Abstract
In the current study, we investigated effects of a combination of earthworm casting, environment-friendly by-product fertilizer, and cultivation soil of Gymnocalycium mihanovichii in a heavy fertilizing culture on diameter, height, numbers of tubercles, and chemical properties of soil thereby elucidating optimal mixture ratio for securing production as well as providing nutrients throughout cultivation period. The Gymnocalycium mihanovichii var 'Ihong', one of grafted cactus for export (Rootstock: 9 cm, Scion: $1.5{\times}1.3cm$ grafted cactus) was cultured in plastic houses of Agricultural Technology Center located in Naegok-dong, Seocho-gu, Seoul from June, 2013 through December, 2013. For the control group, a mixture of sand and fertilizer (50:50) was used as this ratio is widely utilized in farmhouses. In contrast, a variety mixtures of sand and earthworm casting that was produced with food wastes was compared; the mixture ratios were 80:20, 60:40, 40:60, 20:80, and 0:100 and pH for these mixtures were found to be similar each other (ranging between 7.1 and 7.4) which is in an appropriate range (pH 6.5-7.5) for cultivation of G. mihanovichii. The organic content was increasing along with increasing contents of earthworm casting ratio while it was lower than the treatment practice group (32-43 mg/kg vs. 55 mg/kg). The content of exchangeable cation was also increasing as the ratio of earthworm casting was elevated; although levels of $K^+$, $Na^+$, and $Mg^{2+}$ were lower than the treatment practice group, the level of $Ca^{2+}$ was higher ($9.1cmol^+/kg$ and $11.5-33.7cmol^+/kg$ in the treatment practice group and the earthworm casting group, respectively). Three months after grafting, diameters of G. mihanovichii were compared with the control group; consequently, there was a significant difference noted in between the earthworm casting group and the control group (31.39 mm vs. 32.46-37.59 mm). After 5 months, growth characteristics of G. mihanovichii were evaluated. Similarly, the diameter of G. mihanovichii was significantly increasing in the group with higher ratio of earthworm casting treatment (32.63 mm vs. 32.49-37.59 mm). The height of tubercles was 2.63 mm in the control group while it was significantly elevating along with the ratio of earthworm casting mixture. The more numbers of tubercles, the more incomes for farm-houses; as results, higher mixture ration of earthworm casting resulted more numbers of tubercles compared to the control group (2.7 vs. 3.2-8.3 ea). In particular, in the earthworm casting groups with 80% and 100% ratios, the numbers of tubercles were 6.2 and 8.3 ea, respectively, which is 2.5 times more than those of the control group. These results indicate that earthworm casting treatment may be utilized in G. mihanovichii farming houses for short term production of tubercles. In the group with 40% and 60% of earthworm casting mixture, the numbers of tubercles were found to be 4.5 and 4.8 ea, respectively which is higher than the control group as well; in these groups, there were no issues with soil drainage as well as moss formation. Given the analysis results of growth characteristics of G. mihanovichii, it was concluded that 40% and 60% of earthworm casting mixture might be the optimal ratios.
본 연구는 다비 재배를 하고 있는 비모란선인장 재배토양에 친환경 부산물비료인 지렁이분변토를 혼합 재배할 때 구경, 구고, 자구수 및 토양 화학적 특성에 미치는 영향을 조사하여, 재배기간 동안 충분한 영양을 공급할 수 있고 생산량을 확보할 수 있는 적정 혼합비율을 규명하였다. 수출용 접목선인장인 비모란 선인장(대목: 9 cm 접수: $1.5{\times}1.3cm$ 접목묘) '이홍' 품종을 2013년 6월부터 12월까지 서울시 서초구 내곡동 서울특별시 농업기술센터 플라스틱하우스 내에서 수행하였다. 농가에서 재배하고 있는 모래와 비료를 50:50으로 혼합한 것을 대조구로 하고, 모래와 음식물쓰레기를 먹이로 하여 생산한 지렁이분변토의 혼합비율을 80:20, 60:40, 40:60, 20:80, 0:100으로 한 5조합의 pH는 7.1-7.4로 거의 비슷하게 조사되었는데 비모란선인장 재배의 적정 pH가 6.5-7.5로 적합한 범위였다. 유기물함량은 지렁이분변토 혼합비율이 높아짐에 따라 증가하였지만 관행처리구 55 mg/kg보다는 32-43 mg/kg으로 낮게 조사되었다. 치환성양이온함량은 혼합비율이 증가함에 따라 높아졌지만 관행처리구보다 $K^+$, $Na^+$, $Mg^{2+}$ 양이 적었으나 $Ca^{2+}$의 함량은 관행처리구는 $9.1cmol^+/kg$이나 지렁이분변토 혼합시 $11.5-33.7cmol^+/kg$으로 높게 조사되었다. 지렁이분변토 혼합비율에 따른 비모란선인장 이식 3개월 후 구경을 조사한 결과 대조구 31.39 mm 보다 지렁이분변토 혼합처리구가 32.46-37.59 mm로 유의성 있는 차이를 보였다. 이식 5개월 후 비모란선인장 생육특성을 조사한 결과 구경은 32.63 mm 보다 지렁이분변토처리구가 32.49-37.59 mm로 혼합비율이 증가함에 따라 유의성 있게 신장하였다. 구고는 대조구의 경우 2.63 mm이고 지렁이분변토 혼합비율에 따라 2.79-3.16 mm로 유의성 있게 조사되었다. 자구수가 많이 생기는 것은 농가에는 매우 유리한 상황인데 대조구는 2.7개이고 지렁이분변토 혼합비율이 높아짐에 따라 3.2-8.3개로 조사되어 고도로 유의하였다. 특히 지렁이분변토 80%와 100% 처리구에서 6.2개와 8.3개로 조사되어 대조구보다 2.5배 이상 증가하였는데 비모란선인장 재배농가에서 단기간 자구생산에 활용할 수 있을 것으로 사료되었다. 지렁이분변토 40%와 60% 혼합처리의 경우 자구수가 4.5와 4.8개로 대조구보다 많이 조사되었으며, 토양배수에도 문제가 없었고 이끼가 발생하는 현상도 없었다. 비모란선인장 생육특성을 조사해본 결과 지렁이분변토 40% 및 60% 혼합비율이 생육에 효율적이라고 판단되었다.