The growth and productivity of ribes nigrum under various levels of shade and the implications for multifunctional woody polycultures

Black currant;Ribes nigrum;Shade tolerance;Multifunctional woody polyculture;Understory;Understory crops

Wolske, Eric ; Lovell, Sarah Taylor, ; ,Kling, Gary ; Branham ; Bruce

关键词: Black currant;    Ribes nigrum;    Shade tolerance;    Multifunctional woody polyculture;    Understory;    Understory crops;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/99307/WOLSKE-THESIS-2017.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Black currants (Ribes nigrum) are an important horticultural crop across Europe and parts of Asia. In the United States, however, they have been relegated to a niche market, with little practical use to date. Much of this is due to the illegality of production throughout much of the 20th century, as it was an alternate host to the white pine blister rust (Cronartium ribicola J.C Fisch In Rabh.), which caused extensive damage to the white pine (Pinus strobus) lumber industry. Upon legalization in the latter half of the 20th century, black currants have been making a slow comeback. The major interest in black currants stems from the unique taste and the perceived health benefits. Black currant berries contain a vast array of mineral nutrients that are much higher than many of the major fruits and berries currently in production, with a vitamin C content over three times as high as that found in oranges on a per weight basis. Additionally, they contain high levels of antioxidants due to a large content of phenolic compounds, particularly flavonols and anthocyanins. The stability in frozen storage, as well as the ease of production and machine harvest, mean black currants have a significant potential to provide a new crop to farmers in the Midwest United States. With newly proposed systems for agricultural production focusing on polycultures of perennial crops, a major gap in research is found in the understory layers of these systems. The understory is a unique habitat with intense plant competition for nutrients and water, and most importantly, light. While much is known about plant response mechanisms in these environments, little is known about how crops may perform in these environments. Black currants have been proposed as potential understory crops, but little research has been performed to determine actual agronomic productivity in these environments. An experiment was conducted in Urbana, IL to determine black currant viability in understory environments by exposing black currants to a range of artificial shading. The results of the study indicate black currants can maintain good yields in light to medium levels of shade, with no yield difference found between full sun and up to 65% shading. Additionally, the berries maintained good quality up to the 65% shade level, with sugar levels, acidity, and overall size similar to the control plants. The leaf morphology and height changes under shading were congruent to previous research on plant plasticity responses to shade stress in plants. The major issues found in the study was an increase in plant injury as shading increased, pointing to a need for plant breeding for increased resilience to understory environments to further push for productive plant species in perennial polyculture systems.