EFFECT OF PLANT GEOMETRY ON GROWTH AND YIELD OF HEIRLOOM CORN CULTIVARS UNDER TABUK CITY CONDITION
The study evaluates the effect of plant geometry on the growth and yield of heirloom corn cultivars (a1-purple corn cultivars, a2-white corn cultivar) under Tabuk City condition. Determine the effect of plant geometry (b1- 50x30, b2-50 x 40, b3 – 60x30, b4 – 60x40 cm), and determine the interaction effect of plant geometry to heirloom corn cultivars. The experiment was laid out using a Randomized Complete Block Design (RCBD) in the Factorial experiment. The experiment result showed no significant difference was noted in terms of days to tassel, plant height, ear height, ear length, ear diameter, and biomass yield. A highly significant response showed in days to silking, days to maturity, and weight of 1000 kernel but effect and interaction were no significant differences. The yield and yield attributes of heirloom corn showed that the white corn cultivar produced the highest yield (kg/ha) with 7,030 kg and purple has 3,401 kg under plant geometry. Heirloom corn cultivars from plant spacing of 50 x 40 cm produced the highest yield (kg/ha) with 5,912 kg followed 60 x 30 cm, 50 x 30 cm and 60 x 40 cm with a mean of 5,557 kg, 4,956 kg and 4,437 kg. Interaction among the two factors showed highly significant results where white corn is far from yield attributes to purple corn cultivar. From this study, it may conclude that the adoption of 60 x 30 cm plant spacing is recommended for heirloom white corn cultivars since it produced highly significant results. For better yield for heirloom purple corn it is suggest to adopt 50 x 30 cm plant spacing. The research suggests more studies on plant spacing to determine its effect on the growth and yield of heirloom corn cultivars.