Soil and Leaf Chemical Properties and Fruit Quality in Kiwifruit Orchard

Abstract

BACKGROUND: Kiwifruit is a fruit tree with relatively small cultivation area in Korea and researches on its soil and physiology are very limited compared to those on cultivar development. Therefore, there are limited information for farmers to cope with the reduction in productivity due to various physiological disorders and premature aging. This study was conducted to investigate the soil and leaf chemical properties, and fruit characteristics, which will be used as basic data for stable kiwifruit orchard soil management. METHODS AND RESULTS: The soil and leaf chemical properties, and fruit characteristics were investigated for two years in 16 kiwifruit orchards growing 'Hayward' (Actinidia deliciosa) in Jeollanam-do and Gyeongsangnamdo. Soil and leaf samples were collected in July and fruit quality was investigated by harvesting fruits about 170 days after full bloom. The average soil chemical properties of kiwi orchards were generally higher than the recommended level, except for pH, and especially, the exchangeable potassium reached about 300% of the recommended level. The proportions of orchards that exceeded the recommended level of soil chemical properties were 63, 31, 100, 69, 94, 88 and 69% for pH, EC, organic content, available phosphate, and exchangeable potassium, calcium and magnesium, respectively. Thirty-three percent of orchards had more than 100 mg/kg of nitrate nitrogen in soil. Available phosphate in soil showed a significantly positive correlation with leaf nitrogen, phosphoric acid and calcium content, but showed a significantly negative correlation with leaf potassium content. The magnesium content in the leaves was significantly correlated with soil pH. The highest fruit weight was observed in about 25 g/kg of leaf nitrogen content which could be attained when plants were grown on the soil containing about 100 mg/kg of nitrate nitrogen content. The average soluble solids content among 16 orchards was 9.58 °Brix at harvest and 13.9 °Brix after ripening, which increased about 45%, and the average fruit weight was about 110 g. CONCLUSION(S): For fruit quality, fruit soluble solids (sugar compounds) content was significantly correlated with leaf potassium content, fruit hardiness with leaf total nitrate, calcium and magnesium, and fruit titratable acidity with leaf magnesium; however, leaf calcium and magnesium negatively affect the soluble solids contents in fruits.

Contribution of soil and crop parameters on sudangrass productivity based on farm survey

“…따라서 양분 손실을 최소화하면서 작물의 수량과 품질을 향상시키기 위해서는 수단그라스 재배지의 토 양 및 식물 영양 특성을 파악하고 두 특성 간에 미치는 영향에 대한 분석을 통해 생산성을 평가하고 적정 비료량을 설 정하는 것이 중요하다. 복숭아, 인삼, 딸기, 키위, 구지뽕나무 등의 작물은 토양화학성과 식물체 잎의 양분함량과의 관 계를 바탕으로 적정 비료 기준을 제시한 바 있다 (Seo et al, 2002;Jin et al, 2009;Choi et al, 2010;Kim et al, 2022;Song et al, 2022). 따라서, 본 연구에서는 수단그라스 재배농가의 수량에 따른 질소비료사용량, 토양화학성, 식물체 질소함량, 질소이용효율 등을 분석하여, 생산성에 대한 환경 또는 재배요인의 영향을 평가하고자 수행하였다.…”