Evaluation of yield and physiological growth indices of mungbean genotypes to planting date

In order to study the effects of planting date and cultivar on yield, protein percentage and physiological growth indices of Mungbean an experiment was conducted in Agriculture and Natural Resource Research Center of Tehran province in 2011-12. Four mungbean [Vigna radiata (L.) Wilczek] cultivars (‘Parto’, ‘Gohar’, ‘Mehr’ and a promising line ‘NM-94’) were sown at 3 dates with 30 days intervals starting from 21 April to 22 June to identify the suitable variety(s) and optimum sowing date for getting maximum yield of mungbean. The design was a split-plot replicated three times with sowing date as main plots and cultivar as sub-plots. Promising line ‘NM-94’ was ranked first in terms of seed yield (1797.4 kg ha-1) followed in order of ‘Gohar’ (1674.8 kg ha-1). The highest seed yield (1678.2 kg ha-1) was obtained from 22 June sowing date. Delayed sowing caused to decrease of growth period length from 92.9 (for 22 April) to 82.6 (for 22 June) that it resulted to a significant decrease of vegetative growth indices such as plant height and biological yield. The maximum LAI and CGR were obtained at a longer time and had more value for earlier sowing dates. The growth period length decreased for the last sowing date, but early entering to flowering stage increased grain filling portion from total growth period. Sowing date had not a significant effect on protein percentage, but this effect was significant for varieties. ‘NM-94’ line and 22 June were the best choices for south east region of Tehran province.