An autotetraploid, Sawonppong 28 was derived from a thick-leaf and highly productive mulberry variety, Huyeoprok, by colchicine solution treatment on growing point and its characteristics were as follows. The number of somatic chromosomes of the derived variety was 2n=56 of an autotetraploid and green tip sprouting stage was medium budding variety with triangular oval shape and thick leaves contained rich chlorophyll. The length of branches was comparatively short and the number of branches was also small. However the branches were thick and non-budding length percentage at basal part of branch was high and cold hardiness was weak.
뽕잎 두께가 비교적 두껍고 수량성이 높은 후엽녹의 생장점에 Colchicine용액 적하처리를 하여 창성한 4배성인 4원뽕 28호의 주요 특성은 다음과 같다. 1. 체세포의 염색체수는 2n=56인 4배체이다. 2. 봄철 발아개엽기는 중생뽕이고 잎모양은 삼각형에 가까운 타원형으로 폭광형이고 잎두께는 매우 두께우며 잎면적당 염록소 함량이 많다. 3.가지길이는 비교적 짧고 가지수도 다소 적으며 가지굵기는 굵은 편이고 기부불발아장비율이 높고 내동성은 약하다.
