworthy and Coleogrove, 1974).…”