This study shows how the growth of the top part of plants cultivated using the single-row strawberry method, with 12 cm plant spacing, as well as that of plants cultivated through conventional planting, is characterized by the presence of many leaves in the first flower cluster harvest. The leaf area and crown diameter were the largest in the 12 cm spacing method. The hight top fresh weight (59.2 g) was detected wen the 12 cm spacing method was used followed by conventional planting and, 9 cm and 6 cm spacing method. The K and Ca contents in the first flower cluster were the highest when the 12 cm spacing method (2.0% and 2.1%, respectively) and conventional planting, (0.42% and 0.86%, respectively) were used, and these values were significantly higher than the K and Ca contents obtained using the other two methods. The N, P, Mg, Fe, and B contents show no significant differences across the planting methods. The sugar content of the first flower cluster fruits was the highest when the 12 cm spacing method was used, while the sugar content of the fourth flower cluster fruits was highest after conventional planting. Firmness was the highest in the first, third, and fourth flower clusters after conventional planting, while no significant differences were observed for the 6 cm, 9 cm, and 12 cm spacing methods. A yield of 25 g or above during November to December was observed to be the highest when the 12 cm spacing method was used, while a yield of 10-16 g was the highest when both the 9 cm and 12 cm spacing methods werw used. The yield of products in January-April was the highest when the 12 cm spacing and conventional planting methods were used, and total product yield was also the highest for these methods. A significant portion of non-marketable products (39 g) was obtained when the conventional planting method was used.

The object of this study was to evaluate the effects of climatic elements on potato yield and create a model for estimating the potato yield. We used 35 yield data of Sumi variety produced in mulching cultivation from 17 regions over 11 years. According to the results, some climatic elements showed significant level of correlation coefficient with marketable yield of potato. Totally 22 items of climatic elements appeared to be significant. Especially precipitation for 20 days after planting (Prec_1 & 2), relative humidity during 11~20 days after planting (RH_2), precipitation for 20 days before harvest (Prec_9 & 10), sunshine hours during 50~41 days before harvest (SH_6) and 20 days before harvest (SH_9 & 10), and days of rain during 10 days before harvest (DR_10) were highly significant in quadratic regression analysis. 22 items of predicted yield (Yi=aXi 2 +bXi+c) were induced from the 22 items of climatic elements (step 1). The correlations between the predicted yields and marketable yield were stepwised using SPSS, statistical program, and we selected a model (step 2), in which 4 items of independent variables (Yi) were used. Subsequently the Yi were replaced with the equation in step 1, aXi 2 +bXi+c. Finally we derived the model to predict the marketable yield of potato as below. Y = -336×DR_10 2 + 854×DR_10 – 0.422×Prec_9 2 + 43.3×Prec_9 – 0.0414×RH_2 2 + 46.2×RH_2 – 0.0102×Prec_2 2 – 7.00×Prec_2 – 10039