EFFECTS OF WATERING FREQUENCY AND SOIL TYPES ON SEED GERMINATION AND SEEDLING PERFORMANCE OF LESPEDEZA CYRTOBOTRYA AND DIANTHUS BARBATUS

Abstract

This study was carried out to determine the effect of various watering regimes in different soils on seed germination and seedling establishment for two species (Dianthus Barbatus and Lespedeza cyrtobotrya) The ratio of water used for watering was 16ml water/100g soil. Three watering frequencies (i.e. once daily; once every 2 days; once every 3 days) were applied for two soil types (Leaf mold soil and merchantable soil) for a period of 150 days. The differences in seed germination, seedling survival and seedling growth were monitored in all experimental units. A more regular watering frequency increases soil moisture, and vice versa. The results showed that watering frequency had significant effects on seed germination (p=0.008), number of plant leaves (p=0.05), with visible but statistically insignificant effects on mean plant height (p=0.19) and seedling survival (p=0.3) for two plant species. The total height of plant species also varied greatly within treatments. Positive correlations were recorded between germination rate with leaf number (r=0.79, p=0.0001); plant height with survival rate (r=0.65, p=0.001); plant height with leaf number (r=0.77, p=0.0001); survival rate with leaf number (r=0.66, p=0.0001) etc. Seed germination and aboveground heights of D. barbatus and L. cyrtobotrya decreased at the more regular watering frequency of once daily in both soils. On leaf mold soil, the total height and mean height of L. cyrtobotrya decreased with increased water stress at once every 3 days watering frequency. Also, the total height of D. barbatus decreased with increased water stress at once every 3 days watering frequency on this soil, even though its mean height did not decrease. In contrast on merchantable soil, the total height and mean height of L. cyrtobotrya increased with increased water stress at once every 3 days watering frequency, indicating that this plant is more resistant to stress on this soil. Whereas, the total height and mean height of D. barbatus decreased with increased water stress on this soil. On leaf mold soil, once every 2 days watering was the most suitable watering frequency for both species in terms of achieving best seed germination and seedling establishment. In contrast on merchantable soil, once every 3 days watering frequency was most suitable for L. cyrtobotrya, whereas both once every 2 days and once every 3 days watering frequencies were suitable for D. barbatus on this soil. The results suggest that using the required watering frequency and soil type is imperative to ensure sustainability in plant production and seedling establishment.