Activity of Corn Silk at Different Days after Silk Emergence

This study was carried out to evaluate the changes in silk activity of two corn cultivars Xundan 518 and Yongyou 618 after silk emergence. Artificial pollination was conducted at different days after silk emergence, and the ear length, ear diameter, barren tip length, 100-grain weight, grain number per ear and grain weight per ear were measured at harvest. The results showed that with the delay of pollination, the number and weight of grains per ear increased at first, peaked at D2 to D4, and decreased subsequently; ear diameter and 100-grain weight showed a downward trend. Correlation analysis revealed that grain number per ear and grain weight per ear were most closely correlated. Rapid silk extrusion and long-lasting silk activity proved that the two corn cultivars Xundan 518 and Yongyou 618 are tolerant to high temperature.