The growth and development of pearl millet as affected by plant population uri icon

abstract

  • Pearlmillet (Pennisetum americanum (L.) Leeke) was grown at ICRISAT, Hyderabad, India at 20 densities ranging from 50 000 to 400 000 plants ha?1 using a Nelder fan design. Studies were made on the effect of population on the distribution of plant dry weight, leaf area, grain yield and yield components throughout the season. The first effect of increasing population was evident at panicle initiation (<6% final dry weight produced) where dry weight accumulation in the main axis was unaffected but that in the tillers was reduced. Subsequently, the increased plant population resulted in reductions of 77% in total weight per plant, 66% in leaf area per plant and 59% in tiller number per plant at 50% anthesis. Thedevelopmentof green leaf area per plant followed the same trend over the range of populations, so that leaf area index ranged with increasing population from 2.9 to 6.7 at 50% anthesis; severe leaf senescence occurred in the latter part of grain filling. As population increased, thedevelopmentof tillers terminated earlier in thegrowthofthe plant, resulting in a reduced tiller survival rate and therefore reduced productive head numbers per plant. Grain yield per plant declined owing to the reduced head numbers and also to lower seed numbers per head. Seed size remained largely unchanged. Population influenced plant yield chiefly through the highly responsive yield fraction of tillers, asthe yield ofthe main axis was relatively stable. Grain yield ha?1 increased to a maximum at 150 000 plants ha?1, which was maintained through to 400 000 plants ha?1 due to the large degree of plasticity in productive tiller number per plant

publication date

  • 1985
  • 1985