The Application of Early-maturing Corn to Cropping System of Forrage Crop I. The late-sowing adaptability of corn varieties requiring the short period to maturing

조숙 옥수수에 의한 사료작물 작부체계 구성 I. 조숙 옥수수 품종의 만파적응성

For the constitution of forage cropping system including the double-cropping of corn, attention has been directed towards the early and short maturing varieties of corn such as Comet 80, Comet 85 and Linda as a component forage crop of forage cropping system. Four corn varieties, Comet 80, Comet 85, Linda and Suwon 19 were planted delayedly by each of 45, 55 and 65 days from the recommended sowing date of suwon 19. Under these condition, growth characteristics and late-sowing adaptability of 4 corn varieties were investigated, and the results are summarized as follows; 1. The variety of suwon 19 did not reach the stage of silking in the occasion of late sowing by 50 days from the optimum sowing time for mono cropping of suwon 19. However early varieties such as Comet 80, Comet 85 and Linda silked under the condition of 65 days-delayed sowing from the recommended sowing time of Suwon 19 for mono-cropping. 2. Early varieties of Comet 80, Comet 85 and Linda were so grown by approximately 92% in plant height, 66% in ear height, 88% in stem diameter and 81% in leaf number respectively compared to Suwon 19 at each of three delayed sowing time that exhibited the dwarfish appearance of canopy. 3. Days from sowing to silking decreased as the sowing time was delayed and the average days from sowing to silking in the sowing treatments of 55 days-delayed of Suwon 19, Comet 80, Comet 85 and Linda were 61, 46, 47 and 51 days, respectively. 4. The size of variations of plant height and ear height influenced by delayed-sowing time was comparatively larger in the varieties of Suwon 19 and Linda than in those of Comet 80 and Comet 85. 5. As sowing time was delayed from the optimum sowing time of Suwon 19 for mono-cropping, ear content decreased from 0% of Suwon 19 at 55 day-delayed sowing treatment to 3540% of Comet 80 and Comet 85 at 65 days-delayed sowing treatment.