Table 7.
Effect of plant density on crop speed breeding.
| Plant species | Density of plant populations | Other experimental details | Influence on speed breeding generations | Reference | |
|---|---|---|---|---|---|
| Effects | Generations/year | ||||
| Bean (Phaseolus vulgaris L.) |
Planting densities (10*30 cm, 20*30 cm, 30*30 cm, 40*30 cm, 50*30 cm, 60*30 cm) | 8 h·d−1 photoperiod, 150 µmol·m−2·s−1, 70% relative humidity, 21°C | Planting density of 20*30 cm results in the highest yields compared to other planting densities. Greater availability of fertilizers per plant due to low plant density results in more vigorous vegetative growth and late flowering. | Not available | Abubaker, 2008 |
| Cowpea (Vigna unguiculata L. cv. “Walp”) |
High plant density: row-to-row spacing of 60 cm, and plant-to-plant distance of 20 cm. Low plant density: row-to-row spacing of 90 cm, and plant-to-plant distance of 40 cm |
Not available | The earliest flowering date was observed in high-density cropping that improved symbiotic nitrogen fixation by root nodules in cowpea. | Not available | Makoi et al., 2009 |
| Spotted bean (Phaseolus vulgaris L.) |
15, 25, 35, and 45 plants/m2 | Not available | The maximum grain yield was related to the density of 45 plants/m2 while the minimum yield was in the density of 25 plants/m2; grain yield increased with plant density increasing might be attributed to sub branches, which are placed at the lower part of the plant, exerting obvious influence on biological yield increase. | Not available | Biosci et al., 2013 |
| Rice (Oryza sativa L.) |
5 cm × 5 cm spacing (over 4,000,000 plants/hectare), 20 cm × 15 cm spacing (300,000 plants/hectare) |
Not available | A high density triggered early flowering, and shortened the growth duration of rice plants compared to the traditional plant density. | Not available | Rahmanet, 2019 |
| Red beans (Phaseolus vulgaris L. cv. Akhtar) |
Row spacing of 5 cm, 10 cm, and 15 cm | Not available | Higher density (row spacing of 5 cm, 66 plants/m2) provides more sufficient leaf area to absorb sunlight efficiently and achieved the highest yield when compared to the row spacing of 10 and 15 cm, whose plant density was 33 and 22 plants/m2, respectively. | Not available | Asemanrafat and Honar, 2023 |